hw/ide/pci.c

   1 /*
   2  * QEMU IDE Emulation: PCI Bus support.
   3  *
   4  * Copyright (c) 2003 Fabrice Bellard
   5  * Copyright (c) 2006 Openedhand Ltd.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25 #include <hw/hw.h>
  26 #include <hw/i386/pc.h>
  27 #include <hw/pci/pci.h>
  28 #include <hw/isa/isa.h>
  29 #include "sysemu/block-backend.h"
  30 #include "sysemu/dma.h"
  31 #include "qemu/error-report.h"
  32 #include <hw/ide/pci.h>
  33
  34 #define BMDMA_PAGE_SIZE 4096
  35
  36 #define BM_MIGRATION_COMPAT_STATUS_BITS \
  37         (IDE_RETRY_DMA | IDE_RETRY_PIO | \
  38         IDE_RETRY_READ | IDE_RETRY_FLUSH)
  39
  40 static void bmdma_start_dma(IDEDMA *dma, IDEState *s,
  41                             BlockCompletionFunc *dma_cb)
  42 {
  43     BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma);
  44
  45     bm->dma_cb = dma_cb;
  46     bm->cur_prd_last = 0;
  47     bm->cur_prd_addr = 0;
  48     bm->cur_prd_len = 0;
  49
  50     if (bm->status & BM_STATUS_DMAING) {
  51         bm->dma_cb(bmdma_active_if(bm), 0);
  52     }
  53 }
  54
  55 /**
  56  * Prepare an sglist based on available PRDs.
  57  * @limit: How many bytes to prepare total.
  58  *
  59  * Returns the number of bytes prepared, -1 on error.
  60  * IDEState.io_buffer_size will contain the number of bytes described
  61  * by the PRDs, whether or not we added them to the sglist.
  62  */
  63 static int32_t bmdma_prepare_buf(IDEDMA *dma, int32_t limit)
  64 {
  65     BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma);
  66     IDEState *s = bmdma_active_if(bm);
  67     PCIDevice *pci_dev = PCI_DEVICE(bm->pci_dev);
  68     struct {
  69         uint32_t addr;
  70         uint32_t size;
  71     } prd;
  72     int l, len;
  73
  74     pci_dma_sglist_init(&s->sg, pci_dev,
  75                         s->nsector / (BMDMA_PAGE_SIZE / 512) + 1);
  76     s->io_buffer_size = 0;
  77     for(;;) {
  78         if (bm->cur_prd_len == 0) {
  79             /* end of table (with a fail safe of one page) */
  80             if (bm->cur_prd_last ||
  81                 (bm->cur_addr - bm->addr) >= BMDMA_PAGE_SIZE) {
  82                 return s->sg.size;
  83             }
  84             pci_dma_read(pci_dev, bm->cur_addr, &prd, 8);
  85             bm->cur_addr += 8;
  86             prd.addr = le32_to_cpu(prd.addr);
  87             prd.size = le32_to_cpu(prd.size);
  88             len = prd.size & 0xfffe;
  89             if (len == 0)
  90                 len = 0x10000;
  91             bm->cur_prd_len = len;
  92             bm->cur_prd_addr = prd.addr;
  93             bm->cur_prd_last = (prd.size & 0x80000000);
  94         }
  95         l = bm->cur_prd_len;
  96         if (l > 0) {
  97             uint64_t sg_len;
  98
  99             /* Don't add extra bytes to the SGList; consume any remaining
 100              * PRDs from the guest, but ignore them. */
 101             sg_len = MIN(limit - s->sg.size, bm->cur_prd_len);
 102             if (sg_len) {
 103                 qemu_sglist_add(&s->sg, bm->cur_prd_addr, sg_len);
 104             }
 105
 106             bm->cur_prd_addr += l;
 107             bm->cur_prd_len -= l;
 108             s->io_buffer_size += l;
 109         }
 110     }
 111
 112     qemu_sglist_destroy(&s->sg);
