📄 nruntime.asm
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ret
el2c_1:
call enable_l2_cache_wt
el2c_2:
pop ax
ret
;-----------------------------------------------------------------------;
; GET_PIO_MODE_VALUE ;
;-----------------------------------------------------------------------;
; this routine returns the highest PIO mode supported by the hard disk.;
; input : ;
; ds:bx ptr to buffer containing the output of indentify drive ;
; command ;
; output: ;
; bl mode value ;
; si = 0000..drive supports IORDY ;
; = FFFF..drive does not support IORDY ;
; register destroyed : BX SI ;
;-----------------------------------------------------------------------;
public get_pio_mode_value
get_pio_mode_value proc near
push di
push cx
push ax
push dx
mov di,bx ; DS:DI = ptr to buffer
xor si,si ; SI = 0000..drive does not support IORDY
mov bl,ds:byte ptr [di+51*2+1]; bit15-8 of word 51 = mode
test ds:byte ptr [di+53*2],02h; bit-1 of word 53 = 1 ?
jz pio_00 ; word 64-70 are not valid
test ds:byte ptr [di+49*2+1],08h; bit-11 of word 49 = 1 ?
jz pio_no_iordy ; no, drive does not support IORDY
mov si,0ffffh ; SI = FFFF...drive supports IORDY
pio_no_iordy:
mov al,ds:byte ptr [di+64*2]; Get Advanced PIO mode value
test al,02h ; bit1 = 1 Mode 4 ?
jnz pio_mode_4 ; yes..
test al,01h ; bit0 = 1 Mode 3 ?
jz pio_00 ; no..
mov bl,3 ; Advanced PIO mode = 3
jmp short pio_00
pio_mode_4:
mov bl,4
pio_00:
pop dx
pop ax
pop cx
pop di
ret
get_pio_mode_value endp
COMMENT ~
pio_bit_check_table label byte
db 01h ; bit-0 for mode-0
db 02h ; bit-1 for mode-1
db 04h ; bit-2 for mode-2 to mode-4
db 04h ; bit-2 for mode-2 to mode-4
db 04h ; bit-2 for mode-2 to mode-4
public get_pio_mode_value
get_pio_mode_value proc near
push di
push cx
push ax
mov di,bx ; DS:DI = ptr to buffer
xor si,si ; SI = 0000..drive does not support IORDY
test ds:byte ptr [di+53*2],02h; bit-1 of word 53 = 1 ?
jnz pio_10 ; word 64-70 are valid
pio_02:
mov bl,ds:byte ptr [di+51*2+1]; bit15-8 of word 51 = mode
; word 64-67 are NOT valid..
; BL = mode value..
push bx
mov al,bl
mov bx,offset cgroup:pio_bit_check_table
xlat cgroup:pio_bit_check_table; AL = bit to be checked
pop bx
;;; test ds:byte ptr [di+01h],al ; bit set ?
;;; jnz pio_00
;;; mov bl,00h ; force mode-0
; BL = mode value..
jmp short pio_00
pio_10:
mov ax,ds:word ptr [di+67*2]; cycle time without IORDY
call get_pio_mode_from_cycle_time; BL = PIO mode
test ds:byte ptr [di+49*2+1],08h; bit-11 of word 49 = 1 ?
jz pio_00 ; no, drive does not support IORDY
; drive supports IORDY
mov ax,ds:word ptr [di+68*2]; cycle time with IORDY
call get_pio_mode_from_cycle_time; BL = PIO mode
; AX = cycle time, BL = calculated mode
; calculated mode value >= 3, check bit7-0 of word 64
; bit7-0 of word 64 is bit map definition..
; bit-0 = 1..mode 3 supported
; bit-1 = 1..mode 4 supported
mov cl,bl
sub cl,03h
jb pio_01 ; < mode 3, no need to check word 64
mov ch,1
shl ch,cl
test ds:byte ptr [di+64*2],ch; bit-x of word 64 = 0 ?
