android_kernel_xiaomi_sm8350/arch/x86/kernel/apic_32.c

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/*
* Local APIC handling, local APIC timers
*
* (c) 1999, 2000 Ingo Molnar <mingo@redhat.com>
*
* Fixes
* Maciej W. Rozycki : Bits for genuine 82489DX APICs;
* thanks to Eric Gilmore
* and Rolf G. Tews
* for testing these extensively.
* Maciej W. Rozycki : Various updates and fixes.
* Mikael Pettersson : Power Management for UP-APIC.
* Pavel Machek and
* Mikael Pettersson : PM converted to driver model.
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/bootmem.h>
#include <linux/interrupt.h>
#include <linux/mc146818rtc.h>
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
[PATCH] i386 CPU hotplug (The i386 CPU hotplug patch provides infrastructure for some work which Pavel is doing as well as for ACPI S3 (suspend-to-RAM) work which Li Shaohua <shaohua.li@intel.com> is doing) The following provides i386 architecture support for safely unregistering and registering processors during runtime, updated for the current -mm tree. In order to avoid dumping cpu hotplug code into kernel/irq/* i dropped the cpu_online check in do_IRQ() by modifying fixup_irqs(). The difference being that on cpu offline, fixup_irqs() is called before we clear the cpu from cpu_online_map and a long delay in order to ensure that we never have any queued external interrupts on the APICs. There are additional changes to s390 and ppc64 to account for this change. 1) Add CONFIG_HOTPLUG_CPU 2) disable local APIC timer on dead cpus. 3) Disable preempt around irq balancing to prevent CPUs going down. 4) Print irq stats for all possible cpus. 5) Debugging check for interrupts on offline cpus. 6) Hacky fixup_irqs() to redirect irqs when cpus go off/online. 7) play_dead() for offline cpus to spin inside. 8) Handle offline cpus set in flush_tlb_others(). 9) Grab lock earlier in smp_call_function() to prevent CPUs going down. 10) Implement __cpu_disable() and __cpu_die(). 11) Enable local interrupts in cpu_enable() after fixup_irqs() 12) Don't fiddle with NMI on dead cpu, but leave intact on other cpus. 13) Program IRQ affinity whilst cpu is still in cpu_online_map on offline. Signed-off-by: Zwane Mwaikambo <zwane@linuxpower.ca> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 17:54:50 -04:00
#include <linux/cpu.h>
#include <linux/clockchips.h>
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
#include <linux/acpi_pmtmr.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <asm/atomic.h>
#include <asm/smp.h>
#include <asm/mtrr.h>
#include <asm/mpspec.h>
#include <asm/desc.h>
#include <asm/arch_hooks.h>
#include <asm/hpet.h>
#include <asm/i8253.h>
#include <asm/nmi.h>
#include <mach_apic.h>
#include <mach_apicdef.h>
#include <mach_ipi.h>
/*
* Sanity check
*/
#if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
# error SPURIOUS_APIC_VECTOR definition error
#endif
/*
* Knob to control our willingness to enable the local APIC.
*
* -1=force-disable, +1=force-enable
*/
static int enable_local_apic __initdata;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Local APIC timer verification ok */
static int local_apic_timer_verify_ok;
/* Disable local APIC timer from the kernel commandline or via dmi quirk
or using CPU MSR check */
int local_apic_timer_disabled;
/* Local APIC timer works in C2 */
int local_apic_timer_c2_ok;
EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
/*
* Debug level, exported for io_apic.c
*/
int apic_verbosity;
static unsigned int calibration_result;
static int lapic_next_event(unsigned long delta,
struct clock_event_device *evt);
static void lapic_timer_setup(enum clock_event_mode mode,
struct clock_event_device *evt);
static void lapic_timer_broadcast(cpumask_t mask);
static void apic_pm_activate(void);
/*
* The local apic timer can be used for any function which is CPU local.
*/
static struct clock_event_device lapic_clockevent = {
.name = "lapic",
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
.shift = 32,
.set_mode = lapic_timer_setup,
.set_next_event = lapic_next_event,
.broadcast = lapic_timer_broadcast,
.rating = 100,
.irq = -1,
};
static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
/* Local APIC was disabled by the BIOS and enabled by the kernel */
static int enabled_via_apicbase;
static unsigned long apic_phys;
/*
* Get the LAPIC version
*/
static inline int lapic_get_version(void)
{
return GET_APIC_VERSION(apic_read(APIC_LVR));
}
/*
* Check, if the APIC is integrated or a separate chip
*/
static inline int lapic_is_integrated(void)
{
return APIC_INTEGRATED(lapic_get_version());
}
/*
* Check, whether this is a modern or a first generation APIC
*/
static int modern_apic(void)
{
/* AMD systems use old APIC versions, so check the CPU */
if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
boot_cpu_data.x86 >= 0xf)
return 1;
return lapic_get_version() >= 0x14;
}
[PATCH] i386: safe_apic_wait_icr_idle - i386 apic_wait_icr_idle looks like this: static __inline__ void apic_wait_icr_idle(void) { while (apic_read(APIC_ICR) & APIC_ICR_BUSY) cpu_relax(); } The busy loop in this function would not be problematic if the corresponding status bit in the ICR were always updated, but that does not seem to be the case under certain crash scenarios. Kdump uses an IPI to stop the other CPUs in the event of a crash, but when any of the other CPUs are locked-up inside the NMI handler the CPU that sends the IPI will end up looping forever in the ICR check, effectively hard-locking the whole system. Quoting from Intel's "MultiProcessor Specification" (Version 1.4), B-3: "A local APIC unit indicates successful dispatch of an IPI by resetting the Delivery Status bit in the Interrupt Command Register (ICR). The operating system polls the delivery status bit after sending an INIT or STARTUP IPI until the command has been dispatched. A period of 20 microseconds should be sufficient for IPI dispatch to complete under normal operating conditions. If the IPI is not successfully dispatched, the operating system can abort the command. Alternatively, the operating system can retry the IPI by writing the lower 32-bit double word of the ICR. This “time-out” mechanism can be implemented through an external interrupt, if interrupts are enabled on the processor, or through execution of an instruction or time-stamp counter spin loop." Intel's documentation suggests the implementation of a time-out mechanism, which, by the way, is already being open-coded in some parts of the kernel that tinker with ICR. Create a apic_wait_icr_idle replacement that implements the time-out mechanism and that can be used to solve the aforementioned problem. AK: moved both functions out of line AK: added improved loop from Keith Owens Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 13:27:17 -04:00
void apic_wait_icr_idle(void)
{
while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
cpu_relax();
}
u32 safe_apic_wait_icr_idle(void)
