Commit Graph

25594 Commits

Author SHA1 Message Date
Paul Mundt 5840263ecb sh: Don't enable clockevents broadcasting on UP SH-X3 builds.
Fixes up compile errors with missing timer definitions. It's pointless to
have this enabled anyways if CONFIG_SMP=n.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:04 +09:00
Paul Mundt fa43972fab sh: fixup many sparse errors.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:04 +09:00
Paul Mundt 7d96169cb7 sh: Display CPU information in show_regs().
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:03 +09:00
Paul Mundt 53c01d2dc3 sh: Early dummy clockevent registration on boot CPU.
The dummy timer needs to be registered on the boot CPU before the
system timer clockevent is registered, or broadcasting doesn't work
as advertized.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:03 +09:00
Paul Mundt 71f0bdcab6 sh: smp: shove a cpu_relax() in the plat_start_cpu() busy loop.
Without this, certain versions of GCC will happily optimize the entire
loop out.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:03 +09:00
Paul Mundt 8c24594dea sh: generic clockevent broadcast support.
This hooks up GENERIC_CLOCKEVENTS_BROADCAST and a dummy local timer,
which we call in to from the timer IPI when no other local timer is
provided.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:03 +09:00
Paul Mundt 6f52707e68 sh: smp: Hook up a timer IPI stub.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:03 +09:00
Paul Mundt c7936b9abc sh: smp: Hook in to the generic IPI handler for SH-X3 SMP.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:03 +09:00
Paul Mundt 173a44dd1f sh: smp: Provide a generic IPI handler.
This provides a generic smp_message_recv() routine (based on the PPC
one), that IPI IRQs can wrap in to.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:02 +09:00
Paul Mundt 04ec080dca sh: Kill off unused defines from asm/smp.h.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:02 +09:00
Paul Mundt ee43a8442b sh: Provide movli.l/movco.l-based cmpxchg.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:02 +09:00
Paul Mundt 742fd1bcfb sh: Provide movli.l/movco.l-based bitops.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-08 10:35:02 +09:00
Linus Torvalds 64f996f670 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: cpu_init(): fix memory leak when using CPU hotplug
  x86: pda_init(): fix memory leak when using CPU hotplug
  x86, xen: Use native_pte_flags instead of native_pte_val for .pte_flags
  x86: move mtrr cpu cap setting early in early_init_xxxx
  x86: delay early cpu initialization until cpuid is done
  x86: use X86_FEATURE_NOPL in alternatives
  x86: add NOPL as a synthetic CPU feature bit
  x86: boot: stub out unimplemented CPU feature words
2008-09-06 19:36:23 -07:00
Linus Torvalds f532522565 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  clocksource, acpi_pm.c: check for monotonicity
  clocksource, acpi_pm.c: use proper read function also in errata mode
  ntp: fix calculation of the next jiffie to trigger RTC sync
  x86: HPET: read back compare register before reading counter
  x86: HPET fix moronic 32/64bit thinko
  clockevents: broadcast fixup possible waiters
  HPET: make minimum reprogramming delta useful
  clockevents: prevent endless loop lockup
  clockevents: prevent multiple init/shutdown
  clockevents: enforce reprogram in oneshot setup
  clockevents: prevent endless loop in periodic broadcast handler
  clockevents: prevent clockevent event_handler ending up handler_noop
2008-09-06 19:33:26 -07:00
Linus Torvalds a22a9a90cf Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  [MIPS] Probe initrd header only if explicitly specified
  [MIPS] TX39xx: Add missing local_flush_icache_range initialization
  [MIPS] TXx9: Fix txx9_pcode initialization
  [MIPS] Fix WARNING: at kernel/smp.c:290
  [MIPS] Fix data bus error recovery
2008-09-06 19:32:21 -07:00
Andreas Herrmann 23952a96ae x86: cpu_init(): fix memory leak when using CPU hotplug
Exception stacks are allocated each time a CPU is set online.
But the allocated space is never freed. Thus with one CPU hotplug
offline/online cycle there is a memory leak of 24K (6 pages) for
a CPU.

