1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz. 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: @(#)isa.c 7.2 (Berkeley) 5/13/91 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 /* 41 * code to manage AT bus 42 * 43 * 92/08/18 Frank P. MacLachlan (fpm@crash.cts.com): 44 * Fixed uninitialized variable problem and added code to deal 45 * with DMA page boundaries in isa_dmarangecheck(). Fixed word 46 * mode DMA count compution and reorganized DMA setup code in 47 * isa_dmastart() 48 */ 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/bus.h> 53 #include <sys/kernel.h> 54 #include <sys/malloc.h> 55 #include <sys/lock.h> 56 #include <sys/proc.h> 57 #include <sys/mutex.h> 58 #include <sys/module.h> 59 #include <vm/vm.h> 60 #include <vm/vm_param.h> 61 #include <vm/pmap.h> 62 #include <isa/isareg.h> 63 #include <isa/isavar.h> 64 #include <isa/isa_dmareg.h> 65 66 #define ISARAM_END 0x1000000 67 68 static int isa_dmarangecheck(caddr_t va, u_int length, int chan); 69 70 static caddr_t dma_bouncebuf[8]; 71 static u_int dma_bouncebufsize[8]; 72 static u_int8_t dma_bounced = 0; 73 static u_int8_t dma_busy = 0; /* Used in isa_dmastart() */ 74 static u_int8_t dma_inuse = 0; /* User for acquire/release */ 75 static u_int8_t dma_auto_mode = 0; 76 static struct mtx isa_dma_lock; 77 MTX_SYSINIT(isa_dma_lock, &isa_dma_lock, "isa DMA lock", MTX_DEF); 78 79 #define VALID_DMA_MASK (7) 80 81 /* high byte of address is stored in this port for i-th dma channel */ 82 static int dmapageport[8] = { 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a }; 83 84 /* 85 * Setup a DMA channel's bounce buffer. 86 */ 87 int 88 isa_dma_init(int chan, u_int bouncebufsize, int flag) 89 { 90 void *buf; 91 int contig; 92 93 #ifdef DIAGNOSTIC 94 if (chan & ~VALID_DMA_MASK) 95 panic("isa_dma_init: channel out of range"); 96 #endif 97 98 99 /* Try malloc() first. It works better if it works. */ 100 buf = malloc(bouncebufsize, M_DEVBUF, flag); 101 if (buf != NULL) { 102 if (isa_dmarangecheck(buf, bouncebufsize, chan) != 0) { 103 free(buf, M_DEVBUF); 104 buf = NULL; 105 } 106 contig = 0; 107 } 108 109 if (buf == NULL) { 110 buf = contigmalloc(bouncebufsize, M_DEVBUF, flag, 0ul, 0xfffffful, 111 1ul, chan & 4 ? 0x20000ul : 0x10000ul); 112 contig = 1; 113 } 114 115 if (buf == NULL) 116 return (ENOMEM); 117 118 mtx_lock(&isa_dma_lock); 119 /* 120 * If a DMA channel is shared, both drivers have to call isa_dma_init 121 * since they don't know that the other driver will do it. 122 * Just return if we're already set up good. 123 * XXX: this only works if they agree on the bouncebuf size. This 124 * XXX: is typically the case since they are multiple instances of 125 * XXX: the same driver. 126 */ 127 if (dma_bouncebuf[chan] != NULL) { 128 if (contig) 129 contigfree(buf, bouncebufsize, M_DEVBUF); 130 else 131 free(buf, M_DEVBUF); 132 mtx_unlock(&isa_dma_lock); 133 return (0); 134 } 135 136 dma_bouncebufsize[chan] = bouncebufsize; 137 dma_bouncebuf[chan] = buf; 138 139 mtx_unlock(&isa_dma_lock); 140 141 return (0); 142 } 143 144 /* 145 * Register a DMA channel's usage. Usually called from a device driver 146 * in open() or during its initialization. 147 */ 148 int 149 isa_dma_acquire(chan) 150 int chan; 151 { 152 #ifdef DIAGNOSTIC 153 if (chan & ~VALID_DMA_MASK) 154 panic("isa_dma_acquire: channel out of range"); 155 #endif 156 157 mtx_lock(&isa_dma_lock); 158 if (dma_inuse & (1 << chan)) { 159 printf("isa_dma_acquire: channel %d already in use\n", chan); 160 mtx_unlock(&isa_dma_lock); 161 return (EBUSY); 162 } 163 dma_inuse |= (1 << chan); 164 dma_auto_mode &= ~(1 << chan); 165 mtx_unlock(&isa_dma_lock); 166 167 return (0); 168 } 169 170 /* 171 * Unregister a DMA channel's usage. Usually called from a device driver 172 * during close() or during its shutdown. 