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1 /*
2  * SCSI low-level driver for the MESH (Macintosh Enhanced SCSI Hardware)
3  * bus adaptor found on Power Macintosh computers.
4  * We assume the MESH is connected to a DBDMA (descriptor-based DMA)
5  * controller.
6  *
7  * Paul Mackerras, August 1996.
8  * Copyright (C) 1996 Paul Mackerras.
9  *
10  * Apr. 21 2002  - BenH		Rework bus reset code for new error handler
11  *                              Add delay after initial bus reset
12  *                              Add module parameters
13  *
14  * Sep. 27 2003  - BenH		Move to new driver model, fix some write posting
15  *				issues
16  * To do:
17  * - handle aborts correctly
18  * - retry arbitration if lost (unless higher levels do this for us)
19  * - power down the chip when no device is detected
20  */
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/delay.h>
24 #include <linux/types.h>
25 #include <linux/string.h>
26 #include <linux/blkdev.h>
27 #include <linux/proc_fs.h>
28 #include <linux/stat.h>
29 #include <linux/interrupt.h>
30 #include <linux/reboot.h>
31 #include <linux/spinlock.h>
32 #include <linux/pci.h>
33 #include <asm/dbdma.h>
34 #include <asm/io.h>
35 #include <asm/pgtable.h>
36 #include <asm/prom.h>
37 #include <asm/irq.h>
38 #include <asm/hydra.h>
39 #include <asm/processor.h>
40 #include <asm/machdep.h>
41 #include <asm/pmac_feature.h>
42 #include <asm/macio.h>
43 
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_cmnd.h>
46 #include <scsi/scsi_device.h>
47 #include <scsi/scsi_host.h>
48 
49 #include "mesh.h"
50 
51 #if 1
52 #undef KERN_DEBUG
53 #define KERN_DEBUG KERN_WARNING
54 #endif
55 
56 MODULE_AUTHOR("Paul Mackerras (paulus@samba.org)");
57 MODULE_DESCRIPTION("PowerMac MESH SCSI driver");
58 MODULE_LICENSE("GPL");
59 
60 static int sync_rate = CONFIG_SCSI_MESH_SYNC_RATE;
61 static int sync_targets = 0xff;
62 static int resel_targets = 0xff;
63 static int debug_targets = 0;	/* print debug for these targets */
64 static int init_reset_delay = CONFIG_SCSI_MESH_RESET_DELAY_MS;
65 
66 module_param(sync_rate, int, 0);
67 MODULE_PARM_DESC(sync_rate, "Synchronous rate (0..10, 0=async)");
68 module_param(sync_targets, int, 0);
69 MODULE_PARM_DESC(sync_targets, "Bitmask of targets allowed to set synchronous");
70 module_param(resel_targets, int, 0);
71 MODULE_PARM_DESC(resel_targets, "Bitmask of targets allowed to set disconnect");
72 module_param(debug_targets, int, 0644);
73 MODULE_PARM_DESC(debug_targets, "Bitmask of debugged targets");
74 module_param(init_reset_delay, int, 0);
75 MODULE_PARM_DESC(init_reset_delay, "Initial bus reset delay (0=no reset)");
76 
77 static int mesh_sync_period = 100;
78 static int mesh_sync_offset = 0;
79 static unsigned char use_active_neg = 0;  /* bit mask for SEQ_ACTIVE_NEG if used */
80 
81 #define ALLOW_SYNC(tgt)		((sync_targets >> (tgt)) & 1)
82 #define ALLOW_RESEL(tgt)	((resel_targets >> (tgt)) & 1)
83 #define ALLOW_DEBUG(tgt)	((debug_targets >> (tgt)) & 1)
84 #define DEBUG_TARGET(cmd)	((cmd) && ALLOW_DEBUG((cmd)->device->id))
85 
86 #undef MESH_DBG
87 #define N_DBG_LOG	50
88 #define N_DBG_SLOG	20
89 #define NUM_DBG_EVENTS	13
90 #undef	DBG_USE_TB		/* bombs on 601 */
91 
92 struct dbglog {
93 	char	*fmt;
94 	u32	tb;
95 	u8	phase;
96 	u8	bs0;
97 	u8	bs1;
98 	u8	tgt;
99 	int	d;
100 };
101 
102 enum mesh_phase {
103 	idle,
104 	arbitrating,
105 	selecting,
106 	commanding,
107 	dataing,
108 	statusing,
109 	busfreeing,
110 	disconnecting,
111 	reselecting,
