android_kernel_xiaomi_sm8350/arch/x86/kernel/cpu/amd.c
Venki Pallipadi 40fb17152c x86: support always running TSC on Intel CPUs
Impact: reward non-stop TSCs with good TSC-based clocksources, etc.

Add support for CPUID_0x80000007_Bit8 on Intel CPUs as well. This bit means
that the TSC is invariant with C/P/T states and always runs at constant
frequency.

With Intel CPUs, we have 3 classes
* CPUs where TSC runs at constant rate and does not stop n C-states
* CPUs where TSC runs at constant rate, but will stop in deep C-states
* CPUs where TSC rate will vary based on P/T-states and TSC will stop in deep
  C-states.

To cover these 3, one feature bit (CONSTANT_TSC) is not enough. So, add a
second bit (NONSTOP_TSC). CONSTANT_TSC indicates that the TSC runs at
constant frequency irrespective of P/T-states, and NONSTOP_TSC indicates
that TSC does not stop in deep C-states.

CPUID_0x8000000_Bit8 indicates both these feature bit can be set.
We still have CONSTANT_TSC _set_ and NONSTOP_TSC _not_set_ on some older Intel
CPUs, based on model checks. We can use TSC on such CPUs for time, as long as
those CPUs do not support/enter deep C-states.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 21:02:50 +01:00

