4xx_locore.S revision 1.1.2.3
1 /* $NetBSD: 4xx_locore.S,v 1.1.2.3 2002/12/19 15:52:19 thorpej 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 * This is not a standalone file. To use it, #inlcude it at 71 * the end of your port's locore.S 72 */ 73 74 /* 75 * Taken straight from Walnut's locore.S, with the following attribution: 76 * $OpenBSD: locore.S,v 1.4 1997/01/26 09:06:38 rahnds Exp $ 77 */ 78 79 /* 80 * No processes are runnable, so loop waiting for one. 81 * Separate label here for accounting purposes. 82 * When we get here, interrupts are off (MSR[EE]=0) and sched_lock is held. 83 */ 84 ASENTRY(Idle) 85 lis 8,_C_LABEL(sched_whichqs)@ha 86 lwz 9,_C_LABEL(sched_whichqs)@l(8) 87 88 or. 9,9,9 89 bne- .Lsw1 /* at least one queue non-empty */ 90 91 wrteei 1 /* reenable ints again */ 92 93 /* May do some power saving here? */ 94 /* Check if we can use power saving mode */ 95 lis 8,_C_LABEL(powersave)@ha 96 lwz 9,_C_LABEL(powersave)@l(8) 97 98 or. 9,9,9 99 beq 1f 100 101 /* TODO: Enter power saving mode here */ 102 1: 103 104 wrteei 0 /* disable interrupts while manipulating runque */ 105 106 b _ASM_LABEL(Idle) 107 108 /* 109 * switch_exit(struct lwp *l) 110 * switch_exit gets called from cpu_exit to complete the exit procedure. 111 */ 112 ENTRY(switch_lwp_exit) 113 /* First switch to the idle pcb/kernel stack */ 114 lis 6,idle_u@ha 115 lwz 6,idle_u@l(6) 116 lis 7,_C_LABEL(curpcb)@ha 117 stw 6,_C_LABEL(curpcb)@l(7) 118 addi 1,6,USPACE-16 /* 16 bytes are reserved at stack top */ 119 /* 120 * Schedule the vmspace and stack to be freed (the proc arg is 121 * already in r3). 122 */ 123 bl _C_LABEL(lwp_exit2) 124 125 b finish_switch_exit 126 127 /* 128 * switch_exit(struct lwp *l) 129 * switch_exit gets called from cpu_exit to complete the exit procedure. 130 */ 131 ENTRY(switch_exit) 132 /* First switch to the idle pcb/kernel stack */ 133 lis 6,idle_u@ha 134 lwz 6,idle_u@l(6) 135 lis 7,_C_LABEL(curpcb)@ha 136 stw 6,_C_LABEL(curpcb)@l(7) 137 addi 1,6,USPACE-16 /* 16 bytes are reserved at stack top */ 138 /* 139 * Schedule the vmspace and stack to be freed (the proc arg is 140 * already in r3). 141 */ 142 bl _C_LABEL(exit2) 143 144 finish_switch_exit: 145 /* Fall through to cpu_switch to actually select another proc */ 146 li 3,0 /* indicate exited process */ 147 148 /* 149 * void cpu_switch(struct lwp *l) 150 * Find a runnable process and switch to it. 151 */ 152 /* XXX noprofile? --thorpej (at) netbsd.org */ 153 ENTRY(cpu_switch) 154 mflr 0 /* save lr */ 155 stw 0,4(1) 156 stwu 1,-16(1) 157 stw 31,12(1) 158 stw 30,8(1) 159 160 mr 30,3 161 lis 3,_C_LABEL(curlwp)@ha 162 xor 31,31,31 163 stw 31,_C_LABEL(curlwp)@l(3) /* Zero to not accumulate cpu time */ 164 lis 3,_C_LABEL(curpcb)@ha 165 lwz 31,_C_LABEL(curpcb)@l(3) 166 167 xor 3,3,3 168 bl _C_LABEL(lcsplx) 169 stw 3,PCB_SPL(31) /* save spl */ 170 171 wrteei 0 /* disable interrupts while manipulating runque */ 172 173 /* Find a new process */ 174 lis 8,_C_LABEL(sched_whichqs)@ha 175 lwz 9,_C_LABEL(sched_whichqs)@l(8) 176 177 or. 9,9,9 178 beq- _ASM_LABEL(Idle) /* all queues empty */ 179 .Lsw1: 180 cntlzw 10,9 181 lis 4,_C_LABEL(sched_qs)@ha 182 addi 4,4,_C_LABEL(sched_qs)@l 