112 	sleeping
113 };
114 
115 enum msg_phase {
116 	msg_none,
117 	msg_out,
118 	msg_out_xxx,
119 	msg_out_last,
120 	msg_in,
121 	msg_in_bad,
122 };
123 
124 enum sdtr_phase {
125 	do_sdtr,
126 	sdtr_sent,
127 	sdtr_done
128 };
129 
130 struct mesh_target {
131 	enum sdtr_phase sdtr_state;
132 	int	sync_params;
133 	int	data_goes_out;		/* guess as to data direction */
134 	struct scsi_cmnd *current_req;
135 	u32	saved_ptr;
136 #ifdef MESH_DBG
137 	int	log_ix;
138 	int	n_log;
139 	struct dbglog log[N_DBG_LOG];
140 #endif
141 };
142 
143 struct mesh_state {
144 	volatile struct	mesh_regs __iomem *mesh;
145 	int	meshintr;
146 	volatile struct	dbdma_regs __iomem *dma;
147 	int	dmaintr;
148 	struct	Scsi_Host *host;
149 	struct	mesh_state *next;
150 	struct scsi_cmnd *request_q;
151 	struct scsi_cmnd *request_qtail;
152 	enum mesh_phase phase;		/* what we're currently trying to do */
153 	enum msg_phase msgphase;
154 	int	conn_tgt;		/* target we're connected to */
155 	struct scsi_cmnd *current_req;		/* req we're currently working on */
156 	int	data_ptr;
157 	int	dma_started;
158 	int	dma_count;
159 	int	stat;
160 	int	aborting;
161 	int	expect_reply;
162 	int	n_msgin;
163 	u8	msgin[16];
164 	int	n_msgout;
165 	int	last_n_msgout;
166 	u8	msgout[16];
167 	struct dbdma_cmd *dma_cmds;	/* space for dbdma commands, aligned */
168 	dma_addr_t dma_cmd_bus;
169 	void	*dma_cmd_space;
170 	int	dma_cmd_size;
171 	int	clk_freq;
172 	struct mesh_target tgts[8];
173 	struct macio_dev *mdev;
174 	struct pci_dev* pdev;
175 #ifdef MESH_DBG
176 	int	log_ix;
177 	int	n_log;
178 	struct dbglog log[N_DBG_SLOG];
179 #endif
180 };
181 
182 /*
183  * Driver is too messy, we need a few prototypes...
184  */
185 static void mesh_done(struct mesh_state *ms, int start_next);
186 static void mesh_interrupt(struct mesh_state *ms);
187 static void cmd_complete(struct mesh_state *ms);
188 static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd);
189 static void halt_dma(struct mesh_state *ms);
190 static void phase_mismatch(struct mesh_state *ms);
191 
192 
193 /*
194  * Some debugging & logging routines
195  */
196 
197 #ifdef MESH_DBG
198 
readtb(void)199 static inline u32 readtb(void)
200 {
201 	u32 tb;
202 
203 #ifdef DBG_USE_TB
204 	/* Beware: if you enable this, it will crash on 601s. */
205 	asm ("mftb %0" : "=r" (tb) : );
206 #else
207 	tb = 0;
208 #endif
209 	return tb;
210 }
211 
dlog(struct mesh_state * ms,char * fmt,int a)212 static void dlog(struct mesh_state *ms, char *fmt, int a)
213 {
214 	struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
215 	struct dbglog *tlp, *slp;
216 
217 	tlp = &tp->log[tp->log_ix];
218 	slp = &ms->log[ms->log_ix];
219 	tlp->fmt = fmt;
220 	tlp->tb = readtb();
221 	tlp->phase = (ms->msgphase << 4) + ms->phase;
222 	tlp->bs0 = ms->mesh->bus_status0;
223 	tlp->bs1 = ms->mesh->bus_status1;
224 	tlp->tgt = ms->conn_tgt;
225 	tlp->d = a;
226 	*slp = *tlp;
227 	if (++tp->log_ix >= N_DBG_LOG)
228 		tp->log_ix = 0;
229 	if (tp->n_log < N_DBG_LOG)
230 		++tp->n_log;
231 	if (++ms->log_ix >= N_DBG_SLOG)
232 		ms->log_ix = 0;
233 	if (ms->n_log < N_DBG_SLOG)
234 		++ms->n_log;
235 }
236 
dumplog(struct mesh_state * ms,int t)237 static void dumplog(struct mesh_state *ms, int t)
238 {
239 	struct mesh_target *tp = &ms->tgts[t];
240 	struct dbglog *lp;
241 	int i;
242 
243 	if (tp->n_log == 0)
244 		return;
245 	i = tp->log_ix - tp->n_log;
246 	if (i < 0)
247 		i += N_DBG_LOG;
248 	tp->n_log = 0;
249 	do {
250 		lp = &tp->log[i];
