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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 | /* SPDX-License-Identifier: GPL-2.0-only */ /* * linux/arch/arm/lib/csumpartialcopygeneric.S * * Copyright (C) 1995-2001 Russell King */ #include <asm/assembler.h> /* * unsigned int * csum_partial_copy_xxx(const char *src, char *dst, int len, int sum, ) * r0 = src, r1 = dst, r2 = len, r3 = sum * Returns : r0 = checksum * * Note that 'tst' and 'teq' preserve the carry flag. */ src .req r0 dst .req r1 len .req r2 sum .req r3 .Lzero: mov r0, sum load_regs /* * Align an unaligned destination pointer. We know that * we have >= 8 bytes here, so we don't need to check * the length. Note that the source pointer hasn't been * aligned yet. */ .Ldst_unaligned: tst dst, #1 beq .Ldst_16bit load1b ip sub len, len, #1 adcs sum, sum, ip, put_byte_1 @ update checksum strb ip, [dst], #1 tst dst, #2 reteq lr @ dst is now 32bit aligned .Ldst_16bit: load2b r8, ip sub len, len, #2 adcs sum, sum, r8, put_byte_0 strb r8, [dst], #1 adcs sum, sum, ip, put_byte_1 strb ip, [dst], #1 ret lr @ dst is now 32bit aligned /* * Handle 0 to 7 bytes, with any alignment of source and * destination pointers. Note that when we get here, C = 0 */ .Lless8: teq len, #0 @ check for zero count beq .Lzero /* we must have at least one byte. */ tst dst, #1 @ dst 16-bit aligned beq .Lless8_aligned /* Align dst */ load1b ip sub len, len, #1 adcs sum, sum, ip, put_byte_1 @ update checksum strb ip, [dst], #1 tst len, #6 beq .Lless8_byteonly 1: load2b r8, ip sub len, len, #2 adcs sum, sum, r8, put_byte_0 strb r8, [dst], #1 adcs sum, sum, ip, put_byte_1 strb ip, [dst], #1 .Lless8_aligned: tst len, #6 bne 1b .Lless8_byteonly: tst len, #1 beq .Ldone load1b r8 adcs sum, sum, r8, put_byte_0 @ update checksum strb r8, [dst], #1 b .Ldone FN_ENTRY save_regs mov sum, #-1 cmp len, #8 @ Ensure that we have at least blo .Lless8 @ 8 bytes to copy. adds sum, sum, #0 @ C = 0 tst dst, #3 @ Test destination alignment blne .Ldst_unaligned @ align destination, return here /* * Ok, the dst pointer is now 32bit aligned, and we know * that we must have more than 4 bytes to copy. Note * that C contains the carry from the dst alignment above. */ tst src, #3 @ Test source alignment bne .Lsrc_not_aligned /* Routine for src & dst aligned */ bics ip, len, #15 beq 2f 1: load4l r4, r5, r6, r7 stmia dst!, {r4, r5, r6, r7} adcs sum, sum, r4 adcs sum, sum, r5 adcs sum, sum, r6 adcs sum, sum, r7 sub ip, ip, #16 teq ip, #0 bne 1b 2: ands ip, len, #12 beq 4f tst ip, #8 beq 3f load2l r4, r5 stmia dst!, {r4, r5} adcs sum, sum, r4 adcs sum, sum, r5 tst ip, #4 beq 4f 3: load1l r4 str r4, [dst], #4 adcs sum, sum, r4 4: ands len, len, #3 beq .Ldone load1l r4 tst len, #2 mov r5, r4, get_byte_0 beq .Lexit adcs sum, sum, r4, lspush #16 strb r5, [dst], #1 mov r5, r4, get_byte_1 strb r5, [dst], #1 mov r5, r4, get_byte_2 .Lexit: tst len, #1 strbne r5, [dst], #1 andne r5, r5, #255 adcsne sum, sum, r5, put_byte_0 /* * If the dst pointer was not 16-bit aligned, we * need to rotate the checksum here to get around * the inefficient byte manipulations in the * architecture independent code. */ .Ldone: adc