drivers/scsi/sun_esp.c

   1 /* sun_esp.c: ESP front-end for Sparc SBUS systems.
   2  *
   3  * Copyright (C) 2007, 2008 David S. Miller (davem@davemloft.net)
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/types.h>
   8 #include <linux/delay.h>
   9 #include <linux/module.h>
  10 #include <linux/mm.h>
  11 #include <linux/init.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/of.h>
  14 #include <linux/of_device.h>
  15 #include <linux/gfp.h>
  16
  17 #include <asm/irq.h>
  18 #include <asm/io.h>
  19 #include <asm/dma.h>
  20
  21 #include <scsi/scsi_host.h>
  22
  23 #include "esp_scsi.h"
  24
  25 #define DRV_MODULE_NAME         "sun_esp"
  26 #define PFX DRV_MODULE_NAME     ": "
  27 #define DRV_VERSION             "1.100"
  28 #define DRV_MODULE_RELDATE      "August 27, 2008"
  29
  30 #define dma_read32(REG) \
  31         sbus_readl(esp->dma_regs + (REG))
  32 #define dma_write32(VAL, REG) \
  33         sbus_writel((VAL), esp->dma_regs + (REG))
  34
  35 /* DVMA chip revisions */
  36 enum dvma_rev {
  37         dvmarev0,
  38         dvmaesc1,
  39         dvmarev1,
  40         dvmarev2,
  41         dvmarev3,
  42         dvmarevplus,
  43         dvmahme
  44 };
  45
  46 static int esp_sbus_setup_dma(struct esp *esp, struct platform_device *dma_of)
  47 {
  48         esp->dma = dma_of;
  49
  50         esp->dma_regs = of_ioremap(&dma_of->resource[0], 0,
  51                                    resource_size(&dma_of->resource[0]),
  52                                    "espdma");
  53         if (!esp->dma_regs)
  54                 return -ENOMEM;
  55
  56         switch (dma_read32(DMA_CSR) & DMA_DEVICE_ID) {
  57         case DMA_VERS0:
  58                 esp->dmarev = dvmarev0;
  59                 break;
  60         case DMA_ESCV1:
  61                 esp->dmarev = dvmaesc1;
  62                 break;
  63         case DMA_VERS1:
  64                 esp->dmarev = dvmarev1;
  65                 break;
  66         case DMA_VERS2:
  67                 esp->dmarev = dvmarev2;
  68                 break;
  69         case DMA_VERHME:
  70                 esp->dmarev = dvmahme;
  71                 break;
  72         case DMA_VERSPLUS:
  73                 esp->dmarev = dvmarevplus;
  74                 break;
  75         }
  76
  77         return 0;
  78
  79 }
  80
  81 static int esp_sbus_map_regs(struct esp *esp, int hme)
  82 {
  83         struct platform_device *op = esp->dev;
  84         struct resource *res;
  85
  86         /* On HME, two reg sets exist, first is DVMA,
  87          * second is ESP registers.
