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(int chan) 150 { 151 #ifdef DIAGNOSTIC 152 if (chan & ~VALID_DMA_MASK) 153 panic("isa_dma_acquire: channel out of range"); 154 #endif 155 156 mtx_lock(&isa_dma_lock); 157 if (dma_inuse & (1 << chan)) { 158 printf("isa_dma_acquire: channel %d already in use\n", chan); 159 mtx_unlock(&isa_dma_lock); 160 return (EBUSY); 161 } 162 dma_inuse |= (1 << chan); 163 dma_auto_mode &= ~(1 << chan); 164 mtx_unlock(&isa_dma_lock); 165 166 return (0); 167 } 168 169 /* 170 * Unregister a DMA channel's usage. Usually called from a device driver 171 * during close() or during its shutdown. 172 */ 173 void 174 isa_dma_release(int chan) 175 { 176 #ifdef DIAGNOSTIC 177 if (chan & ~VALID_DMA_MASK) 178 panic("isa_dma_release: channel out of range"); 179 180 mtx_lock(&isa_dma_lock); 181 if ((dma_inuse & (1 << chan)) == 0) 182 printf("isa_dma_release: channel %d not in use\n", chan); 183 #else 184 mtx_lock(&isa_dma_lock); 185 #endif 186 187 if (dma_busy & (1 << chan)) { 188 dma_busy &= ~(1 << chan); 189 /* 190 * XXX We should also do "dma_bounced &= (1 << chan);" 191 * because we are acting on behalf of isa_dmadone() which 192 * was not called to end the last DMA operation. This does 193 * not matter now, but it may in the future. 194 */ 195 } 196 197 dma_inuse &= ~(1 << chan); 198 dma_auto_mode &= ~(1 << chan); 199 200 mtx_unlock(&isa_dma_lock); 201 } 202 203 /* 204 * isa_dmacascade(): program 8237 DMA controller channel to accept 205 * external dma control by a board. 206 */ 207 void 208 isa_dmacascade(int chan) 209 { 210 #ifdef DIAGNOSTIC 211 if (chan & ~VALID_DMA_MASK) 212 panic("isa_dmacascade: channel out of range"); 213 #endif 214 215 mtx_lock(&isa_dma_lock); 216 /* set dma channel mode, and set dma channel mode */ 217 if ((chan & 4) == 0) { 218 outb(DMA1_MODE, DMA37MD_CASCADE | chan); 219 outb(DMA1_SMSK, chan); 220 } else { 221 outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3)); 222 outb(DMA2_SMSK, chan & 3); 223 } 224 mtx_unlock(&isa_dma_lock); 225 } 226 227 /* 228 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment 229 * problems by using a bounce buffer. 230 */ 231 void 232 isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan) 233 { 234 vm_paddr_t phys; 235 int waport; 236 caddr_t newaddr; 237 int dma_range_checked; 238 239 dma_range_checked = isa_dmarangecheck(addr, nbytes, chan); 240 241 #ifdef DIAGNOSTIC 242 if (chan & ~VALID_DMA_MASK) 243 panic("isa_dmastart: channel out of range"); 244 245 if ((chan < 4 && nbytes > (1<<16)) 246 || (chan >= 4 && (nbytes > (1<<17) || (uintptr_t)addr & 1))) 247 panic("isa_dmastart: impossible request"); 248 249 mtx_lock(&isa_dma_lock); 250 if ((dma_inuse & (1 << chan)) == 0) 251 printf("isa_dmastart: channel %d not acquired\n", chan); 252 #else 253 mtx_lock(&isa_dma_lock); 254 #endif 255 256 #if 0 257 /* 258 * XXX This should be checked, but drivers like ad1848 only call 259 * isa_dmastart() once because they use Auto DMA mode. If we 260 * leave this in, drivers that do this will print this continuously. 261 */ 262 if (dma_busy & (1 << chan)) 263 printf("isa_dmastart: channel %d busy\n", chan); 264 #endif 265 266 dma_busy |= (1 << chan); 267 268 if (dma_range_checked) { 269 if (dma_bouncebuf[chan] == NULL 270 || dma_bouncebufsize[chan] < nbytes) 271 panic("isa_dmastart: bad bounce buffer"); 272 dma_bounced |= (1 << chan); 273 newaddr = dma_bouncebuf[chan]; 274 275 /* copy bounce buffer on write */ 276 if (!(flags & ISADMA_READ)) 277 bcopy(addr, newaddr, nbytes); 278 addr = newaddr; 279 } 280 281 /* translate to physical */ 282 phys = pmap_extract(kernel_pmap, (vm_offset_t)addr); 283 284 if (flags & ISADMA_RAW) { 285 dma_auto_mode |= (1 << chan); 286 } else { 287 dma_auto_mode &= ~(1 << chan); 288 } 289 290 if ((chan & 4) == 0) { 291 /* 292 * Program one of DMA channels 0..3. These are 293 * byte mode channels. 