Load into SMRAM, not just video RAM.

[netwatch.git] / aseg / aseg.asm

diff --git a/aseg/aseg.asm b/aseg/aseg.asm
index 244cafc359f3ae87669952727d914f2d43b9f0ed..a6f71c20cd79c5eed1b581654e9bfde5edaabb2a 100644 (file)
--- a/aseg/aseg.asm
+++ b/aseg/aseg.asm
@@ -1,9 +1,9 @@
        org 0xA8000
 [bits 16]
 entry:
        org 0xA8000
 [bits 16]
 entry:

-       mov ax, 0xA800
-       mov ds, ax              ; Take us out of flat unreal mode, and
-       mov es, ax              ; put us in true real mode.
+       mov ax, 0xA800                  ; Take us out of flat unreal mode,
+       mov ds, ax                      ; and put us in true real mode.
+       mov es, ax

        mov fs, ax
        mov gs, ax
        mov ss, ax
        mov fs, ax
        mov gs, ax
        mov ss, ax


@@ -21,114 +21,39 @@ continue:
        mov fs, ax
        mov gs, ax
        mov ss, ax
        mov fs, ax
        mov gs, ax
        mov ss, ax

-       mov esp, [dataptr]
-
-;      mov al, [cstat]
-;      add al, 1
-;      out 0x80, al
-;      mov [cstat], al
-       
-       mov dx, 0xCF8                   ; save off the old config value
-       in dword eax, dx
-       mov [esp-4], eax
-       
-       mov eax, 0x80000070             ; load in smramc
-       out dx, eax
-       mov dx, 0xCFC
-       in byte al, dx
-       mov [esp-5], al
-       and al, 0xF3                    ; Allow graphics access
-       or al, 0x08
-       out dx, al
-       
-       xor eax, eax
-       mov dx, 0x3D4
-       in byte al, dx
-       mov [esp-6], al                 ; save off the old VGA command
-       mov al, 0xC
-       out dx, al
-       inc dx
-       in al, dx
-       mov ah, al
-       dec dx
-       mov al, 0xD
-       out dx, al
-       inc dx
-       in al, dx
-       shl eax, 1
-       add eax, 0xB8000                ; yay
-       mov byte [eax+0], '1'
-       mov byte [eax+1], 0x1F
-       mov byte [eax+2], '5'
-       mov byte [eax+3], 0x1F
-       mov byte [eax+4], '-'
-       mov byte [eax+5], 0x1F
-       mov byte [eax+6], '4'
-       mov byte [eax+7], 0x1F
-       mov byte [eax+8], '1'
-       mov byte [eax+9], 0x1F
-       mov byte [eax+10], '2'
-       mov byte [eax+11], 0x1F
-       
-       mov dx, 0x3D4                   ; restore the old stuff
-       mov al, [esp-6]
-       out dx, al
-
-       mov dx, 0xCFC                   ; restore smramc
-       mov al, [esp-5]
-       out dx, al
-
-       mov dx, 0xCF8                   ; restore the old PCI config value
-       mov eax, [esp-4]
-       out dx, eax
+       mov esp, [dataptr]              ; Load stack pointer.

 
 

-       mov al, [needclear]
-       cmp al, 0
-       jz noclear
-       mov al, 0                       ; clear BSS
+       mov al, [needclear]             ; Has the aseg been run before?
+       cmp al, 0                       ; If so,
+       jz noclear                      ; don't clear BSS.
+       mov al, 0                       ; Otherwise, clear BSS.

        mov edi, [dataptr+4]
        mov ecx, [dataptr+8]
        rep stosb
        mov [needclear], al
        
 noclear:
        mov edi, [dataptr+4]
        mov ecx, [dataptr+8]
        rep stosb
        mov [needclear], al
        
 noclear:

-       mov eax, [dataptr+12]           ; jump into C
-       call eax
-
-       mov al, 0x40                    ; ack the periodic IRQ
-       mov dx, 0x834
-       out dx, al
-       
-       mov dx, 0x830                   ; now ack the SMI itself
-       in al, dx
-       or al, 0x02
-       and al, 0xBF
-       out dx, al
-       or al, 0x40
-       out dx, al
+       mov eax, [dataptr+12]           ; Load target jump address
+       call eax                        ; then jump into C.

 
        rsm                             ; and leave SMM
 
 
        rsm                             ; and leave SMM
 

-needclear:
-       db 0x01
-

        align 0x4
 gdtr:
        align 0x4
 gdtr:

-       db 0x27, 0x00
+       db 0x17, 0x00

        dd gdt
        align 0x4
 gdt:
        dd gdt
        align 0x4
 gdt:

-       db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+       db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00       ; initial null entry

        db 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x93, 0xCF, 0x00       ; data segment
        db 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x9B, 0xCF, 0x00       ; code segment
        db 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x93, 0xCF, 0x00       ; data segment
        db 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x9B, 0xCF, 0x00       ; code segment

-       db 0xFF, 0xFF, 0x00, 0x80, 0x0A, 0x9B, 0xCF, 0x00       ; code segment for trampoline

 
 

-cstat:
-       db 0x00
+needclear:
+       db 0x01

 
 

-TIMES   512-($-$$) DB 0

 dataptr:
        ; 4 bytes of stack top
        ; 4 bytes of BSS start
        ; 4 bytes of BSS length
 dataptr:
        ; 4 bytes of stack top
        ; 4 bytes of BSS start
        ; 4 bytes of BSS length

-       ; 4 bytes of C entry point
\ No newline at end of file
+       ; 4 bytes of C entry point
+       ; These show up