173 */ 174 void 175 isa_dma_release(chan) 176 int chan; 177 { 178 #ifdef DIAGNOSTIC 179 if (chan & ~VALID_DMA_MASK) 180 panic("isa_dma_release: channel out of range"); 181 182 mtx_lock(&isa_dma_lock); 183 if ((dma_inuse & (1 << chan)) == 0) 184 printf("isa_dma_release: channel %d not in use\n", chan); 185 #else 186 mtx_lock(&isa_dma_lock); 187 #endif 188 189 if (dma_busy & (1 << chan)) { 190 dma_busy &= ~(1 << chan); 191 /* 192 * XXX We should also do "dma_bounced &= (1 << chan);" 193 * because we are acting on behalf of isa_dmadone() which 194 * was not called to end the last DMA operation. This does 195 * not matter now, but it may in the future. 196 */ 197 } 198 199 dma_inuse &= ~(1 << chan); 200 dma_auto_mode &= ~(1 << chan); 201 202 mtx_unlock(&isa_dma_lock); 203 } 204 205 /* 206 * isa_dmacascade(): program 8237 DMA controller channel to accept 207 * external dma control by a board. 208 */ 209 void 210 isa_dmacascade(chan) 211 int chan; 212 { 213 #ifdef DIAGNOSTIC 214 if (chan & ~VALID_DMA_MASK) 215 panic("isa_dmacascade: channel out of range"); 216 #endif 217 218 mtx_lock(&isa_dma_lock); 219 /* set dma channel mode, and set dma channel mode */ 220 if ((chan & 4) == 0) { 221 outb(DMA1_MODE, DMA37MD_CASCADE | chan); 222 outb(DMA1_SMSK, chan); 223 } else { 224 outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3)); 225 outb(DMA2_SMSK, chan & 3); 226 } 227 mtx_unlock(&isa_dma_lock); 228 } 229 230 /* 231 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment 232 * problems by using a bounce buffer. 233 */ 234 void 235 isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan) 236 { 237 vm_paddr_t phys; 238 int waport; 239 caddr_t newaddr; 240 int dma_range_checked; 241 242 dma_range_checked = isa_dmarangecheck(addr, nbytes, chan); 243 244 #ifdef DIAGNOSTIC 245 if (chan & ~VALID_DMA_MASK) 246 panic("isa_dmastart: channel out of range"); 247 248 if ((chan < 4 && nbytes > (1<<16)) 249 || (chan >= 4 && (nbytes > (1<<17) || (uintptr_t)addr & 1))) 250 panic("isa_dmastart: impossible request"); 251 252 mtx_lock(&isa_dma_lock); 253 if ((dma_inuse & (1 << chan)) == 0) 254 printf("isa_dmastart: channel %d not acquired\n", chan); 255 #else 256 mtx_lock(&isa_dma_lock); 257 #endif 258 259 #if 0 260 /* 261 * XXX This should be checked, but drivers like ad1848 only call 262 * isa_dmastart() once because they use Auto DMA mode. If we 263 * leave this in, drivers that do this will print this continuously. 264 */ 265 if (dma_busy & (1 << chan)) 266 printf("isa_dmastart: channel %d busy\n", chan); 267 #endif 268 269 dma_busy |= (1 << chan); 270 271 if (dma_range_checked) { 272 if (dma_bouncebuf[chan] == NULL 273 || dma_bouncebufsize[chan] < nbytes) 274 panic("isa_dmastart: bad bounce buffer"); 275 dma_bounced |= (1 << chan); 276 newaddr = dma_bouncebuf[chan]; 277 278 /* copy bounce buffer on write */ 279 if (!(flags & ISADMA_READ)) 280 bcopy(addr, newaddr, nbytes); 281 addr = newaddr; 282 } 283 284 /* translate to physical */ 285 phys = pmap_extract(kernel_pmap, (vm_offset_t)addr); 286 287 if (flags & ISADMA_RAW) { 288 dma_auto_mode |= (1 << chan); 289 } else { 290 dma_auto_mode &= ~(1 << chan); 291 } 292 293 if ((chan & 4) == 0) { 294 /* 295 * Program one of DMA channels 0..3. These are 296 * byte mode channels. 297 */ 298 /* set dma channel mode, and reset address ff */ 299 300 /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 301 if (flags & ISADMA_RAW) { 302 if (flags & ISADMA_READ) 303 outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan); 304 else 305 outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan); 306 } 307 else 308 if (flags & ISADMA_READ) 309 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan); 310 else 311 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan); 312 outb(DMA1_FFC, 0); 313 314 /* send start address */ 315 waport = DMA1_CHN(chan); 316 outb(waport, phys); 317 outb(waport, phys>>8); 318 outb(dmapageport[chan], phys>>16); 319 320 /* send count */ 321 outb(waport + 1, --nbytes); 322 outb(waport + 1, nbytes>>8); 323 324 /* unmask channel */ 325 outb(DMA1_SMSK, chan); 326 } else { 327 /* 328 * Program one of DMA channels 4..7. These are 329 * word mode channels. 