From 506ed6b53e00ba303ad778122f08e1fca7cf5efb Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 12 Oct 2011 17:46:33 -0700 Subject: [PATCH] x86, intel: Output microcode revision in /proc/cpuinfo 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 Acked-by: H. Peter Anvin Link: http://lkml.kernel.org/r/1318466795-7393-1-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 4 +++- arch/x86/kernel/cpu/intel.c | 9 +++++++++ arch/x86/kernel/cpu/mcheck/mce.c | 9 +++++++-- arch/x86/kernel/cpu/proc.c | 2 ++ arch/x86/kernel/microcode_intel.c | 14 +++++--------- 5 files changed, 26 insertions(+), 12 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 0d1171c..b650435 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -111,6 +111,7 @@ struct cpuinfo_x86 { /* Index into per_cpu list: */ u16 cpu_index; #endif + u32 microcode; } __attribute__((__aligned__(SMP_CACHE_BYTES))); #define X86_VENDOR_INTEL 0 @@ -179,7 +180,8 @@ static inline void native_cpuid(unsigned int *eax, unsigned int *ebx, "=b" (*ebx), "=c" (*ecx), "=d" (*edx) - : "0" (*eax), "2" (*ecx)); + : "0" (*eax), "2" (*ecx) + : "memory"); } static inline void load_cr3(pgd_t *pgdir) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index ed6086e..26627a3 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -47,6 +47,15 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) (c->x86 == 0x6 && c->x86_model >= 0x0e)) set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); + if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64)) { + unsigned lower_word; + + wrmsr(MSR_IA32_UCODE_REV, 0, 0); + /* Required by the SDM */ + sync_core(); + rdmsr(MSR_IA32_UCODE_REV, lower_word, c->microcode); + } + /* * Atom erratum AAE44/AAF40/AAG38/AAH41: * diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 08363b0..8af6fa4 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -217,8 +217,13 @@ static void print_mce(struct mce *m) pr_cont("MISC %llx ", m->misc); pr_cont("\n"); - pr_emerg(HW_ERR "PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x\n", - m->cpuvendor, m->cpuid, m->time, m->socketid, m->apicid); + /* + * Note this output is parsed by external tools and old fields + * should not be changed. + */ + pr_emerg(HW_ERR "PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x microcode %u\n", + m->cpuvendor, m->cpuid, m->time, m->socketid, m->apicid, + cpu_data(m->extcpu).microcode); /* * Print out human-readable details about the MCE error, diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c index 62ac8cb..6254fda 100644 --- a/arch/x86/kernel/cpu/proc.c +++ b/arch/x86/kernel/cpu/proc.c @@ -85,6 +85,8 @@ static int show_cpuinfo(struct seq_file *m, void *v) seq_printf(m, "stepping\t: %d\n", c->x86_mask); else seq_printf(m, "stepping\t: unknown\n"); + if (c->microcode) + seq_printf(m, "microcode\t: %u\n", c->microcode); if (cpu_has(c, X86_FEATURE_TSC)) { unsigned int freq = cpufreq_quick_get(cpu); diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c index 1a1b606..3ca42d0 100644 --- a/arch/x86/kernel/microcode_intel.c +++ b/arch/x86/kernel/microcode_intel.c @@ -161,12 +161,7 @@ static int collect_cpu_info(int cpu_num, struct cpu_signature *csig) csig->pf = 1 << ((val[1] >> 18) & 7); } - wrmsr(MSR_IA32_UCODE_REV, 0, 0); - /* see notes above for revision 1.07. Apparent chip bug */ - sync_core(); - /* get the current revision from MSR 0x8B */ - rdmsr(MSR_IA32_UCODE_REV, val[0], csig->rev); - + csig->rev = c->microcode; pr_info("CPU%d sig=0x%x, pf=0x%x, revision=0x%x\n", cpu_num, csig->sig, csig->pf, csig->rev); @@ -299,9 +294,9 @@ static int apply_microcode(int cpu) struct microcode_intel *mc_intel; struct ucode_cpu_info *uci; unsigned int val[2]; - int cpu_num; + int cpu_num = raw_smp_processor_id(); + struct cpuinfo_x86 *c = &cpu_data(cpu_num); - cpu_num = raw_smp_processor_id(); uci = ucode_cpu_info + cpu; mc_intel = uci->mc; @@ -317,7 +312,7 @@ static int apply_microcode(int cpu) (unsigned long) mc_intel->bits >> 16 >> 16); wrmsr(MSR_IA32_UCODE_REV, 0, 0); - /* see notes above for revision 1.07. Apparent chip bug */ + /* As documented in the SDM: Do a CPUID 1 here */ sync_core(); /* get the current revision from MSR 0x8B */ @@ -335,6 +330,7 @@ static int apply_microcode(int cpu) (mc_intel->hdr.date >> 16) & 0xff); uci->cpu_sig.rev = val[1]; + c->microcode = val[1]; return 0; } -- 2.7.4