Commit graph

174 commits

Author SHA1 Message Date
WANG Cong
cf9b111c17 x86: remove pointless comments
Remove old comments that include the old arch/i386 directory.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-19 19:19:54 +02:00
Ingo Molnar
8ce116e599 x86: clean up cpu capabilities accesses, p4-clockmod.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-19 19:19:54 +02:00
Glauber Costa
dd46e3ca73 x86: move apic declarations to mach_apic.h
take them out of the x86_64-specific asm/mach_apic.h

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:30 +02:00
Yinghai Lu
9307cacad0 x86: pat cpu feature bit setting for known cpus
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:20 +02:00
Ingo Molnar
a7c7d0e91d x86: tom2 warning fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:20 +02:00
Yinghai Lu
35605a1027 x86: enable PAT for amd k8 and fam10h
make known_pat_cpu to think amd k8 and fam10h is ok too.

also make tom2 below to be WRBACK

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:20 +02:00
venkatesh.pallipadi@intel.com
2e5d9c857d x86: PAT infrastructure patch
Sets up pat_init() infrastructure.

PAT MSR has following setting.
	PAT
	|PCD
	||PWT
	|||
	000 WB		_PAGE_CACHE_WB
	001 WC		_PAGE_CACHE_WC
	010 UC-		_PAGE_CACHE_UC_MINUS
	011 UC		_PAGE_CACHE_UC

We are effectively changing WT from boot time setting to WC.
UC_MINUS is used to provide backward compatibility to existing /dev/mem
users(X).

reserve_memtype and free_memtype are new interfaces for maintaining alias-free
mapping. It is currently implemented in a simple way with a linked list and
not optimized. reserve and free tracks the effective memory type, as a result
of PAT and MTRR setting rather than what is actually requested in PAT.

pat_init piggy backs on mtrr_init as the rules for setting both pat and mtrr
are same.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:41:19 +02:00
Yinghai Lu
01aaea1afb x86: introduce initial apicid
store initial_apicid from early identify. it is could be different from
phys_proc_id later.

also print it out in /proc/cpuinfo.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:58 +02:00
Yinghai Lu
282bfe21cf x86: show apicid for cpu in proc
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:57 +02:00
Joe Perches
c1db29dbc7 x86: arch/x86/kernel/cpu/feature_names.c - use angle brackets for include
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:57 +02:00
Alexey Dobriyan
11ae9dd481 x86: switch to proc_create()
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Ingo Molnar
10cd5a1e54 x86: clean up cpu capabilities accesses, transmeta.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Ingo Molnar
d0e95ebdc5 x86: clean up cpu capabilities in arch/x86/kernel/cpu/intel.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Ingo Molnar
1d007cd5ae x86: clean up cpu capabilities accesses, cyrix.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Ingo Molnar
4cbe668add x86: clean up cpu capabilities accesses, common.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Ingo Molnar
e1a94a974c x86: clean up cpu capabilities accesses, centaur.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Ingo Molnar
16282a8e25 x86: clean up cpu capabilities accesses, amd.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Ingo Molnar
9716951efd x86: clean up cpu capabilities accesses, generic
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
34048c9e92 x86: coding style fixes to arch/x86/kernel/cpu/common.c
Before:
   total: 55 errors, 6 warnings, 727 lines checked
After:
   total: 0 errors, 3 warnings, 734 lines checked

No code changed:

arch/x86/kernel/cpu/common.o:

   text	   data	    bss	    dec	    hex	filename
   3500	   4611	     44	   8155	   1fdb	common.o.before
   3500	   4611	     44	   8155	   1fdb	common.o.after

md5:
   e37091f11fbeb682c0db152ac3022a38  common.o.before.asm
   e37091f11fbeb682c0db152ac3022a38  common.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
adf85265b4 x86: coding style fixes to arch/x86/kernel/cpu/cyrix.c
Before:
   total: 46 errors, 10 warnings, 450 lines checked
After:
   total: 1 errors, 10 warnings, 449 lines checked