479 lines
11 KiB
C

#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/mm.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/apic.h>
#ifdef CONFIG_X86_64
# include <asm/numa_64.h>
# include <asm/mmconfig.h>
# include <asm/cacheflush.h>
#endif
#include <mach_apic.h>
#include "cpu.h"
#ifdef CONFIG_X86_32
/*
* B step AMD K6 before B 9730xxxx have hardware bugs that can cause
* misexecution of code under Linux. Owners of such processors should
* contact AMD for precise details and a CPU swap.
*
* See http://www.multimania.com/poulot/k6bug.html
* http://www.amd.com/K6/k6docs/revgd.html
*
* The following test is erm.. interesting. AMD neglected to up
* the chip setting when fixing the bug but they also tweaked some
* performance at the same time..
*/
extern void vide(void);
__asm__(".align 4\nvide: ret");
static void __cpuinit init_amd_k5(struct cpuinfo_x86 *c)
{
/*
* General Systems BIOSen alias the cpu frequency registers
* of the Elan at 0x000df000. Unfortuantly, one of the Linux
* drivers subsequently pokes it, and changes the CPU speed.
* Workaround : Remove the unneeded alias.
*/
#define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
#define CBAR_ENB (0x80000000)
#define CBAR_KEY (0X000000CB)
if (c->x86_model == 9 || c->x86_model == 10) {
if (inl (CBAR) & CBAR_ENB)
outl (0 | CBAR_KEY, CBAR);
}
}
static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
{
u32 l, h;
int mbytes = num_physpages >> (20-PAGE_SHIFT);
if (c->x86_model < 6) {
/* Based on AMD doc 20734R - June 2000 */
if (c->x86_model == 0) {
clear_cpu_cap(c, X86_FEATURE_APIC);
set_cpu_cap(c, X86_FEATURE_PGE);
}
return;
}
if (c->x86_model == 6 && c->x86_mask == 1) {
const int K6_BUG_LOOP = 1000000;
int n;
void (*f_vide)(void);
unsigned long d, d2;
printk(KERN_INFO "AMD K6 stepping B detected - ");
/*
* It looks like AMD fixed the 2.6.2 bug and improved indirect
* calls at the same time.
*/
n = K6_BUG_LOOP;
f_vide = vide;
rdtscl(d);
while (n--)
f_vide();
rdtscl(d2);
d = d2-d;
if (d > 20*K6_BUG_LOOP)
printk("system stability may be impaired when more than 32 MB are used.\n");
else
printk("probably OK (after B9730xxxx).\n");
printk(KERN_INFO "Please see http://membres.lycos.fr/poulot/k6bug.html\n");
}
/* K6 with old style WHCR */
if (c->x86_model < 8 ||
(c->x86_model == 8 && c->x86_mask < 8)) {
/* We can only write allocate on the low 508Mb */
if (mbytes > 508)
mbytes = 508;
rdmsr(MSR_K6_WHCR, l, h);
if ((l&0x0000FFFF) == 0) {
unsigned long flags;
l = (1<<0)|((mbytes/4)<<1);
local_irq_save(flags);
wbinvd();
wrmsr(MSR_K6_WHCR, l, h);
local_irq_restore(flags);
printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
mbytes);
}
return;
}
if ((c->x86_model == 8 && c->x86_mask > 7) ||
c->x86_model == 9 || c->x86_model == 13) {
/* The more serious chips .. */
if (mbytes > 4092)
mbytes = 4092;
rdmsr(MSR_K6_WHCR, l, h);
if ((l&0xFFFF0000) == 0) {
unsigned long flags;
l = ((mbytes>>2)<<22)|(1<<16);
local_irq_save(flags);
wbinvd();
wrmsr(MSR_K6_WHCR, l, h);
local_irq_restore(flags);
printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
mbytes);
}
return;
}
if (c->x86_model == 10) {
/* AMD Geode LX is model 10 */
/* placeholder for any needed mods */
return;
}
}
static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
{
u32 l, h;
/*
* Bit 15 of Athlon specific MSR 15, needs to be 0
* to enable SSE on Palomino/Morgan/Barton CPU's.
* If the BIOS didn't enable it already, enable it here.
*/
if (c->x86_model >= 6 && c->x86_model <= 10) {
if (!cpu_has(c, X86_FEATURE_XMM)) {
printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
rdmsr(MSR_K7_HWCR, l, h);
l &= ~0x00008000;
wrmsr(MSR_K7_HWCR, l, h);
set_cpu_cap(c, X86_FEATURE_XMM);
}
}
/*
* It's been determined by AMD that Athlons since model 8 stepping 1
* are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
* As per AMD technical note 27212 0.2
*/
if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
rdmsr(MSR_K7_CLK_CTL, l, h);
if ((l & 0xfff00000) != 0x20000000) {
printk ("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n", l,
((l & 0x000fffff)|0x20000000));
wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
}
}
set_cpu_cap(c, X86_FEATURE_K7);
}
#endif
#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
static int __cpuinit nearby_node(int apicid)
{
int i, node;
for (i = apicid - 1; i >= 0; i--) {
node = apicid_to_node[i];
if (node != NUMA_NO_NODE && node_online(node))
return node;
}
for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
node = apicid_to_node[i];
if (node != NUMA_NO_NODE && node_online(node))
return node;
}
return first_node(node_online_map); /* Shouldn't happen */
}
#endif
/*
* On a AMD dual core setup the lower bits of the APIC id distingush the cores.
* Assumes number of cores is a power of two.
*/
static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_HT
unsigned bits;
bits = c->x86_coreid_bits;
/* Low order bits define the core id (index of core in socket) */
c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
/* Convert the initial APIC ID into the socket ID */
c->phys_proc_id = c->initial_apicid >> bits;
#endif
}
static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
{
#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
int cpu = smp_processor_id();
int node;
unsigned apicid = hard_smp_processor_id();
node = c->phys_proc_id;
if (apicid_to_node[apicid] != NUMA_NO_NODE)
