IntelFsp2Pkg: TempRamInit API should preserve EBX/RBX register.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4395

FSP specification defines the TempRamInit API preserved register list
which including EBX/RBX, however current implementation unexpectedly
overriding EBX/RBX register that should be fixed.

Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Signed-off-by: Chasel Chiu <chasel.chiu@intel.com>
Reviewed-by: Nate DeSimone <nathaniel.l.desimone@intel.com>
This commit is contained in:
Chasel Chiu 2023-03-31 00:09:27 -07:00 committed by mergify[bot]
parent fb89f62d27
commit af98f1fb03
2 changed files with 27 additions and 1 deletions

View File

@ -157,6 +157,9 @@ NextAddress:
; Use CpuId instruction (CPUID.01H:EDX.SSE[bit 25] = 1) to test
; whether the processor supports SSE instruction.
;
; Save EBX to MM2
;
movd mm2, ebx
mov eax, 1
cpuid
bt edx, 25
@ -169,6 +172,10 @@ NextAddress:
bt ecx, 19
jnc SseError
%endif
;
; Restore EBX from MM2
;
movd ebx, mm2
;
; Set OSFXSR bit (bit #9) & OSXMMEXCPT bit (bit #10)

View File

@ -255,6 +255,10 @@ NextAddress:
; Use CpuId instruction (CPUID.01H:EDX.SSE[bit 25] = 1) to test
; whether the processor supports SSE instruction.
;
; Save RBX to R11
; Save RCX to R10
;
mov r11, rbx
mov r10, rcx
mov rax, 1
cpuid
@ -266,7 +270,12 @@ NextAddress:
;
bt ecx, 19
jnc SseError
mov rcx, r10
;
; Restore RBX from R11
; Restore RCX from R10
;
mov rbx, r11
mov rcx, r10
;
; Set OSFXSR bit (bit #9) & OSXMMEXCPT bit (bit #10)
@ -284,6 +293,11 @@ NextAddress:
%endmacro
%macro ENABLE_AVX 0
;
; Save RBX to R11
; Save RCX to R10
;
mov r11, rbx
mov r10, rcx
mov eax, 1
cpuid
@ -307,6 +321,11 @@ EnableAvx:
xgetbv ; result in edx:eax
or eax, 00000006h ; Set XCR0 bit #1 and bit #2 to enable SSE state and AVX state
xsetbv
;
; Restore RBX from R11
; Restore RCX from R10
;
mov rbx, r11
mov rcx, r10
%endmacro