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| author | Thomas Gleixner <tglx@linutronix.de> | 2024-02-14 21:29:39 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2024-02-15 22:07:36 +0100 |
| commit | 43d86e3cd9a77912772cf7ad37ad94211bf7351d (patch) | |
| tree | 4c8a2061cb829eecf85bd702ca097640793a57d1 /arch | |
| parent | Linux 6.8-rc4 (diff) | |
| download | linux-43d86e3cd9a77912772cf7ad37ad94211bf7351d.tar.xz linux-43d86e3cd9a77912772cf7ad37ad94211bf7351d.zip | |
x86/cpu: Provide cpuid_read() et al.
Provide a few helper functions to read CPUID leafs or individual registers
into a data structure without requiring unions.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/878r3mg570.ffs@tglx
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/cpuid.h | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpuid.h b/arch/x86/include/asm/cpuid.h index 9bee3e7bf973..6b122a31da06 100644 --- a/arch/x86/include/asm/cpuid.h +++ b/arch/x86/include/asm/cpuid.h @@ -127,6 +127,42 @@ static inline unsigned int cpuid_edx(unsigned int op) return edx; } +static inline void __cpuid_read(unsigned int leaf, unsigned int subleaf, u32 *regs) +{ + regs[CPUID_EAX] = leaf; + regs[CPUID_ECX] = subleaf; + __cpuid(regs + CPUID_EAX, regs + CPUID_EBX, regs + CPUID_ECX, regs + CPUID_EDX); +} + +#define cpuid_subleaf(leaf, subleaf, regs) { \ + static_assert(sizeof(*(regs)) == 16); \ + __cpuid_read(leaf, subleaf, (u32 *)(regs)); \ +} + +#define cpuid_leaf(leaf, regs) { \ + static_assert(sizeof(*(regs)) == 16); \ + __cpuid_read(leaf, 0, (u32 *)(regs)); \ +} + +static inline void __cpuid_read_reg(unsigned int leaf, unsigned int subleaf, + enum cpuid_regs_idx regidx, u32 *reg) +{ + u32 regs[4]; + + __cpuid_read(leaf, subleaf, regs); + *reg = regs[regidx]; +} + +#define cpuid_subleaf_reg(leaf, subleaf, regidx, reg) { \ + static_assert(sizeof(*(reg)) == 4); \ + __cpuid_read_reg(leaf, subleaf, regidx, (u32 *)(reg)); \ +} + +#define cpuid_leaf_reg(leaf, regidx, reg) { \ + static_assert(sizeof(*(reg)) == 4); \ + __cpuid_read_reg(leaf, 0, regidx, (u32 *)(reg)); \ +} + static __always_inline bool cpuid_function_is_indexed(u32 function) { switch (function) { |