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 #include <linux/slab.h> 23 24 #include <asm/irq.h> 25 #include <asm/dma.h> 26 #include <asm/macints.h> 27 #include <asm/macintosh.h> 28 #include <asm/mac_via.h> 29 30 #include <scsi/scsi_host.h> 31 32 #include "esp_scsi.h" 33 34 #define DRV_MODULE_NAME "mac_esp" 35 #define PFX DRV_MODULE_NAME ": " 36 #define DRV_VERSION "1.000" 37 #define DRV_MODULE_RELDATE "Sept 15, 2007" 38 39 #define MAC_ESP_IO_BASE 0x50F00000 40 #define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000) 41 #define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000) 42 #define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000) 43 #define MAC_ESP_REGS_SPACING 0x402 44 #define MAC_ESP_PDMA_REG 0xF9800024 45 #define MAC_ESP_PDMA_REG_SPACING 0x4 46 #define MAC_ESP_PDMA_IO_OFFSET 0x100 47 48 #define esp_read8(REG) mac_esp_read8(esp, REG) 49 #define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG) 50 51 struct mac_esp_priv { 52 struct esp *esp; 53 void __iomem *pdma_regs; 54 void __iomem *pdma_io; 55 int error; 56 }; 57 static struct esp *esp_chips[2]; 58 59 #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \ 60 platform_get_drvdata((struct platform_device *) \ 61 (esp->dev))) 62 63 static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg) 64 { 65 nubus_writeb(val, esp->regs + reg * 16); 66 } 67 68 static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg) 69 { 70 return nubus_readb(esp->regs + reg * 16); 71 } 72 73 /* For pseudo DMA and PIO we need the virtual address 74 * so this address mapping is the identity mapping. 75 */ 76 77 static dma_addr_t mac_esp_map_single(struct esp *esp, void *buf, 78 size_t sz, int dir) 79 { 80 return (dma_addr_t)buf; 81 } 82 83 static int mac_esp_map_sg(struct esp *esp, struct scatterlist *sg, 84 int num_sg, int dir) 85 { 86 int i; 87 88 for (i = 0; i < num_sg; i++) 89 sg[i].dma_address = (u32)sg_virt(&sg[i]); 90 return num_sg; 91 } 92 93 static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr, 94 size_t sz, int dir) 95 { 96 /* Nothing to do. */ 97 } 98 99 static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg, 100 int num_sg, int dir) 101 { 102 /* Nothing to do. */ 103 } 104 105 static void mac_esp_reset_dma(struct esp *esp) 106 { 107 /* Nothing to do. */ 108 } 109 110 static void mac_esp_dma_drain(struct esp *esp) 111 { 112 /* Nothing to do. */ 113 } 114 115 static void mac_esp_dma_invalidate(struct esp *esp) 116 { 117 /* Nothing to do. */ 118 } 119 120 static int mac_esp_dma_error(struct esp *esp) 121 { 122 return MAC_ESP_GET_PRIV(esp)->error; 123 } 124 125 static inline int mac_esp_wait_for_empty_fifo(struct esp *esp) 126 { 127 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 128 int i = 500000; 129 130 do { 131 if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES)) 132 return 0; 133 134 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 135 return 1; 136 137 udelay(2); 138 } while (--i); 139 140 printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n", 141 esp_read8(ESP_STATUS)); 142 mep->error = 1; 143 return 1; 144 } 145 146 static inline int mac_esp_wait_for_dreq(struct esp *esp) 147 { 148 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 149 int i = 500000; 150 151 do { 152 if (mep->pdma_regs == NULL) { 153 if (via2_scsi_drq_pending()) 154 return 0; 155 } else { 156 if (nubus_readl(mep->pdma_regs) & 0x200) 157 return 0; 158 } 159 160 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 161 return 1; 162 163 udelay(2); 164 } while (--i); 165 166 printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n", 167 esp_read8(ESP_STATUS)); 168 mep->error = 1; 169 return 1; 170 } 171 172 #define MAC_ESP_PDMA_LOOP(operands) \ 173 asm volatile ( \ 174 " tstw %1 \n" \ 175 " jbeq 20f \n" \ 176 "1: movew " operands " \n" \ 177 "2: movew " operands " \n" \ 178 "3: movew " operands " \n" \ 179 "4: movew " operands " \n" \ 180 "5: movew " operands " \n" \ 181 "6: movew " operands " \n" \ 182 "7: movew " operands " \n" \ 183 "8: movew " operands " \n" \ 184 "9: movew " operands " \n" \ 185 "10: movew " operands " \n" \ 186 "11: movew " operands " \n" \ 187 "12: movew " operands " \n" \ 188 "13: movew " operands " \n" \ 189 "14: movew " operands " \n" \ 190 "15: movew " operands " \n" \ 191 "16: movew " operands " \n" \ 192 " subqw #1,%1 \n" \ 193 " jbne 1b \n" \ 194 "20: tstw %2 \n" \ 195 " jbeq 30f \n" \ 196 "21: movew " operands " \n" \ 197 " subqw #1,%2 \n" \ 198 " jbne 21b \n" \ 199 "30: tstw %3 \n" \ 200 " jbeq 40f \n" \ 201 "31: moveb " operands " \n" \ 202 "32: nop \n" \ 203 "40: \n" \ 204 " \n" \ 205 " .section __ex_table,\"a\" \n" \ 206 " .align 4 \n" \ 207 " .long 1b,40b \n" \ 208 " .long 2b,40b \n" \ 209 " .long 3b,40b \n" \ 210 " .long 4b,40b \n" \ 211 " .long 5b,40b \n" \ 212 " .long 6b,40b \n" \ 213 " .long 7b,40b \n" \ 214 " .long 8b,40b \n" \ 215 " .long 9b,40b \n" \ 216 " .long 10b,40b \n" \ 217 " .long 11b,40b \n" \ 218 " .long 12b,40b \n" \ 219 " .long 13b,40b \n" \ 220 " .long 14b,40b \n" \ 221 " .long 15b,40b \n" \ 222 " .long 16b,40b \n" \ 223 " .long 21b,40b \n" \ 224 " .long 31b,40b \n" \ 225 " .long 32b,40b \n" \ 226 " .previous \n" \ 227 : "+a" (addr), "+r" (count32), "+r" (count2) \ 228 : "g" (count1), "a" (mep->pdma_io)) 229 230 static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count, 231 u32 dma_count, int write, u8 cmd) 232 { 233 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 234 235 mep->error = 0; 236 237 if (!write) 238 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 239 240 esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW); 241 esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED); 242 243 scsi_esp_cmd(esp, cmd); 244 245 do { 246 unsigned int count32 = esp_count >> 5; 247 unsigned int count2 = (esp_count & 0x1F) >> 1; 248 unsigned int count1 = esp_count & 1; 249 unsigned int start_addr = addr; 250 251 if (mac_esp_wait_for_dreq(esp)) 252 break; 253 254 if (write) { 255 MAC_ESP_PDMA_LOOP("%4@,%0@+"); 256 257 esp_count -= addr - start_addr; 258 } else { 259 unsigned int n; 260 261 MAC_ESP_PDMA_LOOP("%0@+,%4@"); 262 263 if (mac_esp_wait_for_empty_fifo(esp)) 264 break; 265 266 n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW); 267 addr = start_addr + esp_count - n; 268 esp_count = n; 269 } 270 } while (esp_count); 271 } 272 273 /* 274 * Programmed IO routines follow. 275 */ 276 277 static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp) 278 { 279 int i = 500000; 280 281 do { 282 unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES; 283 284 if (fbytes) 285 return fbytes; 286 287 udelay(2); 288 } while (--i); 289 290 printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n", 291 esp_read8(ESP_STATUS)); 292 return 0; 293 } 294 295 static inline int mac_esp_wait_for_intr(struct esp *esp) 296 { 297 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 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 mep->error = 1; 310 return 1; 311 } 312 313 #define MAC_ESP_PIO_LOOP(operands, reg1) \ 314 asm volatile ( \ 315 "1: moveb " operands " \n" \ 316 " subqw #1,%1 \n" \ 317 " jbne 1b \n" \ 318 : "+a" (addr), "+r" (reg1) \ 319 : "a" (fifo)) 320 321 #define MAC_ESP_PIO_FILL(operands, reg1) \ 322 asm volatile ( \ 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 " moveb " operands " \n" \ 339 " subqw #8,%1 \n" \ 340 " subqw #8,%1 \n" \ 341 : "+a" (addr), "+r" (reg1) \ 342 : "a" (fifo)) 343 344 #define MAC_ESP_FIFO_SIZE 16 345 346 static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, 