Fix is to allocate exception stacks only once -- when the CPU is
set online for the first time.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 20:48:16 +02:00
Andreas Herrmann d04ec773d7 x86: pda_init(): fix memory leak when using CPU hotplug
pda->irqstackptr is allocated whenever a CPU is set online.
But it is never freed. This results in a memory leak of 16K
for each CPU offline/online cycle.

Fix is to allocate pda->irqstackptr only once.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 20:48:02 +02:00
Eduardo Habkost e4a6be4d28 x86, xen: Use native_pte_flags instead of native_pte_val for .pte_flags
Using native_pte_val triggers the BUG_ON() in the paravirt_ops
version of pte_flags().

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 20:13:58 +02:00
Yinghai Lu dd786dd12c x86: move mtrr cpu cap setting early in early_init_xxxx
Krzysztof Helt found MTRR is not detected on k6-2

root cause:
	we moved mtrr_bp_init() early for mtrr trimming,
and in early_detect we only read the CPU capability from cpuid,
so some cpu doesn't have that bit in cpuid.

So we need to add early_init_xxxx to preset those bit before mtrr_bp_init
for those earlier cpus.

this patch is for v2.6.27

Reported-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 17:50:55 +02:00
Krzysztof Helt 12cf105cd6 x86: delay early cpu initialization until cpuid is done
Move early cpu initialization after cpu early get cap so the
early cpu initialization can fix up cpu caps.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 17:50:38 +02:00
Thomas Gleixner 72d43d9bc9 x86: HPET: read back compare register before reading counter
After fixing the u32 thinko I sill had occasional hickups on ATI chipsets
with small deltas. There seems to be a delay between writing the compare
register and the transffer to the internal register which triggers the
interrupt. Reading back the value makes sure, that it hit the internal
match register befor we compare against the counter value.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-09-06 07:21:17 +02:00
Thomas Gleixner f7676254f1 x86: HPET fix moronic 32/64bit thinko
We use the HPET only in 32bit mode because:
1) some HPETs are 32bit only
2) on i386 there is no way to read/write the HPET atomic 64bit wide

The HPET code unification done by the "moron of the year" did
not take into account that unsigned long is different on 32 and
64 bit.

This thinko results in a possible endless loop in the clockevents
code, when the return comparison fails due to the 64bit/332bit
unawareness. 

unsigned long cnt = (u32) hpet_read() + delta can wrap over 32bit.
but the final compare will fail and return -ETIME causing endless
loops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-09-06 07:21:17 +02:00
H. Peter Anvin f31d731e44 x86: use X86_FEATURE_NOPL in alternatives
Use X86_FEATURE_NOPL to determine if it is safe to use P6 NOPs in
alternatives.  Also, replace table and loop with simple if statement.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-09-05 16:14:01 -07:00
H. Peter Anvin b6734c35af x86: add NOPL as a synthetic CPU feature bit
The long noops ("NOPL") are supposed to be detected by family >= 6.
Unfortunately, several non-Intel x86 implementations, both hardware
and software, don't obey this dictum.  Instead, probe for NOPL
directly by executing a NOPL instruction and see if we get #UD.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-09-05 16:13:52 -07:00
H. Peter Anvin b74b06c5f6 x86: boot: stub out unimplemented CPU feature words
The CPU feature detection code in the boot code is somewhat minimal,
and doesn't include all possible CPUID words.  In particular, it
doesn't contain the code for CPU feature words 2 (Transmeta),
3 (Linux-specific), 5 (VIA), or 7 (scattered).  Zero them out, so we
can still set those bits as known at compile time; in particular, this
allows creating a Linux-specific NOPL flag and have it required (and
therefore resolvable at compile time) in 64-bit mode.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-09-05 16:13:44 -07:00
Linus Torvalds 1c402c8cd1 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: add io delay quirk for Presario F700
2008-09-05 14:36:21 -07:00
Linus Torvalds 6f74b1849b Merge git://git.infradead.org/~dwmw2/dwmw2-2.6.27
* git://git.infradead.org/~dwmw2/dwmw2-2.6.27:
  Revert "[ARM] use the new byteorder headers"
  Fix conditional export of kvh.h and a.out.h to userspace.
  [MTD] [NAND] tmio_nand: fix base address programming
2008-09-05 14:31:54 -07:00
Linus Torvalds b693ffe673 Merge branch 'sh/for-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* 'sh/for-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  i2c: fix i2c-sh_mobile timing issues
  sh64: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
  sh: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
  sh: fix semtimedop syscall
  sh: update AP325RXA defconfig
  sh: update Migo-R defconfig
  sh: fix platform_resource_setup_memory() section mismatch
  sh: fix kexec entry point for crash kernels
  sh: crash kernel resource fix
  sh: fix ptrace_64.c:user_disable_single_step()
  sh64: re-add the __strnlen_user() prototype
2008-09-05 14:30:58 -07:00
Atsushi Nemoto 0011036bee [MIPS] Probe initrd header only if explicitly specified
Currently init_initrd() probes initrd header at the last page of kernel
image, but it is valid only if addinitrd was used.  If addinitrd was not
used, the area contains garbage so probing there might misdetect initrd
header (magic number is not strictly robust).