 113     s->io_buffer_size = 0;
 114     return -1;
 115 }
 116
 117 /* return 0 if buffer completed */
 118 static int bmdma_rw_buf(IDEDMA *dma, int is_write)
 119 {
 120     BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma);
 121     IDEState *s = bmdma_active_if(bm);
 122     PCIDevice *pci_dev = PCI_DEVICE(bm->pci_dev);
 123     struct {
 124         uint32_t addr;
 125         uint32_t size;
 126     } prd;
 127     int l, len;
 128
 129     for(;;) {
 130         l = s->io_buffer_size - s->io_buffer_index;
 131         if (l <= 0)
 132             break;
 133         if (bm->cur_prd_len == 0) {
 134             /* end of table (with a fail safe of one page) */
 135             if (bm->cur_prd_last ||
 136                 (bm->cur_addr - bm->addr) >= BMDMA_PAGE_SIZE)
 137                 return 0;
 138             pci_dma_read(pci_dev, bm->cur_addr, &prd, 8);
 139             bm->cur_addr += 8;
 140             prd.addr = le32_to_cpu(prd.addr);
 141             prd.size = le32_to_cpu(prd.size);
 142             len = prd.size & 0xfffe;
 143             if (len == 0)
 144                 len = 0x10000;
 145             bm->cur_prd_len = len;
 146             bm->cur_prd_addr = prd.addr;
 147             bm->cur_prd_last = (prd.size & 0x80000000);
 148         }
 149         if (l > bm->cur_prd_len)
 150             l = bm->cur_prd_len;
 151         if (l > 0) {
 152             if (is_write) {
 153                 pci_dma_write(pci_dev, bm->cur_prd_addr,
 154                               s->io_buffer + s->io_buffer_index, l);
 155             } else {
 156                 pci_dma_read(pci_dev, bm->cur_prd_addr,
 157                              s->io_buffer + s->io_buffer_index, l);
 158             }
 159             bm->cur_prd_addr += l;
 160             bm->cur_prd_len -= l;
 161             s->io_buffer_index += l;
 162         }
 163     }
 164     return 1;
 165 }
 166
 167 static void bmdma_set_inactive(IDEDMA *dma, bool more)
 168 {
 169     BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma);
 170
 171     bm->dma_cb = NULL;
 172     if (more) {
 173         bm->status |= BM_STATUS_DMAING;
 174     } else {
 175         bm->status &= ~BM_STATUS_DMAING;
 176     }
 177 }
 178
 179 static void bmdma_restart_dma(IDEDMA *dma)
 180 {
 181     BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma);
 182
 183     bm->cur_addr = bm->addr;
 184 }
 185
 186 static void bmdma_cancel(BMDMAState *bm)
 187 {
 188     if (bm->status & BM_STATUS_DMAING) {
 189         /* cancel DMA request */
 190         bmdma_set_inactive(&bm->dma, false);
 191     }
 192 }
 193
 194 static void bmdma_reset(IDEDMA *dma)
 195 {
 196     BMDMAState *bm = DO_UPCAST(BMDMAState, dma, dma);
 197
 198 #ifdef DEBUG_IDE
 199     printf("ide: dma_reset\n");
 200 #endif
 201     bmdma_cancel(bm);
 202     bm->cmd = 0;
 203     bm->status = 0;
 204     bm->addr = 0;
 205     bm->cur_addr = 0;
 206     bm->cur_prd_last = 0;
 207     bm->cur_prd_addr = 0;
 208     bm->cur_prd_len = 0;
 209 }
 210
 211 static void bmdma_irq(void *opaque, int n, int level)
 212 {
 213     BMDMAState *bm = opaque;
 214
 215     if (!level) {
 216         /* pass through lower */
 217         qemu_set_irq(bm->irq, level);
 218         return;
 219     }
 220