251 		printk(KERN_DEBUG "mesh log %d: bs=%.2x%.2x ph=%.2x ",
252 		       t, lp->bs1, lp->bs0, lp->phase);
253 #ifdef DBG_USE_TB
254 		printk("tb=%10u ", lp->tb);
255 #endif
256 		printk(lp->fmt, lp->d);
257 		printk("\n");
258 		if (++i >= N_DBG_LOG)
259 			i = 0;
260 	} while (i != tp->log_ix);
261 }
262 
dumpslog(struct mesh_state * ms)263 static void dumpslog(struct mesh_state *ms)
264 {
265 	struct dbglog *lp;
266 	int i;
267 
268 	if (ms->n_log == 0)
269 		return;
270 	i = ms->log_ix - ms->n_log;
271 	if (i < 0)
272 		i += N_DBG_SLOG;
273 	ms->n_log = 0;
274 	do {
275 		lp = &ms->log[i];
276 		printk(KERN_DEBUG "mesh log: bs=%.2x%.2x ph=%.2x t%d ",
277 		       lp->bs1, lp->bs0, lp->phase, lp->tgt);
278 #ifdef DBG_USE_TB
279 		printk("tb=%10u ", lp->tb);
280 #endif
281 		printk(lp->fmt, lp->d);
282 		printk("\n");
283 		if (++i >= N_DBG_SLOG)
284 			i = 0;
285 	} while (i != ms->log_ix);
286 }
287 
288 #else
289 
dlog(struct mesh_state * ms,char * fmt,int a)290 static inline void dlog(struct mesh_state *ms, char *fmt, int a)
291 {}
dumplog(struct mesh_state * ms,int tgt)292 static inline void dumplog(struct mesh_state *ms, int tgt)
293 {}
dumpslog(struct mesh_state * ms)294 static inline void dumpslog(struct mesh_state *ms)
295 {}
296 
297 #endif /* MESH_DBG */
298 
299 #define MKWORD(a, b, c, d)	(((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
300 
301 static void
mesh_dump_regs(struct mesh_state * ms)302 mesh_dump_regs(struct mesh_state *ms)
303 {
304 	volatile struct mesh_regs __iomem *mr = ms->mesh;
305 	volatile struct dbdma_regs __iomem *md = ms->dma;
306 	int t;
307 	struct mesh_target *tp;
308 
309 	printk(KERN_DEBUG "mesh: state at %p, regs at %p, dma at %p\n",
310 	       ms, mr, md);
311 	printk(KERN_DEBUG "    ct=%4x seq=%2x bs=%4x fc=%2x "
312 	       "exc=%2x err=%2x im=%2x int=%2x sp=%2x\n",
313 	       (mr->count_hi << 8) + mr->count_lo, mr->sequence,
314 	       (mr->bus_status1 << 8) + mr->bus_status0, mr->fifo_count,
315 	       mr->exception, mr->error, mr->intr_mask, mr->interrupt,
316 	       mr->sync_params);
317 	while(in_8(&mr->fifo_count))
318 		printk(KERN_DEBUG " fifo data=%.2x\n",in_8(&mr->fifo));
319 	printk(KERN_DEBUG "    dma stat=%x cmdptr=%x\n",
320 	       in_le32(&md->status), in_le32(&md->cmdptr));
321 	printk(KERN_DEBUG "    phase=%d msgphase=%d conn_tgt=%d data_ptr=%d\n",
322 	       ms->phase, ms->msgphase, ms->conn_tgt, ms->data_ptr);
323 	printk(KERN_DEBUG "    dma_st=%d dma_ct=%d n_msgout=%d\n",
324 	       ms->dma_started, ms->dma_count, ms->n_msgout);
325 	for (t = 0; t < 8; ++t) {
326 		tp = &ms->tgts[t];
327 		if (tp->current_req == NULL)
328 			continue;
329 		printk(KERN_DEBUG "    target %d: req=%p goes_out=%d saved_ptr=%d\n",
330 		       t, tp->current_req, tp->data_goes_out, tp->saved_ptr);
331 	}
332 }
333 
334 
335 /*
336  * Flush write buffers on the bus path to the mesh
337  */
mesh_flush_io(volatile struct mesh_regs __iomem * mr)338 static inline void mesh_flush_io(volatile struct mesh_regs __iomem *mr)
339 {
340 	(void)in_8(&mr->mesh_id);
341 }
342 
343 
344 /*
345  * Complete a SCSI command
346  */
mesh_completed(struct mesh_state * ms,struct scsi_cmnd * cmd)347 static void mesh_completed(struct mesh_state *ms, struct scsi_cmnd *cmd)
348 {
349 	(*cmd->scsi_done)(cmd);
350 }
351 
352 
353 /* Called with  meshinterrupt disabled, initialize the chipset
354  * and eventually do the initial bus reset. The lock must not be
355  * held since we can schedule.