This patch introduces CONFIG_PROBE_INITRD_HEADER to explicitly enable this
probing.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-09-05 21:24:12 +01:00
Atsushi Nemoto 3885ec8ca2 [MIPS] TX39xx: Add missing local_flush_icache_range initialization
Commmit 59e39ecd933ba49eb6efe84cbfa5597a6c9ef18a ("Fix WARNING: at
kernel/smp.c:290") introduced local_flush_icache_range but lacks
initialization for some TX39 case.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-09-05 21:24:12 +01:00
Atsushi Nemoto 073828d078 [MIPS] TXx9: Fix txx9_pcode initialization
The txx9_pcode variable was introduced in commit
fe1c2bc64f65003b39f331a8e4b0d15b235a4afd ("TXx9: Add 64-bit support")
but was not initialized properly.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-09-05 21:24:12 +01:00
Thomas Bogendoerfer e0cee3eea7 [MIPS] Fix WARNING: at kernel/smp.c:290
trap_init issues flush_icache_range(), which uses ipi functions to
get icache flushing done on all cpus. But this is done before interrupts
are enabled and caused WARN_ON messages. This changeset introduces
a new local_flush_icache_range() and uses it before interrupts (and
additional CPUs) are enabled to avoid this problem.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-09-05 21:24:11 +01:00
Thomas Bogendoerfer 0510617b85 [MIPS] Fix data bus error recovery
With -ffunction-section the entries in __dbe_table aren't no longer
sorted, so the lookup of exception addresses in do_be() failed for
some addresses. To avoid this we now sort __dbe_table.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-09-05 21:24:11 +01:00
David Woodhouse b35de672e7 Revert "[ARM] use the new byteorder headers"
This reverts commit ae82cbfc8b. It
needs the new byteorder headers to be exported to userspace, and
they aren't yet -- and probably shouldn't be, at this point in the
2.6.27 release cycle (or ever, for that matter).

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-05 17:01:50 +01:00
Thomas Gleixner 7cfb043533 HPET: make minimum reprogramming delta useful
The minimum reprogramming delta was hardcoded in HPET ticks,
which is stupid as it does not work with faster running HPETs.
The C1E idle patches made this prominent on AMD/RS690 chipsets,
where the HPET runs with 25MHz. Set it to 5us which seems to be
a reasonable value and fixes the problems on the bug reporters
machines. We have a further sanity check now in the clock events,
which increases the delta when it is not sufficient.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Tested-by: Dmitry Nezhevenko <dion@inhex.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-05 11:11:54 +02:00
Paul Mundt dbce1f649e sh64: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
Follows the SH change.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-05 14:51:28 +09:00
Carmelo Amoroso 323b8c410a sh: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
This patch fixes a problem within the SH implementation of resume_kernel code,
that implements in assembly the bulk of preempt_schedule_irq function without
taking care of the extra code needed to handle the BKL preemptible.

The patch basically consists of removing this asm code and calling the common
C implementation (see kernel/sched.c) as other archs do.

