drivers/scsi/mac_scsi.c

   1 /*
   2  * Generic Macintosh NCR5380 driver
   3  *
   4  * Copyright 1998, Michael Schmitz <mschmitz@lbl.gov>
   5  *
   6  * Copyright 2019 Finn Thain
   7  *
   8  * derived in part from:
   9  */
  10 /*
  11  * Generic Generic NCR5380 driver
  12  *
  13  * Copyright 1995, Russell King
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/types.h>
  18 #include <linux/module.h>
  19 #include <linux/ioport.h>
  20 #include <linux/init.h>
  21 #include <linux/blkdev.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/platform_device.h>
  24
  25 #include <asm/hwtest.h>
  26 #include <asm/io.h>
  27 #include <asm/macints.h>
  28 #include <asm/setup.h>
  29
  30 #include <scsi/scsi_host.h>
  31
  32 /* Definitions for the core NCR5380 driver. */
  33
  34 #define NCR5380_implementation_fields   int pdma_residual
  35
  36 #define NCR5380_read(reg)           in_8(hostdata->io + ((reg) << 4))
  37 #define NCR5380_write(reg, value)   out_8(hostdata->io + ((reg) << 4), value)
  38
  39 #define NCR5380_dma_xfer_len            macscsi_dma_xfer_len
  40 #define NCR5380_dma_recv_setup          macscsi_pread
  41 #define NCR5380_dma_send_setup          macscsi_pwrite
  42 #define NCR5380_dma_residual            macscsi_dma_residual
  43
  44 #define NCR5380_intr                    macscsi_intr
  45 #define NCR5380_queue_command           macscsi_queue_command
  46 #define NCR5380_abort                   macscsi_abort
  47 #define NCR5380_host_reset              macscsi_host_reset
  48 #define NCR5380_info                    macscsi_info
  49
  50 #include "NCR5380.h"
  51
  52 static int setup_can_queue = -1;
  53 module_param(setup_can_queue, int, 0);
  54 static int setup_cmd_per_lun = -1;
  55 module_param(setup_cmd_per_lun, int, 0);
  56 static int setup_sg_tablesize = -1;
  57 module_param(setup_sg_tablesize, int, 0);
  58 static int setup_use_pdma = 512;
  59 module_param(setup_use_pdma, int, 0);
  60 static int setup_hostid = -1;
  61 module_param(setup_hostid, int, 0);
  62 static int setup_toshiba_delay = -1;
  63 module_param(setup_toshiba_delay, int, 0);
  64
  65 #ifndef MODULE
  66 static int __init mac_scsi_setup(char *str)
  67 {
  68         int ints[8];
  69
  70         (void)get_options(str, ARRAY_SIZE(ints), ints);
  71
  72         if (ints[0] < 1) {
  73                 pr_err("Usage: mac5380=<can_queue>[,<cmd_per_lun>[,<sg_tablesize>[,<hostid>[,<use_tags>[,<use_pdma>[,<toshiba_delay>]]]]]]\n");
  74                 return 0;
  75         }
  76         if (ints[0] >= 1)
  77                 setup_can_queue = ints[1];
  78         if (ints[0] >= 2)
  79                 setup_cmd_per_lun = ints[2];
  80         if (ints[0] >= 3)
  81                 setup_sg_tablesize = ints[3];
  82         if (ints[0] >= 4)
  83                 setup_hostid = ints[4];
  84         /* ints[5] (use_tagged_queuing) is ignored */
  85         if (ints[0] >= 6)
  86                 setup_use_pdma = ints[6];
  87         if (ints[0] >= 7)
  88                 setup_toshiba_delay = ints[7];
  89         return 1;
  90 }
  91
  92 __setup("mac5380=", mac_scsi_setup);
  93 #endif /* !MODULE */
  94
  95 /*
  96  * According to "Inside Macintosh: Devices", Mac OS requires disk drivers to
  97  * specify the number of bytes between the delays expected from a SCSI target.
  98  * This allows the operating system to "prevent bus errors when a target fails
  99  * to deliver the next byte within the processor bus error timeout period."
