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 /* Try malloc() first. It works better if it works. */ 99 buf = malloc(bouncebufsize, M_DEVBUF, flag); 100 if (buf != NULL) { 101 if (isa_dmarangecheck(buf, bouncebufsize, chan) != 0) { 102 free(buf, M_DEVBUF); 103 buf = NULL; 104 } 105 contig = 0; 106 } 107 108 if (buf == NULL) { 109 buf = contigmalloc(bouncebufsize, M_DEVBUF, flag, 0ul, 0xfffffful, 110 1ul, chan & 4 ? 0x20000ul : 0x10000ul); 111 contig = 1; 112 } 113 114 if (buf == NULL) 115 return (ENOMEM); 116 117 mtx_lock(&isa_dma_lock); 118 /* 119 * If a DMA channel is shared, both drivers have to call isa_dma_init 120 * since they don't know that the other driver will do it. 121 * Just return if we're already set up good. 122 * XXX: this only works if they agree on the bouncebuf size. This 123 * XXX: is typically the case since they are multiple instances of 124 * XXX: the same driver. 125 */ 126 if (dma_bouncebuf[chan] != NULL) { 127 if (contig) 128 contigfree(buf, bouncebufsize, M_DEVBUF); 129 else 130 free(buf, M_DEVBUF); 131 mtx_unlock(&isa_dma_lock); 132 return (0); 133 } 134 135 dma_bouncebufsize[chan] = bouncebufsize; 136 dma_bouncebuf[chan] = buf; 137 138 mtx_unlock(&isa_dma_lock); 139 140 return (0); 141 } 142 143 /* 144 * Register a DMA channel's usage. Usually called from a device driver 145 * in open() or during its initialization. 146 */ 147 int 148 isa_dma_acquire(int chan) 149 { 150 #ifdef DIAGNOSTIC 151 if (chan & ~VALID_DMA_MASK) 152 panic("isa_dma_acquire: channel out of range"); 153 #endif 154 155 mtx_lock(&isa_dma_lock); 156 if (dma_inuse & (1 << chan)) { 157 printf("isa_dma_acquire: channel %d already in use\n", chan); 158 mtx_unlock(&isa_dma_lock); 159 return (EBUSY); 160 } 161 dma_inuse |= (1 << chan); 162 dma_auto_mode &= ~(1 << chan); 163 mtx_unlock(&isa_dma_lock); 164 165 return (0); 166 } 167 168 /* 169 * Unregister a DMA channel's usage. Usually called from a device driver 170 * during close() or during its shutdown. 171 */ 172 void 173 isa_dma_release(int chan) 174 { 175 #ifdef DIAGNOSTIC 176 if (chan & ~VALID_DMA_MASK) 177 panic("isa_dma_release: channel out of range"); 178 179 mtx_lock(&isa_dma_lock); 180 if ((dma_inuse & (1 << chan)) == 0) 181 printf("isa_dma_release: channel %d not in use\n", chan); 182 #else 183 mtx_lock(&isa_dma_lock); 184 #endif 185 186 if (dma_busy & (1 << chan)) { 187 dma_busy &= ~(1 << chan); 188 /* 189 * XXX We should also do "dma_bounced &= (1 << chan);" 190 * because we are acting on behalf of isa_dmadone() which 191 * was not called to end the last DMA operation. This does 192 * not matter now, but it may in the future. 193 */ 194 } 195 196 dma_inuse &= ~(1 << chan); 197 dma_auto_mode &= ~(1 << chan); 198 199 mtx_unlock(&isa_dma_lock); 200 } 201 202 /* 203 * isa_dmacascade(): program 8237 DMA controller channel to accept 204 * external dma control by a board. 205 */ 206 void 207 isa_dmacascade(int chan) 208 { 209 #ifdef DIAGNOSTIC 210 if (chan & ~VALID_DMA_MASK) 211 panic("isa_dmacascade: channel out of range"); 212 #endif 213 214 mtx_lock(&isa_dma_lock); 215 /* set dma channel mode, and set dma channel mode */ 216 if ((chan & 4) == 0) { 217 outb(DMA1_MODE, DMA37MD_CASCADE | chan); 218 outb(DMA1_SMSK, chan); 219 } else { 220 outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3)); 221 outb(DMA2_SMSK, chan & 3); 222 } 223 mtx_unlock(&isa_dma_lock); 224 } 225 226 /* 227 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment 228 * problems by using a bounce buffer. 