183 slwi 3,10,3 184 add 3,3,4 /* select queue */ 185 186 lwz 31,L_FORW(3) /* unlink first proc from queue */ 187 lwz 4,L_FORW(31) 188 stw 4,L_FORW(3) 189 stw 3,L_BACK(4) 190 191 cmpl 0,3,4 /* queue empty? */ 192 bne 1f 193 194 lis 3,0x80000000@h 195 srw 3,3,10 196 andc 9,9,3 197 stw 9,_C_LABEL(sched_whichqs)@l(8) /* mark it empty */ 198 199 1: 200 /* just did this resched thing */ 201 xor 3,3,3 202 lis 4,_C_LABEL(want_resched)@ha 203 stw 3,_C_LABEL(want_resched)@l(4) 204 205 stw 3,L_BACK(31) /* probably superfluous */ 206 207 /* Process now running on a processor. */ 208 li 3,LSONPROC /* l->l_stat = LSONPROC */ 209 stw 3,L_STAT(31) 210 211 /* record new process */ 212 lis 4,_C_LABEL(curlwp)@ha 213 stw 31,_C_LABEL(curlwp)@l(4) 214 215 wrteei 1 /* Now we can interrupt again */ 216 217 li 3,0 /* if it's the same lwp, return 0 */ 218 cmpl 0,31,30 /* is it the same process? */ 219 beq switch_return 220 221 or. 30,30,30 /* old process was exiting? */ 222 beq switch_exited 223 224 #ifndef PPC_IBM4XX 225 mfsr 10,USER_SR /* save USER_SR for copyin/copyout */ 226 #else 227 li 10,0 /* no SR for 4xx CPUs */ 228 #endif 229 mfcr 11 /* save cr */ 230 mr 12,2 /* save r2 */ 231 stwu 1,-SFRAMELEN(1) /* still running on old stack */ 232 stmw 10,8(1) 233 lwz 3,L_ADDR(30) 234 stw 1,PCB_SP(3) /* save SP */ 235 236 switch_exited: 237 wrteei 0 /* disable interrupts while actually switching */ 238 239 /* indicate new pcb */ 240 lwz 4,L_ADDR(31) 241 lis 5,_C_LABEL(curpcb)@ha 242 stw 4,_C_LABEL(curpcb)@l(5) 243 244 /* save real pmap pointer for spill fill */ 245 lwz 5,PCB_PMR(4) 246 lis 6,_C_LABEL(curpm)@ha 247 stwu 5,_C_LABEL(curpm)@l(6) 248 stwcx. 5,0,6 /* clear possible reservation */ 249 250 /* Switch to the new virtual space */ 251 /* Do not have to do anything here. TLB PID gets updated on return from trap. */ 252 253 lwz 1,PCB_SP(4) /* get new procs SP */ 254 255 wrteei 1 /* interrupts are okay again */ 256 257 lmw 10,8(1) /* get other regs */ 258 lwz 1,0(1) /* get saved SP */ 259 mr 2,12 /* get saved r2 */ 260 mtcr 11 /* get saved cr */ 261 isync 262 li 3,1 /* switched lwps */ 263 264 switch_return: 265 mr 30,3 /* save return value */ 266 267 lwz 3,PCB_SPL(4) 268 bl _C_LABEL(lcsplx) 269 270 0: 271 lis 3,_C_LABEL(curpm)@ha 272 addi 3,3,_C_LABEL(curpm)@l /* Do we need a context? */ 273 lwz 4,PM_CTX(3) 274 cmpwi 4,0 275 # mtspr SPR_SPR0,4 /* Always keep the current ctx here */ 276 mr 3,30 277 bne 1f 278 bl _C_LABEL(ctx_alloc) 279 b 0b /* Reload */ 280 1: 281 lwz 31,12(1) 282 lwz 30,8(1) 283 addi 1,1,16 284 lwz 0,4(1) 285 mtlr 0 286 blr 287 288 /* 289 * void cpu_preempt(struct lwp *current, struct lwp *new)) 290 * Find a runnable process and switch to it. 291 */ 292 ENTRY(cpu_preempt) 293 mflr 0 /* save lr */ 294 stw 0,4(1) 295 stwu 1,-20(1) 296 stw 31,16(1) 297 stw 30,12(1) 298 stw 29,8(1) 299 300 mr 30,3 301 mr 29,4 302 lis 3,_C_LABEL(curlwp)@ha 303 xor 31,31,31 304 stw 31,_C_LABEL(curlwp)@l(3) /* Zero to not accumulate cpu time */ 305 lis 3,_C_LABEL(curpcb)@ha 306 lwz 31,_C_LABEL(curpcb)@l(3) 307 308 xor 3,3,3 309 bl _C_LABEL(lcsplx) 310 stw 3,PCB_SPL(31) /* save spl */ 311 312 wrteei 0 /* disable interrupts while