 100  * Linux SCSI drivers lack knowledge of the timing behaviour of SCSI targets
 101  * so bus errors are unavoidable.
 102  *
 103  * If a MOVE.B instruction faults, we assume that zero bytes were transferred
 104  * and simply retry. That assumption probably depends on target behaviour but
 105  * seems to hold up okay. The NOP provides synchronization: without it the
 106  * fault can sometimes occur after the program counter has moved past the
 107  * offending instruction. Post-increment addressing can't be used.
 108  */
 109
 110 #define MOVE_BYTE(operands) \
 111         asm volatile ( \
 112                 "1:     moveb " operands "     \n" \
 113                 "11:    nop                    \n" \
 114                 "       addq #1,%0             \n" \
 115                 "       subq #1,%1             \n" \
 116                 "40:                           \n" \
 117                 "                              \n" \
 118                 ".section .fixup,\"ax\"        \n" \
 119                 ".even                         \n" \
 120                 "90:    movel #1, %2           \n" \
 121                 "       jra 40b                \n" \
 122                 ".previous                     \n" \
 123                 "                              \n" \
 124                 ".section __ex_table,\"a\"     \n" \
 125                 ".align  4                     \n" \
 126                 ".long   1b,90b                \n" \
 127                 ".long  11b,90b                \n" \
 128                 ".previous                     \n" \
 129                 : "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
 130
 131 /*
 132  * If a MOVE.W (or MOVE.L) instruction faults, it cannot be retried because
 133  * the residual byte count would be uncertain. In that situation the MOVE_WORD
 134  * macro clears n in the fixup section to abort the transfer.
 135  */
 136
 137 #define MOVE_WORD(operands) \
 138         asm volatile ( \
 139                 "1:     movew " operands "     \n" \
 140                 "11:    nop                    \n" \
 141                 "       subq #2,%1             \n" \
 142                 "40:                           \n" \
 143                 "                              \n" \
 144                 ".section .fixup,\"ax\"        \n" \
 145                 ".even                         \n" \
 146                 "90:    movel #0, %1           \n" \
 147                 "       movel #2, %2           \n" \
 148                 "       jra 40b                \n" \
 149                 ".previous                     \n" \
 150                 "                              \n" \
 151                 ".section __ex_table,\"a\"     \n" \
 152                 ".align  4                     \n" \
 153                 ".long   1b,90b                \n" \
 154                 ".long  11b,90b                \n" \
 155                 ".previous                     \n" \
 156                 : "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
 157
 158 #define MOVE_16_WORDS(operands) \
 159         asm volatile ( \
 160                 "1:     movew " operands "     \n" \
 161                 "2:     movew " operands "     \n" \
 162                 "3:     movew " operands "     \n" \
 163                 "4:     movew " operands "     \n" \
 164                 "5:     movew " operands "     \n" \
 165                 "6:     movew " operands "     \n" \
 166                 "7:     movew " operands "     \n" \
 167                 "8:     movew " operands "     \n" \
 168                 "9:     movew " operands "     \n" \
 169                 "10:    movew " operands "     \n" \
 170                 "11:    movew " operands "     \n" \
 171                 "12:    movew " operands "     \n" \
 172                 "13:    movew " operands "     \n" \
 173                 "14:    movew " operands "     \n" \
 174                 "15:    movew " operands "     \n" \
 175                 "16:    movew " operands "     \n" \
 176                 "17:    nop                    \n" \
 177                 "       subl  #32,%1           \n" \
 178                 "40:                           \n" \
 179                 "                              \n" \
 180                 ".section .fixup,\"ax\"        \n" \
 181                 ".even                         \n" \
