trap_subr.S revision 266001
1/*- 2 * Copyright (C) 2006-2009 Semihalf, Rafal Jaworowski <raj@semihalf.com> 3 * Copyright (C) 2006 Semihalf, Marian Balakowicz <m8@semihalf.com> 4 * Copyright (C) 2006 Juniper Networks, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 21 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 24 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 25 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 26 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $FreeBSD: stable/10/sys/powerpc/booke/trap_subr.S 266001 2014-05-14 03:09:37Z ian $ 30 */ 31/*- 32 * Copyright (C) 1995, 1996 Wolfgang Solfrank. 33 * Copyright (C) 1995, 1996 TooLs GmbH. 34 * All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. All advertising materials mentioning features or use of this software 45 * must display the following acknowledgement: 46 * This product includes software developed by TooLs GmbH. 47 * 4. The name of TooLs GmbH may not be used to endorse or promote products 48 * derived from this software without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 51 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 52 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 53 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 54 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 55 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 56 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 57 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 58 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 59 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 60 * 61 * from: $NetBSD: trap_subr.S,v 1.20 2002/04/22 23:20:08 kleink Exp $ 62 */ 63 64/* 65 * NOTICE: This is not a standalone file. to use it, #include it in 66 * your port's locore.S, like so: 67 * 68 * #include <powerpc/booke/trap_subr.S> 69 */ 70 71/* 72 * SPRG usage notes 73 * 74 * SPRG0 - pcpu pointer 75 * SPRG1 - all interrupts except TLB miss, critical, machine check 76 * SPRG2 - critical 77 * SPRG3 - machine check 78 * SPRG4-6 - scratch 79 * 80 */ 81 82/* Get the per-CPU data structure */ 83#define GET_CPUINFO(r) mfsprg0 r 84 85#define RES_GRANULE 32 86#define RES_LOCK 0 /* offset to the 'lock' word */ 87#define RES_RECURSE 4 /* offset to the 'recurse' word */ 88 89/* 90 * Standard interrupt prolog 91 * 92 * sprg_sp - SPRG{1-3} reg used to temporarily store the SP 93 * savearea - temp save area (pc_{tempsave, disisave, critsave, mchksave}) 94 * isrr0-1 - save restore registers with CPU state at interrupt time (may be 95 * SRR0-1, CSRR0-1, MCSRR0-1 96 * 97 * 1. saves in the given savearea: 98 * - R30-31 99 * - DEAR, ESR 100 * - xSRR0-1 101 * 102 * 2. saves CR -> R30 103 * 104 * 3. switches to kstack if needed 105 * 106 * 4. notes: 107 * - R31 can be used as scratch register until a new frame is layed on 108 * the stack with FRAME_SETUP 109 * 110 * - potential TLB miss: NO. Saveareas are always acessible via TLB1 111 * permanent entries, and within this prolog we do not dereference any 112 * locations potentially not in the TLB 113 */ 114#define STANDARD_PROLOG(sprg_sp, savearea, isrr0, isrr1) \ 115 mtspr sprg_sp, %r1; /* Save SP */ \ 116 GET_CPUINFO(%r1); /* Per-cpu structure */ \ 117 stw %r30, (savearea+CPUSAVE_R30)(%r1); \ 118 stw %r31, (savearea+CPUSAVE_R31)(%r1); \ 119 mfdear %r30; \ 120 mfesr %r31; \ 121 stw %r30, (savearea+CPUSAVE_BOOKE_DEAR)(%r1); \ 122 stw %r31, (savearea+CPUSAVE_BOOKE_ESR)(%r1); \ 123 mfspr %r30, isrr0; \ 124 mfspr %r31, isrr1; /* MSR at interrupt time */ \ 125 stw %r30, (savearea+CPUSAVE_SRR0)(%r1); \ 126 stw %r31, (savearea+CPUSAVE_SRR1)(%r1); \ 127 isync; \ 128 mfspr %r1, sprg_sp; /* Restore SP */ \ 129 mfcr %r30; /* Save CR */ \ 130 /* switch to per-thread kstack if intr taken in user mode */ \ 131 mtcr %r31; /* MSR at interrupt time */ \ 132 bf 17, 1f; \ 133 GET_CPUINFO(%r1); /* Per-cpu structure */ \ 134 lwz %r1, PC_CURPCB(%r1); /* Per-thread kernel stack */ \ 1351: 136 137#define STANDARD_CRIT_PROLOG(sprg_sp, savearea, isrr0, isrr1) \ 138 mtspr sprg_sp, %r1; /* Save SP */ \ 139 GET_CPUINFO(%r1); /* Per-cpu structure */ \ 140 stw %r30, (savearea+CPUSAVE_R30)(%r1); \ 141 stw %r31, (savearea+CPUSAVE_R31)(%r1); \ 142 mfdear %r30; \ 143 mfesr %r31; \ 144 stw %r30, (savearea+CPUSAVE_BOOKE_DEAR)(%r1); \ 145 stw %r31, (savearea+CPUSAVE_BOOKE_ESR)(%r1); \ 146 mfspr %r30, isrr0; \ 147 mfspr %r31, isrr1; /* MSR at interrupt time */ \ 148 stw %r30, (savearea+CPUSAVE_SRR0)(%r1); \ 149 stw %r31, (savearea+CPUSAVE_SRR1)(%r1); \ 150 mfspr %r30, SPR_SRR0; \ 151 mfspr %r31, SPR_SRR1; /* MSR at interrupt time */ \ 152 stw %r30, (savearea+CPUSAVE_SRR0+8)(%r1); \ 153 stw %r31, (savearea+CPUSAVE_SRR1+8)(%r1); \ 154 isync; \ 155 mfspr %r1, sprg_sp; /* Restore SP */ \ 156 mfcr %r30; /* Save CR */ \ 157 /* switch to per-thread kstack if intr taken in user mode */ \ 158 mtcr %r31; /* MSR at interrupt time */ \ 159 bf 17, 1f; \ 160 GET_CPUINFO(%r1); /* Per-cpu structure */ \ 161 lwz %r1, PC_CURPCB(%r1); /* Per-thread kernel stack */ \ 1621: 163 164/* 165 * FRAME_SETUP assumes: 166 * SPRG{1-3} SP at the time interrupt occured 167 * savearea r30-r31, DEAR, ESR, xSRR0-1 168 * r30 CR 169 * r31 scratch 170 * r1 kernel stack 171 * 172 * sprg_sp - SPRG reg containing SP at the time interrupt occured 173 * savearea - temp save 174 * exc - exception number (EXC_xxx) 175 * 176 * 1. sets a new frame 177 * 2. saves in the frame: 178 * - R0, R1 (SP at the time of interrupt), R2, LR, CR 179 * - R3-31 (R30-31 first restored from savearea) 180 * - XER, CTR, DEAR, ESR (from savearea), xSRR0-1 181 * 182 * Notes: 183 * - potential TLB miss: YES, since we make dereferences to kstack, which 184 * can happen not covered (we can have up to two DTLB misses if fortunate 185 * enough i.e. when kstack crosses page boundary and both pages are 186 * untranslated) 187 */ 188#define FRAME_SETUP(sprg_sp, savearea, exc) \ 189 mfspr %r31, sprg_sp; /* get saved SP */ \ 190 /* establish a new stack frame and put everything on it */ \ 191 stwu %r31, -FRAMELEN(%r1); \ 192 stw %r0, FRAME_0+8(%r1); /* save r0 in the trapframe */ \ 193 stw %r31, FRAME_1+8(%r1); /* save SP " " */ \ 194 stw %r2, FRAME_2+8(%r1); /* save r2 " " */ \ 195 mflr %r31; \ 196 stw %r31, FRAME_LR+8(%r1); /* save LR " " */ \ 197 stw %r30, FRAME_CR+8(%r1); /* save CR " " */ \ 198 GET_CPUINFO(%r2); \ 199 lwz %r30, (savearea+CPUSAVE_R30)(%r2); /* get saved r30 */ \ 200 lwz %r31, (savearea+CPUSAVE_R31)(%r2); /* get saved r31 */ \ 201 /* save R3-31 */ \ 202 stmw %r3, FRAME_3+8(%r1) ; \ 203 /* save DEAR, ESR */ \ 204 lwz %r28, (savearea+CPUSAVE_BOOKE_DEAR)(%r2); \ 205 lwz %r29, (savearea+CPUSAVE_BOOKE_ESR)(%r2); \ 206 stw %r28, FRAME_BOOKE_DEAR+8(%r1); \ 207 stw %r29, FRAME_BOOKE_ESR+8(%r1); \ 208 /* save XER, CTR, exc number */ \ 209 mfxer %r3; \ 210 mfctr %r4; \ 211 stw %r3, FRAME_XER+8(%r1); \ 212 stw %r4, FRAME_CTR+8(%r1); \ 213 li %r5, exc; \ 214 stw %r5, FRAME_EXC+8(%r1); \ 215 /* save DBCR0 */ \ 216 mfspr %r3, SPR_DBCR0; \ 217 stw %r3, FRAME_BOOKE_DBCR0+8(%r1); \ 218 /* save xSSR0-1 */ \ 219 lwz %r30, (savearea+CPUSAVE_SRR0)(%r2); \ 220 lwz %r31, (savearea+CPUSAVE_SRR1)(%r2); \ 221 stw %r30, FRAME_SRR0+8(%r1); \ 222 stw %r31, FRAME_SRR1+8(%r1); \ 223 lwz %r2,PC_CURTHREAD(%r2) /* set curthread pointer */ 224 225/* 226 * 227 * isrr0-1 - save restore registers to restore CPU state to (may be 228 * SRR0-1, CSRR0-1, MCSRR0-1 229 * 230 * Notes: 231 * - potential TLB miss: YES. The deref'd kstack may be not covered 232 */ 233#define FRAME_LEAVE(isrr0, isrr1) \ 234 /* restore CTR, XER, LR, CR */ \ 235 lwz %r4, FRAME_CTR+8(%r1); \ 236 lwz %r5, FRAME_XER+8(%r1); \ 237 lwz %r6, FRAME_LR+8(%r1); \ 238 lwz %r7, FRAME_CR+8(%r1); \ 239 mtctr %r4; \ 240 mtxer %r5; \ 241 mtlr %r6; \ 242 mtcr %r7; \ 243 /* restore DBCR0 */ \ 244 lwz %r4, FRAME_BOOKE_DBCR0+8(%r1); \ 245 mtspr SPR_DBCR0, %r4; \ 246 /* restore xSRR0-1 */ \ 247 lwz %r30, FRAME_SRR0+8(%r1); \ 248 lwz %r31, FRAME_SRR1+8(%r1); \ 249 mtspr isrr0, %r30; \ 250 mtspr isrr1, %r31; \ 251 /* restore R2-31, SP */ \ 252 lmw %r2, FRAME_2+8(%r1) ; \ 253 lwz %r0, FRAME_0+8(%r1); \ 254 lwz %r1, FRAME_1+8(%r1); \ 255 isync 256 257/* 258 * TLB miss prolog 259 * 260 * saves LR, CR, SRR0-1, R20-31 in the TLBSAVE area 261 * 262 * Notes: 263 * - potential TLB miss: NO. It is crucial that we do not generate a TLB 264 * miss within the TLB prolog itself! 265 * - TLBSAVE is always translated 266 */ 267#define TLB_PROLOG \ 268 mtsprg4 %r1; /* Save SP */ \ 269 mtsprg5 %r28; \ 270 mtsprg6 %r29; \ 271 /* calculate TLB nesting level and TLBSAVE instance address */ \ 272 GET_CPUINFO(%r1); /* Per-cpu structure */ \ 273 lwz %r28, PC_BOOKE_TLB_LEVEL(%r1); \ 274 rlwinm %r29, %r28, 6, 23, 25; /* 4 x TLBSAVE_LEN */ \ 275 addi %r28, %r28, 1; \ 276 stw %r28, PC_BOOKE_TLB_LEVEL(%r1); \ 277 addi %r29, %r29, PC_BOOKE_TLBSAVE@l; \ 278 add %r1, %r1, %r29; /* current TLBSAVE ptr */ \ 279 \ 280 /* save R20-31 */ \ 281 mfsprg5 %r28; \ 282 mfsprg6 %r29; \ 283 stmw %r20, (TLBSAVE_BOOKE_R20)(%r1); \ 284 /* save LR, CR */ \ 285 mflr %r30; \ 286 mfcr %r31; \ 287 stw %r30, (TLBSAVE_BOOKE_LR)(%r1); \ 288 stw %r31, (TLBSAVE_BOOKE_CR)(%r1); \ 289 /* save SRR0-1 */ \ 290 mfsrr0 %r30; /* execution addr at interrupt time */ \ 291 mfsrr1 %r31; /* MSR at interrupt time*/ \ 292 stw %r30, (TLBSAVE_BOOKE_SRR0)(%r1); /* save SRR0 */ \ 293 stw %r31, (TLBSAVE_BOOKE_SRR1)(%r1); /* save SRR1 */ \ 294 isync; \ 295 mfsprg4 %r1 296 297/* 298 * restores LR, CR, SRR0-1, R20-31 from the TLBSAVE area 299 * 300 * same notes as for the TLB_PROLOG 301 */ 302#define TLB_RESTORE \ 303 mtsprg4 %r1; /* Save SP */ \ 304 GET_CPUINFO(%r1); /* Per-cpu structure */ \ 305 /* calculate TLB nesting level and TLBSAVE instance addr */ \ 306 lwz %r28, PC_BOOKE_TLB_LEVEL(%r1); \ 307 subi %r28, %r28, 1; \ 308 stw %r28, PC_BOOKE_TLB_LEVEL(%r1); \ 309 rlwinm %r29, %r28, 6, 23, 25; /* 