294 */ 295 /* set dma channel mode, and reset address ff */ 296 297 /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 298 if (flags & ISADMA_RAW) { 299 if (flags & ISADMA_READ) 300 outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan); 301 else 302 outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan); 303 } 304 else 305 if (flags & ISADMA_READ) 306 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan); 307 else 308 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan); 309 outb(DMA1_FFC, 0); 310 311 /* send start address */ 312 waport = DMA1_CHN(chan); 313 outb(waport, phys); 314 outb(waport, phys>>8); 315 outb(dmapageport[chan], phys>>16); 316 317 /* send count */ 318 outb(waport + 1, --nbytes); 319 outb(waport + 1, nbytes>>8); 320 321 /* unmask channel */ 322 outb(DMA1_SMSK, chan); 323 } else { 324 /* 325 * Program one of DMA channels 4..7. These are 326 * word mode channels. 327 */ 328 /* set dma channel mode, and reset address ff */ 329 330 /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 331 if (flags & ISADMA_RAW) { 332 if (flags & ISADMA_READ) 333 outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3)); 334 else 335 outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3)); 336 } 337 else 338 if (flags & ISADMA_READ) 339 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3)); 340 else 341 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3)); 342 outb(DMA2_FFC, 0); 343 344 /* send start address */ 345 waport = DMA2_CHN(chan - 4); 346 outb(waport, phys>>1); 347 outb(waport, phys>>9); 348 outb(dmapageport[chan], phys>>16); 349 350 /* send count */ 351 nbytes >>= 1; 352 outb(waport + 2, --nbytes); 353 outb(waport + 2, nbytes>>8); 354 355 /* unmask channel */ 356 outb(DMA2_SMSK, chan & 3); 357 } 358 mtx_unlock(&isa_dma_lock); 359 } 360 361 void 362 isa_dmadone(int flags, caddr_t addr, int nbytes, int chan) 363 { 364 #ifdef DIAGNOSTIC 365 if (chan & ~VALID_DMA_MASK) 366 panic("isa_dmadone: channel out of range"); 367 368 if ((dma_inuse & (1 << chan)) == 0) 369 printf("isa_dmadone: channel %d not acquired\n", chan); 370 #endif 371 372 mtx_lock(&isa_dma_lock); 373 if (((dma_busy & (1 << chan)) == 0) && 374 (dma_auto_mode & (1 << chan)) == 0 ) 375 printf("isa_dmadone: channel %d not busy\n", chan); 376 377 if ((dma_auto_mode & (1 << chan)) == 0) 378 outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4); 379 380 if (dma_bounced & (1 << chan)) { 381 /* copy bounce buffer on read */ 382 if (flags & ISADMA_READ) 383 bcopy(dma_bouncebuf[chan], addr, nbytes); 384 385 dma_bounced &= ~(1 << chan); 386 } 387 dma_busy &= ~(1 << chan); 388 mtx_unlock(&isa_dma_lock); 389 } 390 391 /* 392 * Check for problems with the address range of a DMA transfer 393 * (non-contiguous physical pages, outside of bus address space, 394 * crossing DMA page boundaries). 395 * Return true if special handling needed. 396 */ 397 398 static int 399 isa_dmarangecheck(caddr_t va, u_int length, int chan) 400 { 401 vm_paddr_t phys, priorpage = 0; 402 vm_offset_t endva; 403 u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1); 404 405 endva = (vm_offset_t)round_page((vm_offset_t)va + length); 406 for (; va < (caddr_t) endva ; va += PAGE_SIZE) { 407 phys = trunc_page(pmap_extract(kernel_pmap, (vm_offset_t)va)); 408 if (phys == 0) 409 panic("isa_dmacheck: no physical page present"); 410 if (phys >= ISARAM_END) 411 return (1); 412 if (priorpage) { 413 if (priorpage + PAGE_SIZE != phys) 414 return (1); 415 /* check if crossing a DMA page boundary */ 416 if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk) 417 return (1); 418 } 419 priorpage = phys; 420 } 421 return (0); 422 } 423 424 /* 425 * Query the progress of a transfer on a DMA channel. 426 * 427 * To avoid having to interrupt a transfer in progress, we sample 428 * each of the high and low databytes twice, and apply the following 429 * logic to determine the correct count. 430 * 431 * Reads are performed with interrupts disabled, thus it is to be 432 * expected that the time between reads is very small. At most 433 * one rollover in the low count byte can be expected within the 434 * four reads that are performed. 