No code changed:

arch/x86/kernel/cpu/cyrix.o:

   text	   data	    bss	    dec	    hex	filename
   2048	    908	      4	   2960	    b90	cyrix.o.before
   2048	    908	      4	   2960	    b90	cyrix.o.after

md5:
   9add5e69dbd788f91ff24eea8462dad7  cyrix.o.before.asm
   9add5e69dbd788f91ff24eea8462dad7  cyrix.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
d677759e99 x86: coding style fixes to arch/x86/kernel/cpu/mcheck/mce_32.c
Before:
   total: 10 errors, 3 warnings, 90 lines checked
After:
   total: 0 errors, 3 warnings, 90 lines checked

No code changed:

arch/x86/kernel/cpu/mcheck/mce_32.o:

   text	   data	    bss	    dec	    hex	filename
    287	     42	     12	    341	    155	mce_32.o.before
    287	     42	     12	    341	    155	mce_32.o.after

md5:
   fede5ff8e6bc3f62e8e691ca6c45eb39  mce_32.o.before.asm
   fede5ff8e6bc3f62e8e691ca6c45eb39  mce_32.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
4de816297d x86: coding style fixes to arch/x86/kernel/cpu/mcheck/winchip.c
Before:
   total: 4 errors, 0 warnings, 36 lines checked
After:
   total: 0 errors, 0 warnings, 36 lines checked

No code changed:

arch/x86/kernel/cpu/mcheck/winchip.o:

   text	   data	    bss	    dec	    hex	filename
    222	      0	      4	    226	     e2	winchip.o.before
    222	      0	      4	    226	     e2	winchip.o.after

md5:
   9caefa12256c5f7d71ef324f6d01a2d5  winchip.o.before.asm
   9caefa12256c5f7d71ef324f6d01a2d5  winchip.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
714a9ac2ef x86: coding style fixes to arch/x86/kernel/cpu/mcheck/non-fatal.c
Before:
   total: 5 errors, 5 warnings, 91 lines checked
After:
   total: 0 errors, 0 warnings, 94 lines checked

No code changed:

arch/x86/kernel/cpu/mcheck/non-fatal.o:

   text	   data	    bss	    dec	    hex	filename
    441	     80	      4	    525	    20d	non-fatal.o.before
    441	     80	      4	    525	    20d	non-fatal.o.after

md5:
   137bc114d2020ad331d5e76444a2c7d3  non-fatal.o.before.asm
   137bc114d2020ad331d5e76444a2c7d3  non-fatal.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
fb87a298fb x86: coding style fixes to arch/x86/kernel/cpu/amd.c
Before:
   total: 42 errors, 26 warnings, 350 lines checked
After:
   total: 0 errors, 26 warnings, 352 lines checked

No code changed:

arch/x86/kernel/cpu/amd.o:

   text	   data	    bss	    dec	    hex	filename
   1936	    328	      0	   2264	    8d8	amd.o.before
   1936	    328	      0	   2264	    8d8	amd.o.after

md5:
   873430a88faaf31bb4bbfe3a2a691e45  amd.o.before.asm
   873430a88faaf31bb4bbfe3a2a691e45  amd.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
f975182719 x86: coding style fixes to arch/x86/kernel/cpu/transmeta.c
Before:
   total: 13 errors, 3 warnings, 105 lines checked
After:
   total: 0 errors, 3 warnings, 107 lines checked

No code changed:

arch/x86/kernel/cpu/transmeta.o:

   text	   data	    bss	    dec	    hex	filename
    713	    324	      0	   1037	    40d	transmeta.o.before
    713	    324	      0	   1037	    40d	transmeta.o.after

md5:
   19abe2cafac617e1e2aadc4aa4e9923b  transmeta.o.before.asm
   19abe2cafac617e1e2aadc4aa4e9923b  transmeta.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:50 +02:00
Paolo Ciarrocchi
e0f0257044 x86: coding style fixes to arch/x86/kernel/cpu/mtrr/state.c
Before:
   total: 6 errors, 5 warnings, 80 lines checked
After:
   total: 0 errors, 4 warnings, 82 lines checked

