1 /* 2 * Routines to identify additional cpu features that are scattered in 3 * cpuid space. 4 */ 5 #include <linux/cpu.h> 6 7 #include <asm/pat.h> 8 #include <asm/apic.h> 9 #include <asm/processor.h> 10 11 #include "cpu.h" 12 13 struct cpuid_bit { 14 u16 feature; 15 u8 reg; 16 u8 bit; 17 u32 level; 18 u32 sub_leaf; 19 }; 20 21 /* 22 * Please keep the leaf sorted by cpuid_bit.level for faster search. 23 * X86_FEATURE_MBA is supported by both Intel and AMD. But the CPUID 24 * levels are different and there is a separate entry for each. 25 */ 26 static const struct cpuid_bit cpuid_bits[] = { 27 { X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 }, 28 { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 }, 29 { X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 }, 30 { X86_FEATURE_CAT_L2, CPUID_EBX, 2, 0x00000010, 0 }, 31 { X86_FEATURE_CDP_L3, CPUID_ECX, 2, 0x00000010, 1 }, 32 { X86_FEATURE_CDP_L2, CPUID_ECX, 2, 0x00000010, 2 }, 33 { X86_FEATURE_MBA, CPUID_EBX, 3, 0x00000010, 0 }, 34 { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 }, 35 { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, 36 { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 }, 37 { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 }, 38 { X86_FEATURE_SME, CPUID_EAX, 0, 0x8000001f, 0 }, 39 { X86_FEATURE_SEV, CPUID_EAX, 1, 0x8000001f, 0 }, 40 { 0, 0, 0, 0, 0 } 41 }; 42 43 void init_scattered_cpuid_features(struct cpuinfo_x86 *c) 44 { 45 u32 max_level; 46 u32 regs[4]; 47 const struct cpuid_bit *cb; 48 49 for (cb = cpuid_bits; cb->feature; cb++) { 50 51 /* Verify that the level is valid */ 52 max_level = cpuid_eax(cb->level & 0xffff0000); 53 if (max_level < cb->level || 54 max_level > (cb->level | 0xffff)) 55 continue; 56 57 cpuid_count(cb->level, cb->sub_leaf, ®s[CPUID_EAX], 58 ®s[CPUID_EBX], ®s[CPUID_ECX], 59 ®s[CPUID_EDX]); 60 61 if (regs[cb->reg] & (1 << cb->bit)) 62 set_cpu_cap(c, cb->feature); 63 } 64 } 65