 182                 "90:    movel #0, %1           \n" \
 183                 "       movel #2, %2           \n" \
 184                 "       jra 40b                \n" \
 185                 ".previous                     \n" \
 186                 "                              \n" \
 187                 ".section __ex_table,\"a\"     \n" \
 188                 ".align  4                     \n" \
 189                 ".long   1b,90b                \n" \
 190                 ".long   2b,90b                \n" \
 191                 ".long   3b,90b                \n" \
 192                 ".long   4b,90b                \n" \
 193                 ".long   5b,90b                \n" \
 194                 ".long   6b,90b                \n" \
 195                 ".long   7b,90b                \n" \
 196                 ".long   8b,90b                \n" \
 197                 ".long   9b,90b                \n" \
 198                 ".long  10b,90b                \n" \
 199                 ".long  11b,90b                \n" \
 200                 ".long  12b,90b                \n" \
 201                 ".long  13b,90b                \n" \
 202                 ".long  14b,90b                \n" \
 203                 ".long  15b,90b                \n" \
 204                 ".long  16b,90b                \n" \
 205                 ".long  17b,90b                \n" \
 206                 ".previous                     \n" \
 207                 : "+a" (addr), "+r" (n), "+r" (result) : "a" (io))
 208
 209 #define MAC_PDMA_DELAY          32
 210
 211 static inline int mac_pdma_recv(void __iomem *io, unsigned char *start, int n)
 212 {
 213         unsigned char *addr = start;
 214         int result = 0;
 215
 216         if (n >= 1) {
 217                 MOVE_BYTE("%3@,%0@");
 218                 if (result)
 219                         goto out;
 220         }
 221         if (n >= 1 && ((unsigned long)addr & 1)) {
 222                 MOVE_BYTE("%3@,%0@");
 223                 if (result)
 224                         goto out;
 225         }
 226         while (n >= 32)
 227                 MOVE_16_WORDS("%3@,%0@+");
 228         while (n >= 2)
 229                 MOVE_WORD("%3@,%0@+");
 230         if (result)
 231                 return start - addr; /* Negated to indicate uncertain length */
 232         if (n == 1)
 233                 MOVE_BYTE("%3@,%0@");
 234 out:
 235         return addr - start;
 236 }
 237
 238 static inline int mac_pdma_send(unsigned char *start, void __iomem *io, int n)
 239 {
 240         unsigned char *addr = start;
 241         int result = 0;
 242
 243         if (n >= 1) {
 244                 MOVE_BYTE("%0@,%3@");
 245                 if (result)
 246                         goto out;
 247         }
 248         if (n >= 1 && ((unsigned long)addr & 1)) {
 249                 MOVE_BYTE("%0@,%3@");
 250                 if (result)
 251                         goto out;
 252         }
 253         while (n >= 32)
 254                 MOVE_16_WORDS("%0@+,%3@");
 255         while (n >= 2)
 256                 MOVE_WORD("%0@+,%3@");
 257         if (result)
 258                 return start - addr; /* Negated to indicate uncertain length */
 259         if (n == 1)
 260                 MOVE_BYTE("%0@,%3@");
 261 out:
 262         return addr - start;
 263 }
 264
 265 static inline int macscsi_pread(struct NCR5380_hostdata *hostdata,
 266                                 unsigned char *dst, int len)
 267 {
 268         u8 __iomem *s = hostdata->pdma_io + (INPUT_DATA_REG << 4);
 269         unsigned char *d = dst;
 270
 271         hostdata->pdma_residual = len;
 272
 273         while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
 274                                       BASR_DRQ | BASR_PHASE_MATCH,
 275                                       BASR_DRQ | BASR_PHASE_MATCH, HZ / 64)) {
 276                 int bytes;
 277
 278                 bytes = mac_pdma_recv(s, d, min(hostdata->pdma_residual, 512));
 279
 280                 if (bytes > 0) {
 281                         d += bytes;
 282                         hostdata->pdma_residual -= bytes;
 283                 }
 284
 285                 if (hostdata->pdma_residual == 0)
 286                         return 0;
 287
 288                 if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
 289                                            BUS_AND_STATUS_REG, BASR_ACK,