4 x TLBSAVE_LEN */ \ 310 addi %r29, %r29, PC_BOOKE_TLBSAVE@l; \ 311 add %r1, %r1, %r29; \ 312 \ 313 /* restore LR, CR */ \ 314 lwz %r30, (TLBSAVE_BOOKE_LR)(%r1); \ 315 lwz %r31, (TLBSAVE_BOOKE_CR)(%r1); \ 316 mtlr %r30; \ 317 mtcr %r31; \ 318 /* restore SRR0-1 */ \ 319 lwz %r30, (TLBSAVE_BOOKE_SRR0)(%r1); \ 320 lwz %r31, (TLBSAVE_BOOKE_SRR1)(%r1); \ 321 mtsrr0 %r30; \ 322 mtsrr1 %r31; \ 323 /* restore R20-31 */ \ 324 lmw %r20, (TLBSAVE_BOOKE_R20)(%r1); \ 325 mfsprg4 %r1 326 327#ifdef SMP 328#define TLB_LOCK \ 329 GET_CPUINFO(%r20); \ 330 lwz %r21, PC_CURTHREAD(%r20); \ 331 lwz %r22, PC_BOOKE_TLB_LOCK(%r20); \ 332 \ 3331: lwarx %r23, 0, %r22; \ 334 cmpwi %r23, TLB_UNLOCKED; \ 335 beq 2f; \ 336 \ 337 /* check if this is recursion */ \ 338 cmplw cr0, %r21, %r23; \ 339 bne- 1b; \ 340 \ 3412: /* try to acquire lock */ \ 342 stwcx. %r21, 0, %r22; \ 343 bne- 1b; \ 344 \ 345 /* got it, update recursion counter */ \ 346 lwz %r21, RES_RECURSE(%r22); \ 347 addi %r21, %r21, 1; \ 348 stw %r21, RES_RECURSE(%r22); \ 349 isync; \ 350 msync 351 352#define TLB_UNLOCK \ 353 GET_CPUINFO(%r20); \ 354 lwz %r21, PC_CURTHREAD(%r20); \ 355 lwz %r22, PC_BOOKE_TLB_LOCK(%r20); \ 356 \ 357 /* update recursion counter */ \ 358 lwz %r23, RES_RECURSE(%r22); \ 359 subi %r23, %r23, 1; \ 360 stw %r23, RES_RECURSE(%r22); \ 361 \ 362 cmpwi %r23, 0; \ 363 bne 1f; \ 364 isync; \ 365 msync; \ 366 \ 367 /* release the lock */ \ 368 li %r23, TLB_UNLOCKED; \ 369 stw %r23, 0(%r22); \ 3701: isync; \ 371 msync 372#else 373#define TLB_LOCK 374#define TLB_UNLOCK 375#endif /* SMP */ 376 377#define INTERRUPT(label) \ 378 .globl label; \ 379 .align 5; \ 380 CNAME(label): 381 382/* 383 * Interrupt handling routines in BookE can be flexibly placed and do not have 384 * to live in pre-defined vectors location. Note they need to be TLB-mapped at 385 * all times in order to be able to handle exceptions. We thus arrange for 386 * them to be part of kernel text which is always TLB-accessible. 387 * 388 * The interrupt handling routines have to be 16 bytes aligned: we align them 389 * to 32 bytes (cache line length) which supposedly performs better. 390 * 391 */ 392 .text 393 .globl CNAME(interrupt_vector_base) 394 .align 5 395interrupt_vector_base: 396 397/***************************************************************************** 398 * Critical input interrupt 399 ****************************************************************************/ 400INTERRUPT(int_critical_input) 401 STANDARD_PROLOG(SPR_SPRG2, PC_BOOKE_CRITSAVE, SPR_CSRR0, SPR_CSRR1) 402 FRAME_SETUP(SPR_SPRG2, PC_BOOKE_CRITSAVE, EXC_CRIT) 403 addi %r3, %r1, 8 404 bl CNAME(powerpc_crit_interrupt) 405 FRAME_LEAVE(SPR_CSRR0, SPR_CSRR1) 406 rfci 407 408 409/***************************************************************************** 410 * Machine check interrupt 411 ****************************************************************************/ 412INTERRUPT(int_machine_check) 413 STANDARD_PROLOG(SPR_SPRG3, PC_BOOKE_MCHKSAVE, SPR_MCSRR0, SPR_MCSRR1) 414 FRAME_SETUP(SPR_SPRG3, PC_BOOKE_MCHKSAVE, EXC_MCHK) 415 addi %r3, %r1, 8 416 bl CNAME(powerpc_mchk_interrupt) 417 FRAME_LEAVE(SPR_MCSRR0, SPR_MCSRR1) 418 rfmci 419 420 421/***************************************************************************** 422 * Data storage