r0, sum, #0 ldr sum, [sp, #0] @ dst tst sum, #1 movne r0, r0, ror #8 load_regs .Lsrc_not_aligned: adc sum, sum, #0 @ include C from dst alignment and ip, src, #3 bic src, src, #3 load1l r5 cmp ip, #2 beq .Lsrc2_aligned bhi .Lsrc3_aligned mov r4, r5, lspull #8 @ C = 0 bics ip, len, #15 beq 2f 1: load4l r5, r6, r7, r8 orr r4, r4, r5, lspush #24 mov r5, r5, lspull #8 orr r5, r5, r6, lspush #24 mov r6, r6, lspull #8 orr r6, r6, r7, lspush #24 mov r7, r7, lspull #8 orr r7, r7, r8, lspush #24 stmia dst!, {r4, r5, r6, r7} adcs sum, sum, r4 adcs sum, sum, r5 adcs sum, sum, r6 adcs sum, sum, r7 mov r4, r8, lspull #8 sub ip, ip, #16 teq ip, #0 bne 1b 2: ands ip, len, #12 beq 4f tst ip, #8 beq 3f load2l r5, r6 orr r4, r4, r5, lspush #24 mov r5, r5, lspull #8 orr r5, r5, r6, lspush #24 stmia dst!, {r4, r5} adcs sum, sum, r4 adcs sum, sum, r5 mov r4, r6, lspull #8 tst ip, #4 beq 4f 3: load1l r5 orr r4, r4, r5, lspush #24 str r4, [dst], #4 adcs sum, sum, r4 mov r4, r5, lspull #8 4: ands len, len, #3 beq .Ldone mov r5, r4, get_byte_0 tst len, #2 beq .Lexit adcs sum, sum, r4, lspush #16 strb r5, [dst], #1 mov r5, r4, get_byte_1 strb r5, [dst], #1 mov r5, r4, get_byte_2 b .Lexit .Lsrc2_aligned: mov r4, r5, lspull #16 adds sum, sum, #0 bics ip, len, #15 beq 2f 1: load4l r5, r6, r7, r8 orr r4, r4, r5, lspush #16 mov r5, r5, lspull #16 orr r5, r5, r6, lspush #16 mov r6, r6, lspull #16 orr r6, r6, r7, lspush #16 mov r7, r7, lspull #16 orr r7, r7, r8, lspush #16 stmia dst!, {r4, r5, r6, r7} adcs sum, sum, r4 adcs sum, sum, r5 adcs sum, sum, r6 adcs sum, sum, r7 mov r4, r8, lspull #16 sub ip, ip, #16 teq ip, #0 bne 1b 2: ands ip, len, #12 beq 4f tst ip, #8 beq 3f load2l r5, r6 orr r4, r4, r5, lspush #16 mov r5, r5, lspull #16 orr r5, r5, r6, lspush #16 stmia dst!, {r4, r5} adcs sum, sum, r4 adcs sum, sum, r5 mov r4, r6, lspull #16 tst ip, #4 beq 4f 3: load1l r5 orr r4, r4, r5, lspush #16 str r4, [dst], #4 adcs sum, sum, r4 mov r4, r5, lspull #16 4: ands len, len, #3 beq .Ldone mov r5, r4, get_byte_0 tst len, #2 beq .Lexit adcs sum, sum, r4 strb r5, [dst], #1 mov r5, r4, get_byte_1 strb r5, [dst], #1 tst len, #1 beq .Ldone load1b r5 b .Lexit .Lsrc3_aligned: mov r4, r5, lspull #24 adds sum, sum, #0 bics ip, len, #15 beq 2f 1: load4l r5, r6, r7, r8 orr r4, r4, r5, lspush #8 mov r5, r5, lspull #24 orr r5, r5, r6, lspush #8 mov r6, r6, lspull #24 orr r6, r6, r7, lspush #8 mov r7, r7, lspull #24 orr r7, r7, r8, lspush #8 stmia dst!, {r4, r5, r6, r7} adcs sum, sum, r4 adcs sum, sum, r5 adcs sum, sum, r6 adcs sum, sum, r7 mov r4, r8, lspull #24 sub ip, ip, #16 teq ip, #0 bne 1b 2: ands ip, len, #12 beq 4f tst ip, #8 beq 3f load2l r5, r6 orr r4, r4, r5, lspush #8 mov r5, r5, lspull #24 orr r5, r5, r6, lspush #8 stmia dst!, {r4, r5} adcs sum, sum, r4 adcs sum, sum, r5 mov r4, r6, lspull #24 tst ip, #4 beq 4f 3: load1l r5 orr r4, r4, r5, lspush #8 str r4, [dst], #4 adcs sum, sum, r4 mov r4, r5, lspull #24 4: ands len, len, #3 beq .Ldone mov r5, r4, get_byte_0 tst len, #2 beq .Lexit strb r5, [dst], #1 adcs sum, sum, r4 load1l r4 mov r5, r4, get_byte_0 strb r5, [dst], #1 adcs sum, sum, r4, lspush #24 mov r5, r4, get_byte_1 b .Lexit FN_EXIT |