diff options
Diffstat (limited to 'arch/loongarch/lib/memcpy.S')
| -rw-r--r-- | arch/loongarch/lib/memcpy.S | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/arch/loongarch/lib/memcpy.S b/arch/loongarch/lib/memcpy.S new file mode 100644 index 000000000..fa1148878 --- /dev/null +++ b/arch/loongarch/lib/memcpy.S @@ -0,0 +1,199 @@ +/* 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> + +.section .noinstr.text, "ax" + +SYM_FUNC_START(memcpy) + /* + * Some CPUs support hardware unaligned access + */ + ALTERNATIVE "b __memcpy_generic", \ + "b __memcpy_fast", CPU_FEATURE_UAL +SYM_FUNC_END(memcpy) +SYM_FUNC_ALIAS(__memcpy, memcpy) + +EXPORT_SYMBOL(memcpy) +EXPORT_SYMBOL(__memcpy) + +_ASM_NOKPROBE(memcpy) +_ASM_NOKPROBE(__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) |