This allows debugging of problems which happen eary in the kernel
boot process (after bootargs are parsed, but before serial subsystem
is fully initialized)
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Since this boot-time option was removed in commit
9ab7e323af, delete the reference to it.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Since this boot-time option was removed in commit
9ab7e323af, delete the reference to it.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
In MPS mode, "nosmp" and "maxcpus=0" boot a UP kernel with IOAPIC disabled.
However, in ACPI mode, these parameters didn't completely disable
the IO APIC initialization code and boot failed.
init/main.c:
Disable the IO_APIC if "nosmp" or "maxcpus=0"
undefine disable_ioapic_setup() when it doesn't apply.
i386:
delete ioapic_setup(), it was a duplicate of parse_noapic()
delete undefinition of disable_ioapic_setup()
x86_64:
rename disable_ioapic_setup() to parse_noapic() to match i386
define disable_ioapic_setup() in header to match i386
http://bugzilla.kernel.org/show_bug.cgi?id=1641
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Some hardware will malfunction at a temperature below
the BIOS provided critical shutdown threshold.
This hook allows moving the critical trip points down
to a temperature which provokes a graceful shutdown
before the hardware malfunction.
http://bugzilla.kernel.org/show_bug.cgi?id=8884
WARNING: A trip-point override will not get noticed
until the system delivers a temperature change event,
or unless thermal zone polling is enabled.
eg. "thermal.tzp=10"
Signed-off-by: Len Brown <len.brown@intel.com>
thermal.act=-1 disables all active trip points
in all ACPI thermal zones.
thermal.act=C, where C > 0, overrides all lowest temperature
active trip points in all thermal zones to C degrees Celsius.
Raising this trip-point may allow you to keep your system silent
up to a higher temperature. However, it will not allow you to
raise the lowest temperature trip point above the next higher
trip point (if there is one). Lowering this trip point may
kick in the fan sooner.
Note that overriding this trip-point will disable any BIOS attempts
to implement hysteresis around the lowest temperature trip point.
This may result in the fan starting and stopping frequently
if temperature frequently crosses C.
WARNING: raising trip points above the manufacturer's defaults
may cause the system to run at higher temperature and shorten
its life.
Signed-off-by: Len Brown <len.brown@intel.com>
thermal.nocrt=1 disables actions on _CRT and _HOT
ACPI thermal zone trip-points. They will be marked
as <disabled> in /proc/acpi/thermal_zone/*/trip_points.
There are two cases where this option is used:
1. Debugging a hot system crossing valid trip point.
If your system fan is spinning at full speed,
be sure that the vent is not clogged with dust.
Many laptops have very fine thermal fins that are easily blocked.
Check that the processor fan-sink is properly seated,
has the proper thermal grease, and is really spinning.
Check for fan related options in BIOS SETUP.
Sometimes there is a performance vs quiet option.
Defaults are generally the most conservative.
If your fan is not spinning, yet /proc/acpi/fan/
has files in it, please file a Linux/ACPI bug.
WARNING: you risk shortening the lifetime of your
hardware if you use this parameter on a hot system.
Note that this refers to all system components,
including the disk drive.
2. Working around a cool system crossing critical
trip point due to erroneous temperature reading.
Try again with CONFIG_HWMON=n
There is known potential for conflict between the
the hwmon sub-system and the ACPI BIOS.
If this fixes it, notify lm-sensors@lm-sensors.org
and linux-acpi@vger.kernel.org
Otherwise, file a Linux/ACPI bug, or notify
just linux-acpi@vger.kernel.org.
Signed-off-by: Len Brown <len.brown@intel.com>
"thermal.psv=-1" disables passive trip points
for all ACPI thermal zones.
"thermal.psv=C", where 'C' is degrees Celsius,
overrides all existing passive trip points
for all ACPI thermal zones.
thermal.psv is checked at module load time,
and in response to trip-point change events.
Note that if the system does not deliver thermal zone
temperature change events near the new trip-point,
then it will not be noticed. To force your custom
trip point to be noticed, you may need to enable polling:
eg. thermal.tzp=3000 invokes polling every 5 minutes.
Note that once passive thermal throttling is invoked,
it has its own internal Thermal Sampling Period (_TSP),
that is unrelated to _TZP.