jz pio_02 ; drive does not support advanced PIO mode
pio_01:
mov si,0ffffh ; SI = FFFF...drive supports IORDY
pio_00:
pop ax
pop cx
pop di
ret
get_pio_mode_value endp
;---------------------------------------;
get_pio_mode_from_cycle_time:
; input : AX = cycle time
; output: BL = mode
; register destroyed..BX
xor bx,bx
or ax,ax ; cycle time = 00 => mode 0
jz gmfct_00
cmp ax,383
ja gmfct_00 ; mode 0
inc bx
cmp ax,240
ja gmfct_00 ; mode 1
inc bx
cmp ax,180
ja gmfct_00 ; mode 2
inc bx
cmp ax,120
ja gmfct_00 ; mode 3
inc bx ; mode 4
gmfct_00:
ret
;---------------------------------------;
get_pio_cycle_time_from_mode:
; input : BL = mode
; output: AX = cycle time
; register destroyed..AX
mov ax,120
cmp bl,4
ja gctfm_01 ; invalid mode, assume 600ns
jz gctfm_00 ; mode 4, 120ns
mov ax,180
cmp bl,3
jz gctfm_00 ; mode 3, 180ns
mov ax,240
cmp bl,2
jz gctfm_00 ; mode 2, 240ns
mov ax,383
cmp bl,1
jz gctfm_00 ; mode 1, 383ns
gctfm_01:
mov ax,600 ; mode 0, 600ns
gctfm_00:
ret
~
;-----------------------------------------------------------------------;
; GET_DMA_MODE_VALUE ;
;-----------------------------------------------------------------------;
; this routine returns the highest DMA mode supported by the hard disk.;
; input : ;
; ds:bx ptr to buffer containing the output of indentify drive ;
; command ;
; output: ;
; ECX Bit15-8 (CH) Non-Sync DMA mode information ;
; = 00 Non-Sync DMA not supported ;
; <>00 Non-Sync DMA mode ;
; Bit31-24 Sync DMA mode information ;
; = 00 Sync DMA not supported ;
; <>00 Sync DMA mode ;
; register destroyed : ECX Bit33-8 (i.e. CL can NOT be destroyed) ;
;-----------------------------------------------------------------------;
public get_dma_mode_value
get_dma_mode_value proc near
push si
push ax
push cx
; DS:BX = ptr to buffer
;;;; mov ch,00h ; init DMA mode value
xor ecx,ecx ; init DMA mode value
test ds:byte ptr [bx+49*2+1],01h; Non-Sync DMA supported ?
jz short check_sync_dma ; no
mov ch,ds:byte ptr [bx+52*2+1]; bit15-8 of word 52 = single word Non-Sync DMA mode
test ds:byte ptr [bx+53*2],02h; bit-1 of word 53 = 1 ?
jnz short non_sync_dma_00 ; word 64-70 are valid
; word 64-67 are NOT valid..
; CH = single word Non-Sync DMA mode value..
cmp ch,02h ; maxm is single word Non-Sync DMA mode-2
jbe short non_sync_dma_01 ; valid Non-Sync DMA mode
mov ch,00h ; force Non-Sync DMA mode-0
jmp short non_sync_dma_01
non_sync_dma_00:
; word 64-67 are valid..
mov al,ds:byte ptr [bx+62*2]; single word Non-Sync DMA transfer capibility
call get_dma_mode_from_capibility; CL = Non-Sync DMA mode
push cx
mov ax,ds:word ptr [bx+65*2]; multiword Non-Sync DMA cycle time
mov si,offset cgroup:non_sync_dma_mode_time_table
call get_dma_mode_from_cycle_time; CL = Non-Sync DMA mode
; CL = multiword Non-Sync DMA mode, check this value with word 63
; bit7-0 of word 63 is bit map definition..
; bit-0 = 1..multiword mode 0 supported
; bit-1 = 1..multiword mode 1 supported
; bit-2 = 1..multiword mode 2 supported
mov al,1
shl al,cl
test ds:byte ptr [bx+63*2],al; bit-x of word 63 = 0 ?
pop ax ; AL = single word Non-Sync DMA mode
jz short non_sync_dma_02 ; drive does not support multiword Non-Sync DMA mode
mov ch,cl
or ch,20h ; bit-5 = 1..multi word Non-Sync DMA
jmp short check_sync_dma
non_sync_dma_02:
; drive does not support found multiword Non-Sync DMA mode
mov ch,al ; use single word Non-Sync DMA mode
non_sync_dma_01:
or ch,10h ; bit-4 = 1..single word Non-Sync DMA
check_sync_dma:
; CH = Non-Sync DMA information
; check for Sync DMA
rol ecx,16
;----------------------------------------;
COMMENT ~ this code is according to Intel Spec Sep 20, 1996.
; Spec is changed in ATA Untra-DMA spec Oct 26, 1996.
test ds:byte ptr [bx+53*2],04h; bit-2 of word 53 = 1 ?
jz short sync_dma_00 ; word 84-85 are NOT valid, Sync DMA not supported
; word 84-85 are valid..Sync DMA supported
mov ax,ds:word ptr [bx+85*2]; Sync DMA cycle time
mov si,offset cgroup:sync_dma_mode_time_table
call get_dma_mode_from_cycle_time; CL = Sync DMA mode
; CL = Sync DMA mode, check this value with word 84
; bit7-0 of word 84 is bit map definition..
; bit-0 = 1..Sync DMA mode 0 supported
; bit-1 = 1..Sync DMA mode 1 supported
; bit-2 = 1..Sync DMA mode 2 supported
mov al,1
shl al,cl
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