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Linux 2.6.17.7
[linux/fpc-iii.git] / drivers / scsi / mac53c94.c
blob93edaa8696cf35e0b54a72dc3cfd266931e2c18b
1 /*
2 * SCSI low-level driver for the 53c94 SCSI bus adaptor found
3 * on Power Macintosh computers, controlling the external SCSI chain.
4 * We assume the 53c94 is connected to a DBDMA (descriptor-based DMA)
5 * controller.
6 *
7 * Paul Mackerras, August 1996.
8 * Copyright (C) 1996 Paul Mackerras.
9 */
10 #include <linux/kernel.h>
11 #include <linux/delay.h>
12 #include <linux/types.h>
13 #include <linux/string.h>
14 #include <linux/slab.h>
15 #include <linux/blkdev.h>
16 #include <linux/proc_fs.h>
17 #include <linux/stat.h>
18 #include <linux/spinlock.h>
19 #include <linux/interrupt.h>
20 #include <asm/dbdma.h>
21 #include <asm/io.h>
22 #include <asm/pgtable.h>
23 #include <asm/prom.h>
24 #include <asm/system.h>
25 #include <asm/pci-bridge.h>
26 #include <asm/macio.h>
27
28 #include <scsi/scsi.h>
29 #include <scsi/scsi_cmnd.h>
30 #include <scsi/scsi_device.h>
31 #include <scsi/scsi_host.h>
32
33 #include "mac53c94.h"
34
35 enum fsc_phase {
36 idle,
37 selecting,
38 dataing,
39 completing,
40 busfreeing,
41 };
42
43 struct fsc_state {
44 struct mac53c94_regs __iomem *regs;
45 int intr;
46 struct dbdma_regs __iomem *dma;
47 int dmaintr;
48 int clk_freq;
49 struct Scsi_Host *host;
50 struct scsi_cmnd *request_q;
51 struct scsi_cmnd *request_qtail;
52 struct scsi_cmnd *current_req; /* req we're currently working on */
53 enum fsc_phase phase; /* what we're currently trying to do */
54 struct dbdma_cmd *dma_cmds; /* space for dbdma commands, aligned */
55 void *dma_cmd_space;
56 struct pci_dev *pdev;
57 dma_addr_t dma_addr;
58 struct macio_dev *mdev;
59 };
60
61 static void mac53c94_init(struct fsc_state *);
62 static void mac53c94_start(struct fsc_state *);
63 static void mac53c94_interrupt(int, void *, struct pt_regs *);
64 static irqreturn_t do_mac53c94_interrupt(int, void *, struct pt_regs *);
65 static void cmd_done(struct fsc_state *, int result);
66 static void set_dma_cmds(struct fsc_state *, struct scsi_cmnd *);
67
68
69 static int mac53c94_queue(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
70 {
71 struct fsc_state *state;
72
73 #if 0
74 if (cmd->sc_data_direction == DMA_TO_DEVICE) {
75 int i;
76 printk(KERN_DEBUG "mac53c94_queue %p: command is", cmd);
77 for (i = 0; i < cmd->cmd_len; ++i)
78 printk(" %.2x", cmd->cmnd[i]);
79 printk("\n" KERN_DEBUG "use_sg=%d request_bufflen=%d request_buffer=%p\n",
80 cmd->use_sg, cmd->request_bufflen, cmd->request_buffer);
81 }
82 #endif
83
84 cmd->scsi_done = done;
85 cmd->host_scribble = NULL;
86
87 state = (struct fsc_state *) cmd->device->host->hostdata;
88
89 if (state->request_q == NULL)
90 state->request_q = cmd;
91 else
92 state->request_qtail->host_scribble = (void *) cmd;
93 state->request_qtail = cmd;
94
95 if (state->phase == idle)
96 mac53c94_start(state);
97
98 return 0;
99 }
100
101 static int mac53c94_host_reset(struct scsi_cmnd *cmd)
102 {
103 struct fsc_state *state = (struct fsc_state *) cmd->device->host->hostdata;
104 struct mac53c94_regs __iomem *regs = state->regs;
105 struct dbdma_regs __iomem *dma = state->dma;
106 unsigned long flags;
107
108 spin_lock_irqsave(cmd->device->host->host_lock, flags);
109
110 writel((RUN|PAUSE|FLUSH|WAKE) << 16, &dma->control);
111 writeb(CMD_SCSI_RESET, &regs->command); /* assert RST */
112 udelay(100); /* leave it on for a while (>= 25us) */
113 writeb(CMD_RESET, &regs->command);
114 udelay(20);
115 mac53c94_init(state);
116 writeb(CMD_NOP, &regs->command);
117
118 spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
119 return SUCCESS;
120 }
121
122 static void mac53c94_init(struct fsc_state *state)
123 {
124 struct mac53c94_regs __iomem *regs = state->regs;
125 struct dbdma_regs __iomem *dma = state->dma;
126 int x;
127
128 writeb(state->host->this_id | CF1_PAR_ENABLE, &regs->config1);
129 writeb(TIMO_VAL(250), &regs->sel_timeout); /* 250ms */
130 writeb(CLKF_VAL(state->clk_freq), &regs->clk_factor);
131 writeb(CF2_FEATURE_EN, &regs->config2);
132 writeb(0, &regs->config3);
133 writeb(0, &regs->sync_period);
134 writeb(0, &regs->sync_offset);
135 x = readb(&regs->interrupt);
136 writel((RUN|PAUSE|FLUSH|WAKE) << 16, &dma->control);
137 }
138
139 /*
140 * Start the next command for a 53C94.
