1 /* mac_esp.c: ESP front-end for Macintosh Quadra systems. 2 * 3 * Adapted from jazz_esp.c and the old mac_esp.c. 4 * 5 * The pseudo DMA algorithm is based on the one used in NetBSD. 6 * See sys/arch/mac68k/obio/esp.c for some background information. 7 * 8 * Copyright (C) 2007-2008 Finn Thain 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/types.h> 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/interrupt.h> 16 #include <linux/platform_device.h> 17 #include <linux/dma-mapping.h> 18 #include <linux/scatterlist.h> 19 #include <linux/delay.h> 20 #include <linux/io.h> 21 #include <linux/nubus.h> 22 23 #include <asm/irq.h> 24 #include <asm/dma.h> 25 26 #include <asm/macints.h> 27 #include <asm/macintosh.h> 28 29 #include <scsi/scsi_host.h> 30 31 #include "esp_scsi.h" 32 33 #define DRV_MODULE_NAME "mac_esp" 34 #define PFX DRV_MODULE_NAME ": " 35 #define DRV_VERSION "1.000" 36 #define DRV_MODULE_RELDATE "Sept 15, 2007" 37 38 #define MAC_ESP_IO_BASE 0x50F00000 39 #define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000) 40 #define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000) 41 #define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000) 42 #define MAC_ESP_REGS_SPACING 0x402 43 #define MAC_ESP_PDMA_REG 0xF9800024 44 #define MAC_ESP_PDMA_REG_SPACING 0x4 45 #define MAC_ESP_PDMA_IO_OFFSET 0x100 46 47 #define esp_read8(REG) mac_esp_read8(esp, REG) 48 #define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG) 49 50 struct mac_esp_priv { 51 struct esp *esp; 52 void __iomem *pdma_regs; 53 void __iomem *pdma_io; 54 int error; 55 }; 56 static struct platform_device *internal_esp, *external_esp; 57 58 #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \ 59 platform_get_drvdata((struct platform_device *) \ 60 (esp->dev))) 61 62 static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg) 63 { 64 nubus_writeb(val, esp->regs + reg * 16); 65 } 66 67 static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg) 68 { 69 return nubus_readb(esp->regs + reg * 16); 70 } 71 72 /* For pseudo DMA and PIO we need the virtual address 73 * so this address mapping is the identity mapping. 74 */ 75 76 static dma_addr_t mac_esp_map_single(struct esp *esp, void *buf, 77 size_t sz, int dir) 78 { 79 return (dma_addr_t)buf; 80 } 81 82 static int mac_esp_map_sg(struct esp *esp, struct scatterlist *sg, 83 int num_sg, int dir) 84 { 85 int i; 86 87 for (i = 0; i < num_sg; i++) 88 sg[i].dma_address = (u32)sg_virt(&sg[i]); 89 return num_sg; 90 } 91 92 static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr, 93 size_t sz, int dir) 94 { 95 /* Nothing to do. */ 96 } 97 98 static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg, 99 int num_sg, int dir) 100 { 101 /* Nothing to do. */ 102 } 103 104 static void mac_esp_reset_dma(struct esp *esp) 105 { 106 /* Nothing to do. */ 107 } 108 109 static void mac_esp_dma_drain(struct esp *esp) 110 { 111 /* Nothing to do. */ 112 } 113 114 static void mac_esp_dma_invalidate(struct esp *esp) 115 { 116 /* Nothing to do. */ 117 } 118 119 static int mac_esp_dma_error(struct esp *esp) 120 { 121 return MAC_ESP_GET_PRIV(esp)->error; 122 } 123 124 static inline int mac_esp_wait_for_empty_fifo(struct esp *esp) 125 { 126 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 