dma.c revision 1.26
1 /* $NetBSD: dma.c,v 1.26 2002/03/15 05:55:35 gmcgarry Exp $ */ 2 3 /*- 4 * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * Copyright (c) 1982, 1990, 1993 41 * The Regents of the University of California. 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 the University of 54 * California, Berkeley and its contributors. 55 * 4. Neither the name of the University nor the names of its contributors 56 * may be used to endorse or promote products derived from this software 57 * without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * @(#)dma.c 8.1 (Berkeley) 6/10/93 72 */ 73 74 /* 75 * DMA driver 76 */ 77 78 #include <sys/cdefs.h> 79 __KERNEL_RCSID(0, "$NetBSD: dma.c,v 1.26 2002/03/15 05:55:35 gmcgarry Exp $"); 80 81 #include <machine/hp300spu.h> /* XXX param.h includes cpu.h */ 82 83 #include <sys/param.h> 84 #include <sys/systm.h> 85 #include <sys/callout.h> 86 #include <sys/time.h> 87 #include <sys/kernel.h> 88 #include <sys/proc.h> 89 #include <sys/device.h> 90 91 #include <machine/frame.h> 92 #include <machine/cpu.h> 93 #include <machine/intr.h> 94 95 #include <hp300/dev/dmareg.h> 96 #include <hp300/dev/dmavar.h> 97 98 /* 99 * The largest single request will be MAXPHYS bytes which will require 100 * at most MAXPHYS/NBPG+1 chain elements to describe, i.e. if none of 101 * the buffer pages are physically contiguous (MAXPHYS/NBPG) and the 102 * buffer is not page aligned (+1). 103 */ 104 #define DMAMAXIO (MAXPHYS/NBPG+1) 105 106 struct dma_chain { 107 int dc_count; 108 char *dc_addr; 109 }; 110 111 struct dma_channel { 112 struct dmaqueue *dm_job; /* current job */ 113 struct dmadevice *dm_hwaddr; /* registers if DMA_C */ 114 struct dmaBdevice *dm_Bhwaddr; /* registers if not DMA_C */ 115 char dm_flags; /* misc. flags */ 116 u_short dm_cmd; /* DMA controller command */ 117 int dm_cur; /* current segment */ 118 int dm_last; /* last segment */ 119 struct dma_chain dm_chain[DMAMAXIO]; /* all segments */ 120 }; 121 122 struct dma_softc { 123 struct dmareg *sc_dmareg; /* pointer to our hardware */ 124 struct dma_channel sc_chan[NDMACHAN]; /* 2 channels */ 125 TAILQ_HEAD(, dmaqueue) sc_queue; /* job queue */ 126 struct callout sc_debug_ch; 127 char sc_type; /* A, B, or C */ 128 int sc_ipl; /* our interrupt level */ 129 void *sc_ih; /* interrupt cookie */ 130 } dma_softc; 131 132 /* types */ 133 #define DMA_B 0 134 #define DMA_C 1 135 136 /* flags */ 137 #define DMAF_PCFLUSH 0x01 138 #define DMAF_VCFLUSH 0x02 139 #define DMAF_NOINTR 0x04 140 141 int dmaintr __P((void *)); 142 143 #ifdef DEBUG 144 int dmadebug = 0; 145 #define DDB_WORD 0x01 /* same as DMAGO_WORD */ 146 #define DDB_LWORD 0x02 /* same as DMAGO_LWORD */ 147 #define DDB_FOLLOW 0x04 148 #define DDB_IO 0x08 149 150 void dmatimeout __P((void *)); 151 int dmatimo[NDMACHAN]; 152 153 long dmahits[NDMACHAN]; 154 long dmamisses[NDMACHAN]; 