diff options
Diffstat (limited to 'arch/csky/abiv2/memcpy.S')
| -rw-r--r-- | arch/csky/abiv2/memcpy.S | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/csky/abiv2/memcpy.S b/arch/csky/abiv2/memcpy.S new file mode 100644 index 000000000..145bf3a93 --- /dev/null +++ b/arch/csky/abiv2/memcpy.S @@ -0,0 +1,104 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include <linux/linkage.h> +#include "sysdep.h" + +ENTRY(__memcpy) +ENTRY(memcpy) + /* Test if len less than 4 bytes. */ + mov r12, r0 + cmplti r2, 4 + bt .L_copy_by_byte + + andi r13, r0, 3 + movi r19, 4 + /* Test if dest is not 4 bytes aligned. */ + bnez r13, .L_dest_not_aligned + +/* Hardware can handle unaligned access directly. */ +.L_dest_aligned: + /* If dest is aligned, then copy. */ + zext r18, r2, 31, 4 + + /* Test if len less than 16 bytes. */ + bez r18, .L_len_less_16bytes + movi r19, 0 + + LABLE_ALIGN +.L_len_larger_16bytes: +#if defined(__CK860__) + ldw r3, (r1, 0) + stw r3, (r0, 0) + ldw r3, (r1, 4) + stw r3, (r0, 4) + ldw r3, (r1, 8) + stw r3, (r0, 8) + ldw r3, (r1, 12) + addi r1, 16 + stw r3, (r0, 12) + addi r0, 16 +#else + ldw r20, (r1, 0) + ldw r21, (r1, 4) + ldw r22, (r1, 8) + ldw r23, (r1, 12) + stw r20, (r0, 0) + stw r21, (r0, 4) + stw r22, (r0, 8) + stw r23, (r0, 12) + PRE_BNEZAD (r18) + addi r1, 16 + addi r0, 16 +#endif + BNEZAD (r18, .L_len_larger_16bytes) + +.L_len_less_16bytes: + zext r18, r2, 3, 2 + bez r18, .L_copy_by_byte +.L_len_less_16bytes_loop: + ldw r3, (r1, 0) + PRE_BNEZAD (r18) + addi r1, 4 + stw r3, (r0, 0) + addi r0, 4 + BNEZAD (r18, .L_len_less_16bytes_loop) + +/* Test if len less than 4 bytes. */ +.L_copy_by_byte: + zext r18, r2, 1, 0 + bez r18, .L_return +.L_copy_by_byte_loop: + ldb r3, (r1, 0) + PRE_BNEZAD (r18) + addi r1, 1 + stb r3, (r0, 0) + addi r0, 1 + BNEZAD (r18, .L_copy_by_byte_loop) + +.L_return: + mov r0, r12 + rts + +/* + * If dest is not aligned, just copying some bytes makes the + * dest align. + */ +.L_dest_not_aligned: + sub r13, r19, r13 + sub r2, r13 + +/* Makes the dest align. */ +.L_dest_not_aligned_loop: + ldb r3, (r1, 0) + PRE_BNEZAD (r13) + addi r1, 1 + stb r3, (r0, 0) + addi r0, 1 + BNEZAD (r13, .L_dest_not_aligned_loop) + cmplti r2, 4 + bt .L_copy_by_byte + + /* Check whether the src is aligned. */ + jbr .L_dest_aligned +ENDPROC(__memcpy) |