127 int i = 500000; 128 129 do { 130 if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES)) 131 return 0; 132 133 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 134 return 1; 135 136 udelay(2); 137 } while (--i); 138 139 printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n", 140 esp_read8(ESP_STATUS)); 141 mep->error = 1; 142 return 1; 143 } 144 145 static inline int mac_esp_wait_for_dreq(struct esp *esp) 146 { 147 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 148 int i = 500000; 149 150 do { 151 if (mep->pdma_regs == NULL) { 152 if (mac_irq_pending(IRQ_MAC_SCSIDRQ)) 153 return 0; 154 } else { 155 if (nubus_readl(mep->pdma_regs) & 0x200) 156 return 0; 157 } 158 159 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 160 return 1; 161 162 udelay(2); 163 } while (--i); 164 165 printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n", 166 esp_read8(ESP_STATUS)); 167 mep->error = 1; 168 return 1; 169 } 170 171 #define MAC_ESP_PDMA_LOOP(operands) \ 172 asm volatile ( \ 173 " tstw %2 \n" \ 174 " jbeq 20f \n" \ 175 "1: movew " operands " \n" \ 176 "2: movew " operands " \n" \ 177 "3: movew " operands " \n" \ 178 "4: movew " operands " \n" \ 179 "5: movew " operands " \n" \ 180 "6: movew " operands " \n" \ 181 "7: movew " operands " \n" \ 182 "8: movew " operands " \n" \ 183 "9: movew " operands " \n" \ 184 "10: movew " operands " \n" \ 185 "11: movew " operands " \n" \ 186 "12: movew " operands " \n" \ 187 "13: movew " operands " \n" \ 188 "14: movew " operands " \n" \ 189 "15: movew " operands " \n" \ 190 "16: movew " operands " \n" \ 191 " subqw #1,%2 \n" \ 192 " jbne 1b \n" \ 193 "20: tstw %3 \n" \ 194 " jbeq 30f \n" \ 195 "21: movew " operands " \n" \ 196 " subqw #1,%3 \n" \ 197 " jbne 21b \n" \ 198 "30: tstw %4 \n" \ 199 " jbeq 40f \n" \ 200 "31: moveb " operands " \n" \ 201 "32: nop \n" \ 202 "40: \n" \ 203 " \n" \ 204 " .section __ex_table,\"a\" \n" \ 205 " .align 4 \n" \ 206 " .long 1b,40b \n" \ 207 " .long 2b,40b \n" \ 208 " .long 3b,40b \n" \ 209 " .long 4b,40b \n" \ 210 " .long 5b,40b \n" \ 211 " .long 6b,40b \n" \ 212 " .long 7b,40b \n" \ 213 " .long 8b,40b \n" \ 214 " .long 9b,40b \n" \ 215 " .long 10b,40b \n" \ 216 " .long 11b,40b \n" \ 217 " .long 12b,40b \n" \ 218 " .long 13b,40b \n" \ 219 " .long 14b,40b \n" \ 220 " .long 15b,40b \n" \ 221 " .long 16b,40b \n" \ 222 " .long 21b,40b \n" \ 223 " .long 31b,40b \n" \ 224 " .long 32b,40b \n" \ 225 " .previous \n" \ 226 : "+a" (addr) \ 227 : "a" (mep->pdma_io), "r" (count32), "r" (count2), "g" (esp_count)) 228 229 static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count, 230 u32 dma_count, int write, u8 cmd) 231 { 232 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 233 unsigned long flags; 234 235 local_irq_save(flags); 236 237 mep->error = 0; 238 239 if (!write) 240 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 241 242 esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW); 243 esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED); 244 245 scsi_esp_cmd(esp, cmd); 246 247 do { 248 unsigned int count32 = esp_count >> 5; 249 unsigned int count2 = (esp_count & 0x1F) >> 1; 250 unsigned int start_addr = addr; 251 252 if (mac_esp_wait_for_dreq(esp)) 253 break; 254 255 if (write) { 256 MAC_ESP_PDMA_LOOP("%1@,%0@+"); 257 258 esp_count -= addr - start_addr; 259 } else { 260 unsigned int n; 261 262 MAC_ESP_PDMA_LOOP("%0@+,%1@"); 263 264 if (mac_esp_wait_for_empty_fifo(esp)) 265 break; 266 267 n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW); 268 addr = start_addr + esp_count - n; 269 esp_count = n; 270 } 271 } while (esp_count); 272 273 local_irq_restore(flags); 274 } 275 276 /* 277 * Programmed IO routines follow. 