tge/engine/platform/platformCPUInfo.asm
2025-02-17 23:17:30 -06:00

112 lines
2.9 KiB
NASM
Executable File

;-----------------------------------------------------------------------------
; Torque Game Engine
; Copyright (C) GarageGames.com, Inc.
;-----------------------------------------------------------------------------
segment .text
; syntax: export_fn <function name>
%macro export_fn 1
%ifdef LINUX
; No underscore needed for ELF object files
global %1
%1:
%else
global _%1
_%1:
%endif
%endmacro
; push registers
%macro pushreg 0
; pushad
push ebx
push ebp
push esi
push edi
%endmacro
; pop registers
%macro popreg 0
pop edi
pop esi
pop ebp
pop ebx
; popad
%endmacro
; void detectX86CPUInfo(char *vendor, U32 *processor, U32 *properties);
export_fn detectX86CPUInfo
push ebp
mov ebp, esp
pushreg
push edx
push ecx
pushfd
pushfd ; save EFLAGS to stack
pop eax ; move EFLAGS into EAX
mov ebx, eax
xor eax, 0x200000 ; flip bit 21
push eax
popfd ; restore EFLAGS
pushfd
pop eax
cmp eax, ebx
jz EXIT ; doesn't support CPUID instruction
;
; get vendor information using CPUID eax == 0
xor eax, eax
cpuid
; store the vendor tag (12 bytes in ebx, edx, ecx) in the first parameter,
; which should be a char[13]
push eax ; save eax
mov eax, [ebp+8] ; store the char* address in eax
mov [eax], ebx ; move ebx into the first 4 bytes
add eax, 4 ; advance the char* 4 bytes
mov [eax], edx ; move edx into the next 4 bytes
add eax, 4 ; advance the char* 4 bytes
mov [eax], ecx ; move ecx into the last 4 bytes
pop eax ; restore eax
; get generic extended CPUID info
mov eax, 1
cpuid ; eax=1, so cpuid queries feature information
and eax, 0x0FF0
push ecx
mov ecx, [ebp+12]
mov [ecx], eax ; just store the model bits in processor param
mov ecx, [ebp+16]
mov [ecx], edx ; set properties param
pop ecx
; want to check for 3DNow(tm).
; need to see if extended cpuid functions present.
mov eax, 0x80000000
cpuid
cmp eax, 0x80000000
jbe MAYBE_3DLATER
mov eax, 0x80000001
cpuid
; 3DNow if bit 31 set -> put bit in our properties
and edx, 0x80000000
push eax
mov eax, [ebp+16]
or [eax], edx
pop eax
MAYBE_3DLATER:
EXIT:
popfd
pop ecx
pop edx
popreg
pop ebp
ret