[PATCH] i386: safe_apic_wait_icr_idle - i386 apic_wait_icr_idle looks like this: static __inline__ void apic_wait_icr_idle(void) { while (apic_read(APIC_ICR) & APIC_ICR_BUSY) cpu_relax(); } The busy loop in this function would not be problematic if the corresponding status bit in the ICR were always updated, but that does not seem to be the case under certain crash scenarios. Kdump uses an IPI to stop the other CPUs in the event of a crash, but when any of the other CPUs are locked-up inside the NMI handler the CPU that sends the IPI will end up looping forever in the ICR check, effectively hard-locking the whole system. Quoting from Intel's "MultiProcessor Specification" (Version 1.4), B-3: "A local APIC unit indicates successful dispatch of an IPI by resetting the Delivery Status bit in the Interrupt Command Register (ICR). The operating system polls the delivery status bit after sending an INIT or STARTUP IPI until the command has been dispatched. A period of 20 microseconds should be sufficient for IPI dispatch to complete under normal operating conditions. If the IPI is not successfully dispatched, the operating system can abort the command. Alternatively, the operating system can retry the IPI by writing the lower 32-bit double word of the ICR. This “time-out” mechanism can be implemented through an external interrupt, if interrupts are enabled on the processor, or through execution of an instruction or time-stamp counter spin loop." Intel's documentation suggests the implementation of a time-out mechanism, which, by the way, is already being open-coded in some parts of the kernel that tinker with ICR. Create a apic_wait_icr_idle replacement that implements the time-out mechanism and that can be used to solve the aforementioned problem. AK: moved both functions out of line AK: added improved loop from Keith Owens Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 13:27:17 -04:00
{
u32 send_status;
[PATCH] i386: safe_apic_wait_icr_idle - i386 apic_wait_icr_idle looks like this: static __inline__ void apic_wait_icr_idle(void) { while (apic_read(APIC_ICR) & APIC_ICR_BUSY) cpu_relax(); } The busy loop in this function would not be problematic if the corresponding status bit in the ICR were always updated, but that does not seem to be the case under certain crash scenarios. Kdump uses an IPI to stop the other CPUs in the event of a crash, but when any of the other CPUs are locked-up inside the NMI handler the CPU that sends the IPI will end up looping forever in the ICR check, effectively hard-locking the whole system. Quoting from Intel's "MultiProcessor Specification" (Version 1.4), B-3: "A local APIC unit indicates successful dispatch of an IPI by resetting the Delivery Status bit in the Interrupt Command Register (ICR). The operating system polls the delivery status bit after sending an INIT or STARTUP IPI until the command has been dispatched. A period of 20 microseconds should be sufficient for IPI dispatch to complete under normal operating conditions. If the IPI is not successfully dispatched, the operating system can abort the command. Alternatively, the operating system can retry the IPI by writing the lower 32-bit double word of the ICR. This “time-out” mechanism can be implemented through an external interrupt, if interrupts are enabled on the processor, or through execution of an instruction or time-stamp counter spin loop." Intel's documentation suggests the implementation of a time-out mechanism, which, by the way, is already being open-coded in some parts of the kernel that tinker with ICR. Create a apic_wait_icr_idle replacement that implements the time-out mechanism and that can be used to solve the aforementioned problem. AK: moved both functions out of line AK: added improved loop from Keith Owens Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 13:27:17 -04:00
int timeout;
timeout = 0;
do {
send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
if (!send_status)
break;
udelay(100);
} while (timeout++ < 1000);
return send_status;
}
/**
* enable_NMI_through_LVT0 - enable NMI through local vector table 0
*/
void __cpuinit enable_NMI_through_LVT0(void)
{
unsigned int v = APIC_DM_NMI;
/* Level triggered for 82489DX */
if (!lapic_is_integrated())
v |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT0, v);
}
/**
* get_physical_broadcast - Get number of physical broadcast IDs
*/
int get_physical_broadcast(void)
{
return modern_apic() ? 0xff : 0xf;
}
/**
* lapic_get_maxlvt - get the maximum number of local vector table entries
*/
int lapic_get_maxlvt(void)
{
unsigned int v = apic_read(APIC_LVR);
/* 82489DXs do not report # of LVT entries. */
return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
}
/*
* Local APIC timer
*/
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Clock divisor is set to 16 */
#define APIC_DIVISOR 16
/*
* This function sets up the local APIC timer, with a timeout of
* 'clocks' APIC bus clock. During calibration we actually call
* this function twice on the boot CPU, once with a bogus timeout
* value, second time for real. The other (noncalibrating) CPUs
* call this function only once, with the real, calibrated value.
*
* We do reads before writes even if unnecessary, to get around the
* P5 APIC double write bug.
*/
static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
{
unsigned int lvtt_value, tmp_value;
lvtt_value = LOCAL_TIMER_VECTOR;
if (!oneshot)
lvtt_value |= APIC_LVT_TIMER_PERIODIC;
if (!lapic_is_integrated())
lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
if (!irqen)
lvtt_value |= APIC_LVT_MASKED;
apic_write_around(APIC_LVTT, lvtt_value);
/*
* Divide PICLK by 16
*/
tmp_value = apic_read(APIC_TDCR);
apic_write_around(APIC_TDCR, (tmp_value
& ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
| APIC_TDR_DIV_16);
if (!oneshot)
apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
}
/*
* Program the next event, relative to now
*/
static int lapic_next_event(unsigned long delta,
struct clock_event_device *evt)
{
apic_write_around(APIC_TMICT, delta);
return 0;
}
/*
* Setup the lapic timer in periodic or oneshot mode
*/
static void lapic_timer_setup(enum clock_event_mode mode,
struct clock_event_device *evt)
{
unsigned long flags;
unsigned int v;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Lapic used for broadcast ? */
if (!local_apic_timer_verify_ok)
return;
local_irq_save(flags);
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
case CLOCK_EVT_MODE_ONESHOT:
__setup_APIC_LVTT(calibration_result,
mode != CLOCK_EVT_MODE_PERIODIC, 1);
break;
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
v = apic_read(APIC_LVTT);
v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
apic_write_around(APIC_LVTT, v);
break;
case CLOCK_EVT_MODE_RESUME:
/* Nothing to do here */
break;
}
local_irq_restore(flags);
}
/*
* Local APIC timer broadcast function
*/
static void lapic_timer_broadcast(cpumask_t mask)
{
#ifdef CONFIG_SMP
send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
#endif
}
/*
* Setup the local APIC timer for this CPU. Copy the initilized values
* of the boot CPU and register the clock event in the framework.
