trap_subr.S revision 1.28
1 /* $NetBSD: trap_subr.S,v 1.28 2020/03/01 23:23:36 rin Exp $ */ 2 3 /* 4 * Copyright 2001 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /* 39 * Copyright (C) 1995, 1996 Wolfgang Solfrank. 40 * Copyright (C) 1995, 1996 TooLs GmbH. 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by TooLs GmbH. 54 * 4. The name of TooLs GmbH may not be used to endorse or promote products 55 * derived from this software without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 60 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 61 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 62 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 63 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 64 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 65 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 66 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * NOTICE: This is not a standalone file. to use it, #include it in 71 * your port's locore.S, like so: 72 * 73 * #include <powerpc/ibm4xx/trap_subr.S> 74 */ 75 76 /* 77 * XXX Interrupt and spill stacks need to be per-CPU. 78 */ 79 80 #define GET_PCB(rX) \ 81 GET_CPUINFO(rX); \ 82 lwz rX,CI_CURPCB(rX) 83 84 #define STANDARD_PROLOG(savearea) \ 85 mtsprg1 %r1; /* save SP */ \ 86 GET_CPUINFO(%r1); \ 87 stmw %r28,(savearea+CPUSAVE_R28)(%r1); /* free r28-r31 */ \ 88 mflr %r28; /* save LR */ \ 89 mfcr %r29; /* save CR */ \ 90 mfsrr0 %r30; \ 91 mfsrr1 %r31; /* Test whether we already had PR set */ \ 92 stmw %r30,(savearea+CPUSAVE_SRR0)(%r1); /* save srr0/srr1 */ \ 93 mfsprg1 %r1; /* restore SP */ \ 94 mtcr %r31; \ 95 bf MSR_PR,1f; /* branch if MSR[PR] is clear */ \ 96 GET_PCB(%r1); \ 97 addi %r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \ 98 1: 99 100 #define ACCESS_PROLOG(savearea) \ 101 mtsprg1 %r1; /* save SP temporalily */ \ 102 GET_CPUINFO(%r1); \ 103 stmw %r28,(savearea+CPUSAVE_R28)(%r1); /* free r28-r31 */ \ 104 mflr %r28; /* save LR */ \ 105 mfcr %r29; /* save CR */ \ 106 mfdear %r30; \ 107 mfesr %r31; \ 108 stmw %r30,(savearea+CPUSAVE_DEAR)(%r1); /* save esr/dear */ \ 109 mfsrr0 %r30; \ 110 mfsrr1 %r31; /* Test whether we already had PR set */ \ 111 stmw %r30,(savearea+CPUSAVE_SRR0)(%r1); /* save srr0/srr1 */ \ 112 mfsprg1 %r1; /* restore SP */ \ 113 mtcr %r31; \ 114 bf MSR_PR,1f; /* branch if MSR[PR] is clear */ \ 115 GET_PCB(%r1); \ 116 addi %r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \ 117 1: 118 119 #define CRITICAL_PROLOG(savearea) \ 120 mtsprg1 %r1; /* save SP */ \ 121 GET_CPUINFO(%r1); \ 122 stmw %r28,(savearea+CPUSAVE_R28)(%r1); /* free r28-r31 */ \ 123 mflr %r28; /* save LR */ \ 124 