node = apicid_to_node[apicid];
if (!node_online(node)) {
/* Two possibilities here:
- The CPU is missing memory and no node was created.
In that case try picking one from a nearby CPU
- The APIC IDs differ from the HyperTransport node IDs
which the K8 northbridge parsing fills in.
Assume they are all increased by a constant offset,
but in the same order as the HT nodeids.
If that doesn't result in a usable node fall back to the
path for the previous case. */
int ht_nodeid = c->initial_apicid;
if (ht_nodeid >= 0 &&
apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
node = apicid_to_node[ht_nodeid];
/* Pick a nearby node */
if (!node_online(node))
node = nearby_node(apicid);
}
numa_set_node(cpu, node);
printk(KERN_INFO "CPU %d/0x%x -> Node %d\n", cpu, apicid, node);
#endif
}
static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_HT
unsigned bits, ecx;
/* Multi core CPU? */
if (c->extended_cpuid_level < 0x80000008)
return;
ecx = cpuid_ecx(0x80000008);
c->x86_max_cores = (ecx & 0xff) + 1;
/* CPU telling us the core id bits shift? */
bits = (ecx >> 12) & 0xF;
/* Otherwise recompute */
if (bits == 0) {
while ((1 << bits) < c->x86_max_cores)
bits++;
}
c->x86_coreid_bits = bits;
#endif
}
static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
{
early_init_amd_mc(c);
/*
* c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
* with P/T states and does not stop in deep C-states
*/
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
}
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSCALL32);
#else
/* Set MTRR capability flag if appropriate */
if (c->x86 == 5)
if (c->x86_model == 13 || c->x86_model == 9 ||
(c->x86_model == 8 && c->x86_mask >= 8))
set_cpu_cap(c, X86_FEATURE_K6_MTRR);
#endif
}
static void __cpuinit init_amd(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_SMP
unsigned long long value;
/*
* Disable TLB flush filter by setting HWCR.FFDIS on K8
* bit 6 of msr C001_0015
*
* Errata 63 for SH-B3 steppings
* Errata 122 for all steppings (F+ have it disabled by default)
*/
if (c->x86 == 0xf) {
rdmsrl(MSR_K7_HWCR, value);
value |= 1 << 6;
wrmsrl(MSR_K7_HWCR, value);
}
#endif
early_init_amd(c);
/*
* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
* 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
*/
clear_cpu_cap(c, 0*32+31);
#ifdef CONFIG_X86_64
/* On C+ stepping K8 rep microcode works well for copy/memset */
if (c->x86 == 0xf) {
u32 level;
level = cpuid_eax(1);
if((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
}
if (c->x86 == 0x10 || c->x86 == 0x11)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
#else
/*
* FIXME: We should handle the K5 here. Set up the write
* range and also turn on MSR 83 bits 4 and 31 (write alloc,
* no bus pipeline)
*/
switch (c->x86) {
case 4:
init_amd_k5(c);
break;
case 5:
init_amd_k6(c);
break;
case 6: /* An Athlon/Duron */
init_amd_k7(c);
break;
}
/* K6s reports MCEs but don't actually have all the MSRs */
if (c->x86 < 6)
clear_cpu_cap(c, X86_FEATURE_MCE);
#endif
/* Enable workaround for FXSAVE leak */
if (c->x86 >= 6)
set_cpu_cap(c, X86_FEATURE_FXSAVE_LEAK);
if (!c->x86_model_id[0]) {
switch (c->x86) {
case 0xf:
/* Should distinguish Models here, but this is only
a fallback anyways. */
strcpy(c->x86_model_id, "Hammer");
break;
}
}
display_cacheinfo(c);
/* Multi core CPU? */
if (c->extended_cpuid_level >= 0x80000008) {
amd_detect_cmp(c);
srat_detect_node(c);
}
#ifdef CONFIG_X86_32
detect_ht(c);
#endif
if (c->extended_cpuid_level >= 0x80000006) {
if ((c->x86 >= 0x0f) && (cpuid_edx(0x80000006) & 0xf000))
num_cache_leaves = 4;
else
num_cache_leaves = 3;
}
if (c->x86 >= 0xf && c->x86 <= 0x11)
set_cpu_cap(c, X86_FEATURE_K8);
if (cpu_has_xmm2) {
/* MFENCE stops RDTSC speculation */
set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
}
#ifdef CONFIG_X86_64
if (c->x86 == 0x10) {
/* do this for boot cpu */
if (c == &boot_cpu_data)
check_enable_amd_mmconf_dmi();
fam10h_check_enable_mmcfg();
}
if (c == &boot_cpu_data && c->x86 >= 0xf && c->x86 <= 0x11) {
unsigned long long tseg;
/*
* Split up direct mapping around the TSEG SMM area.
* Don't do it for gbpages because there seems very little
* benefit in doing so.
*/
if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
printk(KERN_DEBUG "tseg: %010llx\n", tseg);
if ((tseg>>PMD_SHIFT) <
(max_low_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) ||
((tseg>>PMD_SHIFT) <
(max_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) &&
(tseg>>PMD_SHIFT) >= (1ULL<<(32 - PMD_SHIFT))))
set_memory_4k((unsigned long)__va(tseg), 1);
}
}
#endif
}
#ifdef CONFIG_X86_32
static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
{
/* AMD errata T13 (order #21922) */
if ((c->x86 == 6)) {
if (c->x86_model == 3 && c->x86_mask == 0) /* Duron Rev A0 */
size = 64;
if (c->x86_model == 4 &&
(c->x86_mask == 0 || c->x86_mask == 1)) /* Tbird rev A1/A2 */
size = 256;
}
return size;
}
#endif
static struct cpu_dev amd_cpu_dev __cpuinitdata = {
.c_vendor = "AMD",
.c_ident = { "AuthenticAMD" },
#ifdef CONFIG_X86_32
.c_models = {
{ .vendor = X86_VENDOR_AMD, .family = 4, .model_names =
{
[3] = "486 DX/2",
[7] = "486 DX/2-WB",
[8] = "486 DX/4",
[9] = "486 DX/4-WB",
[14] = "Am5x86-WT",
[15] = "Am5x86-WB"
}
},
},
.c_size_cache = amd_size_cache,
#endif
.c_early_init = early_init_amd,
.c_init = init_amd,
.c_x86_vendor = X86_VENDOR_AMD,
};
cpu_dev_register(amd_cpu_dev);