278 */ 279 280 static inline int mac_esp_wait_for_fifo(struct esp *esp) 281 { 282 int i = 500000; 283 284 do { 285 if (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES) 286 return 0; 287 288 udelay(2); 289 } while (--i); 290 291 printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n", 292 esp_read8(ESP_STATUS)); 293 return 1; 294 } 295 296 static inline int mac_esp_wait_for_intr(struct esp *esp) 297 { 298 int i = 500000; 299 300 do { 301 esp->sreg = esp_read8(ESP_STATUS); 302 if (esp->sreg & ESP_STAT_INTR) 303 return 0; 304 305 udelay(2); 306 } while (--i); 307 308 printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg); 309 return 1; 310 } 311 312 #define MAC_ESP_PIO_LOOP(operands, reg1) \ 313 asm volatile ( \ 314 "1: moveb " operands " \n" \ 315 " subqw #1,%1 \n" \ 316 " jbne 1b \n" \ 317 : "+a" (addr), "+r" (reg1) \ 318 : "a" (fifo)) 319 320 #define MAC_ESP_PIO_FILL(operands, reg1) \ 321 asm volatile ( \ 322 " moveb " operands " \n" \ 323 " moveb " operands " \n" \ 324 " moveb " operands " \n" \ 325 " moveb " operands " \n" \ 326 " moveb " operands " \n" \ 327 " moveb " operands " \n" \ 328 " moveb " operands " \n" \ 329 " moveb " operands " \n" \ 330 " moveb " operands " \n" \ 331 " moveb " operands " \n" \ 332 " moveb " operands " \n" \ 333 " moveb " operands " \n" \ 334 " moveb " operands " \n" \ 335 " moveb " operands " \n" \ 336 " moveb " operands " \n" \ 337 " moveb " operands " \n" \ 338 " subqw #8,%1 \n" \ 339 " subqw #8,%1 \n" \ 340 : "+a" (addr), "+r" (reg1) \ 341 : "a" (fifo)) 342 343 #define MAC_ESP_FIFO_SIZE 16 344 345 static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, 346 u32 dma_count, int write, u8 cmd) 347 { 348 unsigned long flags; 349 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 350 u8 *fifo = esp->regs + ESP_FDATA * 16; 351 352 local_irq_save(flags); 353 354 cmd &= ~ESP_CMD_DMA; 355 mep->error = 0; 356 357 if (write) { 358 scsi_esp_cmd(esp, cmd); 359 360 if (!mac_esp_wait_for_intr(esp)) { 361 if (mac_esp_wait_for_fifo(esp)) 362 esp_count = 0; 363 } else { 364 esp_count = 0; 365 } 366 } else { 367 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 368 369 if (esp_count >= MAC_ESP_FIFO_SIZE) 370 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 371 else 372 MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count); 373 374 scsi_esp_cmd(esp, cmd); 375 } 376 377 while (esp_count) { 378 unsigned int n; 379 380 if (mac_esp_wait_for_intr(esp)) { 381 mep->error = 1; 382 break; 383 } 384 385 if (esp->sreg & ESP_STAT_SPAM) { 386 printk(KERN_ERR PFX "gross error\n"); 387 mep->error = 1; 388 break; 389 } 390 391 n = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES; 392 393 if (write) { 394 if (n > esp_count) 395 n = esp_count; 396 esp_count -= n; 397 398 MAC_ESP_PIO_LOOP("%2@,%0@+", n); 399 400 if ((esp->sreg & ESP_STAT_PMASK) == ESP_STATP) 401 break; 402 403 if (esp_count) { 404 esp->ireg = esp_read8(ESP_INTRPT); 405 if (esp->ireg & ESP_INTR_DC) 406 break; 407 408 scsi_esp_cmd(esp, ESP_CMD_TI); 409 } 410 } else { 411 esp->ireg = esp_read8(ESP_INTRPT); 412 if (esp->ireg & ESP_INTR_DC) 413 break; 414 415 n = MAC_ESP_FIFO_SIZE - n; 416 if (n > esp_count) 417 n = esp_count; 418 419 if (n == MAC_ESP_FIFO_SIZE) { 420 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 421 } else { 422 esp_count -= n; 423 MAC_ESP_PIO_LOOP("%0@+,%2@", n); 424 } 425 426 scsi_esp_cmd(esp, ESP_CMD_TI); 427 } 428 } 429 430 local_irq_restore(flags); 431 } 432 433 static int mac_esp_irq_pending(struct esp *esp) 434 { 435 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 436 return 1; 437 return 0; 438 } 439 440 static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len) 441 { 442 return dma_len > 0xFFFF ? 0xFFFF : dma_len; 443 } 444 445 static struct esp_driver_ops mac_esp_ops = { 446 .esp_write8 = mac_esp_write8, 447 .esp_read8 = mac_esp_read8, 448 .map_single = mac_esp_map_single, 449 .map_sg = mac_esp_map_sg, 450 .unmap_single = mac_esp_unmap_single, 451 .unmap_sg = mac_esp_unmap_sg, 452 .irq_pending = mac_esp_irq_pending, 453 .dma_length_limit = mac_esp_dma_length_limit, 454 .reset_dma = mac_esp_reset_dma, 455 .dma_drain = mac_esp_dma_drain, 456 .dma_invalidate = mac_esp_dma_invalidate, 457 .send_dma_cmd = mac_esp_send_pdma_cmd, 458 .dma_error = mac_esp_dma_error, 459 }; 460 461 static int __devinit esp_mac_probe(struct platform_device *dev) 462 { 463 struct scsi_host_template *tpnt = &scsi_esp_template; 464 struct Scsi_Host *host; 465 struct esp *esp; 466 int err; 467 int chips_present; 468 struct mac_esp_priv *mep; 469 470 if (!MACH_IS_MAC) 471 return -ENODEV; 472 473 switch (macintosh_config->scsi_type) { 474 case MAC_SCSI_QUADRA: 475 case MAC_SCSI_QUADRA3: 476 chips_present = 1; 477 break; 478 case MAC_SCSI_QUADRA2: 479 if ((macintosh_config->ident == MAC_MODEL_Q900) || 480 (macintosh_config->ident == MAC_MODEL_Q950)) 481 chips_present = 2; 482 else 483 chips_present = 1; 484 break; 485 default: 486 chips_present = 0; 487 } 488 489 if (dev->id + 1 > chips_present) 490 return -ENODEV; 491 492 host = scsi_host_alloc(tpnt, sizeof(struct esp)); 493 494 err = -ENOMEM; 495 if (!host) 496 goto fail; 497 498 host->max_id = 8; 499 host->use_clustering = DISABLE_CLUSTERING; 500 esp = shost_priv(host); 501 502 esp->host = host; 503 esp->dev = dev; 504 505 esp->command_block = kzalloc(16, GFP_KERNEL); 506 if (!esp->command_block) 507 goto fail_unlink; 508 esp->command_block_dma = (dma_addr_t)esp->command_block; 509 510 esp->scsi_id = 7; 511 host->this_id = esp->scsi_id; 512 esp->scsi_id_mask = 1 << esp->scsi_id; 513 514 mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL); 515 if (!mep) 516 goto fail_free_command_block; 517 mep->esp = esp; 518 platform_set_drvdata(dev, mep); 519 520 switch (macintosh_config->scsi_type) { 521 case MAC_SCSI_QUADRA: 522 esp->cfreq = 16500000; 523 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA; 524 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 525 mep->pdma_regs = NULL; 526 break; 527 case MAC_SCSI_QUADRA2: 528 esp->cfreq = 25000000; 529 esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 + 530 dev->id * MAC_ESP_REGS_SPACING); 531 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 532 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG + 533 dev->id * MAC_ESP_PDMA_REG_SPACING); 534 nubus_writel(0x1d1, mep->pdma_regs); 535 break; 536 case MAC_SCSI_QUADRA3: 537 /* These quadras have a real DMA controller (the PSC) but we 538 * don't know how to drive it so we must use PIO instead. 