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/processor.h>
9
10 #include <asm/apic.h>
11
12 struct cpuid_bit {
13 u16 feature;
14 u8 reg;
15 u8 bit;
16 u32 level;
17 u32 sub_leaf;
18 };
19
20 /* Please keep the leaf sorted by cpuid_bit.level for faster search. */
21 static const struct cpuid_bit cpuid_bits[] = {
22 { X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
23 { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
24 { X86_FEATURE_CQM_LLC, CPUID_EDX, 1, 0x0000000f, 0 },
25 { X86_FEATURE_CQM_OCCUP_LLC, CPUID_EDX, 0, 0x0000000f, 1 },
26 { X86_FEATURE_CQM_MBM_TOTAL, CPUID_EDX, 1, 0x0000000f, 1 },
27 { X86_FEATURE_CQM_MBM_LOCAL, CPUID_EDX, 2, 0x0000000f, 1 },
28 { X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 },
29 { X86_FEATURE_CAT_L2, CPUID_EBX, 2, 0x00000010, 0 },
30 { X86_FEATURE_CDP_L3, CPUID_ECX, 2, 0x00000010, 1 },
31 { X86_FEATURE_MBA, CPUID_EBX, 3, 0x00000010, 0 },
32 { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 },
33 { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 },
34 { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 },
35 { X86_FEATURE_SME, CPUID_EAX, 0, 0x8000001f, 0 },
36 { 0, 0, 0, 0, 0 }
37 };
38
init_scattered_cpuid_features(struct cpuinfo_x86 * c)39 void init_scattered_cpuid_features(struct cpuinfo_x86 *c)
40 {
41 u32 max_level;
42 u32 regs[4];
43 const struct cpuid_bit *cb;
44
45 for (cb = cpuid_bits; cb->feature; cb++) {
46
47 /* Verify that the level is valid */
48 max_level = cpuid_eax(cb->level & 0xffff0000);
49 if (max_level < cb->level ||
50 max_level > (cb->level | 0xffff))
51 continue;
52
53 cpuid_count(cb->level, cb->sub_leaf, ®s[CPUID_EAX],
54 ®s[CPUID_EBX], ®s[CPUID_ECX],
55 ®s[CPUID_EDX]);
56
57 if (regs[cb->reg] & (1 << cb->bit))
58 set_cpu_cap(c, cb->feature);
59 }
60 }
61
get_scattered_cpuid_leaf(unsigned int level,unsigned int sub_leaf,enum cpuid_regs_idx reg)62 u32 get_scattered_cpuid_leaf(unsigned int level, unsigned int sub_leaf,
63 enum cpuid_regs_idx reg)
64 {
65 const struct cpuid_bit *cb;
66 u32 cpuid_val = 0;
67
68 for (cb = cpuid_bits; cb->feature; cb++) {
69
70 if (level > cb->level)
71 continue;
72
73 if (level < cb->level)
74 break;
75
76 if (reg == cb->reg && sub_leaf == cb->sub_leaf) {
77 if (cpu_has(&boot_cpu_data, cb->feature))
78 cpuid_val |= BIT(cb->bit);
79 }
80 }
81
82 return cpuid_val;
83 }
84 EXPORT_SYMBOL_GPL(get_scattered_cpuid_leaf);
85