WARNING: disabling or raising a thermal trip point
may result in increased running temperature and
shorter hardware lifetime on some systems.
Signed-off-by: Len Brown <len.brown@intel.com>
Thermal Zone Polling frequency (_TZP) is an optional ACPI object
recommending the rate that the OS should poll the associated thermal zone.
If _TZP is 0, no polling should be used.
If _TZP is non-zero, then the platform recommends that
the OS poll the thermal zone at the specified rate.
The minimum period is 30 seconds.
The maximum period is 5 minutes.
(note _TZP and thermal.tzp units are in deci-seconds,
so _TZP = 300 corresponds to 30 seconds)
If _TZP is not present, ACPI 3.0b recommends that the
thermal zone be polled at an "OS provided default frequency".
However, common industry practice is:
1. The BIOS never specifies any _TZP
2. High volume OS's from this century never poll any thermal zones
Ie. The OS depends on the platform's ability to
provoke thermal events when necessary, and
the "OS provided default frequency" is "never":-)
There is a proposal that ACPI 4.0 be updated to reflect
common industry practice -- ie. no _TZP, no polling.
The Linux kernel already follows this practice --
thermal zones are not polled unless _TZP is present and non-zero.
But thermal zone polling is useful as a workaround for systems
which have ACPI thermal control, but have an issue preventing
thermal events. Indeed, some Linux distributions still
set a non-zero thermal polling frequency for this reason.
But rather than ask the user to write a polling frequency
into all the /proc/acpi/thermal_zone/*/polling_frequency
files, here we simply document and expose the already
existing module parameter to do the same at system level,
to simplify debugging those broken platforms.
Note that thermal.tzp is a module-load time parameter only.
Signed-off-by: Len Brown <len.brown@intel.com>
"thermal.off=1" disables all ACPI thermal support at boot time.
CONFIG_ACPI_THERMAL=n can do this at build time.
"# rmmod thermal" can do this at run time,
as long as thermal is built as a module.
WARNING: On some systems, disabling ACPI thermal support
will cause the system to run hotter and reduce the
lifetime of the hardware.
Signed-off-by: Len Brown <len.brown@intel.com>
Documentation/watchdog/watchdog.txt does not exist, it is Documentation/watchdog/wdt.txt
Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert 7e92b4fc34. It broke Sébastien Dugué's
machine and Jeff said (persuasively)
This seems like it will break decades-long-working stuff, in favor of
breaking new ground in our favorite area, "trusting the BIOS."
It's just not worth it for serial ports, IMO. Serial ports are something
that just shouldn't break at this late stage in the game. My new Intel
platform boxes don't even have serial ports, so I question the value of
messing with serial port probing even more... because... just wait a year,
and your box won't have a serial port either! :)
I certainly don't object to the use of platform devices (or isa_driver),
but the probe change seems questionable. That's sorta analagous to
rewriting the floppy driver probe routine. Sure you could do it... but why
risk all that damage and go through debugging all over again?
It seems clear from this report that we cannot, should not, trust BIOS for
something (a) so simple and (b) that has been working for over a decade.
Much discussion ensued and we've decided to have another go at all of this.
Cc: Sébastien Dugué <sebastien.dugue@bull.net>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Cc: Sascha Sommer <saschasommer@freenet.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"acpi_no_auto_ssdt" prevents Linux from automatically loading
all the SSDTs listed in the RSDT/XSDT.
This is needed for debugging. In particular,
it allows a DSDT override to optionally be a DSDT+SSDT override.
http://bugzilla.kernel.org/show_bug.cgi?id=3774
Signed-off-by: Len Brown <len.brown@intel.com>
This implements new vDSO for x86-64. The concept is similar
to the existing vDSOs on i386 and PPC. x86-64 has had static
vsyscalls before, but these are not flexible enough anymore.
A vDSO is a ELF shared library supplied by the kernel that is mapped into
user address space. The vDSO mapping is randomized for each process
for security reasons.
Doing this was needed for clock_gettime, because clock_gettime
always needs a syscall fallback and having one at a fixed
address would have made buffer overflow exploits too easy to write.
The vdso can be disabled with vdso=0
It currently includes a new gettimeofday implemention and optimized
clock_gettime(). The gettimeofday implementation is slightly faster
than the one in the old vsyscall. clock_gettime is significantly faster
than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME.
