diff --git a/MdePkg/Library/BaseLib/Ia32/EnablePaging64.asm b/MdePkg/Library/BaseLib/Ia32/EnablePaging64.asm index 6c9b0ea76b..97d859e966 100644 --- a/MdePkg/Library/BaseLib/Ia32/EnablePaging64.asm +++ b/MdePkg/Library/BaseLib/Ia32/EnablePaging64.asm @@ -26,9 +26,13 @@ .code InternalX86EnablePaging64 PROC - cli - mov [esp], @F ; offset for far retf - mov eax, cr4 + cli + + mov ebx, [esp + 4] ; save CS + mov eax, OFFSET cs_address + mov word ptr [eax], bx ; Update CS selector for far jump + + mov eax, cr4 or al, (1 SHL 5) mov cr4, eax ; enable PAE mov ecx, 0c0000080h @@ -37,19 +41,30 @@ InternalX86EnablePaging64 PROC wrmsr mov eax, cr0 bts eax, 31 - mov cr0, eax ; enable paging - retf -@@: ; long mode starts here + mov cr0, eax ; enable paging + retf + jmp go_to_long_mode +go_to_long_mode: + + ; + ; This is the next instruction after enabling paging. Jump to long mode + ; + db 067h + db 0eah ; Far Jump Offset:Selector to reload CS + dd OFFSET in_long_mode ; Offset is ensuing instruction boundary +cs_address: + dw 0h ; CS selector will be updated at runtime + +in_long_mode: ; now in long mode DB 67h, 48h - mov ebx, [esp] ; mov rbx, [esp] + mov ebx, [esp + 8] ; mov rbx, [esp] + DB 67h, 48h + mov ecx, [esp + 10h] ; mov rcx, [esp + 8] DB 67h, 48h - mov ecx, [esp + 8] ; mov rcx, [esp + 8] + mov edx, [esp + 18h] ; mov rdx, [esp + 10h] DB 67h, 48h - mov edx, [esp + 10h] ; mov rdx, [esp + 10h] - DB 67h, 48h - mov esp, [esp + 18h] ; mov rsp, [esp + 18h] + mov esp, [esp + 20h] ; mov rsp, [esp + 18h] DB 48h - add esp, -20h ; add rsp, -20h call ebx ; call rbx jmp $ InternalX86EnablePaging64 ENDP diff --git a/MdePkg/Library/BaseLib/X64/FlushCacheLine.asm b/MdePkg/Library/BaseLib/X64/FlushCacheLine.asm index 9978e734aa..44d7730947 100644 --- a/MdePkg/Library/BaseLib/X64/FlushCacheLine.asm +++ b/MdePkg/Library/BaseLib/X64/FlushCacheLine.asm @@ -24,7 +24,7 @@ .code ;------------------------------------------------------------------------------ -; VOID * +; VOID ; EFIAPI ; AsmFlushCacheLine ( ; IN VOID *LinearAddress