356  */
mesh_init(struct mesh_state * ms)357 static void mesh_init(struct mesh_state *ms)
358 {
359 	volatile struct mesh_regs __iomem *mr = ms->mesh;
360 	volatile struct dbdma_regs __iomem *md = ms->dma;
361 
362 	mesh_flush_io(mr);
363 	udelay(100);
364 
365 	/* Reset controller */
366 	out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16);	/* stop dma */
367 	out_8(&mr->exception, 0xff);	/* clear all exception bits */
368 	out_8(&mr->error, 0xff);	/* clear all error bits */
369 	out_8(&mr->sequence, SEQ_RESETMESH);
370 	mesh_flush_io(mr);
371 	udelay(10);
372 	out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
373 	out_8(&mr->source_id, ms->host->this_id);
374 	out_8(&mr->sel_timeout, 25);	/* 250ms */
375 	out_8(&mr->sync_params, ASYNC_PARAMS);
376 
377 	if (init_reset_delay) {
378 		printk(KERN_INFO "mesh: performing initial bus reset...\n");
379 
380 		/* Reset bus */
381 		out_8(&mr->bus_status1, BS1_RST);	/* assert RST */
382 		mesh_flush_io(mr);
383 		udelay(30);			/* leave it on for >= 25us */
384 		out_8(&mr->bus_status1, 0);	/* negate RST */
385 		mesh_flush_io(mr);
386 
387 		/* Wait for bus to come back */
388 		msleep(init_reset_delay);
389 	}
390 
391 	/* Reconfigure controller */
392 	out_8(&mr->interrupt, 0xff);	/* clear all interrupt bits */
393 	out_8(&mr->sequence, SEQ_FLUSHFIFO);
394 	mesh_flush_io(mr);
395 	udelay(1);
396 	out_8(&mr->sync_params, ASYNC_PARAMS);
397 	out_8(&mr->sequence, SEQ_ENBRESEL);
398 
399 	ms->phase = idle;
400 	ms->msgphase = msg_none;
401 }
402 
403 
mesh_start_cmd(struct mesh_state * ms,struct scsi_cmnd * cmd)404 static void mesh_start_cmd(struct mesh_state *ms, struct scsi_cmnd *cmd)
405 {
406 	volatile struct mesh_regs __iomem *mr = ms->mesh;
407 	int t, id;
408 
409 	id = cmd->device->id;
410 	ms->current_req = cmd;
411 	ms->tgts[id].data_goes_out = cmd->sc_data_direction == DMA_TO_DEVICE;
412 	ms->tgts[id].current_req = cmd;
413 
414 #if 1
415 	if (DEBUG_TARGET(cmd)) {
416 		int i;
417 		printk(KERN_DEBUG "mesh_start: %p tgt=%d cmd=", cmd, id);
418 		for (i = 0; i < cmd->cmd_len; ++i)
419 			printk(" %x", cmd->cmnd[i]);
420 		printk(" use_sg=%d buffer=%p bufflen=%u\n",
421 		       scsi_sg_count(cmd), scsi_sglist(cmd), scsi_bufflen(cmd));
422 	}
423 #endif
424 	if (ms->dma_started)
425 		panic("mesh: double DMA start !\n");
426 
427 	ms->phase = arbitrating;
428 	ms->msgphase = msg_none;
429 	ms->data_ptr = 0;
430 	ms->dma_started = 0;
431 	ms->n_msgout = 0;
432 	ms->last_n_msgout = 0;
433 	ms->expect_reply = 0;
434 	ms->conn_tgt = id;
435 	ms->tgts[id].saved_ptr = 0;
436 	ms->stat = DID_OK;
437 	ms->aborting = 0;
438 #ifdef MESH_DBG
439 	ms->tgts[id].n_log = 0;
440 	dlog(ms, "start cmd=%x", (int) cmd);
441 #endif
442 
443 	/* Off we go */
444 	dlog(ms, "about to arb, intr/exc/err/fc=%.8x",
445 	     MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
446 	out_8(&mr->interrupt, INT_CMDDONE);
447 	out_8(&mr->sequence, SEQ_ENBRESEL);
448 	mesh_flush_io(mr);
449 	udelay(1);
450 
451 	if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
452 		/*
453 		 * Some other device has the bus or is arbitrating for it -
454 		 * probably a target which is about to reselect us.