 221     bm->status |= BM_STATUS_INT;
 222
 223     /* trigger the real irq */
 224     qemu_set_irq(bm->irq, level);
 225 }
 226
 227 void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val)
 228 {
 229 #ifdef DEBUG_IDE
 230     printf("%s: 0x%08x\n", __func__, val);
 231 #endif
 232
 233     /* Ignore writes to SSBM if it keeps the old value */
 234     if ((val & BM_CMD_START) != (bm->cmd & BM_CMD_START)) {
 235         if (!(val & BM_CMD_START)) {
 236             /* First invoke the callbacks of all buffered requests
 237              * and flag those requests as orphaned. Ideally there
 238              * are no unbuffered (Scatter Gather DMA Requests or
 239              * write requests) pending and we can avoid to drain. */
 240             IDEBufferedRequest *req;
 241             IDEState *s = idebus_active_if(bm->bus);
 242             QLIST_FOREACH(req, &s->buffered_requests, list) {
 243                 if (!req->orphaned) {
 244 #ifdef DEBUG_IDE
 245                     printf("%s: invoking cb %p of buffered request %p with"
 246                            " -ECANCELED\n", __func__, req->original_cb, req);
 247 #endif
 248                     req->original_cb(req->original_opaque, -ECANCELED);
 249                 }
 250                 req->orphaned = true;
 251             }
 252             /*
 253              * We can't cancel Scatter Gather DMA in the middle of the
 254              * operation or a partial (not full) DMA transfer would reach
 255              * the storage so we wait for completion instead (we beahve
 256              * like if the DMA was completed by the time the guest trying
 257              * to cancel dma with bmdma_cmd_writeb with BM_CMD_START not
 258              * set).
 259              *
 260              * In the future we'll be able to safely cancel the I/O if the
 261              * whole DMA operation will be submitted to disk with a single
 262              * aio operation with preadv/pwritev.
 263              */
 264             if (bm->bus->dma->aiocb) {
 265 #ifdef DEBUG_IDE
 266                 printf("%s: draining all remaining requests", __func__);
 267 #endif
 268                 blk_drain_all();
 269                 assert(bm->bus->dma->aiocb == NULL);
 270             }
 271             bm->status &= ~BM_STATUS_DMAING;
 272         } else {
 273             bm->cur_addr = bm->addr;
 274             if (!(bm->status & BM_STATUS_DMAING)) {
 275                 bm->status |= BM_STATUS_DMAING;
 276                 /* start dma transfer if possible */
 277                 if (bm->dma_cb)
 278                     bm->dma_cb(bmdma_active_if(bm), 0);
 279             }
 280         }
 281     }
 282
 283     bm->cmd = val & 0x09;
 284 }
 285
 286 static uint64_t bmdma_addr_read(void *opaque, hwaddr addr,
 287                                 unsigned width)
 288 {
 289     BMDMAState *bm = opaque;
 290     uint32_t mask = (1ULL << (width * 8)) - 1;
 291     uint64_t data;
 292
 293     data = (bm->addr >> (addr * 8)) & mask;
 294 #ifdef DEBUG_IDE
 295     printf("%s: 0x%08x\n", __func__, (unsigned)data);
 296 #endif
 297     return data;
 298 }
 299
 300 static void bmdma_addr_write(void *opaque, hwaddr addr,
 301                              uint64_t data, unsigned width)
 302 {
