diff options
Diffstat (limited to 'MdePkg/Library/BaseLib/Ia32/CpuId.c')
| -rw-r--r-- | MdePkg/Library/BaseLib/Ia32/CpuId.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/CpuId.c b/MdePkg/Library/BaseLib/Ia32/CpuId.c index 73f12bcaee..6fbc5375bc 100644 --- a/MdePkg/Library/BaseLib/Ia32/CpuId.c +++ b/MdePkg/Library/BaseLib/Ia32/CpuId.c @@ -17,6 +17,31 @@ //
+/**
+ Retrieves CPUID information.
+
+ Executes the CPUID instruction with EAX set to the value specified by Index.
+ This function always returns Index.
+ If Eax is not NULL, then the value of EAX after CPUID is returned in Eax.
+ If Ebx is not NULL, then the value of EBX after CPUID is returned in Ebx.
+ If Ecx is not NULL, then the value of ECX after CPUID is returned in Ecx.
+ If Edx is not NULL, then the value of EDX after CPUID is returned in Edx.
+ This function is only available on IA-32 and X64.
+
+ @param Index The 32-bit value to load into EAX prior to invoking the CPUID
+ instruction.
+ @param Eax Pointer to the 32-bit EAX value returned by the CPUID
+ instruction. This is an optional parameter that may be NULL.
+ @param Ebx Pointer to the 32-bit EBX value returned by the CPUID
+ instruction. This is an optional parameter that may be NULL.
+ @param Ecx Pointer to the 32-bit ECX value returned by the CPUID
+ instruction. This is an optional parameter that may be NULL.
+ @param Edx Pointer to the 32-bit EDX value returned by the CPUID
+ instruction. This is an optional parameter that may be NULL.
+
+ @return Index
+
+**/
UINT32
EFIAPI
AsmCpuid (
|