455 		 */
456 		dlog(ms, "busy b4 arb, intr/exc/err/fc=%.8x",
457 		     MKWORD(mr->interrupt, mr->exception,
458 			    mr->error, mr->fifo_count));
459 		for (t = 100; t > 0; --t) {
460 			if ((in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) == 0)
461 				break;
462 			if (in_8(&mr->interrupt) != 0) {
463 				dlog(ms, "intr b4 arb, intr/exc/err/fc=%.8x",
464 				     MKWORD(mr->interrupt, mr->exception,
465 					    mr->error, mr->fifo_count));
466 				mesh_interrupt(ms);
467 				if (ms->phase != arbitrating)
468 					return;
469 			}
470 			udelay(1);
471 		}
472 		if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
473 			/* XXX should try again in a little while */
474 			ms->stat = DID_BUS_BUSY;
475 			ms->phase = idle;
476 			mesh_done(ms, 0);
477 			return;
478 		}
479 	}
480 
481 	/*
482 	 * Apparently the mesh has a bug where it will assert both its
483 	 * own bit and the target's bit on the bus during arbitration.
484 	 */
485 	out_8(&mr->dest_id, mr->source_id);
486 
487 	/*
488 	 * There appears to be a race with reselection sometimes,
489 	 * where a target reselects us just as we issue the
490 	 * arbitrate command.  It seems that then the arbitrate
491 	 * command just hangs waiting for the bus to be free
492 	 * without giving us a reselection exception.
493 	 * The only way I have found to get it to respond correctly
494 	 * is this: disable reselection before issuing the arbitrate
495 	 * command, then after issuing it, if it looks like a target
496 	 * is trying to reselect us, reset the mesh and then enable
497 	 * reselection.
498 	 */
499 	out_8(&mr->sequence, SEQ_DISRESEL);
500 	if (in_8(&mr->interrupt) != 0) {
501 		dlog(ms, "intr after disresel, intr/exc/err/fc=%.8x",
502 		     MKWORD(mr->interrupt, mr->exception,
503 			    mr->error, mr->fifo_count));
504 		mesh_interrupt(ms);
505 		if (ms->phase != arbitrating)
506 			return;
507 		dlog(ms, "after intr after disresel, intr/exc/err/fc=%.8x",
508 		     MKWORD(mr->interrupt, mr->exception,
509 			    mr->error, mr->fifo_count));
510 	}
511 
512 	out_8(&mr->sequence, SEQ_ARBITRATE);
513 
514 	for (t = 230; t > 0; --t) {
515 		if (in_8(&mr->interrupt) != 0)
516 			break;
517 		udelay(1);
518 	}
519 	dlog(ms, "after arb, intr/exc/err/fc=%.8x",
520 	     MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
521 	if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
522 	    && (in_8(&mr->bus_status0) & BS0_IO)) {
523 		/* looks like a reselection - try resetting the mesh */
524 		dlog(ms, "resel? after arb, intr/exc/err/fc=%.8x",
525 		     MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
526 		out_8(&mr->sequence, SEQ_RESETMESH);
527 		mesh_flush_io(mr);
528 		udelay(10);
529 		out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
530 		out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
531 		out_8(&mr->sequence, SEQ_ENBRESEL);
532 		mesh_flush_io(mr);
533 		for (t = 10; t > 0 && in_8(&mr->interrupt) == 0; --t)
534 			udelay(1);
535 		dlog(ms, "tried reset after arb, intr/exc/err/fc=%.8x",
536 		     MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
537 #ifndef MESH_MULTIPLE_HOSTS
538 		if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
539 		    && (in_8(&mr->bus_status0) & BS0_IO)) {
540 			printk(KERN_ERR "mesh: controller not responding"
541 			       " to reselection!\n");
542 			/*
543 			 * If this is a target reselecting us, and the
544 			 * mesh isn't responding, the higher levels of
545 			 * the scsi code will eventually time out and
546 			 * reset the bus.
547 			 */
548 		}
549 #endif
550 	}
551 }
552 
553 /*
554  * Start the next command for a MESH.
555  * Should be called with interrupts disabled.