No code changed:

arch/x86/kernel/cpu/mtrr/state.o:

   text	   data	    bss	    dec	    hex	filename
    313	      0	      4	    317	    13d	state.o.before
    313	      0	      4	    317	    13d	state.o.after

md5:
   a0fbd61096205f9180f0bf45ed386d61  state.o.before.asm
   a0fbd61096205f9180f0bf45ed386d61  state.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:49 +02:00
Paolo Ciarrocchi
65eb6b4326 x86: coding style fixes to arch/x86/kernel/cpu/intel.c
Before:
   total: 37 errors, 16 warnings, 366 lines checked
After:
   total: 0 errors, 15 warnings, 369 lines checked

No code changed:

arch/x86/kernel/cpu/intel.o:

   text	   data	    bss	    dec	    hex	filename
   1534	    452	      0	   1986	    7c2	intel.o.before
   1534	    452	      0	   1986	    7c2	intel.o.after

md5:
   1ca348a06de6eb354c4b6ea715a57db5  intel.o.before.asm
   1ca348a06de6eb354c4b6ea715a57db5  intel.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:49 +02:00
Paolo Ciarrocchi
48e6b7a050 x86: coding style fixes to arch/x86/kernel/cpu/umc.c
Before:
   total: 3 errors, 1 warnings, 23 lines checked
After:
   total: 0 errors, 0 warnings, 25 lines checked

No code changed:

arch/x86/kernel/cpu/umc.o:

   text	   data	    bss	    dec	    hex	filename
     24	    616	      0	    640	    280	umc.o.before
     24	    616	      0	    640	    280	umc.o.after

md5:
   e8daa3eaed0963a0cdd2e83c2e1f9823  umc.o.before.asm
   e8daa3eaed0963a0cdd2e83c2e1f9823  umc.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:49 +02:00
Paolo Ciarrocchi
2c5847837f x86: coding style fixes to arch/x86/kernel/cpu/mcheck/p6.c
Before:
   total: 16 errors, 13 warnings, 122 lines checked
After:
   total: 0 errors, 0 warnings, 122 lines checked

No code changed:

arch/x86/kernel/cpu/mcheck/p6.o:

   text	   data	    bss	    dec	    hex	filename
   1082	      0	      8	   1090	    442	p6.o.before
   1082	      0	      8	   1090	    442	p6.o.after

md5:
   4e283fbc1b68240f1724d9725007d379  p6.o.before.asm
   4e283fbc1b68240f1724d9725007d379  p6.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:49 +02:00
Hiroshi Shimamoto
eb19067d16 x86: unify cpu/proc|_64.c
Now cpu/proc.c and cpu/proc_64.c are same.
So cpu/proc_64.c can be removed.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Hiroshi Shimamoto
2aef77204e x86: cosmetic unification cpu/proc|_64.c
make cpu/proc.c and cpu/proc_64.c same.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Hiroshi Shimamoto
f84c3a429f x86: add power management line in /proc/cpuinfo
Change /proc/cpuinfo on 32-bit, it will look like on 64-bit.
'power management' line is added and power management information
will be printed at the line.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Hiroshi Shimamoto
a967ceac01 x86: make cpu/proc|_64.c similar
clean up for unification.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Hiroshi Shimamoto
8fa6878ffc x86: split cpuinfo from setup_64.c into cpu/proc_64.c
x86 /proc/cpuinfo code can be unified.
This is the first step of unification.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Paolo Ciarrocchi
c99aa3804e x86: coding style fixes to arch/x86/kernel/cpu/nexgen.c
arch/x86/kernel/cpu/nexgen.o:
   text    data     bss     dec     hex filename
    111     316       0     427     1ab nexgen.o.before
    111     316       0     427     1ab nexgen.o.after
md5:
 e796efefea9ebc6644338bad226599ee  nexgen.o.before.asm
 e796efefea9ebc6644338bad226599ee  nexgen.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Paolo Ciarrocchi
1577720524 x86: coding style fixes to arch/x86/kernel/cpu/mcheck/p5.c
The patch make the file errors free.
Only 4 "WARNING: line over 80 characters" left.

