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 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 esp *esp_chips[2]; 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 %1 \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,%1 \n" \ 192 " jbne 1b \n" \ 193 "20: tstw %2 \n" \ 194 " jbeq 30f \n" \ 195 "21: movew " operands " \n" \ 196 " subqw #1,%2 \n" \ 197 " jbne 21b \n" \ 198 "30: tstw %3 \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), "+r" (count32), "+r" (count2) \ 227 : "g" (count1), "a" (mep->pdma_io)) 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); 233 234 mep->error = 0; 235 236 if (!write) 237 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 238 239 esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW); 240 esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED); 241 242 scsi_esp_cmd(esp, cmd); 243 244 do { 245 unsigned int count32 = esp_count >> 5; 246 unsigned int count2 = (esp_count & 0x1F) >> 1; 247 unsigned int count1 = esp_count & 1; 248 unsigned int start_addr = addr; 249 250 if (mac_esp_wait_for_dreq(esp)) 251 break; 252 253 if (write) { 254 MAC_ESP_PDMA_LOOP("%4@,%0@+"); 255 256 esp_count -= addr - start_addr; 257 } else { 258 unsigned int n; 259 260 MAC_ESP_PDMA_LOOP("%0@+,%4@"); 261 262 if (mac_esp_wait_for_empty_fifo(esp)) 263 break; 264 265 n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW); 266 addr = start_addr + esp_count - n; 267 esp_count = n; 268 } 269 } while (esp_count); 270 } 271 272 /* 273 * Programmed IO routines follow. 274 */ 275 276 static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp) 277 { 278 int i = 500000; 279 280 do { 281 unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES; 282 283 if (fbytes) 284 return fbytes; 285 286 udelay(2); 287 } while (--i); 288 289 printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n", 290 esp_read8(ESP_STATUS)); 291 return 0; 292 } 293 294 static inline int mac_esp_wait_for_intr(struct esp *esp) 295 { 296 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 297 int i = 500000; 298 299 do { 300 esp->sreg = esp_read8(ESP_STATUS); 301 if (esp->sreg & ESP_STAT_INTR) 302 return 0; 303 304 udelay(2); 305 } while (--i); 306 307 printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg); 308 mep->error = 1; 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 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 349 u8 *fifo = esp->regs + ESP_FDATA * 16; 350 351 cmd &= ~ESP_CMD_DMA; 352 mep->error = 0; 353 354 if (write) { 355 scsi_esp_cmd(esp, cmd); 356 357 while (1) { 358 unsigned int n; 359 360 n = mac_esp_wait_for_fifo(esp); 361 if (!n) 362 break; 363 364 if (n > esp_count) 365 n = esp_count; 366 esp_count -= n; 367 368 MAC_ESP_PIO_LOOP("%2@,%0@+", n); 369 370 if (!esp_count) 371 break; 372 373 if (mac_esp_wait_for_intr(esp)) 374 break; 375 376 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) && 377 ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP)) 378 break; 379 380 esp->ireg = esp_read8(ESP_INTRPT); 381 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) != 382 ESP_INTR_BSERV) 383 break; 384 385 scsi_esp_cmd(esp, ESP_CMD_TI); 386 } 387 } else { 388 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 389 390 if (esp_count >= MAC_ESP_FIFO_SIZE) 391 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 392 else 393 MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count); 394 395 scsi_esp_cmd(esp, cmd); 396 397 while (esp_count) { 398 unsigned int n; 399 400 if (mac_esp_wait_for_intr(esp)) 401 break; 402 403 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) && 404 ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP)) 405 break; 406 407 esp->ireg = esp_read8(ESP_INTRPT); 408 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) != 409 ESP_INTR_BSERV) 410 break; 411 412 n = MAC_ESP_FIFO_SIZE - 413 (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES); 414 if (n > esp_count) 415 n = esp_count; 416 417 if (n == MAC_ESP_FIFO_SIZE) { 418 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 419 } else { 420 esp_count -= n; 421 MAC_ESP_PIO_LOOP("%0@+,%2@", n); 422 } 423 424 scsi_esp_cmd(esp, ESP_CMD_TI); 425 } 426 } 427 } 428 429 static int mac_esp_irq_pending(struct esp *esp) 430 { 431 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 432 return 1; 433 return 0; 434 } 435 436 static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len) 437 { 438 return dma_len > 0xFFFF ? 