1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Copyright (C) 2013 Regents of the University of California 4 */ 5 6#include <linux/linkage.h> 7#include <asm/asm.h> 8 9/* void *memcpy(void *, const void *, size_t) */ 10ENTRY(memcpy) 11 move t6, a0 /* Preserve return value */ 12 13 /* Defer to byte-oriented copy for small sizes */ 14 sltiu a3, a2, 128 15 bnez a3, 4f 16 /* Use word-oriented copy only if low-order bits match */ 17 andi a3, t6, SZREG-1 18 andi a4, a1, SZREG-1 19 bne a3, a4, 4f 20 21 beqz a3, 2f /* Skip if already aligned */ 22 /* 23 * Round to nearest double word-aligned address 24 * greater than or equal to start address 25 */ 26 andi a3, a1, ~(SZREG-1) 27 addi a3, a3, SZREG 28 /* Handle initial misalignment */ 29 sub a4, a3, a1 301: 31 lb a5, 0(a1) 32 addi a1, a1, 1 33 sb a5, 0(t6) 34 addi t6, t6, 1 35 bltu a1, a3, 1b 36 sub a2, a2, a4 /* Update count */ 37 382: 39 andi a4, a2, ~((16*SZREG)-1) 40 beqz a4, 4f 41 add a3, a1, a4 423: 43 REG_L a4, 0(a1) 44 REG_L a5, SZREG(a1) 45 REG_L a6, 2*SZREG(a1) 46 REG_L a7, 3*SZREG(a1) 47 REG_L t0, 4*SZREG(a1) 48 REG_L t1, 5*SZREG(a1) 49 REG_L t2, 6*SZREG(a1) 50 REG_L t3, 7*SZREG(a1) 51 REG_L t4, 8*SZREG(a1) 52 REG_L t5, 9*SZREG(a1) 53 REG_S a4, 0(t6) 54 REG_S a5, SZREG(t6) 55 REG_S a6, 2*SZREG(t6) 56 REG_S a7, 3*SZREG(t6) 57 REG_S t0, 4*SZREG(t6) 58 REG_S t1, 5*SZREG(t6) 59 REG_S t2, 6*SZREG(t6) 60 REG_S t3, 7*SZREG(t6) 61 REG_S t4, 8*SZREG(t6) 62 REG_S t5, 9*SZREG(t6) 63 REG_L a4, 10*SZREG(a1) 64 REG_L a5, 11*SZREG(a1) 65 REG_L a6, 12*SZREG(a1) 66 REG_L a7, 13*SZREG(a1) 67 REG_L t0, 14*SZREG(a1) 68 REG_L t1, 15*SZREG(a1) 69 addi a1, a1, 16*SZREG 70 REG_S a4, 10*SZREG(t6) 71 REG_S a5, 11*SZREG(t6) 72 REG_S a6, 12*SZREG(t6) 73 REG_S a7, 13*SZREG(t6) 74 REG_S t0, 14*SZREG(t6) 75 REG_S t1, 15*SZREG(t6) 76 addi t6, t6, 16*SZREG 77 bltu a1, a3, 3b 78 andi a2, a2, (16*SZREG)-1 /* Update count */ 79 804: 81 /* Handle trailing misalignment */ 82 beqz a2, 6f 83 add a3, a1, a2 84 85 /* Use word-oriented copy if co-aligned to word boundary */ 86 or a5, a1, t6 87 or a5, a5, a3 88 andi a5, a5, 3 89 bnez a5, 5f 907: 91 lw a4, 0(a1) 92 addi a1, a1, 4 93 sw a4, 0(t6) 94 addi t6, t6, 4 95 bltu a1, a3, 7b 96 97 ret 98 995: 100 lb a4, 0(a1) 101 addi a1, a1, 1 102 sb a4, 0(t6) 103 addi t6, t6, 1 104 bltu a1, a3, 5b 1056: 106 ret 107END(memcpy) 108