arch/x86/kernel/cpu/mcheck/p5.o:
   text    data     bss     dec     hex filename
    452       0       4     456     1c8 p5.o.before
    452       0       4     456     1c8 p5.o.after
md5:
50c945ef150aa95bf0481cc3e1dc3315  p5.o.before.asm
50c945ef150aa95bf0481cc3e1dc3315  p5.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:48 +02:00
Ingo Molnar
edc05e6de3 x86: more coding style fixes in centaur.c
no code changed:

 arch/x86/kernel/cpu/centaur.o:
    text    data     bss     dec     hex filename
    1031     324       0    1355     54b centaur.o.before
    1031     324       0    1355     54b centaur.o.after

 md5:
  4f306a7f980b58eb69c4bdcfcde565f1  centaur.o.before.asm
  4f306a7f980b58eb69c4bdcfcde565f1  centaur.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 17:40:47 +02:00
Paolo Ciarrocchi
29a9994bd8 x86: coding style fixes for arch/x86/kernel/cpu/centaur.c
Kills more than 150 errors/warnings

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 17:40:47 +02:00
Thomas Petazzoni
03ae5768b6 x86: use ELF section to list CPU vendor specific code
Replace the hardcoded list of initialization functions for each CPU
vendor by a list in an ELF section, which is read at initialization in
arch/x86/kernel/cpu/cpu.c to fill the cpu_devs[] array. The ELF
section, named .x86cpuvendor.init, is reclaimed after boot, and
contains entries of type "struct cpu_vendor_dev" which associates a
vendor number with a pointer to a "struct cpu_dev" structure.

This first modification allows to remove all the VENDOR_init_cpu()
functions.

This patch also removes the hardcoded calls to early_init_amd() and
early_init_intel(). Instead, we add a "c_early_init" member to the
cpu_dev structure, which is then called if not NULL by the generic CPU
initialization code. Unfortunately, in early_cpu_detect(), this_cpu is
not yet set, so we have to use the cpu_devs[] array directly.

This patch is part of the Linux Tiny project, and is needed for
further patch that will allow to disable compilation of unused CPU
support code.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 17:40:47 +02:00
Rusty Russell
64ba4f230d Fix booting pentium+ with dodgy TSC
We handle a broken tsc these days, so no need to panic.  We clear the
TSC bit when tsc_init decides it's unreliable (eg.  under lguest w/ bad
host TSC), leading to bogus panic.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-06 16:10:40 -07:00
Ingo Molnar
9c9b81f773 x86: print message if nmi_watchdog=2 cannot be enabled
right now if there's no CPU support for nmi_watchdog=2 we'll just
refuse it silently.

print a useful warning.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-04 18:36:45 +02:00
Ingo Molnar
4f14bdef41 x86: fix nmi_watchdog=2 on Pentium-D CPUs
implement nmi_watchdog=2 on this class of CPUs:

  cpu family      : 15
  model           : 6
  model name      : Intel(R) Pentium(R) D CPU 3.00GHz

the watchdog's ->setup() method is safe anyway, so if the CPU
cannot support it we'll bail out safely.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-04 18:36:45 +02:00
Stephan Diestelhorst
c6e8256a7b x86, cpufreq: fix Speedfreq-SMI call that clobbers ECX
I have found that using SMI to change the cpu's frequency on my DELL
Latitude L400 clobbers the ECX register in speedstep_set_state, causing
unneccessary retries because the "state" variable has changed silently (GCC
assumes it is still present in ECX).

play safe and avoid gcc caching any register across IO port accesses
that trigger SMIs.

Signed-off by: <Stephan.Diestelhorst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-26 22:23:40 +01:00
Randy Dunlap
1d3381ebf4 x86: convert mtrr/generic.c to kernel-doc
Convert function comment blocks to kernel-doc notation.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-03-26 22:23:40 +01:00
Yinghai Lu
5dca6a1bb0 x86: trim mtrr don't close gap for resource allocation.
fix the bug reported here:

	http://bugzilla.kernel.org/show_bug.cgi?id=10232

use update_memory_range() instead of add_memory_range() directly
to avoid closing the gap.