 290                                            BASR_ACK, HZ / 64) < 0)
 291                         scmd_printk(KERN_DEBUG, hostdata->connected,
 292                                     "%s: !REQ and !ACK\n", __func__);
 293                 if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
 294                         return 0;
 295
 296                 if (bytes == 0)
 297                         udelay(MAC_PDMA_DELAY);
 298
 299                 if (bytes >= 0)
 300                         continue;
 301
 302                 dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
 303                          "%s: bus error (%d/%d)\n", __func__, d - dst, len);
 304                 NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
 305                 return -1;
 306         }
 307
 308         scmd_printk(KERN_ERR, hostdata->connected,
 309                     "%s: phase mismatch or !DRQ\n", __func__);
 310         NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
 311         return -1;
 312 }
 313
 314 static inline int macscsi_pwrite(struct NCR5380_hostdata *hostdata,
 315                                  unsigned char *src, int len)
 316 {
 317         unsigned char *s = src;
 318         u8 __iomem *d = hostdata->pdma_io + (OUTPUT_DATA_REG << 4);
 319
 320         hostdata->pdma_residual = len;
 321
 322         while (!NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
 323                                       BASR_DRQ | BASR_PHASE_MATCH,
 324                                       BASR_DRQ | BASR_PHASE_MATCH, HZ / 64)) {
 325                 int bytes;
 326
 327                 bytes = mac_pdma_send(s, d, min(hostdata->pdma_residual, 512));
 328
 329                 if (bytes > 0) {
 330                         s += bytes;
 331                         hostdata->pdma_residual -= bytes;
 332                 }
 333
 334                 if (hostdata->pdma_residual == 0) {
 335                         if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
 336                                                   TCR_LAST_BYTE_SENT,
 337                                                   TCR_LAST_BYTE_SENT, HZ / 64) < 0)
 338                                 scmd_printk(KERN_ERR, hostdata->connected,
 339                                             "%s: Last Byte Sent timeout\n", __func__);
 340                         return 0;
 341                 }
 342
 343                 if (NCR5380_poll_politely2(hostdata, STATUS_REG, SR_REQ, SR_REQ,
 344                                            BUS_AND_STATUS_REG, BASR_ACK,
 345                                            BASR_ACK, HZ / 64) < 0)
 346                         scmd_printk(KERN_DEBUG, hostdata->connected,
 347                                     "%s: !REQ and !ACK\n", __func__);
 348                 if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))
 349                         return 0;
 350
 351                 if (bytes == 0)
 352                         udelay(MAC_PDMA_DELAY);
 353
 354                 if (bytes >= 0)
 355                         continue;
 356
 357                 dsprintk(NDEBUG_PSEUDO_DMA, hostdata->host,
 358                          "%s: bus error (%d/%d)\n", __func__, s - src, len);
 359                 NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
 360                 return -1;
 361         }
 362
 363         scmd_printk(KERN_ERR, hostdata->connected,
 364                     "%s: phase mismatch or !DRQ\n", __func__);
 365         NCR5380_dprint(NDEBUG_PSEUDO_DMA, hostdata->host);
 366         return -1;
 367 }
 368
 369 static int macscsi_dma_xfer_len(struct NCR5380_hostdata *hostdata,
 370                                 struct scsi_cmnd *cmd)
 371 {
 372         if (hostdata->flags & FLAG_NO_PSEUDO_DMA ||
 373             cmd->SCp.this_residual < setup_use_pdma)
 374                 return 0;
 375
 376         return cmd->SCp.this_residual;
 377 }
 378
 379 static int macscsi_dma_residual(struct NCR5380_hostdata *hostdata)
 380 {
 381         return hostdata->pdma_residual;
 382 }
 383
 384 #include "NCR5380.c"
 385
 386 #define DRV_MODULE_NAME         "mac_scsi"
 387 #define PFX                     DRV_MODULE_NAME ": "
 388
 389 static struct scsi_host_template mac_scsi_template = {
 390         .module                 = THIS_MODULE,
 391         .proc_name              = DRV_MODULE_NAME,