*/
static void __devinit setup_APIC_timer(void)
{
struct clock_event_device *levt = &__get_cpu_var(lapic_events);
memcpy(levt, &lapic_clockevent, sizeof(*levt));
levt->cpumask = cpumask_of_cpu(smp_processor_id());
clockevents_register_device(levt);
}
/*
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
* In this functions we calibrate APIC bus clocks to the external timer.
*
* We want to do the calibration only once since we want to have local timer
* irqs syncron. CPUs connected by the same APIC bus have the very same bus
* frequency.
*
* This was previously done by reading the PIT/HPET and waiting for a wrap
* around to find out, that a tick has elapsed. I have a box, where the PIT
* readout is broken, so it never gets out of the wait loop again. This was
* also reported by others.
*
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
* Monitoring the jiffies value is inaccurate and the clockevents
* infrastructure allows us to do a simple substitution of the interrupt
* handler.
*
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
* The calibration routine also uses the pm_timer when possible, as the PIT
* happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
* back to normal later in the boot process).
*/
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
#define LAPIC_CAL_LOOPS (HZ/10)
static __initdata int lapic_cal_loops = -1;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
static __initdata long lapic_cal_t1, lapic_cal_t2;
static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/*
* Temporary interrupt handler.
*/
static void __init lapic_cal_handler(struct clock_event_device *dev)
{
unsigned long long tsc = 0;
long tapic = apic_read(APIC_TMCCT);
unsigned long pm = acpi_pm_read_early();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
if (cpu_has_tsc)
rdtscll(tsc);
switch (lapic_cal_loops++) {
case 0:
lapic_cal_t1 = tapic;
lapic_cal_tsc1 = tsc;
lapic_cal_pm1 = pm;
lapic_cal_j1 = jiffies;
break;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
case LAPIC_CAL_LOOPS:
lapic_cal_t2 = tapic;
lapic_cal_tsc2 = tsc;
if (pm < lapic_cal_pm1)
pm += ACPI_PM_OVRRUN;
lapic_cal_pm2 = pm;
lapic_cal_j2 = jiffies;
break;
}
}
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/*
* Setup the boot APIC
*
* Calibrate and verify the result.
*/
void __init setup_boot_APIC_clock(void)
{
struct clock_event_device *levt = &__get_cpu_var(lapic_events);
const long pm_100ms = PMTMR_TICKS_PER_SEC/10;
const long pm_thresh = pm_100ms/100;
void (*real_handler)(struct clock_event_device *dev);
unsigned long deltaj;
long delta, deltapm;
int pm_referenced = 0;
/*
* The local apic timer can be disabled via the kernel
* commandline or from the CPU detection code. Register the lapic
* timer as a dummy clock event source on SMP systems, so the
* broadcast mechanism is used. On UP systems simply ignore it.
*/
if (local_apic_timer_disabled) {
/* No broadcast on UP ! */
if (num_possible_cpus() > 1) {
lapic_clockevent.mult = 1;
setup_APIC_timer();
}
return;
}
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
"calibrating APIC timer ...\n");
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
local_irq_disable();
/* Replace the global interrupt handler */
real_handler = global_clock_event->event_handler;
global_clock_event->event_handler = lapic_cal_handler;
/*
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
* Setup the APIC counter to 1e9. There is no way the lapic
* can underflow in the 100ms detection time frame
*/
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
__setup_APIC_LVTT(1000000000, 0, 0);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Let the interrupts run */
local_irq_enable();
while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
cpu_relax();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
local_irq_disable();
/* Restore the real event handler */
global_clock_event->event_handler = real_handler;
/* Build delta t1-t2 as apic timer counts down */
delta = lapic_cal_t1 - lapic_cal_t2;
apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
/* Check, if the PM timer is available */
deltapm = lapic_cal_pm2 - lapic_cal_pm1;
apic_printk(APIC_VERBOSE, "... PM timer delta = %ld\n", deltapm);
if (deltapm) {
unsigned long mult;
u64 res;
mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
if (deltapm > (pm_100ms - pm_thresh) &&
deltapm < (pm_100ms + pm_thresh)) {
apic_printk(APIC_VERBOSE, "... PM timer result ok\n");
} else {
res = (((u64) deltapm) * mult) >> 22;
do_div(res, 1000000);
printk(KERN_WARNING "APIC calibration not consistent "
"with PM Timer: %ldms instead of 100ms\n",
(long)res);
/* Correct the lapic counter value */
res = (((u64) delta) * pm_100ms);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
do_div(res, deltapm);
printk(KERN_INFO "APIC delta adjusted to PM-Timer: "
"%lu (%ld)\n", (unsigned long) res, delta);
delta = (long) res;
}
pm_referenced = 1;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
}
/* Calculate the scaled math multiplication factor */
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS, 32);
lapic_clockevent.max_delta_ns =
clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
lapic_clockevent.min_delta_ns =
clockevent_delta2ns(0xF, &lapic_clockevent);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
calibration_result);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
if (cpu_has_tsc) {
delta = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
"%ld.%04ld MHz.\n",
(delta / LAPIC_CAL_LOOPS) / (1000000 / HZ),
(delta / LAPIC_CAL_LOOPS) % (1000000 / HZ));
}
apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
"%u.%04u MHz.\n",
calibration_result / (1000000 / HZ),
calibration_result % (1000000 / HZ));
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
local_apic_timer_verify_ok = 1;
/*
* Do a sanity check on the APIC calibration result
*/
if (calibration_result < (1000000 / HZ)) {
local_irq_enable();
printk(KERN_WARNING
"APIC frequency too slow, disabling apic timer\n");
/* No broadcast on UP ! */
if (num_possible_cpus() > 1)
setup_APIC_timer();
return;
}
/* We trust the pm timer based calibration */
if (!pm_referenced) {
apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/*
* Setup the apic timer manually
*/
levt->event_handler = lapic_cal_handler;
lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
lapic_cal_loops = -1;
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Let the interrupts run */
local_irq_enable();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
cpu_relax();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
local_irq_disable();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Stop the lapic timer */
lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
local_irq_enable();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Jiffies delta */
deltaj = lapic_cal_j2 - lapic_cal_j1;
apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Check, if the jiffies result is consistent */
if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
else
local_apic_timer_verify_ok = 0;
} else
local_irq_enable();
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
if (!local_apic_timer_verify_ok) {
printk(KERN_WARNING
"APIC timer disabled due to verification failure.\n");
/* No broadcast on UP ! */
if (num_possible_cpus() == 1)
return;
} else {
/*
* If nmi_watchdog is set to IO_APIC, we need the
* PIT/HPET going. Otherwise register lapic as a dummy
* device.
