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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <linux/export.h>
#include <asm/alternative-asm.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/cpu.h>
#include <asm/regdef.h>
SYM_FUNC_START(memcpy)
/*
* Some CPUs support hardware unaligned access
*/
ALTERNATIVE "b __memcpy_generic", \
"b __memcpy_fast", CPU_FEATURE_UAL
SYM_FUNC_END(memcpy)
_ASM_NOKPROBE(memcpy)
EXPORT_SYMBOL(memcpy)
/*
* void *__memcpy_generic(void *dst, const void *src, size_t n)
*
* a0: dst
* a1: src
* a2: n
*/
SYM_FUNC_START(__memcpy_generic)
move a3, a0
beqz a2, 2f
1: ld.b t0, a1, 0
st.b t0, a0, 0
addi.d a0, a0, 1
addi.d a1, a1, 1
addi.d a2, a2, -1
bgt a2, zero, 1b
2: move a0, a3
jr ra
SYM_FUNC_END(__memcpy_generic)
_ASM_NOKPROBE(__memcpy_generic)
.align 5
SYM_FUNC_START_NOALIGN(__memcpy_small)
pcaddi t0, 8
slli.d a2, a2, 5
add.d t0, t0, a2
jr t0
.align 5
0: jr ra
.align 5
1: ld.b t0, a1, 0
st.b t0, a0, 0
jr ra
.align 5
2: ld.h t0, a1, 0
st.h t0, a0, 0
jr ra
.align 5
3: ld.h t0, a1, 0
ld.b t1, a1, 2
st.h t0, a0, 0
st.b t1, a0, 2
jr ra
.align 5
4: ld.w t0, a1, 0
st.w t0, a0, 0
jr ra
.align 5
5: ld.w t0, a1, 0
ld.b t1, a1, 4
st.w t0, a0, 0
st.b t1, a0, 4
jr ra
.align 5
6: ld.w t0, a1, 0
ld.h t1, a1, 4
st.w t0, a0, 0
st.h t1, a0, 4
jr ra
.align 5
7: ld.w t0, a1, 0
ld.w t1, a1, 3
st.w t0, a0, 0
st.w t1, a0, 3
jr ra
.align 5
8: ld.d t0, a1, 0
st.d t0, a0, 0
jr ra
SYM_FUNC_END(__memcpy_small)
_ASM_NOKPROBE(__memcpy_small)
/*
* void *__memcpy_fast(void *dst, const void *src, size_t n)
*
* a0: dst
* a1: src
* a2: n
*/
SYM_FUNC_START(__memcpy_fast)
sltui t0, a2, 9
bnez t0, __memcpy_small
add.d a3, a1, a2
add.d a2, a0, a2
ld.d a6, a1, 0
ld.d a7, a3, -8
/* align up destination address */
andi t1, a0, 7
sub.d t0, zero, t1
addi.d t0, t0, 8
add.d a1, a1, t0
add.d a5, a0, t0
addi.d a4, a3, -64
bgeu a1, a4, .Llt64
/* copy 64 bytes at a time */
.Lloop64:
ld.d t0, a1, 0
ld.d t1, a1, 8
ld.d t2, a1, 16
ld.d t3, a1, 24
ld.d t4, a1, 32
ld.d t5, a1, 40
ld.d t6, a1, 48
ld.d t7, a1, 56
addi.d a1, a1, 64
st.d t0, a5, 0
st.d t1, a5, 8
st.d t2, a5, 16
st.d t3, a5, 24
st.d t4, a5, 32
st.d t5, a5, 40
st.d t6, a5, 48
st.d t7, a5, 56
addi.d a5, a5, 64
bltu a1, a4, .Lloop64
/* copy the remaining bytes */
.Llt64:
addi.d a4, a3, -32
bgeu a1, a4, .Llt32
ld.d t0, a1, 0
ld.d t1, a1, 8
ld.d t2, a1, 16
ld.d t3, a1, 24
addi.d a1, a1, 32
st.d t0, a5, 0
st.d t1, a5, 8
st.d t2, a5, 16
st.d t3, a5, 24
addi.d a5, a5, 32
.Llt32:
addi.d a4, a3, -16
bgeu a1, a4, .Llt16
ld.d t0, a1, 0
ld.d t1, a1, 8
addi.d a1, a1, 16
st.d t0, a5, 0
st.d t1, a5, 8
addi.d a5, a5, 16
.Llt16:
addi.d a4, a3, -8
bgeu a1, a4, .Llt8
ld.d t0, a1, 0
st.d t0, a5, 0
.Llt8:
st.d a6, a0, 0
st.d a7, a2, -8
/* return */
jr ra
SYM_FUNC_END(__memcpy_fast)
_ASM_NOKPROBE(__memcpy_fast)
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