diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 8f6ac5be84b7c3900ceb4db396f49ffa09140ab4..e7f8c62701d4af54315238c99b533dd68dacf650 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -189,6 +189,9 @@ extern void identify_secondary_cpu(struct cpuinfo_x86 *); extern void print_cpu_info(struct cpuinfo_x86 *); void print_cpu_msr(struct cpuinfo_x86 *); extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c); +extern u32 get_scattered_cpuid_leaf(unsigned int level, + unsigned int sub_leaf, + enum cpuid_regs_idx reg); extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c); extern void init_amd_cacheinfo(struct cpuinfo_x86 *c); diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index dbb470e839f88ad96d481b30998dca63db41b54c..d1316f9c8329846b0d3f7dede754fa0eef256bd3 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -17,24 +17,25 @@ struct cpuid_bit { u32 sub_leaf; }; +/* Please keep the leaf sorted by cpuid_bit.level for faster search. */ +static const struct cpuid_bit cpuid_bits[] = { + { X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 }, + { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 }, + { X86_FEATURE_INTEL_PT, CPUID_EBX, 25, 0x00000007, 0 }, + { X86_FEATURE_AVX512_4VNNIW, CPUID_EDX, 2, 0x00000007, 0 }, + { X86_FEATURE_AVX512_4FMAPS, CPUID_EDX, 3, 0x00000007, 0 }, + { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 }, + { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, + { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 }, + { 0, 0, 0, 0, 0 } +}; + void init_scattered_cpuid_features(struct cpuinfo_x86 *c) { u32 max_level; u32 regs[4]; const struct cpuid_bit *cb; - static const struct cpuid_bit cpuid_bits[] = { - { X86_FEATURE_INTEL_PT, CPUID_EBX, 25, 0x00000007, 0 }, - { X86_FEATURE_AVX512_4VNNIW, CPUID_EDX, 2, 0x00000007, 0 }, - { X86_FEATURE_AVX512_4FMAPS, CPUID_EDX, 3, 0x00000007, 0 }, - { X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 }, - { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 }, - { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 }, - { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, - { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 }, - { 0, 0, 0, 0, 0 } - }; - for (cb = cpuid_bits; cb->feature; cb++) { /* Verify that the level is valid */ @@ -51,3 +52,27 @@ void init_scattered_cpuid_features(struct cpuinfo_x86 *c) set_cpu_cap(c, cb->feature); } } + +u32 get_scattered_cpuid_leaf(unsigned int level, unsigned int sub_leaf, + enum cpuid_regs_idx reg) +{ + const struct cpuid_bit *cb; + u32 cpuid_val = 0; + + for (cb = cpuid_bits; cb->feature; cb++) { + + if (level > cb->level) + continue; + + if (level < cb->level) + break; + + if (reg == cb->reg && sub_leaf == cb->sub_leaf) { + if (cpu_has(&boot_cpu_data, cb->feature)) + cpuid_val |= BIT(cb->bit); + } + } + + return cpuid_val; +} +EXPORT_SYMBOL_GPL(get_scattered_cpuid_leaf);