xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/microcode/intel: Add a helper which gives the microcode revision

Browse Source 
Since on Intel we're required to do CPUID(1) first, before reading
the microcode revision MSR, let's add a special helper which does the
required steps so that we don't forget to do them next time, when we
want to read the microcode revision.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20170109114147.5082-4-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Borislav Petkov
2017-01-09 12:41:45 +01:00
committed by Thomas Gleixner
parent f3e2a51f56
commit 4167709bbf
3 changed files with 31 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
arch/x86/include/asm/microcode_intel.h
View File

@@ -52,6 +52,21 @@ struct extended_sigtable {
#define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
static inline u32 intel_get_microcode_revision(void)
{
u32 rev, dummy;
native_wrmsrl(MSR_IA32_UCODE_REV, 0);
/* As documented in the SDM: Do a CPUID 1 here */
native_cpuid_eax(1);
/* get the current revision from MSR 0x8B */
native_rdmsr(MSR_IA32_UCODE_REV, dummy, rev);
return rev;
}
#ifdef CONFIG_MICROCODE_INTEL
extern void __init load_ucode_intel_bsp(void);
extern void load_ucode_intel_ap(void);