347 u32 dma_count, int write, u8 cmd) 348 { 349 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 350 u8 *fifo = esp->regs + ESP_FDATA * 16; 351 352 cmd &= ~ESP_CMD_DMA; 353 mep->error = 0; 354 355 if (write) { 356 scsi_esp_cmd(esp, cmd); 357 358 while (1) { 359 unsigned int n; 360 361 n = mac_esp_wait_for_fifo(esp); 362 if (!n) 363 break; 364 365 if (n > esp_count) 366 n = esp_count; 367 esp_count -= n; 368 369 MAC_ESP_PIO_LOOP("%2@,%0@+", n); 370 371 if (!esp_count) 372 break; 373 374 if (mac_esp_wait_for_intr(esp)) 375 break; 376 377 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) && 378 ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP)) 379 break; 380 381 esp->ireg = esp_read8(ESP_INTRPT); 382 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) != 383 ESP_INTR_BSERV) 384 break; 385 386 scsi_esp_cmd(esp, ESP_CMD_TI); 387 } 388 } else { 389 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 390 391 if (esp_count >= MAC_ESP_FIFO_SIZE) 392 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 393 else 394 MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count); 395 396 scsi_esp_cmd(esp, cmd); 397 398 while (esp_count) { 399 unsigned int n; 400 401 if (mac_esp_wait_for_intr(esp)) 402 break; 403 404 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) && 405 ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP)) 406 break; 407 408 esp->ireg = esp_read8(ESP_INTRPT); 409 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) != 410 ESP_INTR_BSERV) 411 break; 412 413 n = MAC_ESP_FIFO_SIZE - 414 (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES); 415 if (n > esp_count) 416 n = esp_count; 417 418 if (n == MAC_ESP_FIFO_SIZE) { 419 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 420 } else { 421 esp_count -= n; 422 MAC_ESP_PIO_LOOP("%0@+,%2@", n); 423 } 424 425 scsi_esp_cmd(esp, ESP_CMD_TI); 426 } 427 } 428 } 429 430 static int mac_esp_irq_pending(struct esp *esp) 431 { 432 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 433 return 1; 434 return 0; 435 } 436 437 static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len) 438 { 439 return dma_len > 0xFFFF ? 0xFFFF : dma_len; 440 } 441 442 static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id) 443 { 444 int got_intr; 445 446 /* 447 * This is an edge triggered IRQ, so we have to be careful to 448 * avoid missing a transition when it is shared by two ESP devices. 449 */ 450 451 do { 452 got_intr = 0; 453 if (esp_chips[0] && 454 (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) { 455 (void)scsi_esp_intr(irq, esp_chips[0]); 456 got_intr = 1; 457 } 458 if (esp_chips[1] && 459 (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) { 460 (void)scsi_esp_intr(irq, esp_chips[1]); 461 got_intr = 1; 462 } 463 } while (got_intr); 464 465 return IRQ_HANDLED; 466 } 467 468 static struct esp_driver_ops mac_esp_ops = { 469 .esp_write8 = mac_esp_write8, 470 .esp_read8 = mac_esp_read8, 471 .map_single = mac_esp_map_single, 472 .map_sg = mac_esp_map_sg, 473 .unmap_single = mac_esp_unmap_single, 474 .unmap_sg = mac_esp_unmap_sg, 475 .irq_pending = mac_esp_irq_pending, 476 .dma_length_limit = mac_esp_dma_length_limit, 477 .reset_dma = mac_esp_reset_dma, 478 .dma_drain = mac_esp_dma_drain, 479 .dma_invalidate = mac_esp_dma_invalidate, 480 .send_dma_cmd = mac_esp_send_pdma_cmd, 481 .dma_error = mac_esp_dma_error, 482 }; 483 484 static int esp_mac_probe(struct platform_device *dev) 485 { 486 struct scsi_host_template *tpnt = &scsi_esp_template; 487 struct Scsi_Host *host; 488 struct esp *esp; 489 int err; 490 struct mac_esp_priv *mep; 491 492 if (!MACH_IS_MAC) 493 return -ENODEV; 494 495 if (dev->id > 1) 496 return -ENODEV; 497 498 host = scsi_host_alloc(tpnt, sizeof(struct