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 50struct mac_esp_priv { 51 struct esp *esp; 52 void __iomem *pdma_regs; 53 void __iomem *pdma_io; 54 int error; 55}; 56static 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 62static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg) 63{ 64 nubus_writeb(val, esp->regs + reg * 16); 65} 66 67static 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 76static 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 82static 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 92static 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 98static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg, 99 int num_sg, int dir) 100{ 101 /* Nothing to do. */ 102} 103 104static void mac_esp_reset_dma(struct esp *esp) 105{ 106 /* Nothing to do. */ 107} 108 109static void mac_esp_dma_drain(struct esp *esp) 110{ 111 /* Nothing to do. */ 112} 113 114static void mac_esp_dma_invalidate(struct esp *esp) 115{ 116 /* Nothing to do. */ 117} 118 119static int mac_esp_dma_error(struct esp *esp) 120{ 121 return MAC_ESP_GET_PRIV(esp)->error; 122} 123 124static 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 145static 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 229static 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 count1 = esp_count & 1; 251 unsigned int start_addr = addr; 252 253 if (mac_esp_wait_for_dreq(esp)) 254 break; 255 256 if (write) { 257 MAC_ESP_PDMA_LOOP("%4@,%0@+"); 258 259 esp_count -= addr - start_addr; 260 } else { 261 unsigned int n; 262 263 MAC_ESP_PDMA_LOOP("%0@+,%4@"); 264 265 if (mac_esp_wait_for_empty_fifo(esp)) 266 break; 267 268 n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW); 269 addr = start_addr + esp_count - n; 270 esp_count = n; 271 } 272 } while (esp_count); 273 274 local_irq_restore(flags); 275} 276 277/* 278 * Programmed IO routines follow. 279 */ 280 281static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp) 282{ 283 int i = 500000; 284 285 do { 286 unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES; 287 288 if (fbytes) 289 return fbytes; 290 291 udelay(2); 292 } while (--i); 293 294 printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n", 295 esp_read8(ESP_STATUS)); 296 return 0; 297} 298 299static inline int mac_esp_wait_for_intr(struct esp *esp) 300{ 301 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 302 int i = 500000; 303 304 do { 305 esp->sreg = esp_read8(ESP_STATUS); 306 if (esp->sreg & ESP_STAT_INTR) 307 return 0; 308 309 udelay(2); 310 } while (--i); 311 312 printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg); 313 mep->error = 1; 314 return 1; 315} 316 317#define MAC_ESP_PIO_LOOP(operands, reg1) \ 318 asm volatile ( \ 319 "1: moveb " operands " \n" \ 320 " subqw #1,%1 \n" \ 321 " jbne 1b \n" \ 322 : "+a" (addr), "+r" (reg1) \ 323 : "a" (fifo)) 324 325#define MAC_ESP_PIO_FILL(operands, reg1) \ 326 asm volatile ( \ 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 " moveb " operands " \n" \ 340 " moveb " operands " \n" \ 341 " moveb " operands " \n" \ 342 " moveb " operands " \n" \ 343 " subqw #8,%1 \n" \ 344 " subqw #8,%1 \n" \ 345 : "+a" (addr), "+r" (reg1) \ 346 : "a" (fifo)) 347 348#define MAC_ESP_FIFO_SIZE 16 349 350static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, 351 u32 dma_count, int write, u8 cmd) 352{ 353 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); 354 u8 *fifo = esp->regs + ESP_FDATA * 16; 355 356 disable_irq(esp->host->irq); 357 358 cmd &= ~ESP_CMD_DMA; 359 mep->error = 0; 360 361 if (write) { 362 scsi_esp_cmd(esp, cmd); 363 364 while (1) { 365 unsigned int