 392         .name                   = "Macintosh NCR5380 SCSI",
 393         .info                   = macscsi_info,
 394         .queuecommand           = macscsi_queue_command,
 395         .eh_abort_handler       = macscsi_abort,
 396         .eh_host_reset_handler  = macscsi_host_reset,
 397         .can_queue              = 16,
 398         .this_id                = 7,
 399         .sg_tablesize           = 1,
 400         .cmd_per_lun            = 2,
 401         .use_clustering         = DISABLE_CLUSTERING,
 402         .cmd_size               = NCR5380_CMD_SIZE,
 403         .max_sectors            = 128,
 404 };
 405
 406 static int __init mac_scsi_probe(struct platform_device *pdev)
 407 {
 408         struct Scsi_Host *instance;
 409         struct NCR5380_hostdata *hostdata;
 410         int error;
 411         int host_flags = 0;
 412         struct resource *irq, *pio_mem, *pdma_mem = NULL;
 413
 414         pio_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 415         if (!pio_mem)
 416                 return -ENODEV;
 417
 418         pdma_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 419
 420         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 421
 422         if (!hwreg_present((unsigned char *)pio_mem->start +
 423                            (STATUS_REG << 4))) {
 424                 pr_info(PFX "no device detected at %pap\n", &pio_mem->start);
 425                 return -ENODEV;
 426         }
 427
 428         if (setup_can_queue > 0)
 429                 mac_scsi_template.can_queue = setup_can_queue;
 430         if (setup_cmd_per_lun > 0)
 431                 mac_scsi_template.cmd_per_lun = setup_cmd_per_lun;
 432         if (setup_sg_tablesize > 0)
 433                 mac_scsi_template.sg_tablesize = setup_sg_tablesize;
 434         if (setup_hostid >= 0)
 435                 mac_scsi_template.this_id = setup_hostid & 7;
 436
 437         instance = scsi_host_alloc(&mac_scsi_template,
 438                                    sizeof(struct NCR5380_hostdata));
 439         if (!instance)
 440                 return -ENOMEM;
 441
 442         if (irq)
 443                 instance->irq = irq->start;
 444         else
 445                 instance->irq = NO_IRQ;
 446
 447         hostdata = shost_priv(instance);
 448         hostdata->base = pio_mem->start;
 449         hostdata->io = (u8 __iomem *)pio_mem->start;
 450
 451         if (pdma_mem && setup_use_pdma)
 452                 hostdata->pdma_io = (u8 __iomem *)pdma_mem->start;
 453         else
 454                 host_flags |= FLAG_NO_PSEUDO_DMA;
 455
 456         host_flags |= setup_toshiba_delay > 0 ? FLAG_TOSHIBA_DELAY : 0;
 457
 458         error = NCR5380_init(instance, host_flags | FLAG_LATE_DMA_SETUP);
 459         if (error)
 460                 goto fail_init;
 461
 462         if (instance->irq != NO_IRQ) {
 463                 error = request_irq(instance->irq, macscsi_intr, IRQF_SHARED,
 464                                     "NCR5380", instance);
 465                 if (error)
 466                         goto fail_irq;
 467         }
 468
 469         NCR5380_maybe_reset_bus(instance);
 470
 471         error = scsi_add_host(instance, NULL);
 472         if (error)
 473                 goto fail_host;
 474
 475         platform_set_drvdata(pdev, instance);
 476
 477         scsi_scan_host(instance);
 478         return 0;
 479
 480 fail_host:
 481         if (instance->irq != NO_IRQ)
 482                 free_irq(instance->irq, instance);
 483 fail_irq:
 484         NCR5380_exit(instance);
 485 fail_init:
 486         scsi_host_put(instance);
 487         return error;
 488 }
 489
 490 static int __exit mac_scsi_remove(struct platform_device *pdev)
 491 {
 492         struct Scsi_Host *instance = platform_get_drvdata(pdev);
 493
 494         scsi_remove_host(instance);
 495         if (instance->irq != NO_IRQ)
 496                 free_irq(instance->irq, instance);
 497         NCR5380_exit(instance);
 498         scsi_host_put(instance);
 499         return 0;
 500 }
 501
 502 static struct platform_driver mac_scsi_driver = {
 503         .remove = __exit_p(mac_scsi_remove),
 504         .driver = {
 505                 .name   = DRV_MODULE_NAME,
 506         },
 507 };
 508
 509 module_platform_driver_probe(mac_scsi_driver, mac_scsi_probe);
 510
 511 MODULE_ALIAS("platform:" DRV_MODULE_NAME);
 512 MODULE_LICENSE("GPL");