0xFFFF : dma_len; 439 } 440 441 static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id) 442 { 443 int got_intr; 444 445 /* 446 * This is an edge triggered IRQ, so we have to be careful to 447 * avoid missing a transition when it is shared by two ESP devices. 448 */ 449 450 do { 451 got_intr = 0; 452 if (esp_chips[0] && 453 (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) { 454 (void)scsi_esp_intr(irq, esp_chips[0]); 455 got_intr = 1; 456 } 457 if (esp_chips[1] && 458 (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) { 459 (void)scsi_esp_intr(irq, esp_chips[1]); 460 got_intr = 1; 461 } 462 } while (got_intr); 463 464 return IRQ_HANDLED; 465 } 466 467 static struct esp_driver_ops mac_esp_ops = { 468 .esp_write8 = mac_esp_write8, 469 .esp_read8 = mac_esp_read8, 470 .map_single = mac_esp_map_single, 471 .map_sg = mac_esp_map_sg, 472 .unmap_single = mac_esp_unmap_single, 473 .unmap_sg = mac_esp_unmap_sg, 474 .irq_pending = mac_esp_irq_pending, 475 .dma_length_limit = mac_esp_dma_length_limit, 476 .reset_dma = mac_esp_reset_dma, 477 .dma_drain = mac_esp_dma_drain, 478 .dma_invalidate = mac_esp_dma_invalidate, 479 .send_dma_cmd = mac_esp_send_pdma_cmd, 480 .dma_error = mac_esp_dma_error, 481 }; 482 483 static int __devinit esp_mac_probe(struct platform_device *dev) 484 { 485 struct scsi_host_template *tpnt = &scsi_esp_template; 486 struct Scsi_Host *host; 487 struct esp *esp; 488 int err; 489 struct mac_esp_priv *mep; 490 491 if (!MACH_IS_MAC) 492 return -ENODEV; 493 494 if (dev->id > 1) 495 return -ENODEV; 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 = 8; 504 host->use_clustering = DISABLE_CLUSTERING; 505 esp = shost_priv(host); 506 507 esp->host = host; 508 esp->dev = dev; 509 510 esp->command_block = kzalloc(16, GFP_KERNEL); 511 if (!esp->command_block) 512 goto fail_unlink; 513 esp->command_block_dma = (dma_addr_t)esp->command_block; 514 515 esp->scsi_id = 7; 516 host->this_id = esp->scsi_id; 517 esp->scsi_id_mask = 1 << esp->scsi_id; 518 519 mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL); 520 if (!mep) 521 goto fail_free_command_block; 522 mep->esp = esp; 523 platform_set_drvdata(dev, mep); 524 525 switch (macintosh_config->scsi_type) { 526 case MAC_SCSI_QUADRA: 527 esp->cfreq = 16500000; 528 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA; 529 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 530 mep->pdma_regs = NULL; 531 break; 532 case MAC_SCSI_QUADRA2: 533 esp->cfreq = 25000000; 534 esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 + 535 dev->id * MAC_ESP_REGS_SPACING); 536 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 537 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG + 538 dev->id * MAC_ESP_PDMA_REG_SPACING); 539 nubus_writel(0x1d1, mep->pdma_regs); 540 break; 541 case MAC_SCSI_QUADRA3: 542 /* These quadras have a real DMA controller (the PSC) but we 543 * don't know how to drive it so we must use PIO instead. 544 */ 545 esp->cfreq = 25000000; 546 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3; 547 mep->pdma_io = NULL; 548 mep->pdma_regs = NULL; 549 break; 550 } 551 552 esp->ops = &mac_esp_ops; 553 if (mep->pdma_io == NULL) { 554 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id); 555 esp_write8(0, ESP_TCLOW); 556 esp_write8(0, ESP_TCMED); 557 esp->flags = ESP_FLAG_DISABLE_SYNC; 558 mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd; 559 } else { 560 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id); 561 } 562 563 host->irq = IRQ_MAC_SCSI; 564 esp_chips[dev->id] = esp; 565 mb(); 566 if (esp_chips[!dev->id] == NULL) { 567 err = request_irq(host->irq, mac_scsi_esp_intr, 0, 568 "Mac 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 __devexit 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 = __devexit_p(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