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/asm-extable.h> 10 #include <asm/cpu.h> 11 #include <asm/export.h> 12 #include <asm/regdef.h> 13 14 SYM_FUNC_START(__copy_user) 15 /* 16 * Some CPUs support hardware unaligned access 17 */ 18 ALTERNATIVE "b __copy_user_generic", \ 19 "b __copy_user_fast", CPU_FEATURE_UAL 20 SYM_FUNC_END(__copy_user) 21 22 EXPORT_SYMBOL(__copy_user) 23 24 /* 25 * unsigned long __copy_user_generic(void *to, const void *from, size_t n) 26 * 27 * a0: to 28 * a1: from 29 * a2: n 30 */ 31 SYM_FUNC_START(__copy_user_generic) 32 beqz a2, 3f 33 34 1: ld.b t0, a1, 0 35 2: st.b t0, a0, 0 36 addi.d a0, a0, 1 37 addi.d a1, a1, 1 38 addi.d a2, a2, -1 39 bgt a2, zero, 1b 40 41 3: move a0, a2 42 jr ra 43 44 _asm_extable 1b, 3b 45 _asm_extable 2b, 3b 46 SYM_FUNC_END(__copy_user_generic) 47 48 /* 49 * unsigned long __copy_user_fast(void *to, const void *from, unsigned long n) 50 * 51 * a0: to 52 * a1: from 53 * a2: n 54 */ 55 SYM_FUNC_START(__copy_user_fast) 56 sltui t0, a2, 9 57 bnez t0, .Lsmall 58 59 0: ld.d t0, a1, 0 60 1: st.d t0, a0, 0 61 add.d a3, a1, a2 62 add.d a2, a0, a2 63 64 /* align up destination address */ 65 andi t1, a0, 7 66 sub.d t0, zero, t1 67 addi.d t0, t0, 8 68 add.d a1, a1, t0 69 add.d a0, a0, t0 70 71 addi.d a4, a3, -64 72 bgeu a1, a4, .Llt64 73 74 /* copy 64 bytes at a time */ 75 .Lloop64: 76 2: ld.d t0, a1, 0 77 3: ld.d t1, a1, 8 78 4: ld.d t2, a1, 16 79 5: ld.d t3, a1, 24 80 6: ld.d t4, a1, 32 81 7: ld.d t5, a1, 40 82 8: ld.d t6, a1, 48 83 9: ld.d t7, a1, 56 84 10: st.d t0, a0, 0 85 11: st.d t1, a0, 8 86 12: st.d t2, a0, 16 87 13: st.d t3, a0, 24 88 14: st.d t4, a0, 32 89 15: st.d t5, a0, 40 90 16: st.d t6, a0, 48 91 17: st.d t7, a0, 56 92 addi.d a1, a1, 64 93 addi.d a0, a0, 64 94 bltu a1, a4, .Lloop64 95 96 /* copy the remaining bytes */ 97 .Llt64: 98 addi.d a4, a3, -32 99 bgeu a1, a4, .Llt32 100 18: ld.d t0, a1, 0 101 19: ld.d t1, a1, 8 102 20: ld.d t2, a1, 16 103 21: ld.d t3, a1, 24 104 22: st.d t0, a0, 0 105 23: st.d t1, a0, 8 106 24: st.d t2, a0, 16 107 25: st.d t3, a0, 24 108 addi.d a1, a1, 32 109 addi.d a0, a0, 32 110 111 .Llt32: 112 addi.d a4, a3, -16 113 bgeu a1, a4, .Llt16 114 26: ld.d t0, a1, 0 115 27: ld.d t1, a1, 8 116 28: st.d t0, a0, 0 117 29: st.d t1, a0, 8 118 addi.d a1, a1, 16 119 addi.d a0, a0, 16 120 121 .Llt16: 122 addi.d a4, a3, -8 123 bgeu a1, a4, .Llt8 124 30: ld.d t0, a1, 0 125 31: st.d t0, a0, 0 126 addi.d a1, a1, 8 127 addi.d a0, a0, 8 128 129 .Llt8: 130 32: ld.d t0, a3, -8 131 33: st.d t0, a2, -8 132 133 /* return */ 134 move a0, zero 135 jr ra 136 137 .align 5 138 .Lsmall: 139 pcaddi t0, 8 140 slli.d a3, a2, 5 141 add.d t0, t0, a3 142 jr t0 143 144 .align 5 145 move a0, zero 146 jr ra 147 148 .align 5 149 34: ld.b t0, a1, 0 150 35: st.b t0, a0, 0 151 move a0, zero 152 jr ra 153 154 .align 5 155 36: ld.h t0, a1, 0 156 37: st.h t0, a0, 0 157 move a0, zero 158 jr ra 159 160 .align 5 161 38: ld.h t0, a1, 0 162 39: ld.b t1, a1, 2 163 40: st.h t0, a0, 0 164 41: st.b t1, a0, 2 165 move a0, zero 166 jr ra 