  88          */
  89         if (hme)
  90                 res = &op->resource[1];
  91         else
  92                 res = &op->resource[0];
  93
  94         esp->regs = of_ioremap(res, 0, SBUS_ESP_REG_SIZE, "ESP");
  95         if (!esp->regs)
  96                 return -ENOMEM;
  97
  98         return 0;
  99 }
 100
 101 static int esp_sbus_map_command_block(struct esp *esp)
 102 {
 103         struct platform_device *op = esp->dev;
 104
 105         esp->command_block = dma_alloc_coherent(&op->dev, 16,
 106                                                 &esp->command_block_dma,
 107                                                 GFP_ATOMIC);
 108         if (!esp->command_block)
 109                 return -ENOMEM;
 110         return 0;
 111 }
 112
 113 static int esp_sbus_register_irq(struct esp *esp)
 114 {
 115         struct Scsi_Host *host = esp->host;
 116         struct platform_device *op = esp->dev;
 117
 118         host->irq = op->archdata.irqs[0];
 119         return request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "ESP", esp);
 120 }
 121
 122 static void esp_get_scsi_id(struct esp *esp, struct platform_device *espdma)
 123 {
 124         struct platform_device *op = esp->dev;
 125         struct device_node *dp;
 126
 127         dp = op->dev.of_node;
 128         esp->scsi_id = of_getintprop_default(dp, "initiator-id", 0xff);
 129         if (esp->scsi_id != 0xff)
 130                 goto done;
 131
 132         esp->scsi_id = of_getintprop_default(dp, "scsi-initiator-id", 0xff);
 133         if (esp->scsi_id != 0xff)
 134                 goto done;
 135
 136         esp->scsi_id = of_getintprop_default(espdma->dev.of_node,
 137                                              "scsi-initiator-id", 7);
 138
 139 done:
 140         esp->host->this_id = esp->scsi_id;
 141         esp->scsi_id_mask = (1 << esp->scsi_id);
 142 }
 143
 144 static void esp_get_differential(struct esp *esp)
 145 {
 146         struct platform_device *op = esp->dev;
 147         struct device_node *dp;
 148
 149         dp = op->dev.of_node;
 150         if (of_find_property(dp, "differential", NULL))
 151                 esp->flags |= ESP_FLAG_DIFFERENTIAL;
 152         else
 153                 esp->flags &= ~ESP_FLAG_DIFFERENTIAL;
 154 }
 155
 156 static void esp_get_clock_params(struct esp *esp)
 157 {
 158         struct platform_device *op = esp->dev;
 159         struct device_node *bus_dp, *dp;
 160         int fmhz;
 161
 162         dp = op->dev.of_node;
 163         bus_dp = dp->parent;
 164
 165         fmhz = of_getintprop_default(dp, "clock-frequency", 0);
 166         if (fmhz == 0)
 167                 fmhz = of_getintprop_default(bus_dp, "clock-frequency", 0);
 168
 169         esp->cfreq = fmhz;
 170 }
 171
 172 static void esp_get_bursts(struct esp *esp, struct platform_device *dma_of)
 173 {
 174         struct device_node *dma_dp = dma_of->dev.of_node;
 175         struct platform_device *op = esp->dev;
 176         struct device_node *dp;
 177         u8 bursts, val;
 178
 179         dp = op->dev.of_node;
 180         bursts = of_getintprop_default(dp, "burst-sizes", 0xff);
 181         val = of_getintprop_default(dma_dp, "burst-sizes", 0xff);
 182         if (val != 0xff)
 183                 bursts &= val;
 184
 185         val = of_getintprop_default(dma_dp->parent, "burst-sizes", 0xff);
 186         if (val != 0xff)
 187                 bursts &= val;
 188
 189         if (bursts == 0xff ||
 190             (bursts & DMA_BURST16) == 0 ||
 191             (bursts & DMA_BURST32) == 0)
 192                 bursts = (DMA_BURST32 - 1);
 193
 194         esp->bursts = bursts;
 195 }
 196
 197 static void esp_sbus_get_props(struct esp *esp, struct platform_device *espdma)
 198 {
 199         esp_get_scsi_id(esp, espdma);
 200         esp_get_differential(esp);
 201         esp_get_clock_params(esp);
 202         esp_get_bursts(esp, espdma);
 203 }
 204
 205 static void sbus_esp_write8(struct esp *esp, u8 val, unsigned long reg)