( the new code only affects and runs on systems where the MTRR
  workaround triggers. )

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-03-21 17:06:15 +01:00
Dave Jones
0e5aa8d621 [CPUFREQ] Remove debugging message from e_powersaver
We don't need to printk a message every time we transition.
Leave the code there, but ifdef'd out, as it's useful when
adding support for new processors.

Reported-by: Petr Titěra <P.Titera@century.cz>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-03-05 14:45:31 -05:00
Mikael Pettersson
12c247a671 x86: fix boot failure on 486 due to TSC breakage
> Diffing dmesg between git7 and git8 doesn't sched any light since
 > git8 also removed the printouts of the x86 caps as they were being
 > initialised and updated. I'm currently adding those printouts back
 > in the hope of seeing where and when the caps get broken.

That turned out to be very illuminating:

 --- dmesg-2.6.24-git7	2008-02-24 18:01:25.295851000 +0100
 +++ dmesg-2.6.24-git8	2008-02-24 18:01:25.530358000 +0100
 ...
 CPU: After generic identify, caps: 00000003 00000000 00000000 00000000 00000000 00000000 00000000 00000000

 CPU: After all inits, caps: 00000003 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+CPU: After applying cleared_cpu_caps, caps: 00000013 00000000 00000000 00000000 00000000 00000000 00000000 00000000

Notice how the TSC cap bit goes from Off to On.

(The first two lines are printout loops from -git7 forward-ported
to -git8, the third line is the same printout loop added just after
the xor-with-cleared_cpu_caps[] loop.)

Here's how the breakage occurs:
1. arch/x86/kernel/tsc_32.c:tsc_init() sees !cpu_has_tsc,
   so bails and calls setup_clear_cpu_cap(X86_FEATURE_TSC).
2. include/asm-x86/cpufeature.h:setup_clear_cpu_cap(bit) clears
   the bit in boot_cpu_data and sets it in cleared_cpu_caps
3. arch/x86/kernel/cpu/common.c:identify_cpu() XORs all caps
   in with cleared_cpu_caps
   HOWEVER, at this point c->x86_capability correctly has TSC
   Off, cleared_cpu_caps has TSC On, so the XOR incorrectly
   sets TSC to On in c->x86_capability, with disastrous results.

The real bug is that clearing bits with XOR only works if the
bits are known to be 1 prior to the XOR, and that's not true here.

A simple fix is to convert the XOR to AND-NOT instead. The following
patch does that, and allows my 486 to boot 2.6.25-rc kernels again.

[ mingo@elte.hu: fixed a similar bug in setup_64.c as well. ]

The breakage was introduced via commit 7d851c8d3d.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-26 12:56:04 +01:00
Joerg Roedel
4147c8747e x86: don't print a warning when MTRR are blank and running in KVM
Inside a KVM virtual machine the MTRRs are usually blank. This confuses Linux
and causes a warning message at boot. This patch removes that warning message
when running Linux as a KVM guest.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-26 12:55:57 +01:00
Randy Dunlap
f5106d91f2 x86/mtrr: fix kernel-doc missing notation
Fix mtrr kernel-doc warning:
Warning(linux-2.6.24-git12//arch/x86/kernel/cpu/mtrr/main.c:677): No description found for parameter 'end_pfn'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-26 12:55:52 +01:00
H. Peter Anvin
a7ef94e688 x86: do not promote TM3x00/TM5x00 to i686-class
We have been promoting Transmeta TM3x00/TM5x00 chips to i686-class
based on the notion that they contain all the user-space visible
features of an i686-class chip.  However, this is not actually true:
they lack the EA-taking long NOPs (0F 1F /0).  Since this is a
userspace-visible incompatibility, downgrade these CPUs to the
manufacturer-defined i586 level.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-26 12:55:50 +01:00