556  */
mesh_start(struct mesh_state * ms)557 static void mesh_start(struct mesh_state *ms)
558 {
559 	struct scsi_cmnd *cmd, *prev, *next;
560 
561 	if (ms->phase != idle || ms->current_req != NULL) {
562 		printk(KERN_ERR "inappropriate mesh_start (phase=%d, ms=%p)",
563 		       ms->phase, ms);
564 		return;
565 	}
566 
567 	while (ms->phase == idle) {
568 		prev = NULL;
569 		for (cmd = ms->request_q; ; cmd = (struct scsi_cmnd *) cmd->host_scribble) {
570 			if (cmd == NULL)
571 				return;
572 			if (ms->tgts[cmd->device->id].current_req == NULL)
573 				break;
574 			prev = cmd;
575 		}
576 		next = (struct scsi_cmnd *) cmd->host_scribble;
577 		if (prev == NULL)
578 			ms->request_q = next;
579 		else
580 			prev->host_scribble = (void *) next;
581 		if (next == NULL)
582 			ms->request_qtail = prev;
583 
584 		mesh_start_cmd(ms, cmd);
585 	}
586 }
587 
mesh_done(struct mesh_state * ms,int start_next)588 static void mesh_done(struct mesh_state *ms, int start_next)
589 {
590 	struct scsi_cmnd *cmd;
591 	struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
592 
593 	cmd = ms->current_req;
594 	ms->current_req = NULL;
595 	tp->current_req = NULL;
596 	if (cmd) {
597 		cmd->result = (ms->stat << 16) + cmd->SCp.Status;
598 		if (ms->stat == DID_OK)
599 			cmd->result += (cmd->SCp.Message << 8);
600 		if (DEBUG_TARGET(cmd)) {
601 			printk(KERN_DEBUG "mesh_done: result = %x, data_ptr=%d, buflen=%d\n",
602 			       cmd->result, ms->data_ptr, scsi_bufflen(cmd));
603 #if 0
604 			/* needs to use sg? */
605 			if ((cmd->cmnd[0] == 0 || cmd->cmnd[0] == 0x12 || cmd->cmnd[0] == 3)
606 			    && cmd->request_buffer != 0) {
607 				unsigned char *b = cmd->request_buffer;
608 				printk(KERN_DEBUG "buffer = %x %x %x %x %x %x %x %x\n",
609 				       b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7]);
610 			}
611 #endif
612 		}
613 		cmd->SCp.this_residual -= ms->data_ptr;
614 		mesh_completed(ms, cmd);
615 	}
616 	if (start_next) {
617 		out_8(&ms->mesh->sequence, SEQ_ENBRESEL);
618 		mesh_flush_io(ms->mesh);
619 		udelay(1);
620 		ms->phase = idle;
621 		mesh_start(ms);
622 	}
623 }
624 
add_sdtr_msg(struct mesh_state * ms)625 static inline void add_sdtr_msg(struct mesh_state *ms)
626 {
627 	int i = ms->n_msgout;
628 
629 	ms->msgout[i] = EXTENDED_MESSAGE;
630 	ms->msgout[i+1] = 3;
631 	ms->msgout[i+2] = EXTENDED_SDTR;
632 	ms->msgout[i+3] = mesh_sync_period/4;
633 	ms->msgout[i+4] = (ALLOW_SYNC(ms->conn_tgt)? mesh_sync_offset: 0);
634 	ms->n_msgout = i + 5;
635 }
636 
set_sdtr(struct mesh_state * ms,int period,int offset)637 static void set_sdtr(struct mesh_state *ms, int period, int offset)
638 {
639 	struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
640 	volatile struct mesh_regs __iomem *mr = ms->mesh;
641 	int v, tr;
642 
643 	tp->sdtr_state = sdtr_done;
644 	if (offset == 0) {
645 		/* asynchronous */
646 		if (SYNC_OFF(tp->sync_params))
647 			printk(KERN_INFO "mesh: target %d now asynchronous\n",
648 			       ms->conn_tgt);
649 		tp->sync_params = ASYNC_PARAMS;
650 		out_8(&mr->sync_params, ASYNC_PARAMS);
651 		return;
652 	}
653 	/*
654 	 * We need to compute ceil(clk_freq * period / 500e6) - 2
655 	 * without incurring overflow.