interrupt 423 ****************************************************************************/ 424INTERRUPT(int_data_storage) 425 STANDARD_PROLOG(SPR_SPRG1, PC_DISISAVE, SPR_SRR0, SPR_SRR1) 426 FRAME_SETUP(SPR_SPRG1, PC_DISISAVE, EXC_DSI) 427 b trap_common 428 429 430/***************************************************************************** 431 * Instruction storage interrupt 432 ****************************************************************************/ 433INTERRUPT(int_instr_storage) 434 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 435 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_ISI) 436 b trap_common 437 438 439/***************************************************************************** 440 * External input interrupt 441 ****************************************************************************/ 442INTERRUPT(int_external_input) 443 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 444 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_EXI) 445 addi %r3, %r1, 8 446 bl CNAME(powerpc_extr_interrupt) 447 b trapexit 448 449 450INTERRUPT(int_alignment) 451 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 452 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_ALI) 453 b trap_common 454 455 456INTERRUPT(int_program) 457 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 458 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_PGM) 459 b trap_common 460 461 462/***************************************************************************** 463 * System call 464 ****************************************************************************/ 465INTERRUPT(int_syscall) 466 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 467 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_SC) 468 b trap_common 469 470 471/***************************************************************************** 472 * Decrementer interrupt 473 ****************************************************************************/ 474INTERRUPT(int_decrementer) 475 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 476 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_DECR) 477 addi %r3, %r1, 8 478 bl CNAME(powerpc_decr_interrupt) 479 b trapexit 480 481 482/***************************************************************************** 483 * Fixed interval timer 484 ****************************************************************************/ 485INTERRUPT(int_fixed_interval_timer) 486 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 487 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_FIT) 488 b trap_common 489 490 491/***************************************************************************** 492 * Watchdog interrupt 493 ****************************************************************************/ 494INTERRUPT(int_watchdog) 495 STANDARD_PROLOG(SPR_SPRG1, PC_TEMPSAVE, SPR_SRR0, SPR_SRR1) 496 FRAME_SETUP(SPR_SPRG1, PC_TEMPSAVE, EXC_WDOG) 497 b trap_common 498 499 500/***************************************************************************** 501 * Data TLB miss interrupt 502 * 503 * There can be nested TLB misses - while handling a TLB miss we reference 504 * data structures that may be not covered by translations. We support up to 505 * TLB_NESTED_MAX-1 nested misses. 