manipulating runque */ 313 314 /* Find a new process */ 315 xor 3,3,3 316 317 mr 31,29 /* r31 = newlwp */ 318 lwz 4,L_BACK(31) /* r4 = newlwp->l_back */ 319 stw 3,L_BACK(31) /* newlwp->l_back = NULL */ 320 lwz 3,L_FORW(31) /* r3 = newlwp->l_forw */ 321 stw 4,L_BACK(3) /* r3->l_back = r4 */ 322 stw 3,L_FORW(4) /* r4->l_forw = r3 */ 323 324 cmpl 0,4,3 /* queue empty? */ 325 bne 1f 326 327 /* so now r31 is newlwp and r3/r4 are scratch again */ 328 329 lis 8,_C_LABEL(sched_whichqs)@ha 330 lwz 4,_C_LABEL(sched_whichqs)@l(8) 331 332 lbz 3,L_PRIORITY(31) 333 li 9,2 334 srw 3,3,9 /* r3 = newlwp->l_priority / 4 */ 335 li 9,1 336 slw 3,9,3 /* r3 = 1 << r3 */ 337 andc 4,4,3 /* sched_whichqs &= ~r3 */ 338 stw 4,_C_LABEL(sched_whichqs)@l(8) /* mark it empty */ 339 340 1: 341 /* just did this resched thing */ 342 xor 3,3,3 343 lis 4,_C_LABEL(want_resched)@ha 344 stw 3,_C_LABEL(want_resched)@l(4) 345 346 stw 3,L_BACK(31) /* probably superfluous */ 347 348 /* Process now running on a processor. */ 349 li 3,LSONPROC /* l->l_stat = LSONPROC */ 350 stw 3,L_STAT(31) 351 352 /* record new process */ 353 lis 4,_C_LABEL(curlwp)@ha 354 stw 31,_C_LABEL(curlwp)@l(4) 355 356 wrteei 1 /* Now we can interrupt again */ 357 358 cmpl 0,31,30 /* is it the same process? */ 359 beq preempt_return 360 361 or. 30,30,30 /* old process was exiting? */ 362 beq preempt_exited 363 364 #ifndef PPC_IBM4XX 365 mfsr 10,USER_SR /* save USER_SR for copyin/copyout */ 366 #else 367 li 10,0 /* no SR for 4xx CPUs */ 368 #endif 369 mfcr 11 /* save cr */ 370 mr 12,2 /* save r2 */ 371 stwu 1,-SFRAMELEN(1) /* still running on old stack */ 372 stmw 10,8(1) 373 lwz 3,L_ADDR(30) 374 stw 1,PCB_SP(3) /* save SP */ 375 376 preempt_exited: 377 wrteei 0 /* disable interrupts while actually switching */ 378 379 /* indicate new pcb */ 380 lwz 4,L_ADDR(31) 381 lis 5,_C_LABEL(curpcb)@ha 382 stw 4,_C_LABEL(curpcb)@l(5) 383 384 /* save real pmap pointer for spill fill */ 385 lwz 5,PCB_PMR(4) 386 lis 6,_C_LABEL(curpm)@ha 387 stwu 5,_C_LABEL(curpm)@l(6) 388 stwcx. 5,0,6 /* clear possible reservation */ 389 390 /* Switch to the new virtual space */ 391 /* Do not have to do anything here. TLB PID gets updated on return from trap. */ 392 393 lwz 1,PCB_SP(4) /* get new procs SP */ 394 395 wrteei 1 /* interrupts are okay again */ 396 397 lmw 10,8(1) /* get other regs */ 398 lwz 1,0(1) /* get saved SP */ 399 mr 2,12 /* get saved r2 */ 400 mtcr 11 /* get saved cr */ 401 isync 402 403 preempt_return: 404 lwz 3,PCB_SPL(4) 405 bl _C_LABEL(lcsplx) 406 407 0: 408 lis 3,_C_LABEL(curpm)@ha 409 addi 3,3,_C_LABEL(curpm)@l /* Do we need a context? */ 410 lwz 4,PM_CTX(3) 411 cmpwi 4,0 412 # mtspr SPR_SPR0,4 /* Always keep the current ctx here */ 413 mr 3,30 414 bne 1f 415 bl _C_LABEL(ctx_alloc) 416 b 0b /* Reload */ 417 1: 418 lwz 31,16(1) 419 lwz 30,12(1) 420 lwz 29,8(1) 421 addi 1,1,20 422 lwz 0,4(1) 423 mtlr 0 424 blr 425 426 427 /* 428 * Child comes here at the end of a fork. 429 * Return to userspace via the trap return path. 430 */ 431 .globl _C_LABEL(fork_trampoline) 432 _C_LABEL(fork_trampoline): 433 xor 3,3,3 434 bl _C_LABEL(lcsplx) 435 mtlr 31 436 mr 3,30 437 blrl /* jump indirect to r31 */ 438 b trapexit 439 440 /* 441 * Pull in common trap vector code. 442 */ 443 #include <powerpc/ibm4xx/trap_subr.S> 444 #include <powerpc/ibm4xx/4xx_trap_subr.S> 445 446 /* 447 * int setfault() 448 * 449 * Similar to setjmp to setup for handling faults on accesses to user memory. 