mfcr %r29; /* save CR */ \ 125 mfsrr2 %r30; /* Fake a standard trap */ \ 126 mfsrr3 %r31; /* Test whether we already had PR set */ \ 127 stmw %r30,(savearea+CPUSAVE_SRR0)(%r1); /* save srr0/srr1 */ \ 128 mfsprg1 %r1; /* restore SP */ \ 129 mtcr %r31; \ 130 bf MSR_PR,1f; /* branch if MSR[PR] is clear */ \ 131 GET_PCB(%r1); \ 132 addi %r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \ 133 1: 134 135 136 /* Standard handler saves r1,r28-31,LR,CR, sets up the stack and calls s_trap */ 137 #define STANDARD_EXC_HANDLER(name)\ 138 .globl _C_LABEL(name ## trap),_C_LABEL(name ## size) ; \ 139 _C_LABEL(name ## trap): \ 140 STANDARD_PROLOG(CI_TEMPSAVE); \ 141 bla s_trap; \ 142 _C_LABEL(name ## size) = .-_C_LABEL(name ## trap) 143 144 /* Access exceptions also need DEAR and ESR saved */ 145 #define ACCESS_EXC_HANDLER(name)\ 146 .globl _C_LABEL(name ## trap),_C_LABEL(name ## size) ; \ 147 _C_LABEL(name ## trap): \ 148 ACCESS_PROLOG(CI_TEMPSAVE); \ 149 bla s_trap; \ 150 _C_LABEL(name ## size) = .-_C_LABEL(name ## trap) 151 152 /* Maybe this should call ddb.... */ 153 #define CRITICAL_EXC_HANDLER(name)\ 154 .globl _C_LABEL(name ## trap),_C_LABEL(name ## size) ; \ 155 _C_LABEL(name ## trap): \ 156 CRITICAL_PROLOG(CI_TEMPSAVE); \ 157 bla s_trap; \ 158 _C_LABEL(name ## size) = .-_C_LABEL(name ## trap) 159 160 #define INTR_PROLOG(tempsave) \ 161 mtsprg1 %r1; /* save SP */ \ 162 GET_CPUINFO(%r1); \ 163 stmw %r28,(tempsave+CPUSAVE_R28)(%r1); /* free r28-r31 */ \ 164 mflr %r28; /* save LR */ \ 165 mfcr %r29; /* save CR */ \ 166 mfxer %r30; /* save XER */ \ 167 mfsrr1 %r31; \ 168 mtcr %r31; \ 169 mfsprg1 %r1; /* restore SP */ \ 170 bf MSR_PR,1f; /* branch if PSL_PR is false */ \ 171 GET_PCB(%r1); \ 172 addi %r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \ 173 1: 174 175 .text 176 STANDARD_EXC_HANDLER(default) 177 ACCESS_EXC_HANDLER(access) 178 CRITICAL_EXC_HANDLER(critical) 179 180 /* 181 * This one for the external interrupt handler. 182 */ 183 .globl _C_LABEL(extint),_C_LABEL(extsize) 184 _C_LABEL(extint): 185 INTR_PROLOG(CI_TEMPSAVE) 186 ba extintr 187 _C_LABEL(extsize) = .-_C_LABEL(extint) 188 189 190 #if defined(DDB) || defined(KGDB) 191 /* 192 * In case of DDB we want a separate trap catcher for it 193 */ 194 .globl _C_LABEL(ddblow),_C_LABEL(ddbsize) 195 _C_LABEL(ddblow): 196 ACCESS_PROLOG(CI_DDBSAVE) 197 bla ddbtrap 198 _C_LABEL(ddbsize) = .