330 */ 331 /* set dma channel mode, and reset address ff */ 332 333 /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 334 if (flags & ISADMA_RAW) { 335 if (flags & ISADMA_READ) 336 outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3)); 337 else 338 outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3)); 339 } 340 else 341 if (flags & ISADMA_READ) 342 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3)); 343 else 344 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3)); 345 outb(DMA2_FFC, 0); 346 347 /* send start address */ 348 waport = DMA2_CHN(chan - 4); 349 outb(waport, phys>>1); 350 outb(waport, phys>>9); 351 outb(dmapageport[chan], phys>>16); 352 353 /* send count */ 354 nbytes >>= 1; 355 outb(waport + 2, --nbytes); 356 outb(waport + 2, nbytes>>8); 357 358 /* unmask channel */ 359 outb(DMA2_SMSK, chan & 3); 360 } 361 mtx_unlock(&isa_dma_lock); 362 } 363 364 void 365 isa_dmadone(int flags, caddr_t addr, int nbytes, int chan) 366 { 367 #ifdef DIAGNOSTIC 368 if (chan & ~VALID_DMA_MASK) 369 panic("isa_dmadone: channel out of range"); 370 371 if ((dma_inuse & (1 << chan)) == 0) 372 printf("isa_dmadone: channel %d not acquired\n", chan); 373 #endif 374 375 mtx_lock(&isa_dma_lock); 376 if (((dma_busy & (1 << chan)) == 0) && 377 (dma_auto_mode & (1 << chan)) == 0 ) 378 printf("isa_dmadone: channel %d not busy\n", chan); 379 380 if ((dma_auto_mode & (1 << chan)) == 0) 381 outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4); 382 383 if (dma_bounced & (1 << chan)) { 384 /* copy bounce buffer on read */ 385 if (flags & ISADMA_READ) 386 bcopy(dma_bouncebuf[chan], addr, nbytes); 387 388 dma_bounced &= ~(1 << chan); 389 } 390 dma_busy &= ~(1 << chan); 391 mtx_unlock(&isa_dma_lock); 392 } 393 394 /* 395 * Check for problems with the address range of a DMA transfer 396 * (non-contiguous physical pages, outside of bus address space, 397 * crossing DMA page boundaries). 398 * Return true if special handling needed. 399 */ 400 401 static int 402 isa_dmarangecheck(caddr_t va, u_int length, int chan) 403 { 404 vm_paddr_t phys, priorpage = 0; 405 vm_offset_t endva; 406 u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1); 407 408 endva = (vm_offset_t)round_page((vm_offset_t)va + length); 409 for (; va < (caddr_t) endva ; va += PAGE_SIZE) { 410 phys = trunc_page(pmap_extract(kernel_pmap, (vm_offset_t)va)); 411 if (phys == 0) 412 panic("isa_dmacheck: no physical page present"); 413 if (phys >= ISARAM_END) 414 return (1); 415 if (priorpage) { 416 if (priorpage + PAGE_SIZE != phys) 417 return (1); 418 /* check if crossing a DMA page boundary */ 419 if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk) 420 return (1); 421 } 422 priorpage = phys; 423 } 424 return (0); 425 } 426 427 /* 428 * Query the progress of a transfer on a DMA channel. 429 * 430 * To avoid having to interrupt a transfer in progress, we sample 431 * each of the high and low databytes twice, and apply the following 432 * logic to determine the correct count. 433 * 434 * Reads are performed with interrupts disabled, thus it is to be 435 * expected that the time between reads is very small. At most 436 * one rollover in the low count byte can be expected within the 437 * four reads that are performed. 438 * 439 * There are three gaps in which a rollover can occur : 440 * 441 * - read low1 442 * gap1 443 * - read high1 444 * gap2 445 * - read low2 446 * gap3 447 * - read high2 448 * 449 * If a rollover occurs in gap1 or gap2, the low2 value will be 450 * greater than the low1 value. In this case, low2 and high2 are a 451 * corresponding pair. 452 * 453 * In any other case, low1 and high1 can be considered to be correct. 