The new calls are generally faster than the old vsyscall.
Advantages over the old x86-64 vsyscalls:
- Extensible
- Randomized
- Cleaner
- Easier to virtualize (the old static address range previously causes
overhead e.g. for Xen because it has to create special page tables for it)
Weak points:
- glibc support still to be written
The VM interface is partly based on Ingo Molnar's i386 version.
Includes compile fix from Joachim Deguara
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a merge of Peter Keilty's initial patch (which was
revived by Bob Picco) for this with Hidetoshi Seto's fixes
and scaling improvements.
Acked-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch adds a new parameter for sizing ZONE_MOVABLE called
movablecore=. While kernelcore= is used to specify the minimum amount of
memory that must be available for all allocation types, movablecore= is
used to specify the minimum amount of memory that is used for migratable
allocations. The amount of memory used for migratable allocations
determines how large the huge page pool could be dynamically resized to at
runtime for example.
How movablecore is actually handled is that the total number of pages in
the system is calculated and a value is set for kernelcore that is
kernelcore == totalpages - movablecore
Both kernelcore= and movablecore= can be safely specified at the same time.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds the kernelcore= parameter for x86.
Once all patches are applied, a new command-line parameter exist and a new
sysctl. This patch adds the necessary documentation.
From: Yasunori Goto <y-goto@jp.fujitsu.com>
When "kernelcore" boot option is specified, kernel can't boot up on ia64
because of an infinite loop. In addition, the parsing code can be handled
in an architecture-independent manner.
This patch uses common code to handle the kernelcore= parameter. It is
only available to architectures that support arch-independent zone-sizing
(i.e. define CONFIG_ARCH_POPULATES_NODE_MAP). Other architectures will
ignore the boot parameter.
[bunk@stusta.de: make cmdline_parse_kernelcore() static]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add per-CPU vector domain support for IA64_GENERIC. It is enabled by
adding the "vector=percpu" boot option.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
* 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block:
splice: direct splicing updates ppos twice
more ACSI removal
umem: Fix match of pci_ids in umem driver
umem: Remove references to dead CONFIG_MM_MAP_MEMORY variable
remove the documentation for the legacy CDROM drivers
It's useful sometimes to disable the softlockup checker at boottime.
Especially if it triggers during a distro install.
Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some buses (e.g. USB and MMC) do their scanning of devices in the
background, causing a race between them and prepare_namespace(). In order
to be able to use these buses without an initrd, we now wait for the device
specified in root= to actually show up.
If the device never shows up than we will hang in an infinite loop. In
order to not mess with setups that reboot on panic, the feature must be
turned on via the command line option "rootwait".
[bunk@stusta.de: root_wait can become static]
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow printk_time to be enabled or disabled at boot time. Previously it
could be enabled only, but not disabled.
Change printk_time from an int to a bool since that's what it is. Make its
logical (exposed) name just be "time" (was "printk_time").
Note: Changes kernel boot option syntax from "time" to "printk.time=value".
Since printk_time is declared as a module_param, it can also be
changed at run-time by modifying
/sys/module/printk/parameters/time
to a value of 1/Y/y to enabled it or 0/N/n to disable it.
Since printk_time is declared as a module_param, its value can also
be set at boot-time by using
linux printk.time=<bool>
If the "time" boot option is used, print a message that it is deprecated
and will be removed.
Note its planned removal in feature-removal-schedule.txt.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the print-fatal-signals=1 boot option and the
/proc/sys/kernel/print-fatal-signals runtime switch.
This feature prints some minimal information about userspace segfaults to
the kernel console. This is useful to find early bootup bugs where
userspace debugging is very hard.
Defaults to off.
[akpm@linux-foundation.org: Don't add new sysctl numbers]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch contains the scheduled removal of OSS drivers that:
- have ALSA drivers for the same hardware without known regressions and
- whose Kconfig options have been removed in 2.6.20.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new configuration variable
CONFIG_SLUB_DEBUG_ON
If set then the kernel will be booted by default with slab debugging
switched on. Similar to CONFIG_SLAB_DEBUG. By default slab debugging
is available but must be enabled by specifying "slub_debug" as a
kernel parameter.