-_C_LABEL(ddblow) 199 #endif /* DDB || KGDB */ 200 201 #ifdef DEBUG 202 #define TRAP_IF_ZERO(r) tweqi r,0 203 #else 204 #define TRAP_IF_ZERO(r) 205 #endif 206 207 #define ENABLE_TRANSLATION(pidreg,tmpreg) \ 208 mfpid pidreg; \ 209 li tmpreg,KERNEL_PID; \ 210 mtpid tmpreg; \ 211 mfmsr tmpreg; \ 212 ori tmpreg,tmpreg,(PSL_DR|PSL_IR)@l; \ 213 mtmsr tmpreg; \ 214 isync 215 216 /* 217 * FRAME_SETUP assumes: 218 * SPRG1 SP (r1) 219 * savearea r28-r31,DEAR,ESR,SRR0,SRR1 220 * (DEAR & ESR only for access traps) 221 * %r28 LR 222 * %r29 CR 223 * %r1 kernel stack 224 * LR trap type 225 */ 226 #define FRAME_SETUP(savearea) \ 227 /* Have to enable translation to allow access of kernel stack: */ \ 228 ENABLE_TRANSLATION(%r30,%r31); \ 229 mfsprg1 %r31; \ 230 stwu %r31,-FRAMELEN(%r1); \ 231 stw %r30,FRAME_PID(%r1); \ 232 stw %r0,FRAME_R0(%r1); \ 233 stw %r31,FRAME_R1(%r1); \ 234 stw %r2,FRAME_R2(%r1); \ 235 GET_CPUINFO(%r2); \ 236 stw %r28,FRAME_LR(%r1); \ 237 stw %r29,FRAME_CR(%r1); \ 238 lmw %r28,(savearea+CPUSAVE_R28)(%r2); \ 239 stmw %r3,FRAME_R3(%r1); \ 240 lmw %r28,(savearea+CPUSAVE_DEAR)(%r2); \ 241 lwz %r13,CI_CURLWP(%r2); \ 242 mfxer %r3; \ 243 mfctr %r4; \ 244 mflr %r5; \ 245 andi. %r5,%r5,0xff00; \ 246 stw %r3,FRAME_XER(%r1); \ 247 stw %r4,FRAME_CTR(%r1); \ 248 stw %r5,FRAME_EXC(%r1); \ 249 stw %r28,FRAME_DEAR(%r1); \ 250 stw %r29,FRAME_ESR(%r1); \ 251 stw %r30,FRAME_SRR0(%r1); \ 252 stw %r31,FRAME_SRR1(%r1) 253 254 #define FRAME_SAVE_CALLEE \ 255 stmw %r14,FRAME_R14(%r1) 256 257 #define FRAME_RESTORE \ 258 lwz %r6,FRAME_LR(%r1); \ 259 lwz %r7,FRAME_CR(%r1); \ 260 lwz %r8,FRAME_XER(%r1); \ 261 lwz %r9,FRAME_CTR(%r1); \ 262 lwz %r10,FRAME_SRR0(%r1); \ 263 lwz %r11,FRAME_SRR1(%r1); \ 264 mtlr %r6; \ 265 mtcr %r7; \ 266 mtxer %r8; \ 267 mtctr %r9; \ 268 mtsrr0 %r10; \ 269 mtsrr1 %r11; \ 270 lwz %r13,FRAME_R13(%r1); \ 271 lwz %r12,FRAME_R12(%r1); \ 272 lwz %r11,FRAME_R11(%r1); \ 273 lwz %r10,FRAME_R10(%r1); \ 274 lwz %r9,FRAME_R9(%r1); \ 275 lwz %r8,FRAME_R8(%r1); \ 276 lwz %r7,FRAME_R7(%r1); \ 277 lwz %r6,FRAME_R6(%r1); \ 278 lwz %r5,FRAME_R5(%r1); \ 279 lwz %r4,FRAME_R4(%r1); \ 280 lwz %r3,FRAME_R3(%r1); \ 281 lwz %r2,FRAME_R2(%r1); \ 282 lwz %r0,FRAME_R1(%r1); \ 283 mtsprg1 %r0; \ 284 lwz %r0,FRAME_R0(%r1) 285 286 /* 287 * Now the common trap catching code. 288 */ 289 s_trap: 290 FRAME_SETUP(CI_TEMPSAVE) 291 /* R31 = SRR1 */ 292 /* Now we can recover interrupts again: */ 293 trapagain: 294 wrtee %r31 /* reenable interrupts */ 295 /* Call C trap code: */ 296 addi %r3,%r1,FRAME_TF 297 bl _C_LABEL(trap) 298 .globl _C_LABEL(trapexit) 299 _C_LABEL(trapexit): 300 /* Disable interrupts: */ 301 wrteei 0 302 303 /* Test AST pending: */ 304 mtcr %r31 305 bf MSR_PR,trapleave_to_kernel /* branch if MSR[PR] is false */ 306 307 lwz %r4,L_MD_ASTPENDING(%r13) 308 andi. %r4,%r4,1 309 beq trapleave_to_user 310 311 li %r6,EXC_AST 312 stw %r6,FRAME_EXC(%r1) 313 b trapagain 314 