 206 {
 207         sbus_writeb(val, esp->regs + (reg * 4UL));
 208 }
 209
 210 static u8 sbus_esp_read8(struct esp *esp, unsigned long reg)
 211 {
 212         return sbus_readb(esp->regs + (reg * 4UL));
 213 }
 214
 215 static dma_addr_t sbus_esp_map_single(struct esp *esp, void *buf,
 216                                       size_t sz, int dir)
 217 {
 218         struct platform_device *op = esp->dev;
 219
 220         return dma_map_single(&op->dev, buf, sz, dir);
 221 }
 222
 223 static int sbus_esp_map_sg(struct esp *esp, struct scatterlist *sg,
 224                                   int num_sg, int dir)
 225 {
 226         struct platform_device *op = esp->dev;
 227
 228         return dma_map_sg(&op->dev, sg, num_sg, dir);
 229 }
 230
 231 static void sbus_esp_unmap_single(struct esp *esp, dma_addr_t addr,
 232                                   size_t sz, int dir)
 233 {
 234         struct platform_device *op = esp->dev;
 235
 236         dma_unmap_single(&op->dev, addr, sz, dir);
 237 }
 238
 239 static void sbus_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
 240                               int num_sg, int dir)
 241 {
 242         struct platform_device *op = esp->dev;
 243
 244         dma_unmap_sg(&op->dev, sg, num_sg, dir);
 245 }
 246
 247 static int sbus_esp_irq_pending(struct esp *esp)
 248 {
 249         if (dma_read32(DMA_CSR) & (DMA_HNDL_INTR | DMA_HNDL_ERROR))
 250                 return 1;
 251         return 0;
 252 }
 253
 254 static void sbus_esp_reset_dma(struct esp *esp)
 255 {
 256         int can_do_burst16, can_do_burst32, can_do_burst64;
 257         int can_do_sbus64, lim;
 258         struct platform_device *op;
 259         u32 val;
 260
 261         can_do_burst16 = (esp->bursts & DMA_BURST16) != 0;
 262         can_do_burst32 = (esp->bursts & DMA_BURST32) != 0;
 263         can_do_burst64 = 0;
 264         can_do_sbus64 = 0;
 265         op = esp->dev;
 266         if (sbus_can_dma_64bit())
 267                 can_do_sbus64 = 1;
 268         if (sbus_can_burst64())
 269                 can_do_burst64 = (esp->bursts & DMA_BURST64) != 0;
 270
 271         /* Put the DVMA into a known state. */
 272         if (esp->dmarev != dvmahme) {
 273                 val = dma_read32(DMA_CSR);
 274                 dma_write32(val | DMA_RST_SCSI, DMA_CSR);
 275                 dma_write32(val & ~DMA_RST_SCSI, DMA_CSR);
 276         }
 277         switch (esp->dmarev) {
 278         case dvmahme:
 279                 dma_write32(DMA_RESET_FAS366, DMA_CSR);
 280                 dma_write32(DMA_RST_SCSI, DMA_CSR);
 281
 282                 esp->prev_hme_dmacsr = (DMA_PARITY_OFF | DMA_2CLKS |
 283                                         DMA_SCSI_DISAB | DMA_INT_ENAB);
 284
 285                 esp->prev_hme_dmacsr &= ~(DMA_ENABLE | DMA_ST_WRITE |
 286                                           DMA_BRST_SZ);
 287
 288                 if (can_do_burst64)
 289                         esp->prev_hme_dmacsr |= DMA_BRST64;
 290                 else if (can_do_burst32)
 291                         esp->prev_hme_dmacsr |= DMA_BRST32;
 292
 293                 if (can_do_sbus64) {
 294                         esp->prev_hme_dmacsr |= DMA_SCSI_SBUS64;
 295                         sbus_set_sbus64(&op->dev, esp->bursts);
 296                 }
 297
 298                 lim = 1000;
 299                 while (dma_read32(DMA_CSR) & DMA_PEND_READ) {
 300                         if (--lim == 0) {
 301                                 printk(KERN_ALERT PFX "esp%d: DMA_PEND_READ "
 302                                        "will not clear!\n",
 303                                        esp->host->unique_id);
 304                                 break;
 305                         }
 306                         udelay(1);
 307                 }
 308
 309                 dma_write32(0, DMA_CSR);
 310                 dma_write32(esp->prev_hme_dmacsr, DMA_CSR);
 311
 312                 dma_write32(0, DMA_ADDR);