450 * Any routine using this may only call bcopy, either the form below, 451 * or the (currently used) C code optimized, so it doesn't use any non-volatile 452 * registers. 453 */ 454 .globl _C_LABEL(setfault) 455 _C_LABEL(setfault): 456 mflr 0 457 mfcr 12 458 lis 4,_C_LABEL(curpcb)@ha 459 lwz 4,_C_LABEL(curpcb)@l(4) 460 stw 3,PCB_FAULT(4) 461 stw 0,0(3) 462 stw 1,4(3) 463 stw 2,8(3) 464 stmw 12,12(3) 465 xor 3,3,3 466 blr 467 468 .globl _C_LABEL(ppc4xx_reset) 469 _C_LABEL(ppc4xx_reset): 470 mfspr 3,SPR_DBCR0 471 oris 3,r13,DBCR0_RST_SYSTEM@h 472 mtspr SPR_DBCR0,3 473 ba 0 474 475 #if 0 476 /* 477 * XXXX the following doesn't quite work right yet. 478 */ 479 /* 480 * void bcopy(const void *src, void *dst, size_t len); 481 * 482 * swap r3 and r4 and fall through to memcopy. 483 */ 484 .globl _C_LABEL(bcopy) 485 _C_LABEL(bcopy): 486 mr r0,r3 487 mr r3,r4 488 mr r4,r0 489 /* FALLTHROUGH */ 490 491 /* 492 * void * memcpy(void *dst (r3), const void *src (r4), size_t len (r5)); 493 * 494 * Copy memory (obviously) 495 * 496 * We will try to do data cache block aligned stores so we 497 * can use block allocate and not have to read from the 498 * destination. 499 * 500 * Register use: 501 * 502 * r1 stack (of course) 503 * r3 dst 504 * r4 src 505 * r5 len 506 * r6 tmp 507 * r7 holds 32 508 * r8 holds dst 509 * r24-r31 block move regs 510 * 511 */ 512 513 ENTRY(memcpy) 514 stwu r1,-(10*4)(r1) /* Allocate some RAM to save 8 regs to. */ 515 cmpwi r5, 32 /* Less than 32 bytes ? */ 516 stmw r24,8(r1) /* Save ALL regs (could be optimized) */ 517 518 mr r8,r3 /* save dst */ 519 li r7,32 520 521 dcbt 0,r4 /* Start bringing in cache line. */ 522 blt 1f /* Finish up */ 523 524 neg r6,r3 /* Find how far unaligned we are... */ 525 andi. r6,r6,31 /* Cache-align dest. */ 526 mtxer r6 527 sub r5,r5,r6 /* subtract count */ 528 lswx r24,0,r4 /* Load some. */ 529 add r4,r4,r6 530 dcbt 0,r4 /* Fetch next line */ 531 stswx r24,0,r3 /* Store some */ 532 add r3,r3,r6 533 addic. r6,r5,-32 /* Pre-decrement next line */ 534 ble 1f /* Less than 32-bytes? finishup */ 535 536 /* Dest should not be cache line aligned. */ 537 /* XXX need gas 2.11 to grok dcba insn */ 538 #ifdef GAS_2_11 539 dcba 0,r3 /* Allocate a line */ 540 #else 541 .long 0x7c001dec /* dcba 0,r3 */ 542 #endif 543 0: 544 dcbt r7,r4 /* Bring in the next line, too */ 545 546 lswi r24,r4,32 547 addi r4,r4,32 /* Inc src */ 548 mr r5,r6 549 550 addic. r6,r5,-32 551 stswi r24,r3,32 552 addi r3,r3,32 /* Inc dst */ 553 #ifdef GAS_2_11 554 dcba 0,r3 /* Allocate another line */ 555 #else 556 .long 0x7c071dec /* dcba r7,r3 */ 557 #endif 558 bgt 0b 559 1: 560 mtxer r5 /* Store byte count */ 561 lswx r24,0,r4 /* Load up to 32 bytes */ 562 stswx r24,0,r3 /* Store up to 32 bytes */ 563 564 mr r3,r8 /* Return dst */ 565 566 lmw r24,8(r1) 567 addi r1,r1,(10*4) 568 blr 569 #endif 570
Indexes created Sat Oct 11 19:10:01 GMT 2025