Release 4.9 arch/x86/kernel/cpu/scattered.c
/*
* Routines to identify additional cpu features that are scattered in
* cpuid space.
*/
#include <linux/cpu.h>
#include <asm/pat.h>
#include <asm/processor.h>
#include <asm/apic.h>
struct cpuid_bit {
u16 feature;
u8 reg;
u8 bit;
u32 level;
u32 sub_leaf;
};
enum cpuid_regs {
CR_EAX = 0,
CR_ECX,
CR_EDX,
CR_EBX
};
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, CR_EBX,25, 0x00000007, 0 },
{ X86_FEATURE_AVX512_4VNNIW, CR_EDX, 2, 0x00000007, 0 },
{ X86_FEATURE_AVX512_4FMAPS, CR_EDX, 3, 0x00000007, 0 },
{ X86_FEATURE_APERFMPERF, CR_ECX, 0, 0x00000006, 0 },
{ X86_FEATURE_EPB, CR_ECX, 3, 0x00000006, 0 },
{ X86_FEATURE_HW_PSTATE, CR_EDX, 7, 0x80000007, 0 },
{ X86_FEATURE_CPB, CR_EDX, 9, 0x80000007, 0 },
{ X86_FEATURE_PROC_FEEDBACK, CR_EDX,11, 0x80000007, 0 },
{ 0, 0, 0, 0, 0 }
};
for (cb = cpuid_bits; cb->feature; cb++) {
/* Verify that the level is valid */
max_level = cpuid_eax(cb->level & 0xffff0000);
if (max_level < cb->level ||
max_level > (cb->level | 0xffff))
continue;
cpuid_count(cb->level, cb->sub_leaf, ®s[CR_EAX],
®s[CR_EBX], ®s[CR_ECX], ®s[CR_EDX]);
if (regs[cb->reg] & (1 << cb->bit))
set_cpu_cap(c, cb->feature);
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| h. peter anvin | h. peter anvin | 189 | 75.90% | 1 | 20.00% |
| piotr luc | piotr luc | 24 | 9.64% | 1 | 20.00% |
| jacob shin | jacob shin | 14 | 5.62% | 1 | 20.00% |
| alexander shishkin | alexander shishkin | 12 | 4.82% | 1 | 20.00% |
| thomas renninger | thomas renninger | 10 | 4.02% | 1 | 20.00% |
| Total | 249 | 100.00% | 5 | 100.00% |
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| h. peter anvin | h. peter anvin | 235 | 79.39% | 1 | 16.67% |
| piotr luc | piotr luc | 24 | 8.11% | 1 | 16.67% |
| jacob shin | jacob shin | 14 | 4.73% | 1 | 16.67% |
| alexander shishkin | alexander shishkin | 12 | 4.05% | 1 | 16.67% |
| thomas renninger | thomas renninger | 10 | 3.38% | 1 | 16.67% |
| maxime jayat | maxime jayat | 1 | 0.34% | 1 | 16.67% |
| Total | 296 | 100.00% | 6 | 100.00% |