 313                 break;
 314
 315         case dvmarev2:
 316                 if (esp->rev != ESP100) {
 317                         val = dma_read32(DMA_CSR);
 318                         dma_write32(val | DMA_3CLKS, DMA_CSR);
 319                 }
 320                 break;
 321
 322         case dvmarev3:
 323                 val = dma_read32(DMA_CSR);
 324                 val &= ~DMA_3CLKS;
 325                 val |= DMA_2CLKS;
 326                 if (can_do_burst32) {
 327                         val &= ~DMA_BRST_SZ;
 328                         val |= DMA_BRST32;
 329                 }
 330                 dma_write32(val, DMA_CSR);
 331                 break;
 332
 333         case dvmaesc1:
 334                 val = dma_read32(DMA_CSR);
 335                 val |= DMA_ADD_ENABLE;
 336                 val &= ~DMA_BCNT_ENAB;
 337                 if (!can_do_burst32 && can_do_burst16) {
 338                         val |= DMA_ESC_BURST;
 339                 } else {
 340                         val &= ~(DMA_ESC_BURST);
 341                 }
 342                 dma_write32(val, DMA_CSR);
 343                 break;
 344
 345         default:
 346                 break;
 347         }
 348
 349         /* Enable interrupts.  */
 350         val = dma_read32(DMA_CSR);
 351         dma_write32(val | DMA_INT_ENAB, DMA_CSR);
 352 }
 353
 354 static void sbus_esp_dma_drain(struct esp *esp)
 355 {
 356         u32 csr;
 357         int lim;
 358
 359         if (esp->dmarev == dvmahme)
 360                 return;
 361
 362         csr = dma_read32(DMA_CSR);
 363         if (!(csr & DMA_FIFO_ISDRAIN))
 364                 return;
 365
 366         if (esp->dmarev != dvmarev3 && esp->dmarev != dvmaesc1)
 367                 dma_write32(csr | DMA_FIFO_STDRAIN, DMA_CSR);
 368
 369         lim = 1000;
 370         while (dma_read32(DMA_CSR) & DMA_FIFO_ISDRAIN) {
 371                 if (--lim == 0) {
 372                         printk(KERN_ALERT PFX "esp%d: DMA will not drain!\n",
 373                                esp->host->unique_id);
 374                         break;
 375                 }
 376                 udelay(1);
 377         }
 378 }
 379
 380 static void sbus_esp_dma_invalidate(struct esp *esp)
 381 {
 382         if (esp->dmarev == dvmahme) {
 383                 dma_write32(DMA_RST_SCSI, DMA_CSR);
 384
 385                 esp->prev_hme_dmacsr = ((esp->prev_hme_dmacsr |
 386                                          (DMA_PARITY_OFF | DMA_2CLKS |
 387                                           DMA_SCSI_DISAB | DMA_INT_ENAB)) &
 388                                         ~(DMA_ST_WRITE | DMA_ENABLE));
 389
 390                 dma_write32(0, DMA_CSR);
 391                 dma_write32(esp->prev_hme_dmacsr, DMA_CSR);
 392
 393                 /* This is necessary to avoid having the SCSI channel
 394                  * engine lock up on us.
 395                  */
 396                 dma_write32(0, DMA_ADDR);
 397         } else {
 398                 u32 val;
 399                 int lim;
 400
 401                 lim = 1000;
 402                 while ((val = dma_read32(DMA_CSR)) & DMA_PEND_READ) {
 403                         if (--lim == 0) {
 404                                 printk(KERN_ALERT PFX "esp%d: DMA will not "
 405                                        "invalidate!\n", esp->host->unique_id);
 406                                 break;
 407                         }
 408                         udelay(1);
 409                 }
 410
 411                 val &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB);
 412                 val |= DMA_FIFO_INV;
 413                 dma_write32(val, DMA_CSR);
 414                 val &= ~DMA_FIFO_INV;
 415                 dma_write32(val, DMA_CSR);
 416         }
 417 }
 418
 419 static void sbus_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
 420                                   u32 dma_count, int write, u8 cmd)
 421 {