315 trapleave_to_kernel: 316 lmw %r14, FRAME_R14(%r1) /* restore callee registers */ 317 318 intrleave_to_kernel: 319 FRAME_RESTORE /* old SP is now in sprg1 */ 320 321 mtsprg2 %r30 322 mtsprg3 %r31 323 mfmsr %r30 324 li %r31,(PSL_DR|PSL_IR)@l 325 andc %r30,%r30,%r31 326 lwz %r31,FRAME_PID(%r1) 327 TRAP_IF_ZERO(%r31) 328 /* 329 * Now that we are done with the trapframe, we can load the original SP 330 */ 331 mfsprg1 %r1 332 mtmsr %r30 /* disable translation */ 333 isync 334 mtpid %r31 335 mfsprg3 %r31 336 mfsprg2 %r30 337 IBM405_ERRATA77_SYNC 338 rfi 339 ba . /* Protect against prefetch */ 340 341 trapleave_to_user: 342 lmw %r14, FRAME_R14(%r1) /* restore callee registers */ 343 344 intrleave_to_user: 345 /* Now restore regs: */ 346 lwz %r3,FRAME_PID(%r1) 347 lwz %r4,FRAME_SRR1(%r1) 348 bl _C_LABEL(ctx_setup) 349 TRAP_IF_ZERO(%r3) 350 stw %r3,FRAME_PID(%r1) 351 352 FRAME_RESTORE /* old SP is now in sprg1 */ 353 354 /* 355 * We are returning to userspace so we need to switch PIDs. 356 * Since the kernel executes out of what would be userspace, 357 * we need to turn off translation before we set the PID. 358 * 359 * Alterantively, we could map a kernel page at 0xfffff000 360 * that had the mtpid code in it and branch to it and avoid 361 * all this. (ba foo; foo: mtpid %r31; mfsprg3 %r31; rfi;) 362 */ 363 mtsprg2 %r30 364 mtsprg3 %r31 365 mfmsr %r30 366 li %r31,(PSL_DR|PSL_IR)@l 367 andc %r30,%r30,%r31 368 lwz %r31,FRAME_PID(%r1) 369 TRAP_IF_ZERO(%r31) 370 /* 371 * Now that we are done with the trapframe, we can load the original SP 372 */ 373 mfsprg1 %r1 374 mtmsr %r30 /* disable translation */ 375 isync 376 mtpid %r31 377 mfsprg3 %r31 378 mfsprg2 %r30 379 IBM405_ERRATA77_SYNC 380 rfi 381 ba . /* Protect against prefetch */ 382 383 384 .globl _C_LABEL(sctrap),_C_LABEL(scsize),_C_LABEL(sctrapexit) 385 _C_LABEL(sctrap): 386 STANDARD_PROLOG(CI_TEMPSAVE) 387 bla s_sctrap 388 _C_LABEL(scsize) = .-_C_LABEL(sctrap) 389 390 s_sctrap: 391 FRAME_SETUP(CI_TEMPSAVE) 392 /* Now we can recover interrupts again: */ 393 wrteei 1 /* Enable interrupts */ 394 /* Call the appropriate syscall handler: */ 395 addi %r3,%r1,FRAME_TF 396 lwz %r4,L_PROC(%r13) 397 lwz %r4,P_MD_SYSCALL(%r4) 398 mtctr %r4 399 bctrl 400 _C_LABEL(sctrapexit): 401 b trapexit 402 403 /* 404 * External interrupt second level handler 405 */ 406 407 #define INTR_SAVE(tempsave) \ 408 /* Save non-volatile registers: */ \ 409 stwu %r1,-FRAMELEN(%r1); /* temporarily */ \ 410 stw %r0,FRAME_R0(%r1); \ 411 mfsprg1 %r0; /* get original SP */ \ 412 stw %r0,FRAME_R1(%r1); /* and store it */ \ 413 stw %r2,FRAME_R2(%r1); \ 414 stw %r3,FRAME_R3(%r1); \ 415 stw %r4,FRAME_R4(%r1); \ 416 stw %r5,FRAME_R5(%r1); \ 417 stw %r6,FRAME_R6(%r1); \ 418 stw %r7,FRAME_R7(%r1); \ 419 stw %r8,FRAME_R8(%r1); \ 420 stw %r9,FRAME_R9(%r1); \ 421 stw %r10,FRAME_R10(%r1); \ 422 stw %r11,FRAME_R11(%r1); \ 423 stw %r12,FRAME_R12(%r1); \ 424 stw %r13,FRAME_R13(%r1); \ 425 mfctr %r31; \ 426 stmw %r28,FRAME_LR(%r1); /* save LR, CR, XER, CTR */ \ 427 GET_CPUINFO(%r5); \ 428 lmw %r28,(tempsave+CPUSAVE_R28)(%r5); /* restore r28-r31 */ \ 429 lwz %r13,CI_CURLWP(%r5); \ 430 lwz %r5,CI_IDEPTH(%r5); \ 431 mfsrr0 %r4; \ 432 mfsrr1 %r3; \ 433 stw %r5,FRAME_IDEPTH(%r1); \ 434 stw %r4,FRAME_SRR0(%r1); \ 435 stw %r3,FRAME_SRR1(%r1); \ 436 /* interrupts are recoverable here, and enable translation */ \ 437 ENABLE_TRANSLATION(%r0,%r5); \ 438 stw %r0,FRAME_PID(%r1); 439 440 .globl _C_LABEL(extint_call) 441 extintr: 442 INTR_SAVE(CI_TEMPSAVE) 443 _C_LABEL(extint_call): 444 bl _C_LABEL(extint_call) /* to be filled in later */ 445 446 intr_exit: 447 /* Disable interrupts */ 448 wrteei 0 449 isync 450 451 lwz %r4,FRAME_SRR1(%r1) 452 /* Returning to user mode? */ 453 mtcr %r4 /* saved SRR1 */ 454 bf MSR_PR,intrleave_to_kernel /* branch if MSR[PR] is false */ 455 456 lwz %r4,L_MD_ASTPENDING(%r13)/* Test AST pending */ 457 andi. %r4,%r4,1 458 beq intrleave_to_user 459 460 FRAME_SAVE_CALLEE /* save rest of callee registers */ 461 li %r6,EXC_AST 462 stw %r6,FRAME_EXC(%r1) 463 lwz %r31,FRAME_SRR1(%r1) /* move SRR1 to R31 */ 464 b trapagain 465 466 /* 467 * PIT interrupt handler. 468 */ 469 .align 5 470 _C_LABEL(pitint): 471 INTR_PROLOG(CI_TEMPSAVE) 472 INTR_SAVE(CI_TEMPSAVE) 473 addi %r3,%r1,FRAME_CF /* clock frame */ 474 bl _C_LABEL(decr_intr) 475 b intr_exit 476 477 /* 478 * FIT interrupt handler. 479 */ 480 .align 5 481 _C_LABEL(fitint): 482 INTR_PROLOG(CI_TEMPSAVE) 483 INTR_SAVE(CI_TEMPSAVE) 484 addi %r3,%r1,FRAME_CF /* clock frame */ 485 bl _C_LABEL(stat_intr) 486 b intr_exit 487 488 #if defined(DDB) || defined(KGDB) 489 /* 490 * Deliberate entry to ddbtrap 491 */ 492 .globl _C_LABEL(ddb_trap) 493 _C_LABEL(ddb_trap): 494 mtsprg1 %r1 495 GET_CPUINFO(%r4) 496 mfmsr %r3 497 stw %r3,(CI_DDBSAVE+CPUSAVE_SRR1)(%r4) 498 wrteei 0 /* disable interrupts */ 499 isync 500 stmw %r28,CI_DDBSAVE(%r4) 501 mflr %r28 502 stw %r28,(CI_DDBSAVE+CPUSAVE_SRR0)(%r4) 503 li %r29,EXC_BPT 504 mtlr %r29 505 mfcr %r29 506 507 /* 508 * Now the ddb/kgdb trap catching code. 509 */ 510 ddbtrap: 511 FRAME_SETUP(CI_DDBSAVE) 512 /* Call C trap code: */ 513 addi %r3,%r1,FRAME_TF 514 bl _C_LABEL(ddb_trap_glue) 515 or. %r3,%r3,%r3 516 beq trapagain 517 b trapexit 518 #endif /* DDB || KGDB */ 519
Indexes created Tue Sep 30 20:09:53 GMT 2025