656 	 */
657 	v = (ms->clk_freq / 5000) * period;
658 	if (v <= 250000) {
659 		/* special case: sync_period == 5 * clk_period */
660 		v = 0;
661 		/* units of tr are 100kB/s */
662 		tr = (ms->clk_freq + 250000) / 500000;
663 	} else {
664 		/* sync_period == (v + 2) * 2 * clk_period */
665 		v = (v + 99999) / 100000 - 2;
666 		if (v > 15)
667 			v = 15;	/* oops */
668 		tr = ((ms->clk_freq / (v + 2)) + 199999) / 200000;
669 	}
670 	if (offset > 15)
671 		offset = 15;	/* can't happen */
672 	tp->sync_params = SYNC_PARAMS(offset, v);
673 	out_8(&mr->sync_params, tp->sync_params);
674 	printk(KERN_INFO "mesh: target %d synchronous at %d.%d MB/s\n",
675 	       ms->conn_tgt, tr/10, tr%10);
676 }
677 
start_phase(struct mesh_state * ms)678 static void start_phase(struct mesh_state *ms)
679 {
680 	int i, seq, nb;
681 	volatile struct mesh_regs __iomem *mr = ms->mesh;
682 	volatile struct dbdma_regs __iomem *md = ms->dma;
683 	struct scsi_cmnd *cmd = ms->current_req;
684 	struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
685 
686 	dlog(ms, "start_phase nmo/exc/fc/seq = %.8x",
687 	     MKWORD(ms->n_msgout, mr->exception, mr->fifo_count, mr->sequence));
688 	out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
689 	seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
690 	switch (ms->msgphase) {
691 	case msg_none:
692 		break;
693 
694 	case msg_in:
695 		out_8(&mr->count_hi, 0);
696 		out_8(&mr->count_lo, 1);
697 		out_8(&mr->sequence, SEQ_MSGIN + seq);
698 		ms->n_msgin = 0;
699 		return;
700 
701 	case msg_out:
702 		/*
703 		 * To make sure ATN drops before we assert ACK for
704 		 * the last byte of the message, we have to do the
705 		 * last byte specially.
706 		 */
707 		if (ms->n_msgout <= 0) {
708 			printk(KERN_ERR "mesh: msg_out but n_msgout=%d\n",
709 			       ms->n_msgout);
710 			mesh_dump_regs(ms);
711 			ms->msgphase = msg_none;
712 			break;
713 		}
714 		if (ALLOW_DEBUG(ms->conn_tgt)) {
715 			printk(KERN_DEBUG "mesh: sending %d msg bytes:",
716 			       ms->n_msgout);
717 			for (i = 0; i < ms->n_msgout; ++i)
718 				printk(" %x", ms->msgout[i]);
719 			printk("\n");
720 		}
721 		dlog(ms, "msgout msg=%.8x", MKWORD(ms->n_msgout, ms->msgout[0],
722 						ms->msgout[1], ms->msgout[2]));
723 		out_8(&mr->count_hi, 0);
724 		out_8(&mr->sequence, SEQ_FLUSHFIFO);
725 		mesh_flush_io(mr);
726 		udelay(1);
727 		/*
728 		 * If ATN is not already asserted, we assert it, then
729 		 * issue a SEQ_MSGOUT to get the mesh to drop ACK.
730 		 */
731 		if ((in_8(&mr->bus_status0) & BS0_ATN) == 0) {
732 			dlog(ms, "bus0 was %.2x explicitly asserting ATN", mr->bus_status0);
733 			out_8(&mr->bus_status0, BS0_ATN); /* explicit ATN */
734 			mesh_flush_io(mr);
735 			udelay(1);
736 			out_8(&mr->count_lo, 1);
737 			out_8(&mr->sequence, SEQ_MSGOUT + seq);
738 			out_8(&mr->bus_status0, 0); /* release explicit ATN */
739 			dlog(ms,"hace: after explicit ATN bus0=%.2x",mr->bus_status0);
740 		}
741 		if (ms->n_msgout == 1) {
742 			/*
743 			 * We can't issue the SEQ_MSGOUT without ATN
744 			 * until the target has asserted REQ.  The logic
745 			 * in cmd_complete handles both situations:
746 			 * REQ already asserted or not.
747 			 */
748 			cmd_complete(ms);
749 		} else {
750 			out_8(&mr->count_lo, ms->n_msgout - 1);
751 			out_8(&mr->sequence, SEQ_MSGOUT + seq);
752 			for (i = 0; i < ms->n_msgout - 1; ++i)
753 				out_8(&mr->fifo, ms->msgout[i]);
754 		}
755 		return;
756 
757 	default:
758 		printk(KERN_ERR "mesh bug: start_phase msgphase=%d\n",
759 		       ms->msgphase);
760 	}
761 
762 	switch (ms->phase) {
763 	case selecting:
764 		out_8(&mr->dest_id, ms->conn_tgt);
765 		out_8(&mr->sequence, SEQ_SELECT + SEQ_ATN);
766 		break;
767 	case commanding:
768 		out_8(&mr->sync_params, tp->sync_params);
769 		out_8(&mr->count_hi, 0);
770 		if (cmd) {
771 			out_8(&mr->count_lo, cmd->cmd_len);
772 			out_8(&mr->sequence, SEQ_COMMAND + seq);
773 			for (i = 0; i < cmd->cmd_len; ++i)
774 				out_8(&mr->fifo, cmd->cmnd[i]);
775 		} else {
776 			out_8(&mr->count_lo, 6);
777 			out_8(&mr->sequence, SEQ_COMMAND + seq);
778 			for (i = 0; i < 6; ++i)
779 				out_8(&mr->fifo, 0);
780 		}
781 		break;
782 	case dataing:
783 		/* transfer data, if any */
784 		if (!ms->dma_started) {
785 			set_dma_cmds(ms, cmd);
786 			out_le32(&md->cmdptr, virt_to_phys(ms->dma_cmds));
787 			out_le32(&md->control, (RUN << 16) | RUN);
788 			ms->dma_started = 1;
789 		}
790 		nb = ms->dma_count;
791 		if (nb > 0xfff0)
792 			nb = 0xfff0;
793 		ms->dma_count -= nb;
794 		ms->data_ptr += nb;
795 		out_8(&mr->count_lo, nb);
796 		out_8(&mr->count_hi, nb >> 8);
797 		out_8(&mr->sequence, (tp->data_goes_out?
