Linux invokes the AML _PDC method (Processor Driver Capabilities)
to tell the BIOS what features it can handle. While the ACPI
spec says nothing about the OS invoking _PDC multiple times,
doing so with changing bits seems to hopelessly confuse the BIOS
on multiple platforms up to and including crashing the system.
Factor out the _PDC invocation so Linux invokes it only once.
http://bugzilla.kernel.org/show_bug.cgi?id=5483
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
I recently picked up my older work to remove unnecessary #includes of
sched.h, starting from a patch by Dave Jones to not include sched.h
from module.h. This reduces the number of indirect includes of sched.h
by ~300. Another ~400 pointless direct includes can be removed after
this disentangling (patch to follow later).
However, quite a few indirect includes need to be fixed up for this.
In order to feed the patches through -mm with as little disturbance as
possible, I've split out the fixes I accumulated up to now (complete for
i386 and x86_64, more archs to follow later) and post them before the real
patch. This way this large part of the patch is kept simple with only
adding #includes, and all hunks are independent of each other. So if any
hunk rejects or gets in the way of other patches, just drop it. My scripts
will pick it up again in the next round.
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Not sure how it slipped by, but here's a trivial typo fix for powernow.
Signed-off-by: Chris Wright <chrisw@osdl.org>
[ It's "nurter" backwards.. Maybe we have a hillbilly The Shining fan? ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
AMD recently discovered that on some hardware, there is a race condition
possible when a C-state change request goes onto the bus at the same
time as a P-state change request.
Both requests happen, but the southbridge hardware only acknowledges the
C-state change. The PowerNow! driver is then stuck in a loop, waiting
for the P-state change acknowledgement. The driver eventually times
out, but can no longer perform P-state changes.
It turns out the solution is to resend the P-state change, which the
southbridge will acknowledge normally.
Thanks to Johannes Winkelmann for reporting this and testing the fix.
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Via reading the code, my understanding is that powernow-k8 uses
preempt_disable to ensure that driver->target doesn't migrate across cpus
whilst it's accessing per processor registers, however set_cpus_allowed
will provide this for us. Additionally, remove schedule() calls from
set_cpus_allowed as set_cpus_allowed ensures that you're executing on the
target processor on return.
Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
i386 Inline asm cleanup. Use cr/dr accessor functions.
Also, a potential bugfix. Also, some CR accessors really should be volatile.
Reads from CR0 (numeric state may change in an exception handler), writes to
CR4 (flipping CR4.TSD) and reads from CR2 (page fault) prevent instruction
re-ordering. I did not add memory clobber to CR3 / CR4 / CR0 updates, as it
was not there to begin with, and in no case should kernel memory be clobbered,
except when doing a TLB flush, which already has memory clobber.
I noticed that page invalidation does not have a memory clobber. I can't find
a bug as a result, but there is definitely a potential for a bug here:
#define __flush_tlb_single(addr) \
__asm__ __volatile__("invlpg %0": :"m" (*(char *) addr))
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Minor fallout from my upcoming __attribute__((format(printf,x,y)))
patches. The variable 'result' is untouched, so this patch just removes
it.
Signed-off-by: Mika Kukkonen <mikukkon@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Ho-hum, did not notice there was more printf fixes for cpufreq (you
should see the amount I have for isdn and reiser ...). Sorry for noise.
Signed-off-by: Mika Kukkonen <mikukkon@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
speedstep_centrino.c:extract_clock() assumes the bus speed of 100MHz, which is
not true with latest laptops. Due to this assumption and due to the encoded
frequency check during initialization, speedstep-centrino driver fails even
on systems that has proper ACPI information to do the P-state transition.
The change below moves the centrino-speedstep detection to be used only
when table based P-state transition is done. For ACPI based P-state
transition, we skip the centrino_cpu identification, and as a result we
don't use the bus speed assumption in extract_clock. This change makes
speedstep-centrino work on Pentium-M based systems, which have more than 100MHz
bus speed.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
The acpi-cpufreq driver does a P-state get after a P-state set
to verify whether set went through successfully. This test
is kind of redundant as set goes throught most of the times,
and the test is also expensive as a get of P-states can
take a lot of time (same as a set operation) as it goes
through SMM mode. Effectively, we are doubling the P-state
latency due to this get opertion.
momdule parameter "acpi_pstate_strict" restores orginal paranoia.
http://bugzilla.kernel.org/show_bug.cgi?id=5129
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Otherwise a platform that supports ACPI based cpufreq
and boots up at lowest possible speed could stay there
forever. This because the governor may request max speed,
but the code doesn't update if there is no change in
speed, and it assumed the initial state of max speed.
http://bugzilla.kernel.org/show_bug.cgi?id=4634
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:740: warning: unused variable `vid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:739: warning: unused variable `fid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:743: warning: unused variable `vid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:742: warning: unused variable `fid'
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:746: `fid' undeclared (first use in this function)
arch/i386/kernel/cpu/cpufreq/powernow-k8.c:746: `vid' undeclared (first use in this function)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
powernow-k8.c:110: warning: `hi' may be used uninitialized in this function
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
can be encoded in the current driver's 4 bit frequency
field. This patch updates the driver to support Rev F
including 6 bit FIDs and processor ID updates.
This should apply cleanly whether or not the dual-core
bugfix I sent out last week is applied. I'd prefer
that both get applied, of course.
Signed-off-by: David Keck <david.keck@amd.com>
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
each core be created in the _cpu_init function
call. The cpufreq infrastructure doesn't call
_cpu_init for the second core in each processor.
Some systems crashed when _get was called with
an odd-numbered core because it tried to
dereference a NULL pointer since the data
structure had not been created.
The attached patch solves the problem by
initializing data structures for all shared
cores in the _cpu_init function. It should
apply to 2.6.12-rc6 and has been tested by
AMD and Sun.
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
powernow-k8.c: In function `query_current_values_with_pending_wait':
powernow-k8.c:110: warning: `hi' may be used uninitialized in this function
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Venkatesh Pallipadi
Linus Torvalds
Tobias Klauser
Tim Schmielau
Chris Wright
Dave Jones
Len Brown
Zachary Amsden
Mika Kukkonen
Dominik Brodowski
Brian Gerst