155 long dmabyte[NDMACHAN]; 156 long dmaword[NDMACHAN]; 157 long dmalword[NDMACHAN]; 158 #endif 159 160 /* 161 * Initialize the DMA engine, called by dioattach() 162 */ 163 void 164 dmainit() 165 { 166 struct dma_softc *sc = &dma_softc; 167 struct dmareg *dma; 168 struct dma_channel *dc; 169 int i; 170 char rev; 171 172 /* There's just one. */ 173 sc->sc_dmareg = (struct dmareg *)DMA_BASE; 174 dma = sc->sc_dmareg; 175 176 /* 177 * Determine the DMA type. A DMA_A or DMA_B will fail the 178 * following probe. 179 * 180 * XXX Don't know how to easily differentiate the A and B cards, 181 * so we just hope nobody has an A card (A cards will work if 182 * splbio works out to ipl 3). 183 */ 184 if (badbaddr((char *)&dma->dma_id[2])) { 185 rev = 'B'; 186 #if !defined(HP320) 187 panic("dmainit: DMA card requires hp320 support"); 188 #endif 189 } else 190 rev = dma->dma_id[2]; 191 192 sc->sc_type = (rev == 'B') ? DMA_B : DMA_C; 193 194 TAILQ_INIT(&sc->sc_queue); 195 callout_init(&sc->sc_debug_ch); 196 197 for (i = 0; i < NDMACHAN; i++) { 198 dc = &sc->sc_chan[i]; 199 dc->dm_job = NULL; 200 switch (i) { 201 case 0: 202 dc->dm_hwaddr = &dma->dma_chan0; 203 dc->dm_Bhwaddr = &dma->dma_Bchan0; 204 break; 205 206 case 1: 207 dc->dm_hwaddr = &dma->dma_chan1; 208 dc->dm_Bhwaddr = &dma->dma_Bchan1; 209 break; 210 211 default: 212 panic("dmainit: more than 2 channels?"); 213 /* NOTREACHED */ 214 } 215 } 216 217 #ifdef DEBUG 218 /* make sure timeout is really not needed */ 219 callout_reset(&sc->sc_debug_ch, 30 * hz, dmatimeout, sc); 220 #endif 221 222 printf("98620%c, 2 channels, %d bit DMA\n", 223 rev, (rev == 'B') ? 16 : 32); 224 225 /* 226 * Defer hooking up our interrupt until the first 227 * DMA-using controller has hooked up theirs. 228 */ 229 sc->sc_ih = NULL; 230 } 231 232 /* 233 * Compute the ipl and (re)establish the interrupt handler 234 * for the DMA controller. 235 */ 236 void 237 dmacomputeipl() 238 { 239 struct dma_softc *sc = &dma_softc; 240 241 if (sc->sc_ih != NULL) 242 intr_disestablish(sc->sc_ih); 243 244 /* 245 * Our interrupt level must be as high as the highest 246 * device using DMA (i.e. splbio). 247 */ 248 sc->sc_ipl = PSLTOIPL(hp300_ipls[HP300_IPL_BIO]); 249 sc->sc_ih = intr_establish(dmaintr, sc, sc->sc_ipl, IPL_BIO); 250 } 251 252 int 253 dmareq(dq) 254 struct dmaqueue *dq; 255 { 256 struct dma_softc *sc = &dma_softc; 257 int i, chan, s; 258 259 #if 1 260 s = splhigh(); /* XXXthorpej */ 261 #else 262 s = splbio(); 263 #endif 264 265 chan = dq->dq_chan; 266 for (i = NDMACHAN - 1; i >= 0; i--) { 267 /* 268 * Can we use this channel? 269 */ 270 if ((chan & (1 << i)) == 0) 271 continue; 272 273 /* 274 * We can use it; is it busy? 275 */ 276 if (sc->sc_chan[i].dm_job != NULL) 277 continue; 278 279 /* 280 * Not busy; give the caller this channel. 