 422         u32 csr;
 423
 424         BUG_ON(!(cmd & ESP_CMD_DMA));
 425
 426         sbus_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
 427         sbus_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
 428         if (esp->rev == FASHME) {
 429                 sbus_esp_write8(esp, (esp_count >> 16) & 0xff, FAS_RLO);
 430                 sbus_esp_write8(esp, 0, FAS_RHI);
 431
 432                 scsi_esp_cmd(esp, cmd);
 433
 434                 csr = esp->prev_hme_dmacsr;
 435                 csr |= DMA_SCSI_DISAB | DMA_ENABLE;
 436                 if (write)
 437                         csr |= DMA_ST_WRITE;
 438                 else
 439                         csr &= ~DMA_ST_WRITE;
 440                 esp->prev_hme_dmacsr = csr;
 441
 442                 dma_write32(dma_count, DMA_COUNT);
 443                 dma_write32(addr, DMA_ADDR);
 444                 dma_write32(csr, DMA_CSR);
 445         } else {
 446                 csr = dma_read32(DMA_CSR);
 447                 csr |= DMA_ENABLE;
 448                 if (write)
 449                         csr |= DMA_ST_WRITE;
 450                 else
 451                         csr &= ~DMA_ST_WRITE;
 452                 dma_write32(csr, DMA_CSR);
 453                 if (esp->dmarev == dvmaesc1) {
 454                         u32 end = PAGE_ALIGN(addr + dma_count + 16U);
 455                         dma_write32(end - addr, DMA_COUNT);
 456                 }
 457                 dma_write32(addr, DMA_ADDR);
 458
 459                 scsi_esp_cmd(esp, cmd);
 460         }
 461
 462 }
 463
 464 static int sbus_esp_dma_error(struct esp *esp)
 465 {
 466         u32 csr = dma_read32(DMA_CSR);
 467
 468         if (csr & DMA_HNDL_ERROR)
 469                 return 1;
 470
 471         return 0;
 472 }
 473
 474 static const struct esp_driver_ops sbus_esp_ops = {
 475         .esp_write8     =       sbus_esp_write8,
 476         .esp_read8      =       sbus_esp_read8,
 477         .map_single     =       sbus_esp_map_single,
 478         .map_sg         =       sbus_esp_map_sg,
 479         .unmap_single   =       sbus_esp_unmap_single,
 480         .unmap_sg       =       sbus_esp_unmap_sg,
 481         .irq_pending    =       sbus_esp_irq_pending,
 482         .reset_dma      =       sbus_esp_reset_dma,
 483         .dma_drain      =       sbus_esp_dma_drain,
 484         .dma_invalidate =       sbus_esp_dma_invalidate,
 485         .send_dma_cmd   =       sbus_esp_send_dma_cmd,
 486         .dma_error      =       sbus_esp_dma_error,
 487 };
 488
 489 static int esp_sbus_probe_one(struct platform_device *op,
 490                               struct platform_device *espdma, int hme)
 491 {
 492         struct scsi_host_template *tpnt = &scsi_esp_template;
 493         struct Scsi_Host *host;
 494         struct esp *esp;
 495         int err;
 496
 497         host = scsi_host_alloc(tpnt, sizeof(struct esp));
 498
 499         err = -ENOMEM;
 500         if (!host)
 501                 goto fail;
 502
 503         host->max_id = (hme ? 16 : 8);
 504         esp = shost_priv(host);
 505
 506         esp->host = host;
 507         esp->dev = op;
 508         esp->ops = &sbus_esp_ops;
 509
 510         if (hme)
 511                 esp->flags |= ESP_FLAG_WIDE_CAPABLE;
 512
 513         err = esp_sbus_setup_dma(esp, espdma);
 514         if (err < 0)
 515                 goto fail_unlink;
 516
 517         err = esp_sbus_map_regs(esp, hme);
 518         if (err < 0)
 519                 goto fail_unlink;
 520
 521         err = esp_sbus_map_command_block(esp);
 522         if (err < 0)
 523                 goto fail_unmap_regs;
 524
 525         err = esp_sbus_register_irq(esp);
 526         if (err < 0)
 527                 goto fail_unmap_command_block;
 528
 529         esp_sbus_get_props(esp, espdma);
 530
 531         /* Before we try to touch the ESP chip, ESC1 dma can
 532          * come up with the reset bit set, so make sure that
 533          * is clear first.