435 * 436 * There are three gaps in which a rollover can occur : 437 * 438 * - read low1 439 * gap1 440 * - read high1 441 * gap2 442 * - read low2 443 * gap3 444 * - read high2 445 * 446 * If a rollover occurs in gap1 or gap2, the low2 value will be 447 * greater than the low1 value. In this case, low2 and high2 are a 448 * corresponding pair. 449 * 450 * In any other case, low1 and high1 can be considered to be correct. 451 * 452 * The function returns the number of bytes remaining in the transfer, 453 * or -1 if the channel requested is not active. 454 * 455 */ 456 static int 457 isa_dmastatus_locked(int chan) 458 { 459 u_long cnt = 0; 460 int ffport, waport; 461 u_long low1, high1, low2, high2; 462 463 mtx_assert(&isa_dma_lock, MA_OWNED); 464 465 /* channel active? */ 466 if ((dma_inuse & (1 << chan)) == 0) { 467 printf("isa_dmastatus: channel %d not active\n", chan); 468 return(-1); 469 } 470 /* channel busy? */ 471 472 if (((dma_busy & (1 << chan)) == 0) && 473 (dma_auto_mode & (1 << chan)) == 0 ) { 474 printf("chan %d not busy\n", chan); 475 return -2 ; 476 } 477 if (chan < 4) { /* low DMA controller */ 478 ffport = DMA1_FFC; 479 waport = DMA1_CHN(chan) + 1; 480 } else { /* high DMA controller */ 481 ffport = DMA2_FFC; 482 waport = DMA2_CHN(chan - 4) + 2; 483 } 484 485 disable_intr(); /* no interrupts Mr Jones! */ 486 outb(ffport, 0); /* clear register LSB flipflop */ 487 low1 = inb(waport); 488 high1 = inb(waport); 489 outb(ffport, 0); /* clear again */ 490 low2 = inb(waport); 491 high2 = inb(waport); 492 enable_intr(); /* enable interrupts again */ 493 494 /* 495 * Now decide if a wrap has tried to skew our results. 496 * Note that after TC, the count will read 0xffff, while we want 497 * to return zero, so we add and then mask to compensate. 498 */ 499 if (low1 >= low2) { 500 cnt = (low1 + (high1 << 8) + 1) & 0xffff; 501 } else { 502 cnt = (low2 + (high2 << 8) + 1) & 0xffff; 503 } 504 505 if (chan >= 4) /* high channels move words */ 506 cnt *= 2; 507 return(cnt); 508 } 509 510 int 511 isa_dmastatus(int chan) 512 { 513 int status; 514 515 mtx_lock(&isa_dma_lock); 516 status = isa_dmastatus_locked(chan); 517 mtx_unlock(&isa_dma_lock); 518 519 return (status); 520 } 521 522 /* 523 * Reached terminal count yet ? 524 */ 525 int 526 isa_dmatc(int chan) 527 { 528 529 if (chan < 4) 530 return(inb(DMA1_STATUS) & (1 << chan)); 531 else 532 return(inb(DMA2_STATUS) & (1 << (chan & 3))); 533 } 534 535 /* 536 * Stop a DMA transfer currently in progress. 537 */ 538 int 539 isa_dmastop(int chan) 540 { 541 int status; 542 543 mtx_lock(&isa_dma_lock); 544 if ((dma_inuse & (1 << chan)) == 0) 545 printf("isa_dmastop: channel %d not acquired\n", chan); 546 547 if (((dma_busy & (1 << chan)) == 0) && 548 ((dma_auto_mode & (1 << chan)) == 0)) { 549 printf("chan %d not busy\n", chan); 550 mtx_unlock(&isa_dma_lock); 551 return -2 ; 552 } 553 554 if ((chan & 4) == 0) { 555 outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */); 556 } else { 557 outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */); 558 } 559 560 status = isa_dmastatus_locked(chan); 561 562 mtx_unlock(&isa_dma_lock); 563 564 return (status); 565 } 566 567 /* 568 * Attach to the ISA PnP descriptor for the AT DMA controller 569 */ 570 static struct isa_pnp_id atdma_ids[] = { 571 { 0x0002d041 /* PNP0200 */, "AT DMA controller" }, 572 { 0 } 573 }; 574 575 static int 576 atdma_probe(device_t dev) 577 { 578 int result; 579 580 if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0) 581 device_quiet(dev); 582 return(result); 583 } 584 585 static int 586 atdma_attach(device_t dev) 587 { 588 return(0); 589 } 590 591 static device_method_t atdma_methods[] = { 592 /* Device interface */ 593 DEVMETHOD(device_probe, atdma_probe), 594 DEVMETHOD(device_attach, atdma_attach), 595 DEVMETHOD(device_detach, bus_generic_detach), 596 DEVMETHOD(device_shutdown, bus_generic_shutdown), 597 DEVMETHOD(device_suspend, bus_generic_suspend), 598 DEVMETHOD(device_resume, bus_generic_resume), 599 { 0, 0 } 600 }; 601 602 static driver_t atdma_driver = { 603 "atdma", 604 atdma_methods, 605 1, /* no softc */ 606 }; 607 608 static devclass_t atdma_devclass; 609 610 DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0); 611 DRIVER_MODULE(atdma, acpi, atdma_driver, atdma_devclass, 0, 0); 612 ISA_PNP_INFO(atdma_ids); 613