281 */ 282 sc->sc_chan[i].dm_job = dq; 283 dq->dq_chan = i; 284 splx(s); 285 return (1); 286 } 287 288 /* 289 * Couldn't get a channel now; put this in the queue. 290 */ 291 TAILQ_INSERT_TAIL(&sc->sc_queue, dq, dq_list); 292 splx(s); 293 return (0); 294 } 295 296 void 297 dmafree(dq) 298 struct dmaqueue *dq; 299 { 300 int unit = dq->dq_chan; 301 struct dma_softc *sc = &dma_softc; 302 struct dma_channel *dc = &sc->sc_chan[unit]; 303 struct dmaqueue *dn; 304 int chan, s; 305 306 #if 1 307 s = splhigh(); /* XXXthorpej */ 308 #else 309 s = splbio(); 310 #endif 311 312 #ifdef DEBUG 313 dmatimo[unit] = 0; 314 #endif 315 316 DMA_CLEAR(dc); 317 318 #if defined(CACHE_HAVE_PAC) || defined(M68040) 319 /* 320 * XXX we may not always go thru the flush code in dmastop() 321 */ 322 if (dc->dm_flags & DMAF_PCFLUSH) { 323 PCIA(); 324 dc->dm_flags &= ~DMAF_PCFLUSH; 325 } 326 #endif 327 328 #if defined(CACHE_HAVE_VAC) 329 if (dc->dm_flags & DMAF_VCFLUSH) { 330 /* 331 * 320/350s have VACs that may also need flushing. 332 * In our case we only flush the supervisor side 333 * because we know that if we are DMAing to user 334 * space, the physical pages will also be mapped 335 * in kernel space (via vmapbuf) and hence cache- 336 * inhibited by the pmap module due to the multiple 337 * mapping. 338 */ 339 DCIS(); 340 dc->dm_flags &= ~DMAF_VCFLUSH; 341 } 342 #endif 343 344 /* 345 * Channel is now free. Look for another job to run on this 346 * channel. 347 */ 348 dc->dm_job = NULL; 349 chan = 1 << unit; 350 for (dn = sc->sc_queue.tqh_first; dn != NULL; 351 dn = dn->dq_list.tqe_next) { 352 if (dn->dq_chan & chan) { 353 /* Found one... */ 354 TAILQ_REMOVE(&sc->sc_queue, dn, dq_list); 355 dc->dm_job = dn; 356 dn->dq_chan = dq->dq_chan; 357 splx(s); 358 359 /* Start the initiator. */ 360 (*dn->dq_start)(dn->dq_softc); 361 return; 362 } 363 } 364 splx(s); 365 } 366 367 void 368 dmago(unit, addr, count, flags) 369 int unit; 370 char *addr; 371 int count; 372 int flags; 373 { 374 struct dma_softc *sc = &dma_softc; 375 struct dma_channel *dc = &sc->sc_chan[unit]; 376 char *dmaend = NULL; 377 int seg, tcount; 378 379 if (count > MAXPHYS) 380 panic("dmago: count > MAXPHYS"); 381 382 #if defined(HP320) 383 if (sc->sc_type == DMA_B && (flags & DMAGO_LWORD)) 384 panic("dmago: no can do 32-bit DMA"); 385 #endif 386 387 #ifdef DEBUG 388 if (dmadebug & DDB_FOLLOW) 389 printf("dmago(%d, %p, %x, %x)\n", 390 unit, addr, count, flags); 391 if (flags & DMAGO_LWORD) 392 dmalword[unit]++; 393 else if (flags & DMAGO_WORD) 394 dmaword[unit]++; 395 else 396 dmabyte[unit]++; 397 #endif 398 /* 399 * Build the DMA chain 400 */ 401 for (seg = 0; count > 0; seg++) { 402 dc->dm_chain[seg].dc_addr = (char *) kvtop(addr); 403 #if defined(M68040) 404 /* 405 * Push back dirty cache lines 406 */ 407 if (mmutype == MMU_68040) 408 DCFP((paddr_t)dc->dm_chain[seg].dc_addr); 409 #endif 410 if (count < (tcount = NBPG - ((int)addr & PGOFSET))) 411 tcount = count; 412 dc->dm_chain[seg].dc_count = tcount; 413 addr += tcount; 414 count -= tcount; 415 if (flags & DMAGO_LWORD) 416 tcount >>= 2; 417 else if (flags & DMAGO_WORD) 418 tcount >>= 1; 419 420 /* 421 * Try to compact the DMA transfer if the pages are adjacent. 