acrn-kernel/arch/arm/lib/io-readsb.S

123 lines
2.4 KiB
ArmAsm

/*
* linux/arch/arm/lib/io-readsb.S
*
* Copyright (C) 1995-2000 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.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
.Linsb_align: rsb ip, ip, #4
cmp ip, r2
movgt ip, r2
cmp ip, #2
ldrb r3, [r0]
strb r3, [r1], #1
ldrgeb r3, [r0]
strgeb r3, [r1], #1
ldrgtb r3, [r0]
strgtb r3, [r1], #1
subs r2, r2, ip
bne .Linsb_aligned
ENTRY(__raw_readsb)
teq r2, #0 @ do we have to check for the zero len?
moveq pc, lr
ands ip, r1, #3
bne .Linsb_align
.Linsb_aligned: stmfd sp!, {r4 - r6, lr}
subs r2, r2, #16
bmi .Linsb_no_16
.Linsb_16_lp: ldrb r3, [r0]
ldrb r4, [r0]
ldrb r5, [r0]
mov r3, r3, put_byte_0
ldrb r6, [r0]
orr r3, r3, r4, put_byte_1
ldrb r4, [r0]
orr r3, r3, r5, put_byte_2
ldrb r5, [r0]
orr r3, r3, r6, put_byte_3
ldrb r6, [r0]
mov r4, r4, put_byte_0
ldrb ip, [r0]
orr r4, r4, r5, put_byte_1
ldrb r5, [r0]
orr r4, r4, r6, put_byte_2
ldrb r6, [r0]
orr r4, r4, ip, put_byte_3
ldrb ip, [r0]
mov r5, r5, put_byte_0
ldrb lr, [r0]
orr r5, r5, r6, put_byte_1
ldrb r6, [r0]
orr r5, r5, ip, put_byte_2
ldrb ip, [r0]
orr r5, r5, lr, put_byte_3
ldrb lr, [r0]
mov r6, r6, put_byte_0
orr r6, r6, ip, put_byte_1
ldrb ip, [r0]
orr r6, r6, lr, put_byte_2
orr r6, r6, ip, put_byte_3
stmia r1!, {r3 - r6}
subs r2, r2, #16
bpl .Linsb_16_lp
tst r2, #15
ldmeqfd sp!, {r4 - r6, pc}
.Linsb_no_16: tst r2, #8
beq .Linsb_no_8
ldrb r3, [r0]
ldrb r4, [r0]
ldrb r5, [r0]
mov r3, r3, put_byte_0
ldrb r6, [r0]
orr r3, r3, r4, put_byte_1
ldrb r4, [r0]
orr r3, r3, r5, put_byte_2
ldrb r5, [r0]
orr r3, r3, r6, put_byte_3
ldrb r6, [r0]
mov r4, r4, put_byte_0
ldrb ip, [r0]
orr r4, r4, r5, put_byte_1
orr r4, r4, r6, put_byte_2
orr r4, r4, ip, put_byte_3
stmia r1!, {r3, r4}
.Linsb_no_8: tst r2, #4
beq .Linsb_no_4
ldrb r3, [r0]
ldrb r4, [r0]
ldrb r5, [r0]
ldrb r6, [r0]
mov r3, r3, put_byte_0
orr r3, r3, r4, put_byte_1
orr r3, r3, r5, put_byte_2
orr r3, r3, r6, put_byte_3
str r3, [r1], #4
.Linsb_no_4: ands r2, r2, #3
ldmeqfd sp!, {r4 - r6, pc}
cmp r2, #2
ldrb r3, [r0]
strb r3, [r1], #1
ldrgeb r3, [r0]
strgeb r3, [r1], #1
ldrgtb r3, [r0]
strgtb r3, [r1]
ldmfd sp!, {r4 - r6, pc}