*/
if (nmi_watchdog != NMI_IO_APIC)
lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
else
printk(KERN_WARNING "APIC timer registered as dummy,"
" due to nmi_watchdog=1!\n");
}
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
/* Setup the lapic or request the broadcast */
setup_APIC_timer();
}
void __devinit setup_secondary_APIC_clock(void)
{
setup_APIC_timer();
}
/*
* The guts of the apic timer interrupt
*/
static void local_apic_timer_interrupt(void)
{
int cpu = smp_processor_id();
struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
/*
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
* Normally we should not be here till LAPIC has been initialized but
* in some cases like kdump, its possible that there is a pending LAPIC
* timer interrupt from previous kernel's context and is delivered in
* new kernel the moment interrupts are enabled.
*
[PATCH] i386 rework local apic timer calibration The local apic timer calibration has two problem cases: 1. The calibration is based on readout of the PIT/HPET timer to detect the wrap of the periodic tick. It happens that a box gets stuck in the calibration loop due to a PIT with a broken readout function. 2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results in a wrong lapic calibration. The PIT goes back to normal operation once the lapic timer is switched to periodic mode. Both are existing and unfixed problems in the current upstream kernel and prevent certain laptops and other systems from booting Linux. Rework the code to address both problems: - Make the calibration interrupt driven. This removes the wait_timer_tick magic hackery from lapic.c and time_hpet.c. The clockevents framework allows easy substitution of the global tick event handler for the calibration. This is more accurate than monitoring jiffies. At this point of the boot process, nothing disturbes the interrupt delivery, so the results are very accurate. - Verify the calibration against the PM timer, when available by using the early access function. When the measured calibration period is outside of an one percent window, then the lapic timer calibration is adjusted to the pm timer result. - Verify the calibration by running the lapic timer with the calibration handler. Disable lapic timer in case of deviation. This also removes the "synchronization" of the local apic timer to the global tick. This synchronization never worked, as there is no way to synchronize PIT(HPET) and local APIC timer. The synchronization by waiting for the tick just alignes the local APIC timer for the first events, but later the events drift away due to the different clocks. Removing the "sync" is just randomizing the asynchronous behaviour at setup time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Zachary Amsden <zach@vmware.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 04:28:06 -05:00
* Interrupts are enabled early and LAPIC is setup much later, hence
* its possible that when we get here evt->event_handler is NULL.
* Check for event_handler being NULL and discard the interrupt as
* spurious.
*/
if (!evt->event_handler) {
printk(KERN_WARNING
"Spurious LAPIC timer interrupt on cpu %d\n", cpu);
/* Switch it off */
lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
return;
}
/*
* the NMI deadlock-detector uses this.
*/
per_cpu(irq_stat, cpu).apic_timer_irqs++;
evt->event_handler(evt);
}
/*
* Local APIC timer interrupt. This is the most natural way for doing
* local interrupts, but local timer interrupts can be emulated by
* broadcast interrupts too. [in case the hw doesn't support APIC timers]
*
* [ if a single-CPU system runs an SMP kernel then we call the local
* interrupt as well. Thus we cannot inline the local irq ... ]
*/
void smp_apic_timer_interrupt(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
/*
* NOTE! We'd better ACK the irq immediately,
* because timer handling can be slow.
*/
ack_APIC_irq();
[PATCH] i386 kdump timer vector lockup fix Porting the patch I posted for x86_64 to i386. http://marc.theaimsgroup.com/?l=linux-kernel&m=114178139610707&w=2 o While using kdump, after a system crash when second kernel boots, timer vector gets (0x31) locked and CPU does not see timer interrupts travelling from IOAPIC to APIC. Currently it does not lead to boot failure in second kernel as timer interrupts continues to come as ExtInt through LAPIC directly, but fixing it is good in case some boards do not support the other mode. o After a system crash, it is not safe to service interrupts any more, hence interrupts are disabled. This leads to pending interrupts at LAPIC. LAPIC sends these interrupts to the CPU during early boot of second kernel. Other pending interrupts are discarded saying unexpected trap but timer interrupt is serviced and CPU does not issue an LAPIC EOI because it think this interrupt came from i8259 and sends ack to 8259. This leads to vector 0x31 locking as LAPIC does not clear respective ISR and keeps on waiting for EOI. o This patch issues extra EOI for the pending interrupts who have ISR set. o Though today only timer seems to be the special case because in early boot it thinks interrupts are coming from i8259 and uses mask_and_ack_8259A() as ack handler and does not issue LAPIC EOI. But probably doing it in generic manner for all vectors makes sense. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 05:30:05 -05:00
/*
* update_process_times() expects us to have done irq_enter().
* Besides, if we don't timer interrupts ignore the global
* interrupt lock, which is the WrongThing (tm) to do.
