rockbox/firmware/target/coldfire/mpio/ata-as-mpio.S

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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: ata-as-coldfire.S 17847 2008-06-28 18:10:04Z bagder $
*
* Copyright (C) 2006 by Jens Arnold
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
.section .icode,"ax",@progbits
.equ .ata_port, 0x20000020
.equ .swapmask, 0x00FF00FF
.align 2
.global copy_read_sectors
.type copy_read_sectors,@function
/* Read a number of words from the ATA data port
*
* Utilises line bursts, assumes there is at least one full line to copy.
*
* Arguments:
* (4,%sp) - buffer address
* (8,%sp) - word count
*
* Register usage:
* %a0 - current address
* %a1 - end address
* %a2 - ata port
* %d0 - scratch
* %d1 - shift count
* %d2-%d6 - read buffers
*
* %d7 - byte swap scrach register
* %a3 - byte swap mask
*/
copy_read_sectors:
lea.l (-32, %sp), %sp
movem.l %d2-%d7/%a2-%a3, (%sp)
movem.l (36, %sp), %a0-%a1
add.l %a1, %a1
add.l %a0, %a1
lea.l .ata_port, %a2
lea.l .swapmask, %a3
move.l %a0, %d0
btst.l #0, %d0 /* 16-bit aligned? */
jeq .r_aligned /* yes, do word copy */
/* not 16-bit aligned */
subq.l #1, %a1 /* last byte is done unconditionally */
moveq.l #24, %d1 /* preload shift count */
move.w (%a2), %d2 /* load initial word */
move.b %d2, (%a0)+ /* write high byte of it, aligns dest addr */
/* we have byte swapped */
btst.l #1, %d0 /* longword aligned? (testing old d0 value!) */
bne.b .r_end_u_w1 /* yes, skip leading word handling */
swap %d2 /* move initial word up */
move.w (%a2), %d2 /* combine with second word */
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
move.l %d2, %d3
lsr.l #8, %d3
move.w %d3, (%a0)+ /* write bytes 2 and 3 as word */
.r_end_u_w1:
moveq.l #12, %d0
add.l %a0, %d0
and.l #0xFFFFFFF0,%d0 /* d0 == first line bound */
cmp.l %a0, %d0 /* any leading longwords? */
bls.b .r_end_u_l1 /* no: skip loop */
.r_loop_u_l1:
move.w (%a2), %d3 /* load first word */
swap %d3 /* move to upper 16 bit */
move.w (%a2), %d3 /* load second word */
/* byte swap d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
move.l %d3, %d4
lsl.l %d1, %d2
lsr.l #8, %d3
or.l %d3, %d2 /* combine old low byte with new top 3 bytes */
move.l %d2, (%a0)+ /* store as long */
move.l %d4, %d2
cmp.l %a0, %d0 /* run up to first line bound */
bhi.b .r_loop_u_l1
.r_end_u_l1:
lea.l (-14, %a1), %a1 /* adjust end addr. to 16 bytes/pass */
.r_loop_u_line:
move.w (%a2), %d3 /* load 1st word */
swap %d3 /* move to upper 16 bit */
move.w (%a2), %d3 /* load 2nd word */
/* byte swap d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
move.l %d3, %d0
lsl.l %d1, %d2
lsr.l #8, %d0
or.l %d0, %d2 /* combine old low byte with new top 3 bytes */
move.w (%a2), %d4 /* load 3rd word */
swap %d4 /* move to upper 16 bit */
move.w (%a2), %d4 /* load 4th word */
/* byte swap d4 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d4, %d7 /* d7 = .B.D */
eor.l %d7, %d4 /* d4 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d4 /* d4 = .A.C */
or.l %d7, %d4 /* d4 = BADC */
move.l %d4, %d0
lsl.l %d1, %d3
lsr.l #8, %d0
or.l %d0, %d3 /* combine old low byte with new top 3 bytes */
move.w (%a2), %d5 /* load 5th word */
swap %d5 /* move to upper 16 bit */
move.w (%a2), %d5 /* load 6th word */
/* byte swap d5 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d5, %d7 /* d7 = .B.D */
eor.l %d7, %d5 /* d5 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d5 /* d5 = .A.C */
or.l %d7, %d5 /* d5 = BADC */
move.l %d5, %d0
lsl.l %d1, %d4
lsr.l #8, %d0
or.l %d0, %d4 /* combine old low byte with new top 3 bytes */
move.w (%a2), %d6 /* load 7th word */
swap %d6 /* move to upper 16 bit */
move.w (%a2), %d6 /* load 8th word */
/* byte swap d6 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d6, %d7 /* d7 = .B.D */
eor.l %d7, %d6 /* d6 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d6 /* d6 = .A.C */
or.l %d7, %d6 /* d6 = BADC */
move.l %d6, %d0
lsl.l %d1, %d5
lsr.l #8, %d0
or.l %d0, %d5 /* combine old low byte with new top 3 bytes */
