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/memtype.h>
8#include <asm/apic.h>
9#include <asm/processor.h>
10
11#include "cpu.h"
12
13struct 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 */
26static 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_INTEL_PPIN, CPUID_EBX, 0, 0x00000007, 1 },
30 { X86_FEATURE_RRSBA_CTRL, CPUID_EDX, 2, 0x00000007, 2 },
31 { X86_FEATURE_BHI_CTRL, CPUID_EDX, 4, 0x00000007, 2 },
32 { X86_FEATURE_CQM_LLC, CPUID_EDX, 1, 0x0000000f, 0 },
33 { X86_FEATURE_CQM_OCCUP_LLC, CPUID_EDX, 0, 0x0000000f, 1 },
34 { X86_FEATURE_CQM_MBM_TOTAL, CPUID_EDX, 1, 0x0000000f, 1 },
35 { X86_FEATURE_CQM_MBM_LOCAL, CPUID_EDX, 2, 0x0000000f, 1 },
36 { X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 },
37 { X86_FEATURE_CAT_L2, CPUID_EBX, 2, 0x00000010, 0 },
38 { X86_FEATURE_CDP_L3, CPUID_ECX, 2, 0x00000010, 1 },
39 { X86_FEATURE_CDP_L2, CPUID_ECX, 2, 0x00000010, 2 },
40 { X86_FEATURE_MBA, CPUID_EBX, 3, 0x00000010, 0 },
41 { X86_FEATURE_PER_THREAD_MBA, CPUID_ECX, 0, 0x00000010, 3 },
42 { X86_FEATURE_SGX1, CPUID_EAX, 0, 0x00000012, 0 },
43 { X86_FEATURE_SGX2, CPUID_EAX, 1, 0x00000012, 0 },
44 { X86_FEATURE_SGX_EDECCSSA, CPUID_EAX, 11, 0x00000012, 0 },
45 { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 },
46 { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 },
47 { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 },
48 { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 },
49 { X86_FEATURE_SMBA, CPUID_EBX, 2, 0x80000020, 0 },
50 { X86_FEATURE_BMEC, CPUID_EBX, 3, 0x80000020, 0 },
51 { X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 },
52 { X86_FEATURE_AMD_LBR_V2, CPUID_EAX, 1, 0x80000022, 0 },
53 { X86_FEATURE_AMD_LBR_PMC_FREEZE, CPUID_EAX, 2, 0x80000022, 0 },
54 { 0, 0, 0, 0, 0 }
55};
56
57void init_scattered_cpuid_features(struct cpuinfo_x86 *c)
58{
59 u32 max_level;
60 u32 regs[4];
61 const struct cpuid_bit *cb;
62
63 for (cb = cpuid_bits; cb->feature; cb++) {
64
65 /* Verify that the level is valid */
66 max_level = cpuid_eax(op: cb->level & 0xffff0000);
67 if (max_level < cb->level ||
68 max_level > (cb->level | 0xffff))
69 continue;
70
71 cpuid_count(op: cb->level, count: cb->sub_leaf, eax: &regs[CPUID_EAX],
72 ebx: &regs[CPUID_EBX], ecx: &regs[CPUID_ECX],
73 edx: &regs[CPUID_EDX]);
74
75 if (regs[cb->reg] & (1 << cb->bit))
76 set_cpu_cap(c, cb->feature);
77 }
78}
79

source code of linux/arch/x86/kernel/cpu/scattered.c