Reimplement FPU detection code in C and drop old, not-so-recommended
detection method in asm. Move all the relevant stuff into i387.c where
it conceptually belongs. Finally drop cpuinfo_x86.hard_math.

[ hpa: huge thanks to Borislav for taking my original concept patch
  and productizing it ]

[ Boris, note to self: do not use static_cpu_has before alternatives! ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1367244262-29511-2-git-send-email-bp@alien8.de
Link: http://lkml.kernel.org/r/1365436666-9837-2-git-send-email-bp@alien8.de
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

... to the new facility.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-5-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

... to the new facility. Add a reference to the wikipedia article
explaining the FDIV test we're doing here.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

... to using the new facility and drop the cpuinfo_x86 member.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-3-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Remove 32-bit x86 a cmdline param "no-hlt",
and the cpuinfo_x86.hlt_works_ok that it sets.

If a user wants to avoid HLT, then "idle=poll"
is much more useful, as it avoids invocation of HLT
in idle, while "no-hlt" failed to do so.

Indeed, hlt_works_ok was consulted in only 3 places.

First, in /proc/cpuinfo where "hlt_bug yes"
would be printed if and only if the user booted
the system with "no-hlt" -- as there was no other code
to set that flag.

Second, check_hlt() would not invoke halt() if "no-hlt"
were on the cmdline.

Third, it was consulted in stop_this_cpu(), which is invoked
by native_machine_halt()/reboot_interrupt()/smp_stop_nmi_callback() --
all cases where the machine is being shutdown/reset.
The flag was not consulted in the more frequently invoked
play_dead()/hlt_play_dead() used in processor offline and suspend.

Since Linux-3.0 there has been a run-time notice upon "no-hlt" invocations
indicating that it would be removed in 2012.

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org

Remove support for FPU error reporting via IRQ 13, as opposed to
exception 16 (#MF).  One last remnant of i386 gone.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Alan Cox <alan@linux.intel.com>

Since 'cpu == -1' in cpumask_next() is legal, no need to handle
'*pos == 0' specially.

About the comments:

	/* just in case, cpu 0 is not the first */

A test with a cpumask in which cpu 0 is not the first has been
done, and it works well.

This patch will remove that useless branch to clean the code.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: kjwinchester@gmail.com
Cc: borislav.petkov@amd.com
Cc: ak@linux.intel.com
Link: http://lkml.kernel.org/r/1348033343-23658-1-git-send-email-wangyun@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Several fields in struct cpuinfo_x86 were not defined for the
!SMP case, likely to save space.  However, those fields still
have some meaning for UP, and keeping them allows some #ifdef
removal from other files.  The additional size of the UP kernel
from this change is not significant enough to worry about
keeping up the distinction:

	   text    data     bss     dec     hex filename
	4737168	 506459	 972040	6215667	 5ed7f3	vmlinux.o.before
	4737444	 506459	 972040	6215943	 5ed907	vmlinux.o.after

for a difference of 276 bytes for an example UP config.

If someone wants those 276 bytes back badly then it should
be implemented in a cleaner way.

Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Cc: Steffen Persvold <sp@numascale.com>
Link: http://lkml.kernel.org/r/1324428742-12498-1-git-send-email-kjwinchester@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

506ed6b53e00 ("x86, intel: Output microcode revision in /proc/cpuinfo")
added microcode revision format to /proc/cpuinfo and the MCE handler in
decimal format but both AMD and Intel patch levels are handled as hex
numbers. Fix it.

Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

I got a request to make it easier to determine the microcode
update level on Intel CPUs. This patch adds a new "microcode"
field to /proc/cpuinfo.

The microcode level is also outputed on fatal machine checks
together with the other CPUID model information.

I removed the respective code from the microcode update driver,
it just reads the field from cpu_data. Also when the microcode
is updated it fills in the new values too.

I had to add a memory barrier to native_cpuid to prevent it
being optimized away when the result is not used.

This turns out to clean up further code which already got this
information manually. This is done in followon patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1318466795-7393-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>