1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2020-2021 Loongson Technology Corporation Limited 4 */ 5 6 #include <asm/alternative-asm.h> 7 #include <asm/asm.h> 8 #include <asm/asmmacro.h> 9 #include <asm/cpu.h> 10 #include <asm/export.h> 11 #include <asm/regdef.h> 12 13 .macro fill_to_64 r0 14 bstrins.d \r0, \r0, 15, 8 15 bstrins.d \r0, \r0, 31, 16 16 bstrins.d \r0, \r0, 63, 32 17 .endm 18 19 SYM_FUNC_START_WEAK(memset) 20 SYM_FUNC_START_ALIAS(__memset) 21 /* 22 * Some CPUs support hardware unaligned access 23 */ 24 ALTERNATIVE "b __memset_generic", \ 25 "b __memset_fast", CPU_FEATURE_UAL 26 SYM_FUNC_END(memset) 27 SYM_FUNC_END_ALIAS(__memset) 28 29 EXPORT_SYMBOL(memset) 30 EXPORT_SYMBOL(__memset) 31 32 /* 33 * void *__memset_generic(void *s, int c, size_t n) 34 * 35 * a0: s 36 * a1: c 37 * a2: n 38 */ 39 SYM_FUNC_START(__memset_generic) 40 move a3, a0 41 beqz a2, 2f 42 43 1: st.b a1, a0, 0 44 addi.d a0, a0, 1 45 addi.d a2, a2, -1 46 bgt a2, zero, 1b 47 48 2: move a0, a3 49 jr ra 50 SYM_FUNC_END(__memset_generic) 51 52 /* 53 * void *__memset_fast(void *s, int c, size_t n) 54 * 55 * a0: s 56 * a1: c 57 * a2: n 58 */ 59 SYM_FUNC_START(__memset_fast) 60 /* fill a1 to 64 bits */ 61 fill_to_64 a1 62 63 sltui t0, a2, 9 64 bnez t0, .Lsmall 65 66 add.d a2, a0, a2 67 st.d a1, a0, 0 68 69 /* align up address */ 70 addi.d a3, a0, 8 71 bstrins.d a3, zero, 2, 0 72 73 addi.d a4, a2, -64 74 bgeu a3, a4, .Llt64 75 76 /* set 64 bytes at a time */ 77 .Lloop64: 78 st.d a1, a3, 0 79 st.d a1, a3, 8 80 st.d a1, a3, 16 81 st.d a1, a3, 24 82 st.d a1, a3, 32 83 st.d a1, a3, 40 84 st.d a1, a3, 48 85 st.d a1, a3, 56 86 addi.d a3, a3, 64 87 bltu a3, a4, .Lloop64 88 89 /* set the remaining bytes */ 90 .Llt64: 91 addi.d a4, a2, -32 92 bgeu a3, a4, .Llt32 93 st.d a1, a3, 0 94 st.d a1, a3, 8 95 st.d a1, a3, 16 96 st.d a1, a3, 24 97 addi.d a3, a3, 32 98 99 .Llt32: 100 addi.d a4, a2, -16 101 bgeu a3, a4, .Llt16 102 st.d a1, a3, 0 103 st.d a1, a3, 8 104 addi.d a3, a3, 16 105 106 .Llt16: 107 addi.d a4, a2, -8 108 bgeu a3, a4, .Llt8 109 st.d a1, a3, 0 110 111 .Llt8: 112 st.d a1, a2, -8 113 114 /* return */ 115 jr ra 116 117 .align 4 118 .Lsmall: 119 pcaddi t0, 4 120 slli.d a2, a2, 4 121 add.d t0, t0, a2 122 jr t0 123 124 .align 4 125 0: jr ra 126 127 .align 4 128 1: st.b a1, a0, 0 129 jr ra 130 131 .align 4 132 2: st.h a1, a0, 0 133 jr ra 134 135 .align 4 136 3: st.h a1, a0, 0 137 st.b a1, a0, 2 138 jr ra 139 140 .align 4 141 4: st.w a1, a0, 0 142 jr ra 143 144 .align 4 145 5: st.w a1, a0, 0 146 st.b a1, a0, 4 147 jr ra 148 149 .align 4 150 6: st.w a1, a0, 0 151 st.h a1, a0, 4 152 jr ra 153 154 .align 4 155 7: st.w a1, a0, 0 156 st.w a1, a0, 3 157 jr ra 158 159 .align 4 160 8: st.d a1, a0, 0 161 jr ra 162 SYM_FUNC_END(__memset_fast) 163