141 * Should be called with interrupts disabled.
142 */
143 static void mac53c94_start(struct fsc_state *state)
144 {
145 struct scsi_cmnd *cmd;
146 struct mac53c94_regs __iomem *regs = state->regs;
147 int i;
148
149 if (state->phase != idle || state->current_req != NULL)
150 panic("inappropriate mac53c94_start (state=%p)", state);
151 if (state->request_q == NULL)
152 return;
153 state->current_req = cmd = state->request_q;
154 state->request_q = (struct scsi_cmnd *) cmd->host_scribble;
155
156 /* Off we go */
157 writeb(0, &regs->count_lo);
158 writeb(0, &regs->count_mid);
159 writeb(0, &regs->count_hi);
160 writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
161 udelay(1);
162 writeb(CMD_FLUSH, &regs->command);
163 udelay(1);
164 writeb(cmd->device->id, &regs->dest_id);
165 writeb(0, &regs->sync_period);
166 writeb(0, &regs->sync_offset);
167
168 /* load the command into the FIFO */
169 for (i = 0; i < cmd->cmd_len; ++i)
170 writeb(cmd->cmnd[i], &regs->fifo);
171
172 /* do select without ATN XXX */
173 writeb(CMD_SELECT, &regs->command);
174 state->phase = selecting;
175
176 if (cmd->use_sg > 0 || cmd->request_bufflen != 0)
177 set_dma_cmds(state, cmd);
178 }
179
180 static irqreturn_t do_mac53c94_interrupt(int irq, void *dev_id, struct pt_regs *ptregs)
181 {
182 unsigned long flags;
183 struct Scsi_Host *dev = ((struct fsc_state *) dev_id)->current_req->device->host;
184
185 spin_lock_irqsave(dev->host_lock, flags);
186 mac53c94_interrupt(irq, dev_id, ptregs);
187 spin_unlock_irqrestore(dev->host_lock, flags);
188 return IRQ_HANDLED;
189 }
190
191 static void mac53c94_interrupt(int irq, void *dev_id, struct pt_regs *ptregs)
192 {
193 struct fsc_state *state = (struct fsc_state *) dev_id;
194 struct mac53c94_regs __iomem *regs = state->regs;
195 struct dbdma_regs __iomem *dma = state->dma;
196 struct scsi_cmnd *cmd = state->current_req;
197 int nb, stat, seq, intr;
198 static int mac53c94_errors;
199
200 /*
201 * Apparently, reading the interrupt register unlatches
202 * the status and sequence step registers.