movem.l %d2-%d5, (%a0) /* store line */
lea.l (16, %a0), %a0
move.l %d6, %d2
cmp.l %a0, %a1 /* run up to last line bound */
bhi.b .r_loop_u_line
lea.l (12, %a1), %a1 /* readjust for longword loop */
cmp.l %a0, %a1 /* any trailing longwords? */
bls.b .r_end_u_l2 /* no: skip loop */
.r_loop_u_l2:
move.w (%a2), %d3 /* load first word */
swap %d3 /* move to upper 16 bit */
move.w (%a2), %d3 /* load second word */
/* byte swap d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
move.l %d3, %d4
lsl.l %d1, %d2
lsr.l #8, %d3
or.l %d3, %d2 /* combine old low byte with new top 3 bytes */
move.l %d2, (%a0)+ /* store as long */
move.l %d4, %d2
cmp.l %a0, %a1 /* run up to last long bound */
bhi.b .r_loop_u_l2
.r_end_u_l2:
addq.l #2, %a1 /* back to final end address */
cmp.l %a0, %a1 /* one word left? */
bls.b .r_end_u_w2
swap %d2 /* move old word to upper 16 bits */
move.w (%a2), %d2 /* load final word */
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
move.l %d2, %d3
lsr.l #8, %d3
move.w %d3, (%a0)+ /* write bytes 2 and 3 as word */
.r_end_u_w2:
move.b %d2, (%a0)+ /* store final byte */
bra.w .r_exit
/* 16-bit aligned */
.r_aligned:
btst.l #1, %d0 /* longword aligned? */
beq.b .r_end_a_w1 /* yes, skip leading word handling */
/* copy initial word */
/* initial word has to be swapped */
move.w (%a2), %d7
move.b %d7, (%a0)+
lsr.l #8, %d7
move.b %d7, (%a0)+
.r_end_a_w1:
moveq.l #12, %d0
add.l %a0, %d0
and.l #0xFFFFFFF0,%d0 /* d0 == first line bound */
cmp.l %a0, %d0 /* any leading longwords? */
bls.b .r_end_a_l1 /* no: skip loop */
.r_loop_a_l1:
move.w (%a2), %d1 /* load first word */
swap %d1 /* move it to upper 16 bits */
move.w (%a2), %d1 /* load second word */
/* byte swap d1 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
move.l %d1, (%a0)+ /* store as long */
cmp.l %a0, %d0 /* run up to first line bound */
bhi.b .r_loop_a_l1
.r_end_a_l1:
lea.l (-14, %a1), %a1 /* adjust end addr. to 16 bytes/pass */
.r_loop_a_line:
move.w (%a2), %d0 /* load 1st word */
swap %d0 /* move it to upper 16 bits */
move.w (%a2), %d0 /* load 2nd word */
/* byte swap d0 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d0, %d7 /* d7 = .B.D */
eor.l %d7, %d0 /* d0 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d0 /* d0 = .A.C */
or.l %d7, %d0 /* d0 = BADC */
move.w (%a2), %d1 /* load 3rd word */
swap %d1 /* move it to upper 16 bits */
move.w (%a2), %d1 /* load 4th word */
/* byte swap d1 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
move.w (%a2), %d2 /* load 5th word */
swap %d2 /* move it to upper 16 bits */
move.w (%a2), %d2 /* load 6th word */
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
move.w (%a2), %d3 /* load 7th word */
swap %d3 /* move it to upper 16 bits */
move.w (%a2), %d3 /* load 8th word */
/* byte swap d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
movem.l %d0-%d3, (%a0) /* store line */
lea.l (16, %a0), %a0
cmp.l %a0, %a1 /* run up to last line bound */
bhi.b .r_loop_a_line
lea.l (12, %a1), %a1 /* readjust for longword loop */
cmp.l %a0, %a1 /* any trailing longwords? */
bls.b .r_end_a_l2 /* no: skip loop */
.r_loop_a_l2:
move.w (%a2), %d1 /* read first word */
swap %d1 /* move it to upper 16 bits */
move.w (%a2), %d1 /* read second word */
/* byte swap d1 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
move.l %d1, (%a0)+ /* store as long */
cmp.l %a0, %a1 /* run up to last long bound */
bhi.b .r_loop_a_l2
.r_end_a_l2:
addq.l #2, %a1 /* back to final end address */
cmp.l %a0, %a1 /* one word left? */
bls.b .r_end_a_w2
/* copy final word */
/* final word has to be swapped */
move.w (%a2), %d7
move.b %d7, (%a0)+
lsr.l #8, %d7
move.b %d7, (%a0)+
.r_end_a_w2:
.r_exit:
movem.l (%sp), %d2-%d7/%a2-%a3
lea.l (32, %sp), %sp
rts
.r_end:
.size copy_read_sectors,.r_end-copy_read_sectors
.align 2
.global copy_write_sectors
.type copy_write_sectors,@function
#if 0
/* Write a number of words to the ATA data port
*
* Utilises line bursts, assumes there is at least one full line to copy.
