diff options
Diffstat (limited to 'arch/loongarch/lib/memcpy.S')
-rw-r--r-- | arch/loongarch/lib/memcpy.S | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/loongarch/lib/memcpy.S b/arch/loongarch/lib/memcpy.S new file mode 100644 index 000000000000..7c07d595ee89 --- /dev/null +++ b/arch/loongarch/lib/memcpy.S @@ -0,0 +1,95 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include <asm/alternative-asm.h> +#include <asm/asm.h> +#include <asm/asmmacro.h> +#include <asm/cpu.h> +#include <asm/export.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) + +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) + +/* + * void *__memcpy_fast(void *dst, const void *src, size_t n) + * + * a0: dst + * a1: src + * a2: n + */ +SYM_FUNC_START(__memcpy_fast) + move a3, a0 + beqz a2, 3f + + ori a4, zero, 64 + blt a2, a4, 2f + + /* copy 64 bytes at a time */ +1: 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 + st.d t0, a0, 0 + st.d t1, a0, 8 + st.d t2, a0, 16 + st.d t3, a0, 24 + st.d t4, a0, 32 + st.d t5, a0, 40 + st.d t6, a0, 48 + st.d t7, a0, 56 + + addi.d a0, a0, 64 + addi.d a1, a1, 64 + addi.d a2, a2, -64 + bge a2, a4, 1b + + beqz a2, 3f + + /* copy the remaining bytes */ +2: 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, 2b + + /* return */ +3: move a0, a3 + jr ra +SYM_FUNC_END(__memcpy_fast) |