422 * Note: this will never happen on the first iteration. 423 */ 424 if (dc->dm_chain[seg].dc_addr == dmaend 425 #if defined(HP320) 426 /* only 16-bit count on 98620B */ 427 && (sc->sc_type != DMA_B || 428 dc->dm_chain[seg - 1].dc_count + tcount <= 65536) 429 #endif 430 ) { 431 #ifdef DEBUG 432 dmahits[unit]++; 433 #endif 434 dmaend += dc->dm_chain[seg].dc_count; 435 dc->dm_chain[--seg].dc_count += tcount; 436 } else { 437 #ifdef DEBUG 438 dmamisses[unit]++; 439 #endif 440 dmaend = dc->dm_chain[seg].dc_addr + 441 dc->dm_chain[seg].dc_count; 442 dc->dm_chain[seg].dc_count = tcount; 443 } 444 } 445 dc->dm_cur = 0; 446 dc->dm_last = --seg; 447 dc->dm_flags = 0; 448 /* 449 * Set up the command word based on flags 450 */ 451 dc->dm_cmd = DMA_ENAB | DMA_IPL(sc->sc_ipl) | DMA_START; 452 if ((flags & DMAGO_READ) == 0) 453 dc->dm_cmd |= DMA_WRT; 454 if (flags & DMAGO_LWORD) 455 dc->dm_cmd |= DMA_LWORD; 456 else if (flags & DMAGO_WORD) 457 dc->dm_cmd |= DMA_WORD; 458 if (flags & DMAGO_PRI) 459 dc->dm_cmd |= DMA_PRI; 460 461 #if defined(M68040) 462 /* 463 * On the 68040 we need to flush (push) the data cache before a 464 * DMA (already done above) and flush again after DMA completes. 465 * In theory we should only need to flush prior to a write DMA 466 * and purge after a read DMA but if the entire page is not 467 * involved in the DMA we might purge some valid data. 468 */ 469 if (mmutype == MMU_68040 && (flags & DMAGO_READ)) 470 dc->dm_flags |= DMAF_PCFLUSH; 471 #endif 472 473 #if defined(CACHE_HAVE_PAC) 474 /* 475 * Remember if we need to flush external physical cache when 476 * DMA is done. We only do this if we are reading (writing memory). 477 */ 478 if (ectype == EC_PHYS && (flags & DMAGO_READ)) 479 dc->dm_flags |= DMAF_PCFLUSH; 480 #endif 481 482 #if defined(CACHE_HAVE_VAC) 483 if (ectype == EC_VIRT && (flags & DMAGO_READ)) 484 dc->dm_flags |= DMAF_VCFLUSH; 485 #endif 486 487 /* 488 * Remember if we can skip the dma completion interrupt on 489 * the last segment in the chain. 490 */ 491 if (flags & DMAGO_NOINT) { 492 if (dc->dm_cur == dc->dm_last) 493 dc->dm_cmd &= ~DMA_ENAB; 494 else 495 dc->dm_flags |= DMAF_NOINTR; 496 } 497 #ifdef DEBUG 498 if (dmadebug & DDB_IO) { 499 if (((dmadebug&DDB_WORD) && (dc->dm_cmd&DMA_WORD)) || 500 ((dmadebug&DDB_LWORD) && (dc->dm_cmd&DMA_LWORD))) { 501 printf("dmago: cmd %x, flags %x\n", 502 dc->dm_cmd, dc->dm_flags); 503 for (seg = 0; seg <= dc->dm_last; seg++) 504 printf(" %d: %d@%p\n", seg, 505 dc->dm_chain[seg].dc_count, 506 dc->dm_chain[seg].dc_addr); 507 } 508 } 509 dmatimo[unit] = 1; 510 #endif 511 