Another change is the missing 'cli' macro invocation at the beginning of
the resume_kernel.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-05 14:42:16 +09:00
Alok N Kataria de014d6176 x86: Change warning message in TSC calibration.
When calibration against PIT fails, the warning that we print is misleading.
In a virtualized environment the VM may get descheduled while calibration
or, the check in PIT calibration may fail due to other virtualization
overheads.

The warning message explicitly assumes that calibration failed due to SMI's
which may not be the case. Change that to something proper.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-03 20:10:37 -07:00
Linus Torvalds 3e25a2d90e Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Fix for getting CPU number in power_save_ppc32_restore()
  powerpc: Fix build error with 64K pages and !hugetlbfs
  powerpc: Work around gcc's -fno-omit-frame-pointer bug
  powerpc: Make sure _etext is after all kernel text
  powerpc: Only make kernel text pages of linear mapping executable
  powerpc: Fix uninitialised variable in VSX alignment code
2008-09-03 17:36:37 -07:00
Chuck Ebbert e6a5652fd1 x86: add io delay quirk for Presario F700
Manually adding "io_delay=0xed" fixes system lockups in ioapic
mode on this machine.

System Information
	Manufacturer: Hewlett-Packard
	Product Name: Presario F700 (KA695EA#ABF)

Base Board Information
	Manufacturer: Quanta
	Product Name: 30D3

Reference:
https://bugzilla.redhat.com/show_bug.cgi?id=459546

Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-09-03 16:42:51 -07:00
Linus Torvalds ec0c15afb4 Split up PIT part of TSC calibration from native_calibrate_tsc
The TSC calibration function is still very complicated, but this makes
it at least a little bit less so by moving the PIT part out into a
helper function of its own.

Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-of-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-03 07:30:13 -07:00
Kumar Gala 7888bc2b47 powerpc: Fix for getting CPU number in power_save_ppc32_restore()
The calculation to get TI_CPU based off of SPRG3 was just plain wrong,
meaning that we were getting garbage for the CPU number on 6xx/G3/G4
based SMP boxes in this code.

Just offset off the stack pointer (to get to thread_info) like all the
other references to TI_CPU do.

This was pointed out by Chen Gong <G.Chen@freescale.com>

[paulus@samba.org - use rlwinm r12,r11,... instead of
 rlwinm r12,r1,...; tophys()]

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:47 +10:00
Benjamin Herrenschmidt 94ee815c05 powerpc: Fix build error with 64K pages and !hugetlbfs
HAVE_ARCH_UNMAPPED_AREA and HAVE_ARCH_UNMAPPED_AREA_TOPDOWN must
be defined whenever CONFIG_PPC_MM_SLICES is enabled, not just when
CONFIG_HUGETLB_PAGE is.  They used to be always defined together but
this is no longer the case since 3a8247cc2c
("powerpc: Only demote individual slices rather than whole process").

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:42 +10:00
Tony Breeds 7563dc6458 powerpc: Work around gcc's -fno-omit-frame-pointer bug
This bug is causing random crashes
(http://bugzilla.kernel.org/show_bug.cgi?id=11414).

-fno-omit-frame-pointer is only needed on powerpc when -pg is also
supplied, and there is a gcc bug that causes incorrect code generation
on 32-bit powerpc when -fno-omit-frame-pointer is used---it uses stack
locations below the stack pointer, which is not allowed by the ABI
because those locations can and sometimes do get corrupted by an
interrupt.

This ensures that CONFIG_FRAME_POINTER is only selected by ftrace.
When CONFIG_FTRACE is enabled we also pass -mno-sched-epilog to work
around the gcc codegen bug.

Patch based on work by:
	Andreas Schwab <schwab@suse.de>
	Segher Boessenkool <segher@kernel.crashing.org>

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:34 +10:00
Stephen Rothwell 303996dace powerpc: Make sure _etext is after all kernel text
This makes core_kernel_text() (and therefore kernel_text_address())
return the correct result.  Currently all the __devinit routines (at
least) will not be considered to be kernel text.