[PATCH] i386 kdump timer vector lockup fix Porting the patch I posted for x86_64 to i386. http://marc.theaimsgroup.com/?l=linux-kernel&m=114178139610707&w=2 o While using kdump, after a system crash when second kernel boots, timer vector gets (0x31) locked and CPU does not see timer interrupts travelling from IOAPIC to APIC. Currently it does not lead to boot failure in second kernel as timer interrupts continues to come as ExtInt through LAPIC directly, but fixing it is good in case some boards do not support the other mode. o After a system crash, it is not safe to service interrupts any more, hence interrupts are disabled. This leads to pending interrupts at LAPIC. LAPIC sends these interrupts to the CPU during early boot of second kernel. Other pending interrupts are discarded saying unexpected trap but timer interrupt is serviced and CPU does not issue an LAPIC EOI because it think this interrupt came from i8259 and sends ack to 8259. This leads to vector 0x31 locking as LAPIC does not clear respective ISR and keeps on waiting for EOI. o This patch issues extra EOI for the pending interrupts who have ISR set. o Though today only timer seems to be the special case because in early boot it thinks interrupts are coming from i8259 and uses mask_and_ack_8259A() as ack handler and does not issue LAPIC EOI. But probably doing it in generic manner for all vectors makes sense. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 05:30:05 -05:00
*/
irq_enter();
local_apic_timer_interrupt();
irq_exit();
[PATCH] i386 kdump timer vector lockup fix Porting the patch I posted for x86_64 to i386. http://marc.theaimsgroup.com/?l=linux-kernel&m=114178139610707&w=2 o While using kdump, after a system crash when second kernel boots, timer vector gets (0x31) locked and CPU does not see timer interrupts travelling from IOAPIC to APIC. Currently it does not lead to boot failure in second kernel as timer interrupts continues to come as ExtInt through LAPIC directly, but fixing it is good in case some boards do not support the other mode. o After a system crash, it is not safe to service interrupts any more, hence interrupts are disabled. This leads to pending interrupts at LAPIC. LAPIC sends these interrupts to the CPU during early boot of second kernel. Other pending interrupts are discarded saying unexpected trap but timer interrupt is serviced and CPU does not issue an LAPIC EOI because it think this interrupt came from i8259 and sends ack to 8259. This leads to vector 0x31 locking as LAPIC does not clear respective ISR and keeps on waiting for EOI. o This patch issues extra EOI for the pending interrupts who have ISR set. o Though today only timer seems to be the special case because in early boot it thinks interrupts are coming from i8259 and uses mask_and_ack_8259A() as ack handler and does not issue LAPIC EOI. But probably doing it in generic manner for all vectors makes sense. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 05:30:05 -05:00
set_irq_regs(old_regs);
}
int setup_profiling_timer(unsigned int multiplier)
{
return -EINVAL;
}
/*
* Local APIC start and shutdown
*/
/**
* clear_local_APIC - shutdown the local APIC
*
* This is called, when a CPU is disabled and before rebooting, so the state of
* the local APIC has no dangling leftovers. Also used to cleanout any BIOS
* leftovers during boot.
*/
void clear_local_APIC(void)
{
int maxlvt;
u32 v;
/* APIC hasn't been mapped yet */
if (!apic_phys)
return;
maxlvt = lapic_get_maxlvt();
/*
* Masking an LVT entry can trigger a local APIC error
* if the vector is zero. Mask LVTERR first to prevent this.
*/
if (maxlvt >= 3) {
v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
}
/*
* Careful: we have to set masks only first to deassert
* any level-triggered sources.
*/
v = apic_read(APIC_LVTT);
apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
v = apic_read(APIC_LVT0);
apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
v = apic_read(APIC_LVT1);
apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
if (maxlvt >= 4) {
v = apic_read(APIC_LVTPC);
apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
}
/* lets not touch this if we didn't frob it */
#ifdef CONFIG_X86_MCE_P4THERMAL
if (maxlvt >= 5) {
v = apic_read(APIC_LVTTHMR);
apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
}
#endif
/*
* Clean APIC state for other OSs:
*/
apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
if (maxlvt >= 3)
apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
if (maxlvt >= 4)
apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);
#ifdef CONFIG_X86_MCE_P4THERMAL
if (maxlvt >= 5)
apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
#endif
/* Integrated APIC (!82489DX) ? */
if (lapic_is_integrated()) {
if (maxlvt > 3)
/* Clear ESR due to Pentium errata 3AP and 11AP */
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
}
}
/**
* disable_local_APIC - clear and disable the local APIC
*/
void disable_local_APIC(void)
{
unsigned long value;
clear_local_APIC();
/*
* Disable APIC (implies clearing of registers
* for 82489DX!).
*/
value = apic_read(APIC_SPIV);
value &= ~APIC_SPIV_APIC_ENABLED;
apic_write_around(APIC_SPIV, value);
/*
* When LAPIC was disabled by the BIOS and enabled by the kernel,
* restore the disabled state.
*/
if (enabled_via_apicbase) {
unsigned int l, h;
rdmsr(MSR_IA32_APICBASE, l, h);
l &= ~MSR_IA32_APICBASE_ENABLE;
wrmsr(MSR_IA32_APICBASE, l, h);
}
}
/*
* If Linux enabled the LAPIC against the BIOS default disable it down before
* re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
* not power-off. Additionally clear all LVT entries before disable_local_APIC
* for the case where Linux didn't enable the LAPIC.
*/
void lapic_shutdown(void)
{
unsigned long flags;
if (!cpu_has_apic)
return;
local_irq_save(flags);
clear_local_APIC();
if (enabled_via_apicbase)
disable_local_APIC();
local_irq_restore(flags);
}
/*
* This is to verify that we're looking at a real local APIC.
* Check these against your board if the CPUs aren't getting
* started for no apparent reason.
*/
int __init verify_local_APIC(void)
{
unsigned int reg0, reg1;
/*
* The version register is read-only in a real APIC.
*/
reg0 = apic_read(APIC_LVR);
apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
reg1 = apic_read(APIC_LVR);
apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
/*
* The two version reads above should print the same
* numbers. If the second one is different, then we
* poke at a non-APIC.
*/
if (reg1 != reg0)
return 0;
/*
* Check if the version looks reasonably.
*/
reg1 = GET_APIC_VERSION(reg0);
if (reg1 == 0x00 || reg1 == 0xff)
return 0;
reg1 = lapic_get_maxlvt();
if (reg1 < 0x02 || reg1 == 0xff)
return 0;
/*
* The ID register is read/write in a real APIC.
*/
reg0 = apic_read(APIC_ID);
apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
/*
* The next two are just to see if we have sane values.
* They're only really relevant if we're in Virtual Wire
* compatibility mode, but most boxes are anymore.
*/
reg0 = apic_read(APIC_LVT0);
apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
reg1 = apic_read(APIC_LVT1);
apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
return 1;
}
/**
* sync_Arb_IDs - synchronize APIC bus arbitration IDs
*/
void __init sync_Arb_IDs(void)
{
/*
* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
* needed on AMD.
*/
if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
return;
/*
* Wait for idle.
*/
apic_wait_icr_idle();
apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
| APIC_DM_INIT);
}
/*
* An initial setup of the virtual wire mode.
*/
void __init init_bsp_APIC(void)
{
unsigned long value;
/*
* Don't do the setup now if we have a SMP BIOS as the
* through-I/O-APIC virtual wire mode might be active.
*/
if (smp_found_config || !cpu_has_apic)
return;
/*
* Do not trust the local APIC being empty at bootup.
*/
clear_local_APIC();
/*
* Enable APIC.
*/
value = apic_read(APIC_SPIV);
value &= ~APIC_VECTOR_MASK;
value |= APIC_SPIV_APIC_ENABLED;
/* This bit is reserved on P4/Xeon and should be cleared */
if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
(boot_cpu_data.x86 == 15))
value &= ~APIC_SPIV_FOCUS_DISABLED;
else
value |= APIC_SPIV_FOCUS_DISABLED;
value |= SPURIOUS_APIC_VECTOR;
apic_write_around(APIC_SPIV, value);
/*
* Set up the virtual wire mode.