 303     BMDMAState *bm = opaque;
 304     int shift = addr * 8;
 305     uint32_t mask = (1ULL << (width * 8)) - 1;
 306
 307 #ifdef DEBUG_IDE
 308     printf("%s: 0x%08x\n", __func__, (unsigned)data);
 309 #endif
 310     bm->addr &= ~(mask << shift);
 311     bm->addr |= ((data & mask) << shift) & ~3;
 312 }
 313
 314 MemoryRegionOps bmdma_addr_ioport_ops = {
 315     .read = bmdma_addr_read,
 316     .write = bmdma_addr_write,
 317     .endianness = DEVICE_LITTLE_ENDIAN,
 318 };
 319
 320 static bool ide_bmdma_current_needed(void *opaque)
 321 {
 322     BMDMAState *bm = opaque;
 323
 324     return (bm->cur_prd_len != 0);
 325 }
 326
 327 static bool ide_bmdma_status_needed(void *opaque)
 328 {
 329     BMDMAState *bm = opaque;
 330
 331     /* Older versions abused some bits in the status register for internal
 332      * error state. If any of these bits are set, we must add a subsection to
 333      * transfer the real status register */
 334     uint8_t abused_bits = BM_MIGRATION_COMPAT_STATUS_BITS;
 335
 336     return ((bm->status & abused_bits) != 0);
 337 }
 338
 339 static void ide_bmdma_pre_save(void *opaque)
 340 {
 341     BMDMAState *bm = opaque;
 342     uint8_t abused_bits = BM_MIGRATION_COMPAT_STATUS_BITS;
 343
 344     bm->migration_retry_unit = bm->bus->retry_unit;
 345     bm->migration_retry_sector_num = bm->bus->retry_sector_num;
 346     bm->migration_retry_nsector = bm->bus->retry_nsector;
 347     bm->migration_compat_status =
 348         (bm->status & ~abused_bits) | (bm->bus->error_status & abused_bits);
 349 }
 350
 351 /* This function accesses bm->bus->error_status which is loaded only after
 352  * BMDMA itself. This is why the function is called from ide_pci_post_load
 353  * instead of being registered with VMState where it would run too early. */
 354 static int ide_bmdma_post_load(void *opaque, int version_id)
 355 {
 356     BMDMAState *bm = opaque;
 357     uint8_t abused_bits = BM_MIGRATION_COMPAT_STATUS_BITS;
 358
 359     if (bm->status == 0) {
 360         bm->status = bm->migration_compat_status & ~abused_bits;
 361         bm->bus->error_status |= bm->migration_compat_status & abused_bits;
 362     }
 363     if (bm->bus->error_status) {
 364         bm->bus->retry_sector_num = bm->migration_retry_sector_num;
 365         bm->bus->retry_nsector = bm->migration_retry_nsector;
 366         bm->bus->retry_unit = bm->migration_retry_unit;
 367     }
 368
 369     return 0;
 370 }
 371
 372 static const VMStateDescription vmstate_bmdma_current = {
 373     .name = "ide bmdma_current",
 374     .version_id = 1,
 375     .minimum_version_id = 1,
 376     .needed = ide_bmdma_current_needed,
 377     .fields = (VMStateField[]) {
 378         VMSTATE_UINT32(cur_addr, BMDMAState),
 379         VMSTATE_UINT32(cur_prd_last, BMDMAState),
 380         VMSTATE_UINT32(cur_prd_addr, BMDMAState),
 381         VMSTATE_UINT32(cur_prd_len, BMDMAState),
 382         VMSTATE_END_OF_LIST()
 383     }
 384 };
 385
 386 static const VMStateDescription vmstate_bmdma_status = {
 387     .name ="ide bmdma/status",
 388     .version_id = 1,
 389     .minimum_version_id = 1,
 390     .needed = ide_bmdma_status_needed,
 391     .fields = (VMStateField[]) {
 392         VMSTATE_UINT8(status, BMDMAState),
 393         VMSTATE_END_OF_LIST()