esp)); 499 500 err = -ENOMEM; 501 if (!host) 502 goto fail; 503 504 host->max_id = 8; 505 host->use_clustering = DISABLE_CLUSTERING; 506 esp = shost_priv(host); 507 508 esp->host = host; 509 esp->dev = dev; 510 511 esp->command_block = kzalloc(16, GFP_KERNEL); 512 if (!esp->command_block) 513 goto fail_unlink; 514 esp->command_block_dma = (dma_addr_t)esp->command_block; 515 516 esp->scsi_id = 7; 517 host->this_id = esp->scsi_id; 518 esp->scsi_id_mask = 1 << esp->scsi_id; 519 520 mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL); 521 if (!mep) 522 goto fail_free_command_block; 523 mep->esp = esp; 524 platform_set_drvdata(dev, mep); 525 526 switch (macintosh_config->scsi_type) { 527 case MAC_SCSI_QUADRA: 528 esp->cfreq = 16500000; 529 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA; 530 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 531 mep->pdma_regs = NULL; 532 break; 533 case MAC_SCSI_QUADRA2: 534 esp->cfreq = 25000000; 535 esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 + 536 dev->id * MAC_ESP_REGS_SPACING); 537 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 538 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG + 539 dev->id * MAC_ESP_PDMA_REG_SPACING); 540 nubus_writel(0x1d1, mep->pdma_regs); 541 break; 542 case MAC_SCSI_QUADRA3: 543 /* These quadras have a real DMA controller (the PSC) but we 544 * don't know how to drive it so we must use PIO instead. 545 */ 546 esp->cfreq = 25000000; 547 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3; 548 mep->pdma_io = NULL; 549 mep->pdma_regs = NULL; 550 break; 551 } 552 553 esp->ops = &mac_esp_ops; 554 if (mep->pdma_io == NULL) { 555 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id); 556 esp_write8(0, ESP_TCLOW); 557 esp_write8(0, ESP_TCMED); 558 esp->flags = ESP_FLAG_DISABLE_SYNC; 559 mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd; 560 } else { 561 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id); 562 } 563 564 host->irq = IRQ_MAC_SCSI; 565 esp_chips[dev->id] = esp; 566 mb(); 567 if (esp_chips[!dev->id] == NULL) { 568 err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL); 569 if (err < 0) { 570 esp_chips[dev->id] = NULL; 571 goto fail_free_priv; 572 } 573 } 574 575 err = scsi_esp_register(esp, &dev->dev); 576 if (err) 577 goto fail_free_irq; 578 579 return 0; 580 581 fail_free_irq: 582 if (esp_chips[!dev->id] == NULL) 583 free_irq(host->irq, esp); 584 fail_free_priv: 585 kfree(mep); 586 fail_free_command_block: 587 kfree(esp->command_block); 588 fail_unlink: 589 scsi_host_put(host); 590 fail: 591 return err; 592 } 593 594 static int esp_mac_remove(struct platform_device *dev) 595 { 596 struct mac_esp_priv *mep = platform_get_drvdata(dev); 597 struct esp *esp = mep->esp; 598 unsigned int irq = esp->host->irq; 599 600 scsi_esp_unregister(esp); 601 602 esp_chips[dev->id] = NULL; 603 if (!(esp_chips[0] || esp_chips[1])) 604 free_irq(irq, NULL); 605 606 kfree(mep); 607 608 kfree(esp->command_block); 609 610 scsi_host_put(esp->host); 611 612 return 0; 613 } 614 615 static struct platform_driver esp_mac_driver = { 616 .probe = esp_mac_probe, 617 .remove = esp_mac_remove, 618 .driver = { 619 .name = DRV_MODULE_NAME, 620 .owner = THIS_MODULE, 621 }, 622 }; 623 624 static int __init mac_esp_init(void) 625 { 626 return platform_driver_register(&esp_mac_driver); 627 } 628 629 static void __exit mac_esp_exit(void) 630 { 631 platform_driver_unregister(&esp_mac_driver); 632 } 633 634 MODULE_DESCRIPTION("Mac ESP SCSI driver"); 635 MODULE_AUTHOR("Finn Thain <fthain@telegraphics.com.au>"); 636 MODULE_LICENSE("GPL v2"); 637 MODULE_VERSION(DRV_VERSION); 638 MODULE_ALIAS("platform:" DRV_MODULE_NAME); 639 640 module_init(mac_esp_init); 641 module_exit(mac_esp_exit); 642