*
* Arguments:
* (4,%sp) - buffer address
* (8,%sp) - word count
*
* Register usage:
* %a0 - current address
* %a1 - end address
* %a2 - ata port
* %d0 - scratch
* %d1 - shift count
* %d2-%d6 - read buffers
*
* %d7 - swap scrach
* %a3 - swap mask
*/
copy_write_sectors:
lea.l (-32, %sp), %sp
movem.l %d2-%d7/%a2-%a3, (%sp)
movem.l (36, %sp), %a0-%a1
add.l %a1, %a1
add.l %a0, %a1
lea.l .ata_port, %a2
lea.l .swapmask, %a3
move.l %a0, %d0
btst.l #0, %d0 /* 16-bit aligned? */
beq .w_aligned /* yes, do word copy */
/* not 16-bit aligned */
subq.l #1, %a1 /* last byte is done unconditionally */
moveq.l #24, %d1 /* preload shift count */
move.b (%a0)+, %d2
btst.l #1, %d0 /* longword aligned? (testing old d0 value!) */
bne.b .w_end_u_w1 /* yes, skip leading word handling */
swap %d2
move.w (%a0)+, %d2
move.l %d2, %d3
lsr.l #8, %d3
/* low word of %d3 has to be byte swaped */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
move.w %d3, (%a2)
.w_end_u_w1:
moveq.l #12, %d0
add.l %a0, %d0
and.l #0xFFFFFFF0,%d0 /* d0 == first line bound */
cmp.l %a0, %d0 /* any leading longwords? */
bls.b .w_end_u_l1 /* no: skip loop */
.w_loop_u_l1:
move.l (%a0)+, %d3
move.l %d3, %d4
lsl.l %d1, %d2
lsr.l #8, %d3
or.l %d3, %d2
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
swap %d2
move.w %d2, (%a2)
swap %d2
move.w %d2, (%a2)
move.l %d4, %d2
cmp.l %a0, %d0 /* run up to first line bound */
bhi.b .w_loop_u_l1
.w_end_u_l1:
lea.l (-14, %a1), %a1 /* adjust end addr. to 16 bytes/pass */
.w_loop_u_line:
movem.l (%a0), %d3-%d6
lea.l (16, %a0), %a0
move.l %d3, %d0
lsl.l %d1, %d2
lsr.l #8, %d0
or.l %d0, %d2
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
swap %d2
move.w %d2, (%a2)
swap %d2
move.w %d2, (%a2)
move.l %d4, %d0
lsl.l %d1, %d3
lsr.l #8, %d0
or.l %d0, %d3
/* byte swap d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
swap %d3
move.w %d3, (%a2)
swap %d3
move.w %d3, (%a2)
move.l %d5, %d0
lsl.l %d1, %d4
lsr.l #8, %d0
or.l %d0, %d4
/* byte swap d4 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d4, %d7 /* d7 = .B.D */
eor.l %d7, %d4 /* d4 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d4 /* d4 = .A.C */
or.l %d7, %d4 /* d4 = BADC */
swap %d4
move.w %d4, (%a2)
swap %d4
move.w %d4, (%a2)
move.l %d6, %d0
lsl.l %d1, %d5
lsr.l #8, %d0
or.l %d0, %d5
/* byte swap d5 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d5, %d7 /* d7 = .B.D */
eor.l %d7, %d5 /* d5 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d5 /* d5 = .A.C */
or.l %d7, %d5 /* d5 = BADC */
swap %d5
move.w %d5, (%a2)
swap %d5
move.w %d5, (%a2)
move.l %d6, %d2
cmp.l %a0, %a1 /* run up to last line bound */
bhi.b .w_loop_u_line
lea.l (12, %a1), %a1 /* readjust for longword loop */
cmp.l %a0, %a1 /* any trailing longwords? */
bls.b .w_end_u_l2 /* no: skip loop */
.w_loop_u_l2:
move.l (%a0)+, %d3
move.l %d3, %d4
lsl.l %d1, %d2
lsr.l #8, %d3
or.l %d3, %d2
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
swap %d2
move.w %d2, (%a2)
swap %d2
move.w %d2, (%a2)
move.l %d4, %d2
cmp.l %a0, %a1 /* run up to first line bound */
bhi.b .w_loop_u_l2