229 */ 230 void 231 isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan) 232 { 233 vm_paddr_t phys; 234 int waport; 235 caddr_t newaddr; 236 int dma_range_checked; 237 238 dma_range_checked = isa_dmarangecheck(addr, nbytes, chan); 239 240 #ifdef DIAGNOSTIC 241 if (chan & ~VALID_DMA_MASK) 242 panic("isa_dmastart: channel out of range"); 243 244 if ((chan < 4 && nbytes > (1<<16)) 245 || (chan >= 4 && (nbytes > (1<<17) || (uintptr_t)addr & 1))) 246 panic("isa_dmastart: impossible request"); 247 248 mtx_lock(&isa_dma_lock); 249 if ((dma_inuse & (1 << chan)) == 0) 250 printf("isa_dmastart: channel %d not acquired\n", chan); 251 #else 252 mtx_lock(&isa_dma_lock); 253 #endif 254 255 #if 0 256 /* 257 * XXX This should be checked, but drivers like ad1848 only call 258 * isa_dmastart() once because they use Auto DMA mode. If we 259 * leave this in, drivers that do this will print this continuously. 260 */ 261 if (dma_busy & (1 << chan)) 262 printf("isa_dmastart: channel %d busy\n", chan); 263 #endif 264 265 dma_busy |= (1 << chan); 266 267 if (dma_range_checked) { 268 if (dma_bouncebuf[chan] == NULL 269 || dma_bouncebufsize[chan] < nbytes) 270 panic("isa_dmastart: bad bounce buffer"); 271 dma_bounced |= (1 << chan); 272 newaddr = dma_bouncebuf[chan]; 273 274 /* copy bounce buffer on write */ 275 if (!(flags & ISADMA_READ)) 276 bcopy(addr, newaddr, nbytes); 277 addr = newaddr; 278 } 279 280 /* translate to physical */ 281 phys = pmap_extract(kernel_pmap, (vm_offset_t)addr); 282 283 if (flags & ISADMA_RAW) { 284 dma_auto_mode |= (1 << chan); 285 } else { 286 dma_auto_mode &= ~(1 << chan); 287 } 288 289 if ((chan & 4) == 0) { 290 /* 291 * Program one of DMA channels 0..3. These are 292 * byte mode channels. 293 */ 294 /* set dma channel mode, and reset address ff */ 295 296 /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 297 if (flags & ISADMA_RAW) { 298 if (flags & ISADMA_READ) 299 outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan); 300 else 301 outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan); 302 } 303 else 304 if (flags & ISADMA_READ) 305 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan); 306 else 307 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan); 308 outb(DMA1_FFC, 0); 309 310 /* send start address */ 311 waport = DMA1_CHN(chan); 312 outb(waport, phys); 313 outb(waport, phys>>8); 314 outb(dmapageport[chan], phys>>16); 315 316 /* send count */ 317 outb(waport + 1, --nbytes); 318 outb(waport + 1, nbytes>>8); 319 320 /* unmask channel */ 321 outb(DMA1_SMSK, chan); 322 } else { 323 /* 324 * Program one of DMA channels 4..7. These are 325 * word mode channels. 326 */ 327 /* set dma channel mode, and reset address ff */ 328 329 /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 330 if (flags & ISADMA_RAW) { 331 if (flags & ISADMA_READ) 332 outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3)); 333 else 334 outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3)); 335 } 336 else 337 if (flags & ISADMA_READ) 338 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3)); 339 else 340 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3)); 341 outb(DMA2_FFC, 0); 342 343 /* send start address */ 344 waport = DMA2_CHN(chan - 4); 345 outb(waport, phys>>1); 346 outb(waport, phys>>9); 347 outb(dmapageport[chan], phys>>16); 348 349 /* send count */ 350 