506 * 507 * Registers use: 508 * r31 - dear 509 * r30 - unused 510 * r29 - saved mas0 511 * r28 - saved mas1 512 * r27 - saved mas2 513 * r26 - pmap address 514 * r25 - pte address 515 * 516 * r20:r23 - scratch registers 517 ****************************************************************************/ 518INTERRUPT(int_data_tlb_error) 519 TLB_PROLOG 520 TLB_LOCK 521 522 mfdear %r31 523 524 /* 525 * Save MAS0-MAS2 registers. There might be another tlb miss during 526 * pte lookup overwriting current contents (which was hw filled). 527 */ 528 mfspr %r29, SPR_MAS0 529 mfspr %r28, SPR_MAS1 530 mfspr %r27, SPR_MAS2 531 532 /* Check faulting address. */ 533 lis %r21, VM_MAXUSER_ADDRESS@h 534 ori %r21, %r21, VM_MAXUSER_ADDRESS@l 535 cmplw cr0, %r31, %r21 536 blt search_user_pmap 537 538 /* If it's kernel address, allow only supervisor mode misses. */ 539 mfsrr1 %r21 540 mtcr %r21 541 bt 17, search_failed /* check MSR[PR] */ 542 543search_kernel_pmap: 544 /* Load r26 with kernel_pmap address */ 545 lis %r26, kernel_pmap_store@h 546 ori %r26, %r26, kernel_pmap_store@l 547 548 /* Force kernel tid, set TID to 0 in MAS1. */ 549 li %r21, 0 550 rlwimi %r28, %r21, 0, 8, 15 /* clear TID bits */ 551 552tlb_miss_handle: 553 /* This may result in nested tlb miss. */ 554 bl pte_lookup /* returns PTE address in R25 */ 555 556 cmpwi %r25, 0 /* pte found? */ 557 beq search_failed 558 559 /* Finish up, write TLB entry. */ 560 bl tlb_fill_entry 561 562tlb_miss_return: 563 TLB_UNLOCK 564 TLB_RESTORE 565 rfi 566 567search_user_pmap: 568 /* Load r26 with current user space process pmap */ 569 GET_CPUINFO(%r26) 570 lwz %r26, PC_CURPMAP(%r26) 571 572 b tlb_miss_handle 573 574search_failed: 575 /* 576 * Whenever we don't find a TLB mapping in PT, set a TLB0 entry with 577 * the faulting virtual address anyway, but put a fake RPN and no 578 * access rights. This should cause a following {D,I}SI exception. 579 */ 580 lis %r23, 0xffff0000@h /* revoke all permissions */ 581 582 /* Load MAS registers. */ 583 mtspr SPR_MAS0, %r29 584 isync 585 mtspr SPR_MAS1, %r28 586 isync 587 mtspr SPR_MAS2, %r27 588 isync 589 mtspr SPR_MAS3, %r23 590 isync 591 592 tlbwe 593 msync 594 isync 595 b tlb_miss_return 596 597/***************************************************************************** 598 * 599 * Return pte address that corresponds to given pmap/va. If there is no valid 600 * entry return 0. 601 * 602 * input: r26 - pmap 603 * input: r31 - dear 604 * output: r25 - pte address 605 * 606 * scratch regs used: r21 607 * 608 ****************************************************************************/ 609pte_lookup: 610 cmpwi %r26, 0 611 beq 1f /* fail quickly if pmap is invalid */ 612 613 srwi %r21, %r31, PDIR_SHIFT /* pdir offset */ 614 slwi %r21, %r21, PDIR_ENTRY_SHIFT /* multiply by pdir entry size */ 615 616 addi %r25, %r26, PM_PDIR /* pmap pm_dir[] address */ 617 add %r25, %r25, %r21 /* offset within pm_pdir[] table */ 618 /* 619 * Get ptbl address, i.e. pmap->pm_pdir[pdir_idx] 620 * This load may cause a Data TLB miss for non-kernel pmap! 621 */ 622 lwz %r25, 0(%r25) 623 cmpwi %r25, 0 624 beq 2f 625 626 lis %r21, PTBL_MASK@h 627 ori %r21, %r21, PTBL_MASK@l 628 and %r21, %r21, %r31 629 630 /* ptbl offset, multiply by ptbl entry size */ 631 srwi %r21, %r21, (PTBL_SHIFT - PTBL_ENTRY_SHIFT) 632 633 add %r25, %r25, %r21 /* address of pte entry */ 634 /* 635 * Get pte->flags 636 * This load may cause a Data TLB miss for non-kernel pmap! 637 */ 638 lwz %r21, PTE_FLAGS(%r25) 639 andis. %r21, %r21, PTE_VALID@h 640 bne 2f 6411: 642 li %r25, 0 6432: 644 blr 645 646/***************************************************************************** 647 * 648 * Load MAS1-MAS3 registers with data, write TLB entry 649 * 650 * input: 651 * r29 - mas0 652 * r28 - mas1 653 * r27 - mas2 654 * r25 - pte 655 * 656 * output: none 657 * 658 * scratch regs: r21-r23 659 * 660 ****************************************************************************/ 661tlb_fill_entry: 662 /* 663 * Update PTE flags: we have to do it atomically, as pmap_protect() 664 * running on other CPUs could attempt to update the flags at the same 665 * time. 666 */ 667 li %r23, PTE_FLAGS 6681: 669 lwarx %r21, %r23, %r25 /* get pte->flags */ 670 oris %r21, %r21, PTE_REFERENCED@h /* set referenced bit */ 671 672 andi. %r22, %r21, (PTE_SW | PTE_UW)@l /* check if writable */ 673 beq 2f 674 oris %r21, %r21, PTE_MODIFIED@h /* set modified bit */ 6752: 676 stwcx. %r21, %r23, %r25 /* write it back */ 677 bne- 1b 678 679 /* Update MAS2. */ 680 rlwimi %r27, %r21, 0, 27, 30 /* insert WIMG bits from pte */ 681 682 /* Setup MAS3 value in r23. */ 683 lwz %r23, PTE_RPN(%r25) /* get pte->rpn */ 684 685 rlwimi %r23, %r21, 24, 26, 31 /* insert protection bits from pte */ 686 687 /* Load MAS registers. */ 688 mtspr SPR_MAS0, %r29 689 isync 690 mtspr SPR_MAS1, %r28 691 isync 692 mtspr SPR_MAS2, %r27 693 isync 694 mtspr SPR_MAS3, %r23 695 isync 696 697 tlbwe 698 isync 699 msync 700 blr 701 702/***************************************************************************** 703 * Instruction TLB miss interrupt 704 * 705 * Same notes as for the Data TLB miss 706 ****************************************************************************/ 707INTERRUPT(int_inst_tlb_error) 708 TLB_PROLOG 709 TLB_LOCK 710 711 mfsrr0 %r31 /* faulting address */ 712 713 /* 714 * Save MAS0-MAS2 registers. There might be another tlb miss during pte 715 * lookup overwriting current contents (which was hw filled). 716 */ 717 mfspr %r29, SPR_MAS0 718 mfspr %r28, SPR_MAS1 719 mfspr %r27, SPR_MAS2 720 721 mfsrr1 %r21 722 mtcr %r21 723 724 /* check MSR[PR] */ 725 bt 17, search_user_pmap 726 b search_kernel_pmap 727 728 729 .globl interrupt_vector_top 730interrupt_vector_top: 731 732/***************************************************************************** 733 * Debug interrupt 734 ****************************************************************************/ 735INTERRUPT(int_debug) 736 STANDARD_CRIT_PROLOG(SPR_SPRG2, PC_BOOKE_CRITSAVE, SPR_CSRR0, SPR_CSRR1) 737 FRAME_SETUP(SPR_SPRG2, PC_BOOKE_CRITSAVE, EXC_DEBUG) 738 GET_CPUINFO(%r3) 739 lwz %r3, (PC_BOOKE_CRITSAVE+CPUSAVE_SRR0)(%r3) 740 lis %r4, interrupt_vector_base@ha 741 addi %r4, %r4, interrupt_vector_base@l 742 cmplw cr0, %r3, %r4 743 blt 1f 744 lis %r4, interrupt_vector_top@ha 745 addi %r4, %r4, interrupt_vector_top@l 746 cmplw cr0, %r3, %r4 747 bge 1f 748 /* Disable single-stepping for the interrupt handlers. */ 749 lwz %r3, FRAME_SRR1+8(%r1); 750 rlwinm %r3, %r3, 0, 23, 21 751 stw %r3, FRAME_SRR1+8(%r1); 752 /* Restore srr0 and srr1 as they could have been clobbered. */ 753 GET_CPUINFO(%r4) 754 lwz %r3, (PC_BOOKE_CRITSAVE+CPUSAVE_SRR0+8)(%r4); 755 mtspr SPR_SRR0, %r3 756 lwz %r4, (PC_BOOKE_CRITSAVE+CPUSAVE_SRR1+8)(%r4); 757 mtspr SPR_SRR1, %r4 758 b 9f 7591: 760 addi %r3, %r1, 8 761 bl CNAME(trap) 762 /* 763 * Handle ASTs, needed for proper support of single-stepping. 