This is just a quick fix for 2.6.27 - hopefully we will be able to fix
this better in 2.6.28.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:26 +10:00
Paul Mackerras 9e88ba4e45 powerpc: Only make kernel text pages of linear mapping executable
Commit bc033b63bb ("powerpc/mm: Fix
attribute confusion with htab_bolt_mapping()") moved the check for
whether we should make pages of the linear mapping executable from
htab_bolt_mapping into its callers, including htab_initialize.
A side-effect of this is that the decision is now made once for
each contiguous section in the LMB array rather than for each page
individually.  This can often mean that the whole of the linear
mapping ends up being executable.

This reverts to the previous behaviour, where individual pages are
checked for being part of the kernel text or not, by moving the check
back down into htab_bolt_mapping.

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:22 +10:00
Michael Neuling 78fbc824ed powerpc: Fix uninitialised variable in VSX alignment code
This fixes an uninitialised variable in the VSX alignment code.  It can
cause warnings from GCC (noticed with gcc-4.1.1).  Gcc is actually
correct in this instance, and this bug could cause the alignment
interrupt handler to send a SIGSEGV to the process on a legitimate
access.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:14 +10:00
Thomas Gleixner fbb16e2438 [x86] Fix TSC calibration issues
Larry Finger reported at http://lkml.org/lkml/2008/9/1/90:
An ancient laptop of mine started throwing errors from b43legacy when
I started using 2.6.27 on it. This has been bisected to commit bfc0f59
"x86: merge tsc calibration".

The unification of the TSC code adopted mostly the 64bit code, which
prefers PMTIMER/HPET over the PIT calibration.

Larrys system has an AMD K6 CPU. Such systems are known to have
PMTIMER incarnations which run at double speed. This results in a
miscalibration of the TSC by factor 0.5. So the resulting calibrated
CPU/TSC speed is half of the real CPU speed, which means that the TSC
based delay loop will run half the time it should run. That might
explain why the b43legacy driver went berserk.

On the other hand we know about systems, where the PIT based
calibration results in random crap due to heavy SMI/SMM
disturbance. On those systems the PMTIMER/HPET based calibration logic
with SMI detection shows better results.

According to Alok also virtualized systems suffer from the PIT
calibration method.

The solution is to use a more wreckage aware aproach than the current
either/or decision.

1) reimplement the retry loop which was dropped from the 32bit code
during the merge. It repeats the calibration and selects the lowest
frequency value as this is probably the closest estimate to the real
frequency

2) Monitor the delta of the TSC values in the delay loop which waits
for the PIT counter to reach zero. If the maximum value is
significantly different from the minimum, then we have a pretty safe
indicator that the loop was disturbed by an SMI.

3) keep the pmtimer/hpet reference as a backup solution for systems
where the SMI disturbance is a permanent point of failure for PIT
based calibration

4) do the loop iteration for both methods, record the lowest value and
decide after all iterations finished.

5) Set a clear preference to PIT based calibration when the result
makes sense.

The implementation does the reference calibration based on
HPET/PMTIMER around the delay, which is necessary for the PIT anyway,
but keeps separate TSC values to ensure the "independency" of the
resulting calibration values.

Tested on various 32bit/64bit machines including Geode 266Mhz, AMD K6
(affected machine with a double speed pmtimer which I grabbed out of
the dump), Pentium class machines and AMD/Intel 64 bit boxen.

Bisected-by:  Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 20:35:56 -07:00
Michael Schmitz 1136cf1106 m68k: atari_keyb_init operator precedence fix
Fix operator precedence bug in atari_keyb_init, which caused a failure on CT60

Signed-off-by: Michael Schmitz <schmitz@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 10:57:52 -07:00
Stephen Rothwell 2ecbf813d5 fix typo in arch/parisc/hpux/fs.c
A parisc allmodconfig build produces this:

arch/parisc/hpux/fs.c:107: error: 'buffer' undeclared (first use in this function)

Introduced by commit da574983de ("[PATCH]
fix hpux_getdents()").

Helge Dille also reported this in bugzilla 11461:

	http://bugzilla.kernel.org/show_bug.cgi?id=11461

and he posted an identical patch.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 10:57:29 -07:00