 394     }
 395 };
 396
 397 static const VMStateDescription vmstate_bmdma = {
 398     .name = "ide bmdma",
 399     .version_id = 3,
 400     .minimum_version_id = 0,
 401     .pre_save  = ide_bmdma_pre_save,
 402     .fields = (VMStateField[]) {
 403         VMSTATE_UINT8(cmd, BMDMAState),
 404         VMSTATE_UINT8(migration_compat_status, BMDMAState),
 405         VMSTATE_UINT32(addr, BMDMAState),
 406         VMSTATE_INT64(migration_retry_sector_num, BMDMAState),
 407         VMSTATE_UINT32(migration_retry_nsector, BMDMAState),
 408         VMSTATE_UINT8(migration_retry_unit, BMDMAState),
 409         VMSTATE_END_OF_LIST()
 410     },
 411     .subsections = (const VMStateDescription*[]) {
 412         &vmstate_bmdma_current,
 413         &vmstate_bmdma_status,
 414         NULL
 415     }
 416 };
 417
 418 static int ide_pci_post_load(void *opaque, int version_id)
 419 {
 420     PCIIDEState *d = opaque;
 421     int i;
 422
 423     for(i = 0; i < 2; i++) {
 424         /* current versions always store 0/1, but older version
 425            stored bigger values. We only need last bit */
 426         d->bmdma[i].migration_retry_unit &= 1;
 427         ide_bmdma_post_load(&d->bmdma[i], -1);
 428     }
 429
 430     return 0;
 431 }
 432
 433 const VMStateDescription vmstate_ide_pci = {
 434     .name = "ide",
 435     .version_id = 3,
 436     .minimum_version_id = 0,
 437     .post_load = ide_pci_post_load,
 438     .fields = (VMStateField[]) {
 439         VMSTATE_PCI_DEVICE(parent_obj, PCIIDEState),
 440         VMSTATE_STRUCT_ARRAY(bmdma, PCIIDEState, 2, 0,
 441                              vmstate_bmdma, BMDMAState),
 442         VMSTATE_IDE_BUS_ARRAY(bus, PCIIDEState, 2),
 443         VMSTATE_IDE_DRIVES(bus[0].ifs, PCIIDEState),
 444         VMSTATE_IDE_DRIVES(bus[1].ifs, PCIIDEState),
 445         VMSTATE_END_OF_LIST()
 446     }
 447 };
 448
 449 void pci_ide_create_devs(PCIDevice *dev, DriveInfo **hd_table)
 450 {
 451     PCIIDEState *d = PCI_IDE(dev);
 452     static const int bus[4]  = { 0, 0, 1, 1 };
 453     static const int unit[4] = { 0, 1, 0, 1 };
 454     int i;
 455
 456     for (i = 0; i < 4; i++) {
 457         if (hd_table[i] == NULL)
 458             continue;
 459         ide_create_drive(d->bus+bus[i], unit[i], hd_table[i]);
 460     }
 461 }
 462
 463 static const struct IDEDMAOps bmdma_ops = {
 464     .start_dma = bmdma_start_dma,
 465     .prepare_buf = bmdma_prepare_buf,
 466     .rw_buf = bmdma_rw_buf,
 467     .restart_dma = bmdma_restart_dma,
 468     .set_inactive = bmdma_set_inactive,
 469     .reset = bmdma_reset,
 470 };
 471
 472 void bmdma_init(IDEBus *bus, BMDMAState *bm, PCIIDEState *d)
 473 {
 474     if (bus->dma == &bm->dma) {
 475         return;
 476     }
 477
 478     bm->dma.ops = &bmdma_ops;
 479     bus->dma = &bm->dma;
 480     bm->irq = bus->irq;
 481     bus->irq = qemu_allocate_irq(bmdma_irq, bm, 0);
 482     bm->pci_dev = d;
 483 }
 484
 485 static const TypeInfo pci_ide_type_info = {
 486     .name = TYPE_PCI_IDE,
 487     .parent = TYPE_PCI_DEVICE,
 488     .instance_size = sizeof(PCIIDEState),
 489     .abstract = true,
 490 };
 491
 492 static void pci_ide_register_types(void)
 493 {
 494     type_register_static(&pci_ide_type_info);
 495 }
 496
 497 type_init(pci_ide_register_types)