539 */ 540 esp->cfreq = 25000000; 541 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3; 542 mep->pdma_io = NULL; 543 mep->pdma_regs = NULL; 544 break; 545 } 546 547 esp->ops = &mac_esp_ops; 548 if (mep->pdma_io == NULL) { 549 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id); 550 esp_write8(0, ESP_TCLOW); 551 esp_write8(0, ESP_TCMED); 552 esp->flags = ESP_FLAG_DISABLE_SYNC; 553 mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd; 554 } else { 555 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id); 556 } 557 558 host->irq = IRQ_MAC_SCSI; 559 err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "Mac ESP", 560 esp); 561 if (err < 0) 562 goto fail_free_priv; 563 564 err = scsi_esp_register(esp, &dev->dev); 565 if (err) 566 goto fail_free_irq; 567 568 return 0; 569 570 fail_free_irq: 571 free_irq(host->irq, esp); 572 fail_free_priv: 573 kfree(mep); 574 fail_free_command_block: 575 kfree(esp->command_block); 576 fail_unlink: 577 scsi_host_put(host); 578 fail: 579 return err; 580 } 581 582 static int __devexit esp_mac_remove(struct platform_device *dev) 583 { 584 struct mac_esp_priv *mep = platform_get_drvdata(dev); 585 struct esp *esp = mep->esp; 586 unsigned int irq = esp->host->irq; 587 588 scsi_esp_unregister(esp); 589 590 free_irq(irq, esp); 591 592 kfree(mep); 593 594 kfree(esp->command_block); 595 596 scsi_host_put(esp->host); 597 598 return 0; 599 } 600 601 static struct platform_driver esp_mac_driver = { 602 .probe = esp_mac_probe, 603 .remove = __devexit_p(esp_mac_remove), 604 .driver = { 605 .name = DRV_MODULE_NAME, 606 }, 607 }; 608 609 static int __init mac_esp_init(void) 610 { 611 int err; 612 613 err = platform_driver_register(&esp_mac_driver); 614 if (err) 615 return err; 616 617 internal_esp = platform_device_alloc(DRV_MODULE_NAME, 0); 618 if (internal_esp && platform_device_add(internal_esp)) { 619 platform_device_put(internal_esp); 620 internal_esp = NULL; 621 } 622 623 external_esp = platform_device_alloc(DRV_MODULE_NAME, 1); 624 if (external_esp && platform_device_add(external_esp)) { 625 platform_device_put(external_esp); 626 external_esp = NULL; 627 } 628 629 if (internal_esp || external_esp) { 630 return 0; 631 } else { 632 platform_driver_unregister(&esp_mac_driver); 633 return -ENOMEM; 634 } 635 } 636 637 static void __exit mac_esp_exit(void) 638 { 639 platform_driver_unregister(&esp_mac_driver); 640 641 if (internal_esp) { 642 platform_device_unregister(internal_esp); 643 internal_esp = NULL; 644 } 645 if (external_esp) { 646 platform_device_unregister(external_esp); 647 external_esp = NULL; 648 } 649 } 650 651 MODULE_DESCRIPTION("Mac ESP SCSI driver"); 652 MODULE_AUTHOR("Finn Thain <fthain@telegraphics.com.au>"); 653 MODULE_LICENSE("GPLv2"); 654 MODULE_VERSION(DRV_VERSION); 655 656 module_init(mac_esp_init); 657 module_exit(mac_esp_exit); 658