DMA_ARM(sc, dc); 512 } 513 514 void 515 dmastop(unit) 516 int unit; 517 { 518 struct dma_softc *sc = &dma_softc; 519 struct dma_channel *dc = &sc->sc_chan[unit]; 520 521 #ifdef DEBUG 522 if (dmadebug & DDB_FOLLOW) 523 printf("dmastop(%d)\n", unit); 524 dmatimo[unit] = 0; 525 #endif 526 DMA_CLEAR(dc); 527 528 #if defined(CACHE_HAVE_PAC) || defined(M68040) 529 if (dc->dm_flags & DMAF_PCFLUSH) { 530 PCIA(); 531 dc->dm_flags &= ~DMAF_PCFLUSH; 532 } 533 #endif 534 535 #if defined(CACHE_HAVE_VAC) 536 if (dc->dm_flags & DMAF_VCFLUSH) { 537 /* 538 * 320/350s have VACs that may also need flushing. 539 * In our case we only flush the supervisor side 540 * because we know that if we are DMAing to user 541 * space, the physical pages will also be mapped 542 * in kernel space (via vmapbuf) and hence cache- 543 * inhibited by the pmap module due to the multiple 544 * mapping. 545 */ 546 DCIS(); 547 dc->dm_flags &= ~DMAF_VCFLUSH; 548 } 549 #endif 550 551 /* 552 * We may get this interrupt after a device service routine 553 * has freed the dma channel. So, ignore the intr if there's 554 * nothing on the queue. 555 */ 556 if (dc->dm_job != NULL) 557 (*dc->dm_job->dq_done)(dc->dm_job->dq_softc); 558 } 559 560 int 561 dmaintr(arg) 562 void *arg; 563 { 564 struct dma_softc *sc = arg; 565 struct dma_channel *dc; 566 int i, stat; 567 int found = 0; 568 569 #ifdef DEBUG 570 if (dmadebug & DDB_FOLLOW) 571 printf("dmaintr\n"); 572 #endif 573 for (i = 0; i < NDMACHAN; i++) { 574 dc = &sc->sc_chan[i]; 575 stat = DMA_STAT(dc); 576 if ((stat & DMA_INTR) == 0) 577 continue; 578 found++; 579 #ifdef DEBUG 580 if (dmadebug & DDB_IO) { 581 if (((dmadebug&DDB_WORD) && (dc->dm_cmd&DMA_WORD)) || 582 ((dmadebug&DDB_LWORD) && (dc->dm_cmd&DMA_LWORD))) 583 printf("dmaintr: flags %x unit %d stat %x next %d\n", 584 dc->dm_flags, i, stat, dc->dm_cur + 1); 585 } 586 if (stat & DMA_ARMED) 587 printf("dma channel %d: intr when armed\n", i); 588 #endif 589 /* 590 * Load the next segemnt, or finish up if we're done. 591 */ 592 dc->dm_cur++; 593 if (dc->dm_cur <= dc->dm_last) { 594 #ifdef DEBUG 595 dmatimo[i] = 1; 596 #endif 597 /* 598 * If we're the last segment, disable the 599 * completion interrupt, if necessary. 600 */ 601 if (dc->dm_cur == dc->dm_last && 602 (dc->dm_flags & DMAF_NOINTR)) 603 dc->dm_cmd &= ~DMA_ENAB; 604 DMA_CLEAR(dc); 605 DMA_ARM(sc, dc); 606 } else 607 dmastop(i); 608 } 609 return(found); 610 } 611 612 #ifdef DEBUG 613 void 614 dmatimeout(arg) 615 void *arg; 616 { 617 int i, s; 618 struct dma_softc *sc = arg; 619 620 for (i = 0; i < NDMACHAN; i++) { 621 s = splbio(); 622 if (dmatimo[i]) { 623 if (dmatimo[i] > 1) 624 printf("dma channel %d timeout #%d\n", 625 i, dmatimo[i]-1); 626 dmatimo[i]++; 627 } 628 splx(s); 629 } 630 callout_reset(&sc->sc_debug_ch, 30 * hz, dmatimeout, sc); 631 } 632 #endif 633
Indexes created Tue Oct 14 08:09:56 GMT 2025