454 * 455 * The function returns the number of bytes remaining in the transfer, 456 * or -1 if the channel requested is not active. 457 * 458 */ 459 static int 460 isa_dmastatus_locked(int chan) 461 { 462 u_long cnt = 0; 463 int ffport, waport; 464 u_long low1, high1, low2, high2; 465 466 mtx_assert(&isa_dma_lock, MA_OWNED); 467 468 /* channel active? */ 469 if ((dma_inuse & (1 << chan)) == 0) { 470 printf("isa_dmastatus: channel %d not active\n", chan); 471 return(-1); 472 } 473 /* channel busy? */ 474 475 if (((dma_busy & (1 << chan)) == 0) && 476 (dma_auto_mode & (1 << chan)) == 0 ) { 477 printf("chan %d not busy\n", chan); 478 return -2 ; 479 } 480 if (chan < 4) { /* low DMA controller */ 481 ffport = DMA1_FFC; 482 waport = DMA1_CHN(chan) + 1; 483 } else { /* high DMA controller */ 484 ffport = DMA2_FFC; 485 waport = DMA2_CHN(chan - 4) + 2; 486 } 487 488 disable_intr(); /* no interrupts Mr Jones! */ 489 outb(ffport, 0); /* clear register LSB flipflop */ 490 low1 = inb(waport); 491 high1 = inb(waport); 492 outb(ffport, 0); /* clear again */ 493 low2 = inb(waport); 494 high2 = inb(waport); 495 enable_intr(); /* enable interrupts again */ 496 497 /* 498 * Now decide if a wrap has tried to skew our results. 499 * Note that after TC, the count will read 0xffff, while we want 500 * to return zero, so we add and then mask to compensate. 501 */ 502 if (low1 >= low2) { 503 cnt = (low1 + (high1 << 8) + 1) & 0xffff; 504 } else { 505 cnt = (low2 + (high2 << 8) + 1) & 0xffff; 506 } 507 508 if (chan >= 4) /* high channels move words */ 509 cnt *= 2; 510 return(cnt); 511 } 512 513 int 514 isa_dmastatus(int chan) 515 { 516 int status; 517 518 mtx_lock(&isa_dma_lock); 519 status = isa_dmastatus_locked(chan); 520 mtx_unlock(&isa_dma_lock); 521 522 return (status); 523 } 524 525 /* 526 * Reached terminal count yet ? 527 */ 528 int 529 isa_dmatc(int chan) 530 { 531 532 if (chan < 4) 533 return(inb(DMA1_STATUS) & (1 << chan)); 534 else 535 return(inb(DMA2_STATUS) & (1 << (chan & 3))); 536 } 537 538 /* 539 * Stop a DMA transfer currently in progress. 540 */ 541 int 542 isa_dmastop(int chan) 543 { 544 int status; 545 546 mtx_lock(&isa_dma_lock); 547 if ((dma_inuse & (1 << chan)) == 0) 548 printf("isa_dmastop: channel %d not acquired\n", chan); 549 550 if (((dma_busy & (1 << chan)) == 0) && 551 ((dma_auto_mode & (1 << chan)) == 0)) { 552 printf("chan %d not busy\n", chan); 553 mtx_unlock(&isa_dma_lock); 554 return -2 ; 555 } 556 557 if ((chan & 4) == 0) { 558 outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */); 559 } else { 560 outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */); 561 } 562 563 status = isa_dmastatus_locked(chan); 564 565 mtx_unlock(&isa_dma_lock); 566 567 return (status); 568 } 569 570 /* 571 * Attach to the ISA PnP descriptor for the AT DMA controller 572 */ 573 static struct isa_pnp_id atdma_ids[] = { 574 { 0x0002d041 /* PNP0200 */, "AT DMA controller" }, 575 { 0 } 576 }; 577 578 static int 579 atdma_probe(device_t dev) 580 { 581 int result; 582 583 if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0) 584 device_quiet(dev); 585 return(result); 586 } 587 588 static int 589 atdma_attach(device_t dev) 590 { 591 return(0); 592 } 593 594 static device_method_t atdma_methods[] = { 595 /* Device interface */ 596 DEVMETHOD(device_probe, atdma_probe), 597 DEVMETHOD(device_attach, atdma_attach), 598 DEVMETHOD(device_detach, bus_generic_detach), 599 DEVMETHOD(device_shutdown, bus_generic_shutdown), 600 DEVMETHOD(device_suspend, bus_generic_suspend), 601 DEVMETHOD(device_resume, bus_generic_resume), 602 { 0, 0 } 603 }; 604 605 static driver_t atdma_driver = { 606 "atdma", 607 atdma_methods, 608 1, /* no softc */ 609 }; 610 611 static devclass_t atdma_devclass; 612 613 DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0); 614 DRIVER_MODULE(atdma, acpi, atdma_driver, atdma_devclass, 0, 0); 615 ISA_PNP_INFO(atdma_ids); 616