nbytes >>= 1; 351 outb(waport + 2, --nbytes); 352 outb(waport + 2, nbytes>>8); 353 354 /* unmask channel */ 355 outb(DMA2_SMSK, chan & 3); 356 } 357 mtx_unlock(&isa_dma_lock); 358 } 359 360 void 361 isa_dmadone(int flags, caddr_t addr, int nbytes, int chan) 362 { 363 #ifdef DIAGNOSTIC 364 if (chan & ~VALID_DMA_MASK) 365 panic("isa_dmadone: channel out of range"); 366 367 if ((dma_inuse & (1 << chan)) == 0) 368 printf("isa_dmadone: channel %d not acquired\n", chan); 369 #endif 370 371 mtx_lock(&isa_dma_lock); 372 if (((dma_busy & (1 << chan)) == 0) && 373 (dma_auto_mode & (1 << chan)) == 0 ) 374 printf("isa_dmadone: channel %d not busy\n", chan); 375 376 if ((dma_auto_mode & (1 << chan)) == 0) 377 outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4); 378 379 if (dma_bounced & (1 << chan)) { 380 /* copy bounce buffer on read */ 381 if (flags & ISADMA_READ) 382 bcopy(dma_bouncebuf[chan], addr, nbytes); 383 384 dma_bounced &= ~(1 << chan); 385 } 386 dma_busy &= ~(1 << chan); 387 mtx_unlock(&isa_dma_lock); 388 } 389 390 /* 391 * Check for problems with the address range of a DMA transfer 392 * (non-contiguous physical pages, outside of bus address space, 393 * crossing DMA page boundaries). 394 * Return true if special handling needed. 395 */ 396 397 static int 398 isa_dmarangecheck(caddr_t va, u_int length, int chan) 399 { 400 vm_paddr_t phys, priorpage = 0; 401 vm_offset_t endva; 402 u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1); 403 404 endva = (vm_offset_t)round_page((vm_offset_t)va + length); 405 for (; va < (caddr_t) endva ; va += PAGE_SIZE) { 406 phys = trunc_page(pmap_extract(kernel_pmap, (vm_offset_t)va)); 407 if (phys == 0) 408 panic("isa_dmacheck: no physical page present"); 409 if (phys >= ISARAM_END) 410 return (1); 411 if (priorpage) { 412 if (priorpage + PAGE_SIZE != phys) 413 return (1); 414 /* check if crossing a DMA page boundary */ 415 if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk) 416 return (1); 417 } 418 priorpage = phys; 419 } 420 return (0); 421 } 422 423 /* 424 * Query the progress of a transfer on a DMA channel. 425 * 426 * To avoid having to interrupt a transfer in progress, we sample 427 * each of the high and low databytes twice, and apply the following 428 * logic to determine the correct count. 429 * 430 * Reads are performed with interrupts disabled, thus it is to be 431 * expected that the time between reads is very small. At most 432 * one rollover in the low count byte can be expected within the 433 * four reads that are performed. 434 * 435 * There are three gaps in which a rollover can occur : 436 * 437 * - read low1 438 * gap1 439 * - read high1 440 * gap2 441 * - read low2 442 * gap3 443 * - read high2 444 * 445 * If a rollover occurs in gap1 or gap2, the low2 value will be 446 * greater than the low1 value. In this case, low2 and high2 are a 447 * corresponding pair. 448 * 449 * In any other case, low1 and high1 can be considered to be correct. 450 * 451 * The function returns the number of bytes remaining in the transfer, 452 * or -1 if the channel requested is not active. 