n; 366 367 n = mac_esp_wait_for_fifo(esp); 368 if (!n) 369 break; 370 371 if (n > esp_count) 372 n = esp_count; 373 esp_count -= n; 374 375 MAC_ESP_PIO_LOOP("%2@,%0@+", n); 376 377 if (!esp_count) 378 break; 379 380 if (mac_esp_wait_for_intr(esp)) 381 break; 382 383 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) && 384 ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP)) 385 break; 386 387 esp->ireg = esp_read8(ESP_INTRPT); 388 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) != 389 ESP_INTR_BSERV) 390 break; 391 392 scsi_esp_cmd(esp, ESP_CMD_TI); 393 } 394 } else { 395 scsi_esp_cmd(esp, ESP_CMD_FLUSH); 396 397 if (esp_count >= MAC_ESP_FIFO_SIZE) 398 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 399 else 400 MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count); 401 402 scsi_esp_cmd(esp, cmd); 403 404 while (esp_count) { 405 unsigned int n; 406 407 if (mac_esp_wait_for_intr(esp)) 408 break; 409 410 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) && 411 ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP)) 412 break; 413 414 esp->ireg = esp_read8(ESP_INTRPT); 415 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) != 416 ESP_INTR_BSERV) 417 break; 418 419 n = MAC_ESP_FIFO_SIZE - 420 (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES); 421 if (n > esp_count) 422 n = esp_count; 423 424 if (n == MAC_ESP_FIFO_SIZE) { 425 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count); 426 } else { 427 esp_count -= n; 428 MAC_ESP_PIO_LOOP("%0@+,%2@", n); 429 } 430 431 scsi_esp_cmd(esp, ESP_CMD_TI); 432 } 433 } 434 435 enable_irq(esp->host->irq); 436} 437 438static int mac_esp_irq_pending(struct esp *esp) 439{ 440 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) 441 return 1; 442 return 0; 443} 444 445static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len) 446{ 447 return dma_len > 0xFFFF ? 0xFFFF : dma_len; 448} 449 450static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id) 451{ 452 int got_intr; 453 454 /* 455 * This is an edge triggered IRQ, so we have to be careful to 456 * avoid missing a transition when it is shared by two ESP devices. 457 */ 458 459 do { 460 got_intr = 0; 461 if (esp_chips[0] && 462 (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) { 463 (void)scsi_esp_intr(irq, esp_chips[0]); 464 got_intr = 1; 465 } 466 if (esp_chips[1] && 467 (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) { 468 (void)scsi_esp_intr(irq, esp_chips[1]); 469 got_intr = 1; 470 } 471 } while (got_intr); 472 473 return IRQ_HANDLED; 474} 475 476static struct esp_driver_ops mac_esp_ops = { 477 .esp_write8 = mac_esp_write8, 478 .esp_read8 = mac_esp_read8, 479 .map_single = mac_esp_map_single, 480 .map_sg = mac_esp_map_sg, 481 .unmap_single = mac_esp_unmap_single, 482 .unmap_sg = mac_esp_unmap_sg, 483 .irq_pending = mac_esp_irq_pending, 484 .dma_length_limit = mac_esp_dma_length_limit, 485 .reset_dma = mac_esp_reset_dma, 486 .dma_drain = mac_esp_dma_drain, 487 .dma_invalidate = mac_esp_dma_invalidate, 488 .send_dma_cmd = mac_esp_send_pdma_cmd, 489 .dma_error = mac_esp_dma_error, 490}; 491 492static int __devinit esp_mac_probe(struct platform_device *dev) 493{ 494 struct scsi_host_template *tpnt = &scsi_esp_template; 495 struct Scsi_Host *host; 496 struct esp *esp; 497 int err; 498 struct mac_esp_priv *mep; 499 500 if (!MACH_IS_MAC) 501 return -ENODEV; 502 503 if (dev->id > 1) 504 return -ENODEV; 505 506 host = scsi_host_alloc(tpnt, sizeof(struct esp)); 507 508 err = -ENOMEM; 509 if (!host) 510 goto fail; 511 512 host->max_id = 8; 513 host->use_clustering = DISABLE_CLUSTERING; 514 esp = shost_priv(host); 515 516 esp->host = host; 517 esp->dev = dev; 518 519 esp->command_block = kzalloc(16, GFP_KERNEL); 520 if (!esp->command_block) 521 goto fail_unlink; 522 esp->command_block_dma = (dma_addr_t)esp->command_block; 523 524 esp->scsi_id = 7; 525 host->this_id = esp->scsi_id; 526 esp->scsi_id_mask = 1 << esp->scsi_id; 527 528 mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL); 529 if (!mep) 530 goto fail_free_command_block; 531 mep->esp = esp; 532 platform_set_drvdata(dev, mep); 533 534 switch (macintosh_config->scsi_type) { 535 case MAC_SCSI_QUADRA: 536 esp->cfreq = 16500000; 537 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA; 538 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 539 mep->pdma_regs = NULL; 540 break; 541 case MAC_SCSI_QUADRA2: 542 esp->cfreq = 25000000; 543 esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 + 544 dev->id * MAC_ESP_REGS_SPACING); 545 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; 546 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG + 547 dev->id * MAC_ESP_PDMA_REG_SPACING); 548 nubus_writel(0x1d1, mep->pdma_regs); 549 break; 550 case MAC_SCSI_QUADRA3: 551 /* These quadras have a real DMA controller (the PSC) but we 552 * don't know how to drive it so we must use PIO instead. 553 */ 554 esp->cfreq = 25000000; 555 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3; 556 mep->pdma_io = NULL; 557 mep->pdma_regs = NULL; 558 break; 559 } 560 561 esp->ops = &mac_esp_ops; 562 if (mep->pdma_io == NULL) { 563 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id); 564 esp_write8(0, ESP_TCLOW); 565 esp_write8(0, ESP_TCMED); 566 esp->flags = ESP_FLAG_DISABLE_SYNC; 567 mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd; 568 } else { 569 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id); 570 } 571 572 host->irq = IRQ_MAC_SCSI; 573 esp_chips[dev->id] = esp; 574 mb(); 575 if (esp_chips[!dev->id] == NULL) { 576 err = request_irq(host->irq, mac_scsi_esp_intr, 0, 577 "Mac ESP", NULL); 578 if (err < 0) { 579 esp_chips[dev->id] = NULL; 580 goto fail_free_priv; 581 } 582 } 583 584 err = scsi_esp_register(esp, &dev->dev); 585 if (err) 586 goto fail_free_irq; 587 588 return 0; 589 590fail_free_irq: 591 if (esp_chips[!dev->id] == NULL) 592 free_irq(host->irq, esp); 593fail_free_priv: 594 kfree(mep); 595fail_free_command_block: 596 kfree(esp->command_block); 597fail_unlink: 598 scsi_host_put(host); 599fail: 600 return err; 601} 602 603static int __devexit esp_mac_remove(struct platform_device *dev) 604{ 605 struct mac_esp_priv *mep = platform_get_drvdata(dev); 606 struct esp *esp = mep->esp; 607 unsigned int irq = esp->host->irq; 608 609 scsi_esp_unregister(esp); 610 611 esp_chips[dev->id] = NULL; 612 if (!(esp_chips[0] || esp_chips[1])) 613 free_irq(irq, NULL); 614 615 kfree(mep); 616 617 kfree(esp->command_block); 618 619 scsi_host_put(esp->host); 620 621 return 0; 622} 623 624static struct platform_driver esp_mac_driver = { 625 .probe = esp_mac_probe, 626 .remove = __devexit_p(esp_mac_remove), 627 .driver = { 628 .name = DRV_MODULE_NAME, 629 .owner = THIS_MODULE, 630 }, 631}; 632 633static int __init mac_esp_init(void) 634{ 635 return platform_driver_register(&esp_mac_driver); 636} 637 638static void __exit mac_esp_exit(void) 639{ 640 platform_driver_unregister(&esp_mac_driver); 641} 642 643MODULE_DESCRIPTION("Mac ESP SCSI driver"); 644MODULE_AUTHOR("Finn Thain <fthain@telegraphics.com.au>"); 645MODULE_LICENSE("GPL v2"); 646MODULE_VERSION(DRV_VERSION); 647MODULE_ALIAS("platform:" DRV_MODULE_NAME); 648 649module_init(mac_esp_init); 650module_exit(mac_esp_exit); 651