*/
apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
value = APIC_DM_NMI;
if (!lapic_is_integrated()) /* 82489DX */
value |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT1, value);
}
/**
* setup_local_APIC - setup the local APIC
*/
void __cpuinit setup_local_APIC(void)
{
unsigned long oldvalue, value, maxlvt, integrated;
int i, j;
/* Pound the ESR really hard over the head with a big hammer - mbligh */
if (esr_disable) {
apic_write(APIC_ESR, 0);
apic_write(APIC_ESR, 0);
apic_write(APIC_ESR, 0);
apic_write(APIC_ESR, 0);
}
integrated = lapic_is_integrated();
/*
* Double-check whether this APIC is really registered.
*/
if (!apic_id_registered())
BUG();
/*
* Intel recommends to set DFR, LDR and TPR before enabling
* an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
* document number 292116). So here it goes...
*/
init_apic_ldr();
/*
* Set Task Priority to 'accept all'. We never change this
* later on.
*/
value = apic_read(APIC_TASKPRI);
value &= ~APIC_TPRI_MASK;
apic_write_around(APIC_TASKPRI, value);
/*
* After a crash, we no longer service the interrupts and a pending
* interrupt from previous kernel might still have ISR bit set.
*
* Most probably by now CPU has serviced that pending interrupt and
* it might not have done the ack_APIC_irq() because it thought,
* interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
* does not clear the ISR bit and cpu thinks it has already serivced
* the interrupt. Hence a vector might get locked. It was noticed
* for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
*/
for (i = APIC_ISR_NR - 1; i >= 0; i--) {
value = apic_read(APIC_ISR + i*0x10);
for (j = 31; j >= 0; j--) {
if (value & (1<<j))
ack_APIC_irq();
}
}
/*
* Now that we are all set up, enable the APIC
*/
value = apic_read(APIC_SPIV);
value &= ~APIC_VECTOR_MASK;
/*
* Enable APIC
*/
value |= APIC_SPIV_APIC_ENABLED;
/*
* Some unknown Intel IO/APIC (or APIC) errata is biting us with
* certain networking cards. If high frequency interrupts are
* happening on a particular IOAPIC pin, plus the IOAPIC routing
* entry is masked/unmasked at a high rate as well then sooner or
* later IOAPIC line gets 'stuck', no more interrupts are received
* from the device. If focus CPU is disabled then the hang goes
* away, oh well :-(
*
* [ This bug can be reproduced easily with a level-triggered
* PCI Ne2000 networking cards and PII/PIII processors, dual
* BX chipset. ]
*/
/*
* Actually disabling the focus CPU check just makes the hang less
* frequent as it makes the interrupt distributon model be more
* like LRU than MRU (the short-term load is more even across CPUs).
* See also the comment in end_level_ioapic_irq(). --macro
*/
/* Enable focus processor (bit==0) */
value &= ~APIC_SPIV_FOCUS_DISABLED;
/*
* Set spurious IRQ vector
*/
value |= SPURIOUS_APIC_VECTOR;
apic_write_around(APIC_SPIV, value);
/*
* Set up LVT0, LVT1:
*
* set up through-local-APIC on the BP's LINT0. This is not
* strictly necessary in pure symmetric-IO mode, but sometimes
* we delegate interrupts to the 8259A.
*/
/*
* TODO: set up through-local-APIC from through-I/O-APIC? --macro
*/
value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
if (!smp_processor_id() && (pic_mode || !value)) {
value = APIC_DM_EXTINT;
apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
smp_processor_id());
} else {
value = APIC_DM_EXTINT | APIC_LVT_MASKED;
apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
smp_processor_id());
}
apic_write_around(APIC_LVT0, value);
/*
* only the BP should see the LINT1 NMI signal, obviously.
*/
if (!smp_processor_id())
value = APIC_DM_NMI;
else
value = APIC_DM_NMI | APIC_LVT_MASKED;
if (!integrated) /* 82489DX */
value |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT1, value);
if (integrated && !esr_disable) {
/* !82489DX */
maxlvt = lapic_get_maxlvt();
if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
apic_write(APIC_ESR, 0);
oldvalue = apic_read(APIC_ESR);
/* enables sending errors */
value = ERROR_APIC_VECTOR;
apic_write_around(APIC_LVTERR, value);
/*
* spec says clear errors after enabling vector.
*/
if (maxlvt > 3)
apic_write(APIC_ESR, 0);
value = apic_read(APIC_ESR);
if (value != oldvalue)
apic_printk(APIC_VERBOSE, "ESR value before enabling "
"vector: 0x%08lx after: 0x%08lx\n",
oldvalue, value);
} else {
if (esr_disable)
/*
* Something untraceable is creating bad interrupts on
* secondary quads ... for the moment, just leave the
* ESR disabled - we can't do anything useful with the
* errors anyway - mbligh
*/
printk(KERN_INFO "Leaving ESR disabled.\n");
else
printk(KERN_INFO "No ESR for 82489DX.\n");
}
/* Disable the local apic timer */
value = apic_read(APIC_LVTT);
value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
apic_write_around(APIC_LVTT, value);
setup_apic_nmi_watchdog(NULL);
apic_pm_activate();
}
/*
* Detect and initialize APIC
*/
static int __init detect_init_APIC(void)
{
u32 h, l, features;
/* Disabled by kernel option? */
if (enable_local_apic < 0)
return -1;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
(boot_cpu_data.x86 == 15))
break;
goto no_apic;
case X86_VENDOR_INTEL:
if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
(boot_cpu_data.x86 == 5 && cpu_has_apic))
break;
goto no_apic;
default:
goto no_apic;
}
if (!cpu_has_apic) {
/*
* Over-ride BIOS and try to enable the local APIC only if
* "lapic" specified.
*/
if (enable_local_apic <= 0) {
printk(KERN_INFO "Local APIC disabled by BIOS -- "
"you can enable it with \"lapic\"\n");
return -1;
}
/*
* Some BIOSes disable the local APIC in the APIC_BASE
* MSR. This can only be done in software for Intel P6 or later
* and AMD K7 (Model > 1) or later.