Also add support to switch off slab debugging for a kernel that was
built with CONFIG_SLUB_DEBUG_ON. This works by specifying
slub_debug=-
as a kernel parameter.
Dave Jones wanted this feature.
http://marc.info/?l=linux-kernel&m=118072189913045&w=2
[akpm@linux-foundation.org: clean up switch statement]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make zonelist creation policy selectable from sysctl/boot option v6.
This patch makes NUMA's zonelist (of pgdat) order selectable.
Available order are Default(automatic)/ Node-based / Zone-based.
[Default Order]
The kernel selects Node-based or Zone-based order automatically.
[Node-based Order]
This policy treats the locality of memory as the most important parameter.
Zonelist order is created by each zone's locality. This means lower zones
(ex. ZONE_DMA) can be used before higher zone (ex. ZONE_NORMAL) exhausion.
IOW. ZONE_DMA will be in the middle of zonelist.
current 2.6.21 kernel uses this.
Pros.
* A user can expect local memory as much as possible.
Cons.
* lower zone will be exhansted before higher zone. This may cause OOM_KILL.
Maybe suitable if ZONE_DMA is relatively big and you never see OOM_KILL
because of ZONE_DMA exhaution and you need the best locality.
(example)
assume 2 node NUMA. node(0) has ZONE_DMA/ZONE_NORMAL, node(1) has ZONE_NORMAL.
*node(0)'s memory allocation order:
node(0)'s NORMAL -> node(0)'s DMA -> node(1)'s NORMAL.
*node(1)'s memory allocation order:
node(1)'s NORMAL -> node(0)'s NORMAL -> node(0)'s DMA.
[Zone-based order]
This policy treats the zone type as the most important parameter.
Zonelist order is created by zone-type order. This means lower zone
never be used bofere higher zone exhaustion.
IOW. ZONE_DMA will be always at the tail of zonelist.
Pros.
* OOM_KILL(bacause of lower zone) occurs only if the whole zones are exhausted.
Cons.
* memory locality may not be best.
(example)
assume 2 node NUMA. node(0) has ZONE_DMA/ZONE_NORMAL, node(1) has ZONE_NORMAL.
*node(0)'s memory allocation order:
node(0)'s NORMAL -> node(1)'s NORMAL -> node(0)'s DMA.
*node(1)'s memory allocation order:
node(1)'s NORMAL -> node(0)'s NORMAL -> node(0)'s DMA.
bootoption "numa_zonelist_order=" and proc/sysctl is supporetd.
command:
%echo N > /proc/sys/vm/numa_zonelist_order
Will rebuild zonelist in Node-based order.
command:
%echo Z > /proc/sys/vm/numa_zonelist_order
Will rebuild zonelist in Zone-based order.
Thanks to Lee Schermerhorn, he gives me much help and codes.
[Lee.Schermerhorn@hp.com: add check_highest_zone to build_zonelists_in_zone_order]
[akpm@linux-foundation.org: build fix]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "jesse.barnes@intel.com" <jesse.barnes@intel.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Beacuse SERIAL_PORT_DFNS is removed from include/asm-i386/serial.h and
include/asm-x86_64/serial.h. the serial8250_ports need to be probed late in
serial initializing stage. the console_init=>serial8250_console_init=>
register_console=>serial8250_console_setup will return -ENDEV, and console
ttyS0 can not be enabled at that time. need to wait till uart_add_one_port in
drivers/serial/serial_core.c to call register_console to get console ttyS0.
that is too late.
Make early_uart to use early_param, so uart console can be used earlier. Make
it to be bootconsole with CON_BOOT flag, so can use console handover feature.
and it will switch to corresponding normal serial console automatically.
new command line will be:
console=uart8250,io,0x3f8,9600n8
console=uart8250,mmio,0xff5e0000,115200n8
or
earlycon=uart8250,io,0x3f8,9600n8
earlycon=uart8250,mmio,0xff5e0000,115200n8
it will print in very early stage:
Early serial console at I/O port 0x3f8 (options '9600n8')
console [uart0] enabled
later for console it will print:
console handover: boot [uart0] -> real [ttyS0]
Signed-off-by: <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes the documentation for the removed legacy CDROM drivers.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
the SMP load-balancer uses the boot-time migration-cost estimation
code to attempt to improve the quality of balancing. The reason for
this code is that the discrete priority queues do not preserve
the order of scheduling accurately, so the load-balancer skips
tasks that were running on a CPU 'recently'.
this code is fundamental fragile: the boot-time migration cost detector
doesnt really work on systems that had large L3 caches, it caused boot
delays on large systems and the whole cache-hot concept made the
balancing code pretty undeterministic as well.