453 * 454 */ 455 static int 456 isa_dmastatus_locked(int chan) 457 { 458 u_long cnt = 0; 459 int ffport, waport; 460 u_long low1, high1, low2, high2; 461 462 mtx_assert(&isa_dma_lock, MA_OWNED); 463 464 /* channel active? */ 465 if ((dma_inuse & (1 << chan)) == 0) { 466 printf("isa_dmastatus: channel %d not active\n", chan); 467 return(-1); 468 } 469 /* channel busy? */ 470 471 if (((dma_busy & (1 << chan)) == 0) && 472 (dma_auto_mode & (1 << chan)) == 0 ) { 473 printf("chan %d not busy\n", chan); 474 return -2 ; 475 } 476 if (chan < 4) { /* low DMA controller */ 477 ffport = DMA1_FFC; 478 waport = DMA1_CHN(chan) + 1; 479 } else { /* high DMA controller */ 480 ffport = DMA2_FFC; 481 waport = DMA2_CHN(chan - 4) + 2; 482 } 483 484 disable_intr(); /* no interrupts Mr Jones! */ 485 outb(ffport, 0); /* clear register LSB flipflop */ 486 low1 = inb(waport); 487 high1 = inb(waport); 488 outb(ffport, 0); /* clear again */ 489 low2 = inb(waport); 490 high2 = inb(waport); 491 enable_intr(); /* enable interrupts again */ 492 493 /* 494 * Now decide if a wrap has tried to skew our results. 495 * Note that after TC, the count will read 0xffff, while we want 496 * to return zero, so we add and then mask to compensate. 497 */ 498 if (low1 >= low2) { 499 cnt = (low1 + (high1 << 8) + 1) & 0xffff; 500 } else { 501 cnt = (low2 + (high2 << 8) + 1) & 0xffff; 502 } 503 504 if (chan >= 4) /* high channels move words */ 505 cnt *= 2; 506 return(cnt); 507 } 508 509 int 510 isa_dmastatus(int chan) 511 { 512 int status; 513 514 mtx_lock(&isa_dma_lock); 515 status = isa_dmastatus_locked(chan); 516 mtx_unlock(&isa_dma_lock); 517 518 return (status); 519 } 520 521 /* 522 * Reached terminal count yet ? 523 */ 524 int 525 isa_dmatc(int chan) 526 { 527 528 if (chan < 4) 529 return(inb(DMA1_STATUS) & (1 << chan)); 530 else 531 return(inb(DMA2_STATUS) & (1 << (chan & 3))); 532 } 533 534 /* 535 * Stop a DMA transfer currently in progress. 536 */ 537 int 538 isa_dmastop(int chan) 539 { 540 int status; 541 542 mtx_lock(&isa_dma_lock); 543 if ((dma_inuse & (1 << chan)) == 0) 544 printf("isa_dmastop: channel %d not acquired\n", chan); 545 546 if (((dma_busy & (1 << chan)) == 0) && 547 ((dma_auto_mode & (1 << chan)) == 0)) { 548 printf("chan %d not busy\n", chan); 549 mtx_unlock(&isa_dma_lock); 550 return -2 ; 551 } 552 553 if ((chan & 4) == 0) { 554 outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */); 555 } else { 556 outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */); 557 } 558 559 status = isa_dmastatus_locked(chan); 560 561 mtx_unlock(&isa_dma_lock); 562 563 return (status); 564 } 565 566 /* 567 * Attach to the ISA PnP descriptor for the AT DMA controller 568 */ 569 static struct isa_pnp_id atdma_ids[] = { 570 { 0x0002d041 /* PNP0200 */, "AT DMA controller" }, 571 { 0 } 572 }; 573 574 static int 575 atdma_probe(device_t dev) 576 { 577 int result; 578 579 if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0) 580 device_quiet(dev); 581 return(result); 582 } 583 584 static int 585 atdma_attach(device_t dev) 586 { 587 return(0); 588 } 589 590 static device_method_t atdma_methods[] = { 591 /* Device interface */ 592 DEVMETHOD(device_probe, atdma_probe), 593 DEVMETHOD(device_attach, atdma_attach), 594 DEVMETHOD(device_detach, bus_generic_detach), 595 DEVMETHOD(device_shutdown, bus_generic_shutdown), 596 DEVMETHOD(device_suspend, bus_generic_suspend), 597 DEVMETHOD(device_resume, bus_generic_resume), 598 { 0, 0 } 599 }; 600 601 static driver_t atdma_driver = { 602 "atdma", 603 atdma_methods, 604 1, /* no softc */ 605 }; 606 607 static devclass_t atdma_devclass; 608 609 DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0); 610 DRIVER_MODULE(atdma, acpi, atdma_driver, atdma_devclass, 0, 0); 611 ISA_PNP_INFO(atdma_ids); 612