203 */
204 seq = readb(&regs->seqstep);
205 stat = readb(&regs->status);
206 intr = readb(&regs->interrupt);
207
208 #if 0
209 printk(KERN_DEBUG "mac53c94_intr, intr=%x stat=%x seq=%x phase=%d\n",
210 intr, stat, seq, state->phase);
211 #endif
212
213 if (intr & INTR_RESET) {
214 /* SCSI bus was reset */
215 printk(KERN_INFO "external SCSI bus reset detected\n");
216 writeb(CMD_NOP, &regs->command);
217 writel(RUN << 16, &dma->control); /* stop dma */
218 cmd_done(state, DID_RESET << 16);
219 return;
220 }
221 if (intr & INTR_ILL_CMD) {
222 printk(KERN_ERR "53c94: invalid cmd, intr=%x stat=%x seq=%x phase=%d\n",
223 intr, stat, seq, state->phase);
224 cmd_done(state, DID_ERROR << 16);
225 return;
226 }
227 if (stat & STAT_ERROR) {
228 #if 0
229 /* XXX these seem to be harmless? */
230 printk("53c94: bad error, intr=%x stat=%x seq=%x phase=%d\n",
231 intr, stat, seq, state->phase);
232 #endif
233 ++mac53c94_errors;
234 writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
235 }
236 if (cmd == 0) {
237 printk(KERN_DEBUG "53c94: interrupt with no command active?\n");
238 return;
239 }
240 if (stat & STAT_PARITY) {
241 printk(KERN_ERR "mac53c94: parity error\n");
242 cmd_done(state, DID_PARITY << 16);
243 return;
244 }
245 switch (state->phase) {
246 case selecting:
247 if (intr & INTR_DISCONNECT) {
248 /* selection timed out */
249 cmd_done(state, DID_BAD_TARGET << 16);
250 return;
251 }
252 if (intr != INTR_BUS_SERV + INTR_DONE) {
253 printk(KERN_DEBUG "got intr %x during selection\n", intr);
254 cmd_done(state, DID_ERROR << 16);
255 return;
256 }
257 if ((seq & SS_MASK) != SS_DONE) {
258 printk(KERN_DEBUG "seq step %x after command\n", seq);
259 cmd_done(state, DID_ERROR << 16);
260 return;
261 }
262 writeb(CMD_NOP, &regs->command);
263 /* set DMA controller going if any data to transfer */
264 if ((stat & (STAT_MSG|STAT_CD)) == 0
265 && (cmd->use_sg > 0 || cmd->request_bufflen != 0)) {
266 nb = cmd->SCp.this_residual;
267 if (nb > 0xfff0)
268 nb = 0xfff0;
269 cmd->SCp.this_residual -= nb;
270 writeb(nb, &regs->count_lo);
271 writeb(nb >> 8, &regs->count_mid);
272 writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
273 writel(virt_to_phys(state->dma_cmds), &dma->cmdptr);
274 writel((RUN << 16) | RUN, &dma->control);
275 writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
276 state->phase = dataing;
277 break;
278 } else if ((stat & STAT_PHASE) == STAT_CD + STAT_IO) {
279 /* up to status phase already */
280 writeb(CMD_I_COMPLETE, &regs->command);
281 state->phase = completing;
282 } else {
283 printk(KERN_DEBUG "in unexpected phase %x after cmd\n",
284 stat & STAT_PHASE);
285 cmd_done(state, DID_ERROR << 16);
286 return;
287 }
288 break;
289
290 case dataing:
291 if (intr != INTR_BUS_SERV) {
292 printk(KERN_DEBUG "got intr %x before status\n", intr);
293 cmd_done(state, DID_ERROR << 16);
294 return;
295 }
296 if (cmd->SCp.this_residual != 0
297 && (stat & (STAT_MSG|STAT_CD)) == 0) {
298 /* Set up the count regs to transfer more */
299 nb = cmd->SCp.this_residual;
300 if (nb > 0xfff0)
301 nb = 0xfff0;
302 cmd->SCp.this_residual -= nb;
303 writeb(nb, &regs->count_lo);
304 writeb(nb >> 8, &regs->count_mid);
305 writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
306 writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
307 break;
308 }
309 if ((stat & STAT_PHASE) != STAT_CD + STAT_IO) {
310 printk(KERN_DEBUG "intr %x before data xfer complete\n", intr);
311 }
312 writel(RUN << 16, &dma->control); /* stop dma */
313 if (cmd->use_sg != 0) {
314 pci_unmap_sg(state->pdev,
315 (struct scatterlist *)cmd->request_buffer,
316 cmd->use_sg, cmd->sc_data_direction);
317 } else {
318 pci_unmap_single(state->pdev, state->dma_addr,
319 cmd->request_bufflen, cmd->sc_data_direction);
320 }
321 /* should check dma status */
322 writeb(CMD_I_COMPLETE, &regs->command);
323 state->phase = completing;
324 break;
325 case completing:
326 if (intr != INTR_DONE) {
327 printk(KERN_DEBUG "got intr %x on completion\n", intr);
328 cmd_done(state, DID_ERROR << 16);
329 return;
330 }
331 cmd->SCp.Status = readb(&regs->fifo);
332 cmd->SCp.Message = readb(&regs->fifo);
333 cmd->result = CMD_ACCEPT_MSG;
334 writeb(CMD_ACCEPT_MSG, &regs->command);
335 state->phase = busfreeing;
336 break;
337 case busfreeing:
338 if (intr != INTR_DISCONNECT) {
339 printk(KERN_DEBUG "got intr %x when expected disconnect\n", intr);
340 }
341 cmd_done(state, (DID_OK << 16) + (cmd->SCp.Message << 8)
342 + cmd->SCp.Status);
343 break;
344 default:
345 printk(KERN_DEBUG "don't know about phase %d\n", state->phase);
346 }
347 }
348
349 static void cmd_done(struct fsc_state *state, int result)
350 {
351 struct scsi_cmnd *cmd;
352
353 cmd = state->current_req;
354 if (cmd != 0) {
355 cmd->result = result;
356 (*cmd->scsi_done)(cmd);
357 state->current_req = NULL;
358 }
359 state->phase = idle;
360 mac53c94_start(state);
361 }
362
363 /*
364 * Set up DMA commands for transferring data.
