linux/arch/avr32/lib/csum_partial_copy_generic.S

100 lines
1.7 KiB
ArmAsm

/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* 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 <asm/errno.h>
#include <asm/asm.h>
/*
* unsigned int csum_partial_copy_generic(const char *src, char *dst, int len
* int sum, int *src_err_ptr,
* int *dst_err_ptr)
*
* Copy src to dst while checksumming, otherwise like csum_partial.
*/
.macro ld_src size, reg, ptr
9999: ld.\size \reg, \ptr
.section __ex_table, "a"
.long 9999b, fixup_ld_src
.previous
.endm
.macro st_dst size, ptr, reg
9999: st.\size \ptr, \reg
.section __ex_table, "a"
.long 9999b, fixup_st_dst
.previous
.endm
.text
.global csum_partial_copy_generic
.type csum_partial_copy_generic,"function"
.align 1
csum_partial_copy_generic:
pushm r4-r7,lr
/* The inner loop */
1: sub r10, 4
brlt 5f
2: ld_src w, r5, r12++
st_dst w, r11++, r5
add r9, r5
acr r9
sub r10, 4
brge 2b
/* return if we had a whole number of words */
5: sub r10, -4
brne 7f
6: mov r12, r9
popm r4-r7,pc
/* handle additional bytes at the tail */
7: mov r5, 0
mov r4, 32
8: ld_src ub, r6, r12++
st_dst b, r11++, r6
lsl r5, 8
sub r4, 8
bfins r5, r6, 0, 8
sub r10, 1
brne 8b
lsl r5, r5, r4
add r9, r5
acr r9
rjmp 6b
/* Exception handler */
.section .fixup,"ax"
.align 1
fixup_ld_src:
mov r9, -EFAULT
cp.w r8, 0
breq 1f
st.w r8[0], r9
1: /*
* TODO: zero the complete destination - computing the rest
* is too much work
*/
mov r9, 0
rjmp 6b
fixup_st_dst:
mov r9, -EFAULT
lddsp r8, sp[20]
cp.w r8, 0
breq 1f
st.w r8[0], r9
1: mov r9, 0
rjmp 6b
.previous