.global get_cpu_brand_string

.type get_cpu_brand_string, @function

get_cpu_brand_string:
    pushad                      # Save all general-purpose registers

    mov ebx, eax                # Save buffer pointer to ebx

    mov eax, 0x80000000
    cpuid
    cmp eax, 0x80000004         # Check if brand string is supported
    jb .not_supported

    mov esi, ebx                # Copy address to ESI

    mov eax, 0x80000002
    cpuid
    mov [esi], eax
    mov [esi + 4], ebx
    mov [esi + 8], ecx
    mov [esi + 12], edx

    mov eax, 0x80000003
    cpuid
    mov [esi + 16], eax
    mov [esi + 20], ebx
    mov [esi + 24], ecx
    mov [esi + 28], edx

    mov eax, 0x80000004
    cpuid
    mov [esi + 32], eax
    mov [esi + 36], ebx
    mov [esi + 40], ecx
    mov [esi + 44], edx

    jmp .done

.not_supported:
    mov byte [ebx], 0           # Null-terminate if not supported

.done:
    popad
    ret