365 */
366 static void set_dma_cmds(struct fsc_state *state, struct scsi_cmnd *cmd)
367 {
368 int i, dma_cmd, total;
369 struct scatterlist *scl;
370 struct dbdma_cmd *dcmds;
371 dma_addr_t dma_addr;
372 u32 dma_len;
373
374 dma_cmd = cmd->sc_data_direction == DMA_TO_DEVICE ?
375 OUTPUT_MORE : INPUT_MORE;
376 dcmds = state->dma_cmds;
377 if (cmd->use_sg > 0) {
378 int nseg;
379
380 total = 0;
381 scl = (struct scatterlist *) cmd->buffer;
382 nseg = pci_map_sg(state->pdev, scl, cmd->use_sg,
383 cmd->sc_data_direction);
384 for (i = 0; i < nseg; ++i) {
385 dma_addr = sg_dma_address(scl);
386 dma_len = sg_dma_len(scl);
387 if (dma_len > 0xffff)
388 panic("mac53c94: scatterlist element >= 64k");
389 total += dma_len;
390 st_le16(&dcmds->req_count, dma_len);
391 st_le16(&dcmds->command, dma_cmd);
392 st_le32(&dcmds->phy_addr, dma_addr);
393 dcmds->xfer_status = 0;
394 ++scl;
395 ++dcmds;
396 }
397 } else {
398 total = cmd->request_bufflen;
399 if (total > 0xffff)
400 panic("mac53c94: transfer size >= 64k");
401 dma_addr = pci_map_single(state->pdev, cmd->request_buffer,
402 total, cmd->sc_data_direction);
403 state->dma_addr = dma_addr;
404 st_le16(&dcmds->req_count, total);
405 st_le32(&dcmds->phy_addr, dma_addr);
406 dcmds->xfer_status = 0;
407 ++dcmds;
408 }
409 dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
410 st_le16(&dcmds[-1].command, dma_cmd);
411 st_le16(&dcmds->command, DBDMA_STOP);
412 cmd->SCp.this_residual = total;
413 }
414
415 static struct scsi_host_template mac53c94_template = {
416 .proc_name = "53c94",
417 .name = "53C94",
418 .queuecommand = mac53c94_queue,
419 .eh_host_reset_handler = mac53c94_host_reset,
420 .can_queue = 1,
421 .this_id = 7,
422 .sg_tablesize = SG_ALL,
423 .cmd_per_lun = 1,
424 .use_clustering = DISABLE_CLUSTERING,
425 };
426
427 static int mac53c94_probe(struct macio_dev *mdev, const struct of_device_id *match)
428 {
429 struct device_node *node = macio_get_of_node(mdev);
430 struct pci_dev *pdev = macio_get_pci_dev(mdev);
431 struct fsc_state *state;
432 struct Scsi_Host *host;
433 void *dma_cmd_space;
434 unsigned char *clkprop;
435 int proplen, rc = -ENODEV;
436
437 if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
438 printk(KERN_ERR "mac53c94: expected 2 addrs and intrs"
439 " (got %d/%d)\n",
440 macio_resource_count(mdev), macio_irq_count(mdev));
441 return -ENODEV;
442 }
443
444 if (macio_request_resources(mdev, "mac53c94") != 0) {
445 printk(KERN_ERR "mac53c94: unable to request memory resources");
446 return -EBUSY;
447 }
448
449 host = scsi_host_alloc(&mac53c94_template, sizeof(struct fsc_state));
450 if (host == NULL) {
451 printk(KERN_ERR "mac53c94: couldn't register host");
452 rc = -ENOMEM;
453 goto out_release;
454 }
455
456 state = (struct fsc_state *) host->hostdata;
457 macio_set_drvdata(mdev, state);
458 state->host = host;
459 state->pdev = pdev;
460 state->mdev = mdev;
461
462 state->regs = (struct mac53c94_regs __iomem *)
463 ioremap(macio_resource_start(mdev, 0), 0x1000);
464 state->intr = macio_irq(mdev, 0);
465 state->dma = (struct dbdma_regs __iomem *)
466 ioremap(macio_resource_start(mdev, 1), 0x1000);
467 state->dmaintr = macio_irq(mdev, 1);
468 if (state->regs == NULL || state->dma == NULL) {
469 printk(KERN_ERR "mac53c94: ioremap failed for %s\n",
470 node->full_name);
471 goto out_free;
472 }
473
474 clkprop = get_property(node, "clock-frequency", &proplen);
475 if (clkprop == NULL || proplen != sizeof(int)) {
476 printk(KERN_ERR "%s: can't get clock frequency, "
477 "assuming 25MHz\n", node->full_name);
478 state->clk_freq = 25000000;
479 } else
480 state->clk_freq = *(int *)clkprop;
481
482 /* Space for dma command list: +1 for stop command,
483 * +1 to allow for aligning.