*/
rdmsr(MSR_IA32_APICBASE, l, h);
if (!(l & MSR_IA32_APICBASE_ENABLE)) {
printk(KERN_INFO
"Local APIC disabled by BIOS -- reenabling.\n");
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
wrmsr(MSR_IA32_APICBASE, l, h);
enabled_via_apicbase = 1;
}
}
/*
* The APIC feature bit should now be enabled
* in `cpuid'
*/
features = cpuid_edx(1);
if (!(features & (1 << X86_FEATURE_APIC))) {
printk(KERN_WARNING "Could not enable APIC!\n");
return -1;
}
set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
/* The BIOS may have set up the APIC at some other address */
rdmsr(MSR_IA32_APICBASE, l, h);
if (l & MSR_IA32_APICBASE_ENABLE)
mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
if (nmi_watchdog != NMI_NONE && nmi_watchdog != NMI_DISABLED)
nmi_watchdog = NMI_LOCAL_APIC;
printk(KERN_INFO "Found and enabled local APIC!\n");
apic_pm_activate();
return 0;
no_apic:
printk(KERN_INFO "No local APIC present or hardware disabled\n");
return -1;
}
/**
* init_apic_mappings - initialize APIC mappings
*/
void __init init_apic_mappings(void)
{
/*
* If no local APIC can be found then set up a fake all
* zeroes page to simulate the local APIC and another
* one for the IO-APIC.
*/
if (!smp_found_config && detect_init_APIC()) {
apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
apic_phys = __pa(apic_phys);
} else
apic_phys = mp_lapic_addr;
set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
apic_phys);
/*
* Fetch the APIC ID of the BSP in case we have a
* default configuration (or the MP table is broken).
*/
if (boot_cpu_physical_apicid == -1U)
boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
#ifdef CONFIG_X86_IO_APIC
{
unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
int i;
for (i = 0; i < nr_ioapics; i++) {
if (smp_found_config) {
ioapic_phys = mp_ioapics[i].mpc_apicaddr;
if (!ioapic_phys) {
printk(KERN_ERR
"WARNING: bogus zero IO-APIC "
"address found in MPTABLE, "
"disabling IO/APIC support!\n");
smp_found_config = 0;
skip_ioapic_setup = 1;
goto fake_ioapic_page;
}
} else {
fake_ioapic_page:
ioapic_phys = (unsigned long)
alloc_bootmem_pages(PAGE_SIZE);
ioapic_phys = __pa(ioapic_phys);
}
set_fixmap_nocache(idx, ioapic_phys);
printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
__fix_to_virt(idx), ioapic_phys);
idx++;
}
}
#endif
}
/*
* This initializes the IO-APIC and APIC hardware if this is
* a UP kernel.
*/
int __init APIC_init_uniprocessor(void)
{
if (enable_local_apic < 0)
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
if (!smp_found_config && !cpu_has_apic)
return -1;
/*
* Complain if the BIOS pretends there is one.
*/
if (!cpu_has_apic &&
APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
boot_cpu_physical_apicid);
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
return -1;
}
verify_local_APIC();
connect_bsp_APIC();
/*
* Hack: In case of kdump, after a crash, kernel might be booting
* on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
* might be zero if read from MP tables. Get it from LAPIC.
*/
#ifdef CONFIG_CRASH_DUMP
boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
#endif
phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
setup_local_APIC();
#ifdef CONFIG_X86_IO_APIC
if (smp_found_config)
if (!skip_ioapic_setup && nr_ioapics)
setup_IO_APIC();
#endif
setup_boot_clock();
return 0;
}
/*
* Local APIC interrupts
*/
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
void smp_spurious_interrupt(struct pt_regs *regs)
{
unsigned long v;
irq_enter();
/*
* Check if this really is a spurious interrupt and ACK it
* if it is a vectored one. Just in case...
* Spurious interrupts should not be ACKed.
*/
v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
ack_APIC_irq();
/* see sw-dev-man vol 3, chapter 7.4.13.5 */
printk(KERN_INFO "spurious APIC interrupt on CPU#%d, "
"should never happen.\n", smp_processor_id());
x86: expand /proc/interrupts to include missing vectors, v2 Add missing IRQs and IRQ descriptions to /proc/interrupts. /proc/interrupts is most useful when it displays every IRQ vector in use by the system, not just those somebody thought would be interesting. This patch inserts the following vector displays to the i386 and x86_64 platforms, as appropriate: rescheduling interrupts TLB flush interrupts function call interrupts thermal event interrupts threshold interrupts spurious interrupts A threshold interrupt occurs when ECC memory correction is occuring at too high a frequency. Thresholds are used by the ECC hardware as occasional ECC failures are part of normal operation, but long sequences of ECC failures usually indicate a memory chip that is about to fail. Thermal event interrupts occur when a temperature threshold has been exceeded for some CPU chip. IIRC, a thermal interrupt is also generated when the temperature drops back to a normal level. A spurious interrupt is an interrupt that was raised then lowered by the device before it could be fully processed by the APIC. Hence the apic sees the interrupt but does not know what device it came from. For this case the APIC hardware will assume a vector of 0xff. Rescheduling, call, and TLB flush interrupts are sent from one CPU to another per the needs of the OS. Typically, their statistics would be used to discover if an interrupt flood of the given type has been occuring. AK: merged v2 and v4 which had some more tweaks AK: replace Local interrupts with Local timer interrupts AK: Fixed description of interrupt types. [ tglx: arch/x86 adaptation ] [ mingo: small cleanup ] Signed-off-by: Joe Korty <joe.korty@ccur.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Tim Hockin <thockin@hockin.org> Cc: Andi Kleen <ak@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 12:04:40 -04:00
__get_cpu_var(irq_stat).irq_spurious_count++;
irq_exit();
}
/*
* This interrupt should never happen with our APIC/SMP architecture
*/
void smp_error_interrupt(struct pt_regs *regs)
{
unsigned long v, v1;
irq_enter();
/* First tickle the hardware, only then report what went on. -- REW */
v = apic_read(APIC_ESR);
apic_write(APIC_ESR, 0);
v1 = apic_read(APIC_ESR);
ack_APIC_irq();
atomic_inc(&irq_err_count);
/* Here is what the APIC error bits mean:
0: Send CS error
1: Receive CS error
2: Send accept error
3: Receive accept error
4: Reserved
5: Send illegal vector
6: Received illegal vector
7: Illegal register address
*/
printk(KERN_DEBUG "APIC error on CPU%d: %02lx(%02lx)\n",
smp_processor_id(), v , v1);
irq_exit();
}
/*
* Initialize APIC interrupts
*/
void __init apic_intr_init(void)
{
#ifdef CONFIG_SMP
smp_intr_init();
#endif
/* self generated IPI for local APIC timer */
set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
/* IPI vectors for APIC spurious and error interrupts */
set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
/* thermal monitor LVT interrupt */
#ifdef CONFIG_X86_MCE_P4THERMAL
set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
#endif
}
/**
* connect_bsp_APIC - attach the APIC to the interrupt system
*/
void __init connect_bsp_APIC(void)
{
if (pic_mode) {
/*
* Do not trust the local APIC being empty at bootup.