764 * We actually need to return to the process with an rfi. 765 */ 766 b trapexit 7679: 768 FRAME_LEAVE(SPR_CSRR0, SPR_CSRR1) 769 rfci 770 771 772/***************************************************************************** 773 * Common trap code 774 ****************************************************************************/ 775trap_common: 776 /* Call C trap dispatcher */ 777 addi %r3, %r1, 8 778 bl CNAME(trap) 779 780 .globl CNAME(trapexit) /* exported for db_backtrace use */ 781CNAME(trapexit): 782 /* disable interrupts */ 783 wrteei 0 784 785 /* Test AST pending - makes sense for user process only */ 786 lwz %r5, FRAME_SRR1+8(%r1) 787 mtcr %r5 788 bf 17, 1f 789 790 GET_CPUINFO(%r3) 791 lwz %r4, PC_CURTHREAD(%r3) 792 lwz %r4, TD_FLAGS(%r4) 793 lis %r5, (TDF_ASTPENDING | TDF_NEEDRESCHED)@h 794 ori %r5, %r5, (TDF_ASTPENDING | TDF_NEEDRESCHED)@l 795 and. %r4, %r4, %r5 796 beq 1f 797 798 /* re-enable interrupts before calling ast() */ 799 wrteei 1 800 801 addi %r3, %r1, 8 802 bl CNAME(ast) 803 .globl CNAME(asttrapexit) /* db_backtrace code sentinel #2 */ 804CNAME(asttrapexit): 805 b trapexit /* test ast ret value ? */ 8061: 807 FRAME_LEAVE(SPR_SRR0, SPR_SRR1) 808 rfi 809 810 811#if defined(KDB) 812/* 813 * Deliberate entry to dbtrap 814 */ 815 .globl CNAME(breakpoint) 816CNAME(breakpoint): 817 mtsprg1 %r1 818 mfmsr %r3 819 mtsrr1 %r3 820 andi. %r3, %r3, ~(PSL_EE | PSL_ME)@l 821 mtmsr %r3 /* disable interrupts */ 822 isync 823 GET_CPUINFO(%r3) 824 stw %r30, (PC_DBSAVE+CPUSAVE_R30)(%r3) 825 stw %r31, (PC_DBSAVE+CPUSAVE_R31)(%r3) 826 827 mflr %r31 828 mtsrr0 %r31 829 830 mfdear %r30 831 mfesr %r31 832 stw %r30, (PC_DBSAVE+CPUSAVE_BOOKE_DEAR)(%r3) 833 stw %r31, (PC_DBSAVE+CPUSAVE_BOOKE_ESR)(%r3) 834 835 mfsrr0 %r30 836 mfsrr1 %r31 837 stw %r30, (PC_DBSAVE+CPUSAVE_SRR0)(%r3) 838 stw %r31, (PC_DBSAVE+CPUSAVE_SRR1)(%r3) 839 isync 840 841 mfcr %r30 842 843/* 844 * Now the kdb trap catching code. 845 */ 846dbtrap: 847 FRAME_SETUP(SPR_SPRG1, PC_DBSAVE, EXC_DEBUG) 848/* Call C trap code: */ 849 addi %r3, %r1, 8 850 bl CNAME(db_trap_glue) 851 or. %r3, %r3, %r3 852 bne dbleave 853/* This wasn't for KDB, so switch to real trap: */ 854 b trap_common 855 856dbleave: 857 FRAME_LEAVE(SPR_SRR0, SPR_SRR1) 858 rfi 859#endif /* KDB */ 860 861#ifdef SMP 862ENTRY(tlb_lock) 863 GET_CPUINFO(%r5) 864 lwz %r5, PC_CURTHREAD(%r5) 8651: lwarx %r4, 0, %r3 866 cmpwi %r4, TLB_UNLOCKED 867 bne 1b 868 stwcx. %r5, 0, %r3 869 bne- 1b 870 isync 871 msync 872 blr 873 874ENTRY(tlb_unlock) 875 isync 876 msync 877 li %r4, TLB_UNLOCKED 878 stw %r4, 0(%r3) 879 isync 880 msync 881 blr 882 883/* 884 * TLB miss spin locks. For each CPU we have a reservation granule (32 bytes); 885 * only a single word from this granule will actually be used as a spin lock 886 * for mutual exclusion between TLB miss handler and pmap layer that 887 * manipulates page table contents. 888 */ 889 .data 890 .align 5 891GLOBAL(tlb0_miss_locks) 892 .space RES_GRANULE * MAXCPU 893#endif 894