167 168 .align 5 169 42: ld.w t0, a1, 0 170 43: st.w t0, a0, 0 171 move a0, zero 172 jr ra 173 174 .align 5 175 44: ld.w t0, a1, 0 176 45: ld.b t1, a1, 4 177 46: st.w t0, a0, 0 178 47: st.b t1, a0, 4 179 move a0, zero 180 jr ra 181 182 .align 5 183 48: ld.w t0, a1, 0 184 49: ld.h t1, a1, 4 185 50: st.w t0, a0, 0 186 51: st.h t1, a0, 4 187 move a0, zero 188 jr ra 189 190 .align 5 191 52: ld.w t0, a1, 0 192 53: ld.w t1, a1, 3 193 54: st.w t0, a0, 0 194 55: st.w t1, a0, 3 195 move a0, zero 196 jr ra 197 198 .align 5 199 56: ld.d t0, a1, 0 200 57: st.d t0, a0, 0 201 move a0, zero 202 jr ra 203 204 /* fixup and ex_table */ 205 .Llarge_fixup: 206 sub.d a2, a2, a0 207 208 .Lsmall_fixup: 209 58: ld.b t0, a1, 0 210 59: st.b t0, a0, 0 211 addi.d a0, a0, 1 212 addi.d a1, a1, 1 213 addi.d a2, a2, -1 214 bgt a2, zero, 58b 215 216 .Lexit: 217 move a0, a2 218 jr ra 219 220 _asm_extable 0b, .Lsmall_fixup 221 _asm_extable 1b, .Lsmall_fixup 222 _asm_extable 2b, .Llarge_fixup 223 _asm_extable 3b, .Llarge_fixup 224 _asm_extable 4b, .Llarge_fixup 225 _asm_extable 5b, .Llarge_fixup 226 _asm_extable 6b, .Llarge_fixup 227 _asm_extable 7b, .Llarge_fixup 228 _asm_extable 8b, .Llarge_fixup 229 _asm_extable 9b, .Llarge_fixup 230 _asm_extable 10b, .Llarge_fixup 231 _asm_extable 11b, .Llarge_fixup 232 _asm_extable 12b, .Llarge_fixup 233 _asm_extable 13b, .Llarge_fixup 234 _asm_extable 14b, .Llarge_fixup 235 _asm_extable 15b, .Llarge_fixup 236 _asm_extable 16b, .Llarge_fixup 237 _asm_extable 17b, .Llarge_fixup 238 _asm_extable 18b, .Llarge_fixup 239 _asm_extable 19b, .Llarge_fixup 240 _asm_extable 20b, .Llarge_fixup 241 _asm_extable 21b, .Llarge_fixup 242 _asm_extable 22b, .Llarge_fixup 243 _asm_extable 23b, .Llarge_fixup 244 _asm_extable 24b, .Llarge_fixup 245 _asm_extable 25b, .Llarge_fixup 246 _asm_extable 26b, .Llarge_fixup 247 _asm_extable 27b, .Llarge_fixup 248 _asm_extable 28b, .Llarge_fixup 249 _asm_extable 29b, .Llarge_fixup 250 _asm_extable 30b, .Llarge_fixup 251 _asm_extable 31b, .Llarge_fixup 252 _asm_extable 32b, .Llarge_fixup 253 _asm_extable 33b, .Llarge_fixup 254 _asm_extable 34b, .Lexit 255 _asm_extable 35b, .Lexit 256 _asm_extable 36b, .Lsmall_fixup 257 _asm_extable 37b, .Lsmall_fixup 258 _asm_extable 38b, .Lsmall_fixup 259 _asm_extable 39b, .Lsmall_fixup 260 _asm_extable 40b, .Lsmall_fixup 261 _asm_extable 41b, .Lsmall_fixup 262 _asm_extable 42b, .Lsmall_fixup 263 _asm_extable 43b, .Lsmall_fixup 264 _asm_extable 44b, .Lsmall_fixup 265 _asm_extable 45b, .Lsmall_fixup 266 _asm_extable 46b, .Lsmall_fixup 267 _asm_extable 47b, .Lsmall_fixup 268 _asm_extable 48b, .Lsmall_fixup 269 _asm_extable 49b, .Lsmall_fixup 270 _asm_extable 50b, .Lsmall_fixup 271 _asm_extable 51b, .Lsmall_fixup 272 _asm_extable 52b, .Lsmall_fixup 273 _asm_extable 53b, .Lsmall_fixup 274 _asm_extable 54b, .Lsmall_fixup 275 _asm_extable 55b, .Lsmall_fixup 276 _asm_extable 56b, .Lsmall_fixup 277 _asm_extable 57b, .Lsmall_fixup 278 _asm_extable 58b, .Lexit 279 _asm_extable 59b, .Lexit 280 SYM_FUNC_END(__copy_user_fast) 281