 534          */
 535         if (esp->dmarev == dvmaesc1) {
 536                 u32 val = dma_read32(DMA_CSR);
 537
 538                 dma_write32(val & ~DMA_RST_SCSI, DMA_CSR);
 539         }
 540
 541         dev_set_drvdata(&op->dev, esp);
 542
 543         err = scsi_esp_register(esp, &op->dev);
 544         if (err)
 545                 goto fail_free_irq;
 546
 547         return 0;
 548
 549 fail_free_irq:
 550         free_irq(host->irq, esp);
 551 fail_unmap_command_block:
 552         dma_free_coherent(&op->dev, 16,
 553                           esp->command_block,
 554                           esp->command_block_dma);
 555 fail_unmap_regs:
 556         of_iounmap(&op->resource[(hme ? 1 : 0)], esp->regs, SBUS_ESP_REG_SIZE);
 557 fail_unlink:
 558         scsi_host_put(host);
 559 fail:
 560         return err;
 561 }
 562
 563 static int esp_sbus_probe(struct platform_device *op)
 564 {
 565         struct device_node *dma_node = NULL;
 566         struct device_node *dp = op->dev.of_node;
 567         struct platform_device *dma_of = NULL;
 568         int hme = 0;
 569
 570         if (dp->parent &&
 571             (!strcmp(dp->parent->name, "espdma") ||
 572              !strcmp(dp->parent->name, "dma")))
 573                 dma_node = dp->parent;
 574         else if (!strcmp(dp->name, "SUNW,fas")) {
 575                 dma_node = op->dev.of_node;
 576                 hme = 1;
 577         }
 578         if (dma_node)
 579                 dma_of = of_find_device_by_node(dma_node);
 580         if (!dma_of)
 581                 return -ENODEV;
 582
 583         return esp_sbus_probe_one(op, dma_of, hme);
 584 }
 585
 586 static int esp_sbus_remove(struct platform_device *op)
 587 {
 588         struct esp *esp = dev_get_drvdata(&op->dev);
 589         struct platform_device *dma_of = esp->dma;
 590         unsigned int irq = esp->host->irq;
 591         bool is_hme;
 592         u32 val;
 593
 594         scsi_esp_unregister(esp);
 595
 596         /* Disable interrupts.  */
 597         val = dma_read32(DMA_CSR);
 598         dma_write32(val & ~DMA_INT_ENAB, DMA_CSR);
 599
 600         free_irq(irq, esp);
 601
 602         is_hme = (esp->dmarev == dvmahme);
 603
 604         dma_free_coherent(&op->dev, 16,
 605                           esp->command_block,
 606                           esp->command_block_dma);
 607         of_iounmap(&op->resource[(is_hme ? 1 : 0)], esp->regs,
 608                    SBUS_ESP_REG_SIZE);
 609         of_iounmap(&dma_of->resource[0], esp->dma_regs,
 610                    resource_size(&dma_of->resource[0]));
 611
 612         scsi_host_put(esp->host);
 613
 614         dev_set_drvdata(&op->dev, NULL);
 615
 616         return 0;
 617 }
 618
 619 static const struct of_device_id esp_match[] = {
 620         {
 621                 .name = "SUNW,esp",
 622         },
 623         {
 624                 .name = "SUNW,fas",
 625         },
 626         {
 627                 .name = "esp",
 628         },
 629         {},
 630 };
 631 MODULE_DEVICE_TABLE(of, esp_match);
 632
 633 static struct platform_driver esp_sbus_driver = {
 634         .driver = {
 635                 .name = "esp",
 636                 .of_match_table = esp_match,
 637         },
 638         .probe          = esp_sbus_probe,
 639         .remove         = esp_sbus_remove,
 640 };
 641
 642 static int __init sunesp_init(void)
 643 {
 644         return platform_driver_register(&esp_sbus_driver);
 645 }
 646
 647 static void __exit sunesp_exit(void)
 648 {
 649         platform_driver_unregister(&esp_sbus_driver);
 650 }
 651
 652 MODULE_DESCRIPTION("Sun ESP SCSI driver");
 653 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
 654 MODULE_LICENSE("GPL");
 655 MODULE_VERSION(DRV_VERSION);
 656
 657 module_init(sunesp_init);
 658 module_exit(sunesp_exit);