.w_end_u_l2:
addq.l #2, %a1 /* back to final end address */
cmp.l %a0, %a1 /* one word left? */
bls.b .w_end_u_w2
swap %d2
move.w (%a0)+, %d2
move.l %d2, %d3
lsr.l #8, %d3
/* byte swap d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
move.w %d3, (%a2)
.w_end_u_w2:
lsl.l #8, %d2
move.b (%a0)+, %d2
/* byte swap d2 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
move.w %d2, (%a2)
bra.w .w_exit
/* 16-bit aligned */
.w_aligned:
btst.l #1, %d0
beq.b .w_end_a_w1
/* this has to be byte swaped */
/* copy initial word */
move.w (%a0)+, %d1
/* byte swap d1 */
move.l %a3, %d7 /* d7 = $00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
move.w %d1, (%a2)
.w_end_a_w1:
moveq.l #12, %d0
add.l %a0, %d0
and.l #0xFFFFFFF0,%d0 /* d0 == first line bound */
cmp.l %a0, %d0 /* any leading longwords? */
bls.b .w_end_a_l1 /* no: skip loop */
.w_loop_a_l1:
move.l (%a0)+, %d1
/* byte swap d1 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
swap %d1
move.w %d1, (%a2)
swap %d1
move.w %d1, (%a2)
cmp.l %a0, %d0 /* run up to first line bound */
bhi.b .w_loop_a_l1
.w_end_a_l1:
lea.l (-14, %a1), %a1 /* adjust end addr. to 16 bytes/pass */
.w_loop_a_line:
movem.l (%a0), %d0-%d3
/* byte swap d0-d3 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d0, %d7 /* d7 = .B.D */
eor.l %d7, %d0 /* d0 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d0 /* d0 = .A.C */
or.l %d7, %d0 /* d0 = BADC */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d2, %d7 /* d7 = .B.D */
eor.l %d7, %d2 /* d2 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d2 /* d2 = .A.C */
or.l %d7, %d2 /* d2 = BADC */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d3, %d7 /* d7 = .B.D */
eor.l %d7, %d3 /* d3 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d3 /* d3 = .A.C */
or.l %d7, %d3 /* d3 = BADC */
lea.l (16, %a0), %a0
swap %d0
move.w %d0, (%a2)
swap %d0
move.w %d0, (%a2)
swap %d1
move.w %d1, (%a2)
swap %d1
move.w %d1, (%a2)
swap %d2
move.w %d2, (%a2)
swap %d2
move.w %d2, (%a2)
swap %d3
move.w %d3, (%a2)
swap %d3
move.w %d3, (%a2)
cmp.l %a0, %a1 /* run up to last line bound */
bhi.b .w_loop_a_line
lea.l (12, %a1), %a1 /* readjust for longword loop */
cmp.l %a0, %a1 /* any trailing longwords? */
bls.b .w_end_a_l2 /* no: skip loop */
.w_loop_a_l2:
move.l (%a0)+, %d1
/* byte swap d1 */
move.l %a3, %d7 /* d7 = 0x00FF00FF */
and.l %d1, %d7 /* d7 = .B.D */
eor.l %d7, %d1 /* d1 = A.C. */
lsl.l #8, %d7 /* d7 = B.D. */
lsr.l #8, %d1 /* d1 = .A.C */
or.l %d7, %d1 /* d1 = BADC */
swap %d1
move.w %d1, (%a2)
swap %d1
move.w %d1, (%a2)
cmp.l %a0, %a1 /* run up to first line bound */
bhi.b .w_loop_a_l2
.w_end_a_l2:
addq.l #2, %a1 /* back to final end address */
cmp.l %a0, %a1 /* one word left? */
bls.b .w_end_a_w2
/* this has to be byte swaped */
/* copy final word */
move.w (%a0)+, %d0
move.l %a3, %d7
and.l %d0, %d7
eor.l %d7, %d0
lsl.l #8, %d7
lsr.l #8, %d0
or.l %d7, %d0
move.w %d0, (%a2)
.w_end_a_w2:
.w_exit:
movem.l (%sp), %d2-%d7/%a2-%a3
lea.l (32, %sp), %sp
rts
.w_end:
.size copy_write_sectors,.w_end-copy_write_sectors
#endif