(and hey, i wrote most of it, so i can say it out loud that it sucks ;-)
under CFS the same purpose of cache affinity can be achieved without
any special cache-hot special-case: tasks are sorted in the 'timeline'
tree and the SMP balancer picks tasks from the left side of the
tree, thus the most cache-cold task is balanced automatically.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This looks like leftover text in the kernel parameter in documentation.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update documentation to describe how to read a SLUB error report.
Add slub parameters to Documentation/kernel-parameters.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The boot option "acpi_osi=" has always disabled Linux _OSI support,
thus disabling all OS Interface strings which are advertised
by Linux to the BIOS.
Now...
acpi_osi="string" adds the interface string, and
acpi_osi="!string" invalidates the pre-defined interface string
eg. acpi_osi="!Windows 2006"
would disable Linux's claim of Vista compatibility.
Signed-off-by: Len Brown <len.brown@intel.com>
Document the available clocksources per platform and move clocksource= into
the correct (alpha) location in the file.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Looks like you removed the combined_mode quirk (yay!) but didn't update
kernel-parameters.txt... might confuse people. Here's a patch to remove
mention of it from the documentation.
Signed-off-by: Jesse Barnes <jesse.barnes@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add description to Documentation/kernel-parameters.txt on new options
default_blue, default_grn, default_red, and default_utf8.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make x86 COM ports into platform devices and don't probe for them
if we have PNP.
This prevents double discovery, where a device was found both by
the legacy probe and by 8250_pnp, e.g.,
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:02: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
This also means IRDA devices without a UART PNP ID will no longer be
claimed by the serial driver, which might require changes in IRDA
drivers and administration.
In addition to this patch, you may need to configure a setserial init
script, e.g., /etc/init.d/setserial, so it doesn't poke legacy UART
stuff back in. On Debian, "dpkg-reconfigure setserial" with the "kernel"
option does this.
To force the old legacy probe behavior even when we have PNPBIOS or
ACPI, load the new legacy_serial module (or build 8250 static) with
the "legacy_serial.force" option.
[akpm@linux-foundation.org: fix makefiles]
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Keith Owens <kaos@ocs.com.au>
Cc: Len Brown <lenb@kernel.org>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Ville Syrjala <syrjala@sci.fi>
Cc: Russell King <rmk+serial@arm.linux.org.uk>
Cc: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Claim devices using PNP, unless the user explicitly specified device
addresses. This can be disabled with the "smsc-ircc2.nopnp" option.
This removes the need for probing legacy addresses and helps untangle IR
devices from serial8250 devices.
Sometimes the SMC device is at a legacy COM port address but does not use the
legacy COM IRQ. In this case, claiming the device using PNP rather than 8250
legacy probe means we can automatically use the correct IRQ rather than
forcing the user to use "setserial" to set the IRQ manually.
If the PNP claim doesn't work, make sure you don't have a setserial init
script, e.g., /etc/init.d/setserial, configured to poke in legacy COM port
resources for the IRDA device. That causes the serial driver to claim
resources needed by this driver.
Based on this patch by Ville Syrjälä:
http://www.hpl.hp.com/personal/Jean_Tourrilhes/IrDA/ir260_smsc_pnp.diff
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Keith Owens <kaos@ocs.com.au>
Cc: Len Brown <lenb@kernel.org>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Jean Tourrilhes <jt@hpl.hp.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Ville Syrjala <syrjala@sci.fi>
Cc: Russell King <rmk+serial@arm.linux.org.uk>
Acked-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It doesn't put the CPU into deeper sleep states, so it's better to use the standard
idle loop to save power. But allow to reenable it anyways for benchmarking.
I also removed the obsolete idle=halt on i386
Cc: andreas.herrmann@amd.com
Signed-off-by: Andi Kleen <ak@suse.de>
