blob: 932dcf0366ebf9a215e38defed99d05a089ae8d0 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
35enum fsc_phase {
36 idle,
37 selecting,
38 dataing,
39 completing,
40 busfreeing,
41};
42
43struct 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
61static void mac53c94_init(struct fsc_state *);
62static void mac53c94_start(struct fsc_state *);
63static void mac53c94_interrupt(int, void *, struct pt_regs *);
64static irqreturn_t do_mac53c94_interrupt(int, void *, struct pt_regs *);
65static void cmd_done(struct fsc_state *, int result);
66static void set_dma_cmds(struct fsc_state *, struct scsi_cmnd *);
67
68
69static 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101static 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;
Jeff Garzik df0ae242005-05-28 07:57:14 -0400106 unsigned long flags;
107
108 spin_lock_irqsave(cmd->device->host->host_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
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);
Jeff Garzik df0ae242005-05-28 07:57:14 -0400117
118 spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 return SUCCESS;
120}
121
122static 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 */
143static 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
180static 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
191static 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
349static 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 */
366static 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
415static struct scsi_host_template mac53c94_template = {
416 .proc_name = "53c94",
417 .name = "53C94",
418 .queuecommand = mac53c94_queue,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 .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
Jeff Mahoney5e655772005-07-06 15:44:41 -0400427static int mac53c94_probe(struct macio_dev *mdev, const struct of_device_id *match)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428{
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;
436
437 if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
438 printk(KERN_ERR "mac53c94: expected 2 addrs and intrs (got %d/%d)\n",
439 node->n_addrs, node->n_intrs);
440 return -ENODEV;
441 }
442
443 if (macio_request_resources(mdev, "mac53c94") != 0) {
444 printk(KERN_ERR "mac53c94: unable to request memory resources");
445 return -EBUSY;
446 }
447
448 host = scsi_host_alloc(&mac53c94_template, sizeof(struct fsc_state));
449 if (host == NULL) {
450 printk(KERN_ERR "mac53c94: couldn't register host");
451 goto out_release;
452 }
453
454 state = (struct fsc_state *) host->hostdata;
455 macio_set_drvdata(mdev, state);
456 state->host = host;
457 state->pdev = pdev;
458 state->mdev = mdev;
459
460 state->regs = (struct mac53c94_regs __iomem *)
461 ioremap(macio_resource_start(mdev, 0), 0x1000);
462 state->intr = macio_irq(mdev, 0);
463 state->dma = (struct dbdma_regs __iomem *)
464 ioremap(macio_resource_start(mdev, 1), 0x1000);
465 state->dmaintr = macio_irq(mdev, 1);
466 if (state->regs == NULL || state->dma == NULL) {
467 printk(KERN_ERR "mac53c94: ioremap failed for %s\n",
468 node->full_name);
469 goto out_free;
470 }
471
472 clkprop = get_property(node, "clock-frequency", &proplen);
473 if (clkprop == NULL || proplen != sizeof(int)) {
474 printk(KERN_ERR "%s: can't get clock frequency, "
475 "assuming 25MHz\n", node->full_name);
476 state->clk_freq = 25000000;
477 } else
478 state->clk_freq = *(int *)clkprop;
479
480 /* Space for dma command list: +1 for stop command,
481 * +1 to allow for aligning.
482 * XXX FIXME: Use DMA consistent routines
483 */
484 dma_cmd_space = kmalloc((host->sg_tablesize + 2) *
485 sizeof(struct dbdma_cmd), GFP_KERNEL);
486 if (dma_cmd_space == 0) {
487 printk(KERN_ERR "mac53c94: couldn't allocate dma "
488 "command space for %s\n", node->full_name);
489 goto out_free;
490 }
491 state->dma_cmds = (struct dbdma_cmd *)DBDMA_ALIGN(dma_cmd_space);
492 memset(state->dma_cmds, 0, (host->sg_tablesize + 1)
493 * sizeof(struct dbdma_cmd));
494 state->dma_cmd_space = dma_cmd_space;
495
496 mac53c94_init(state);
497
498 if (request_irq(state->intr, do_mac53c94_interrupt, 0, "53C94", state)) {
499 printk(KERN_ERR "mac53C94: can't get irq %d for %s\n",
500 state->intr, node->full_name);
501 goto out_free_dma;
502 }
503
504 /* XXX FIXME: handle failure */
505 scsi_add_host(host, &mdev->ofdev.dev);
506 scsi_scan_host(host);
507
508 return 0;
509
510 out_free_dma:
511 kfree(state->dma_cmd_space);
512 out_free:
513 if (state->dma != NULL)
514 iounmap(state->dma);
515 if (state->regs != NULL)
516 iounmap(state->regs);
517 scsi_host_put(host);
518 out_release:
519 macio_release_resources(mdev);
520
521 return -ENODEV;
522}
523
524static int mac53c94_remove(struct macio_dev *mdev)
525{
526 struct fsc_state *fp = (struct fsc_state *)macio_get_drvdata(mdev);
527 struct Scsi_Host *host = fp->host;
528
529 scsi_remove_host(host);
530
531 free_irq(fp->intr, fp);
532
533 if (fp->regs)
534 iounmap((void *) fp->regs);
535 if (fp->dma)
536 iounmap((void *) fp->dma);
537 kfree(fp->dma_cmd_space);
538
539 scsi_host_put(host);
540
541 macio_release_resources(mdev);
542
543 return 0;
544}
545
546
Jeff Mahoney5e655772005-07-06 15:44:41 -0400547static struct of_device_id mac53c94_match[] =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548{
549 {
550 .name = "53c94",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 },
552 {},
553};
Jeff Mahoney5e655772005-07-06 15:44:41 -0400554MODULE_DEVICE_TABLE (of, mac53c94_match);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555
556static struct macio_driver mac53c94_driver =
557{
558 .name = "mac53c94",
559 .match_table = mac53c94_match,
560 .probe = mac53c94_probe,
561 .remove = mac53c94_remove,
562};
563
564
565static int __init init_mac53c94(void)
566{
567 return macio_register_driver(&mac53c94_driver);
568}
569
570static void __exit exit_mac53c94(void)
571{
572 return macio_unregister_driver(&mac53c94_driver);
573}
574
575module_init(init_mac53c94);
576module_exit(exit_mac53c94);
577
578MODULE_DESCRIPTION("PowerMac 53c94 SCSI driver");
579MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
580MODULE_LICENSE("GPL");