484 * XXX FIXME: Use DMA consistent routines
485 */
486 dma_cmd_space = kmalloc((host->sg_tablesize + 2) *
487 sizeof(struct dbdma_cmd), GFP_KERNEL);
488 if (dma_cmd_space == 0) {
489 printk(KERN_ERR "mac53c94: couldn't allocate dma "
490 "command space for %s\n", node->full_name);
491 rc = -ENOMEM;
492 goto out_free;
493 }
494 state->dma_cmds = (struct dbdma_cmd *)DBDMA_ALIGN(dma_cmd_space);
495 memset(state->dma_cmds, 0, (host->sg_tablesize + 1)
496 * sizeof(struct dbdma_cmd));
497 state->dma_cmd_space = dma_cmd_space;
498
499 mac53c94_init(state);
500
501 if (request_irq(state->intr, do_mac53c94_interrupt, 0, "53C94",state)) {
502 printk(KERN_ERR "mac53C94: can't get irq %d for %s\n",
503 state->intr, node->full_name);
504 goto out_free_dma;
505 }
506
507 rc = scsi_add_host(host, &mdev->ofdev.dev);
508 if (rc != 0)
509 goto out_release_irq;
510
511 scsi_scan_host(host);
512 return 0;
513
514 out_release_irq:
515 free_irq(state->intr, state);
516 out_free_dma:
517 kfree(state->dma_cmd_space);
518 out_free:
519 if (state->dma != NULL)
520 iounmap(state->dma);
521 if (state->regs != NULL)
522 iounmap(state->regs);
523 scsi_host_put(host);
524 out_release:
525 macio_release_resources(mdev);
526
527 return rc;
528 }
529
530 static int mac53c94_remove(struct macio_dev *mdev)
531 {
532 struct fsc_state *fp = (struct fsc_state *)macio_get_drvdata(mdev);
533 struct Scsi_Host *host = fp->host;
534
535 scsi_remove_host(host);
536
537 free_irq(fp->intr, fp);
538
539 if (fp->regs)
540 iounmap(fp->regs);
541 if (fp->dma)
542 iounmap(fp->dma);
543 kfree(fp->dma_cmd_space);
544
545 scsi_host_put(host);
546
547 macio_release_resources(mdev);
548
549 return 0;
550 }
551
552
553 static struct of_device_id mac53c94_match[] =
554 {
555 {
556 .name = "53c94",
557 },
558 {},
559 };
560 MODULE_DEVICE_TABLE (of, mac53c94_match);
561
562 static struct macio_driver mac53c94_driver =
563 {
564 .name = "mac53c94",
565 .match_table = mac53c94_match,
566 .probe = mac53c94_probe,
567 .remove = mac53c94_remove,
568 };
569
570
571 static int __init init_mac53c94(void)
572 {
573 return macio_register_driver(&mac53c94_driver);
574 }
575
576 static void __exit exit_mac53c94(void)
577 {
578 return macio_unregister_driver(&mac53c94_driver);
579 }
580
581 module_init(init_mac53c94);
582 module_exit(exit_mac53c94);
583
584 MODULE_DESCRIPTION("PowerMac 53c94 SCSI driver");
585 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
586 MODULE_LICENSE("GPL");
Linux with added FPC-III support