/*
* linux/arch/arm26/lib/ll_char_wr.S
*
* Copyright (C) 1995, 1996 Russell King.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Speedups & 1bpp code (C) 1996 Philip Blundell & Russell King.
*
* 10-04-96 RMK Various cleanups & reduced register usage.
* 08-04-98 RMK Shifts re-ordered
*/
@ Regs: [] = corruptible
@ {} = used
@ () = do not use
#include <linux/linkage.h>
#include <asm/assembler.h>
.text
#define BOLD 0x01
#define ITALIC 0x02
#define UNDERLINE 0x04
#define FLASH 0x08
#define INVERSE 0x10
LC0: .word bytes_per_char_h
.word video_size_row
.word acorndata_8x8
.word con_charconvtable
ENTRY(ll_write_char)
stmfd sp!, {r4 - r7, lr}
@
@ Smashable regs: {r0 - r3}, [r4 - r7], (r8 - fp), [ip], (sp), [lr], (pc)
@
eor ip, r1, #UNDERLINE << 9
/*
* calculate colours
*/
tst r1, #INVERSE << 9
moveq r2, r1, lsr #16
moveq r3, r1, lsr #24
movne r2, r1, lsr #24
movne r3, r1, lsr #16
and r3, r3, #255
and r2, r2, #255
/*
* calculate offset into character table
*/
mov r1, r1, lsl #23
mov r1, r1, lsr #20
/*
* calculate offset required for each row [maybe I should make this an argument to this fn.
* Have to see what the register usage is like in the calling routines.
*/
adr r4, LC0
ldmia r4, {r4, r5, r6, lr}
ldr r4, [r4]
ldr r5, [r5]
/*
* Go to resolution-dependent routine...
*/
cmp r4, #4
blt Lrow1bpp
eor r2, r3, r2 @ Create eor mask to change colour from bg
orr r3, r3, r3, lsl #8 @ to fg.
orr r3, r3, r3, lsl #16
add r0, r0, r5, lsl #3 @ Move to bottom of character
add r1, r1, #7
ldrb r7, [r6, r1]
tst ip, #UNDERLINE << 9
eoreq r7, r7, #255
teq r4, #8
beq Lrow8bpplp
@
@ Smashable regs: {r0 - r3}, [r4], {r5 - r7}, (r8 - fp), [ip], (sp), {lr}, (pc)
@
orr r3, r3, r3, lsl #4
Lrow4bpplp: ldr r7, [lr, r7, lsl #2]
mul r7, r2, r7
tst r1, #7 @ avoid using r7 directly after
eor ip, r3, r7
str ip, [r0, -r5]!
LOADREGS(eqfd, sp!, {r4 - r7, pc})
sub r1, r1, #1
ldrb r7, [r6, r1]
ldr r7, [lr, r7, lsl #2]
mul r7, r2, r7
tst r1, #7 @ avoid using r7 directly after
eor ip, r3, r7
str ip, [r0, -r5]!
subne r1, r1, #1
ldrneb r7, [r6, r1]
bne Lrow4bpplp
LOADREGS(fd, sp!, {r4 - r7, pc})
@
@ Smashable regs: {r0 - r3}, [r4], {r5 - r7}, (r8 - fp), [ip], (sp), {lr}, (pc)
@
Lrow8bpplp: mov ip, r7, lsr #4
ldr ip, [lr, ip, lsl #2]
mul r4, r2, ip
and ip, r7, #15 @ avoid r4
ldr ip, [lr, ip, lsl #2] @ avoid r4
mul ip, r2, ip @ avoid r4
eor r4, r3, r4 @ avoid ip
tst r1, #7 @ avoid ip
sub r0, r0, r5 @ avoid ip
eor ip, r3, ip
stmia r0, {r4, ip}
LOADREGS(eqfd, sp!, {r4 - r7, pc})
sub r1, r1, #1
ldrb r7, [r6, r1]
mov ip, r7, lsr #4
ldr ip, [lr, ip, lsl #2]
mul r4, r2, ip
and ip, r7, #15 @ avoid r4
ldr ip, [lr, ip, lsl #2] @ avoid r4
mul ip, r2, ip @ avoid r4
eor r4, r3, r4 @ avoid ip
tst r1, #7 @ avoid ip
sub r0, r0, r5 @ avoid ip
eor ip, r3, ip
stmia r0, {r4, ip}
subne r1, r1, #1
ldrneb r7, [r6, r1]
bne Lrow8bpplp
LOADREGS(fd, sp!, {r4 - r7, pc})
@
@ Smashable regs: {r0 - r3}, [r4], {r5, r6}, [r7], (r8 - fp), [ip], (sp), [lr], (pc)
@
Lrow1bpp: add r6, r6, r1
ldmia r6, {r4, r7}
tst ip, #INVERSE << 9
mvnne r4, r4
mvnne r7, r7
strb r4, [r0], r5
mov r4, r4, lsr #8
strb r4, [r0], r5
mov r4, r4, lsr #8
strb r4, [r0], r5
mov r4, r4, lsr #8
strb r4, [r0], r5
strb r7, [r0], r5
mov r7, r7, lsr #8
strb r7, [r0], r5
mov r7, r7, lsr #8
strb r7, [r0], r5
mov r7, r7, lsr #8
tst ip, #UNDERLINE << 9
mvneq r7, r7
strb r7, [r0], r5
LOADREGS(fd, sp!, {r4 - r7, pc})
.bss
ENTRY(con_charconvtable)
.space 1024