*/
clear_local_APIC();
/*
* PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
* local APIC to INT and NMI lines.
*/
apic_printk(APIC_VERBOSE, "leaving PIC mode, "
"enabling APIC mode.\n");
outb(0x70, 0x22);
outb(0x01, 0x23);
}
enable_apic_mode();
}
/**
* disconnect_bsp_APIC - detach the APIC from the interrupt system
* @virt_wire_setup: indicates, whether virtual wire mode is selected
*
* Virtual wire mode is necessary to deliver legacy interrupts even when the
* APIC is disabled.
*/
void disconnect_bsp_APIC(int virt_wire_setup)
{
if (pic_mode) {
/*
* Put the board back into PIC mode (has an effect only on
* certain older boards). Note that APIC interrupts, including
* IPIs, won't work beyond this point! The only exception are
* INIT IPIs.
*/
apic_printk(APIC_VERBOSE, "disabling APIC mode, "
"entering PIC mode.\n");
outb(0x70, 0x22);
outb(0x00, 0x23);
} else {
/* Go back to Virtual Wire compatibility mode */
unsigned long value;
/* For the spurious interrupt use vector F, and enable it */
value = apic_read(APIC_SPIV);
value &= ~APIC_VECTOR_MASK;
value |= APIC_SPIV_APIC_ENABLED;
value |= 0xf;
apic_write_around(APIC_SPIV, value);
if (!virt_wire_setup) {
/*
* For LVT0 make it edge triggered, active high,
* external and enabled
*/
value = apic_read(APIC_LVT0);
value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
apic_write_around(APIC_LVT0, value);
} else {
/* Disable LVT0 */
apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
}
/*
* For LVT1 make it edge triggered, active high, nmi and
* enabled
*/
value = apic_read(APIC_LVT1);
value &= ~(
APIC_MODE_MASK | APIC_SEND_PENDING |
APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
apic_write_around(APIC_LVT1, value);
}
}
/*
* Power management
*/
#ifdef CONFIG_PM
static struct {
int active;
/* r/w apic fields */
unsigned int apic_id;
unsigned int apic_taskpri;
unsigned int apic_ldr;
unsigned int apic_dfr;
unsigned int apic_spiv;
unsigned int apic_lvtt;
unsigned int apic_lvtpc;
unsigned int apic_lvt0;
unsigned int apic_lvt1;
unsigned int apic_lvterr;
unsigned int apic_tmict;
unsigned int apic_tdcr;
unsigned int apic_thmr;
} apic_pm_state;
static int lapic_suspend(struct sys_device *dev, pm_message_t state)
{
unsigned long flags;
int maxlvt;
if (!apic_pm_state.active)
return 0;
maxlvt = lapic_get_maxlvt();
apic_pm_state.apic_id = apic_read(APIC_ID);
apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
apic_pm_state.apic_ldr = apic_read(APIC_LDR);
apic_pm_state.apic_dfr = apic_read(APIC_DFR);
apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
if (maxlvt >= 4)
apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
#ifdef CONFIG_X86_MCE_P4THERMAL
if (maxlvt >= 5)
apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
#endif
local_irq_save(flags);
disable_local_APIC();
local_irq_restore(flags);
return 0;
}
static int lapic_resume(struct sys_device *dev)
{
unsigned int l, h;
unsigned long flags;
int maxlvt;
if (!apic_pm_state.active)
return 0;
maxlvt = lapic_get_maxlvt();
local_irq_save(flags);
/*
* Make sure the APICBASE points to the right address
*
* FIXME! This will be wrong if we ever support suspend on
* SMP! We'll need to do this as part of the CPU restore!
*/
rdmsr(MSR_IA32_APICBASE, l, h);
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
wrmsr(MSR_IA32_APICBASE, l, h);
apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
apic_write(APIC_ID, apic_pm_state.apic_id);
apic_write(APIC_DFR, apic_pm_state.apic_dfr);
apic_write(APIC_LDR, apic_pm_state.apic_ldr);
apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
#ifdef CONFIG_X86_MCE_P4THERMAL
if (maxlvt >= 5)
apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
#endif
if (maxlvt >= 4)
apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
local_irq_restore(flags);
return 0;
}
/*
* This device has no shutdown method - fully functioning local APICs
* are needed on every CPU up until machine_halt/restart/poweroff.
*/
static struct sysdev_class lapic_sysclass = {
.name = "lapic",
.resume = lapic_resume,
.suspend = lapic_suspend,
};
static struct sys_device device_lapic = {
.id = 0,
.cls = &lapic_sysclass,
};
static void __devinit apic_pm_activate(void)
{
apic_pm_state.active = 1;
}
static int __init init_lapic_sysfs(void)
{
int error;
if (!cpu_has_apic)
return 0;
/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
error = sysdev_class_register(&lapic_sysclass);
if (!error)
error = sysdev_register(&device_lapic);
return error;
}
device_initcall(init_lapic_sysfs);
#else /* CONFIG_PM */
static void apic_pm_activate(void) { }
#endif /* CONFIG_PM */
/*
* APIC command line parameters
*/
static int __init parse_lapic(char *arg)
{
enable_local_apic = 1;
return 0;
}
early_param("lapic", parse_lapic);
static int __init parse_nolapic(char *arg)
{
enable_local_apic = -1;
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
return 0;
}
early_param("nolapic", parse_nolapic);
static int __init parse_disable_lapic_timer(char *arg)
{
local_apic_timer_disabled = 1;
return 0;
}
early_param("nolapic_timer", parse_disable_lapic_timer);
static int __init parse_lapic_timer_c2_ok(char *arg)
{
local_apic_timer_c2_ok = 1;
return 0;
}
early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
static int __init apic_set_verbosity(char *str)
{
if (strcmp("debug", str) == 0)
apic_verbosity = APIC_DEBUG;
else if (strcmp("verbose", str) == 0)
apic_verbosity = APIC_VERBOSE;
return 1;
}
__setup("apic=", apic_set_verbosity);