798 				SEQ_DATAOUT: SEQ_DATAIN) + SEQ_DMA_MODE + seq);
799 		break;
800 	case statusing:
801 		out_8(&mr->count_hi, 0);
802 		out_8(&mr->count_lo, 1);
803 		out_8(&mr->sequence, SEQ_STATUS + seq);
804 		break;
805 	case busfreeing:
806 	case disconnecting:
807 		out_8(&mr->sequence, SEQ_ENBRESEL);
808 		mesh_flush_io(mr);
809 		udelay(1);
810 		dlog(ms, "enbresel intr/exc/err/fc=%.8x",
811 		     MKWORD(mr->interrupt, mr->exception, mr->error,
812 			    mr->fifo_count));
813 		out_8(&mr->sequence, SEQ_BUSFREE);
814 		break;
815 	default:
816 		printk(KERN_ERR "mesh: start_phase called with phase=%d\n",
817 		       ms->phase);
818 		dumpslog(ms);
819 	}
820 
821 }
822 
get_msgin(struct mesh_state * ms)823 static inline void get_msgin(struct mesh_state *ms)
824 {
825 	volatile struct mesh_regs __iomem *mr = ms->mesh;
826 	int i, n;
827 
828 	n = mr->fifo_count;
829 	if (n != 0) {
830 		i = ms->n_msgin;
831 		ms->n_msgin = i + n;
832 		for (; n > 0; --n)
833 			ms->msgin[i++] = in_8(&mr->fifo);
834 	}
835 }
836 
msgin_length(struct mesh_state * ms)837 static inline int msgin_length(struct mesh_state *ms)
838 {
839 	int b, n;
840 
841 	n = 1;
842 	if (ms->n_msgin > 0) {
843 		b = ms->msgin[0];
844 		if (b == 1) {
845 			/* extended message */
846 			n = ms->n_msgin < 2? 2: ms->msgin[1] + 2;
847 		} else if (0x20 <= b && b <= 0x2f) {
848 			/* 2-byte message */
849 			n = 2;
850 		}
851 	}
852 	return n;
853 }
854 
reselected(struct mesh_state * ms)855 static void reselected(struct mesh_state *ms)
856 {
857 	volatile struct mesh_regs __iomem *mr = ms->mesh;
858 	struct scsi_cmnd *cmd;
859 	struct mesh_target *tp;
860 	int b, t, prev;
861 
862 	switch (ms->phase) {
863 	case idle:
864 		break;
865 	case arbitrating:
866 		if ((cmd = ms->current_req) != NULL) {
867 			/* put the command back on the queue */
868 			cmd->host_scribble = (void *) ms->request_q;
869 			if (ms->request_q == NULL)
870 				ms->request_qtail = cmd;
871 			ms->request_q = cmd;
872 			tp = &ms->tgts[cmd->device->id];
873 			tp->current_req = NULL;
874 		}
875 		break;
876 	case busfreeing:
877 		ms->phase = reselecting;
878 		mesh_done(ms, 0);
879 		break;
880 	case disconnecting:
881 		break;
882 	default:
883 		printk(KERN_ERR "mesh: reselected in phase %d/%d tgt %d\n",
884 		       ms->msgphase, ms->phase, ms->conn_tgt);
885 		dumplog(ms, ms->conn_tgt);
886 		dumpslog(ms);
887 	}
888 
889 	if (ms->dma_started) {
890 		printk(KERN_ERR "mesh: reselected with DMA started !\n");
891 		halt_dma(ms);
892 	}
893 	ms->current_req = NULL;
894 	ms->phase = dataing;
895 	ms->msgphase = msg_in;
896 	ms->n_msgout = 0;
897 	ms->last_n_msgout = 0;
898 	prev = ms->conn_tgt;
899 
900 	/*
901 	 * We seem to get abortive reselections sometimes.
902 	 */
903 	while ((in_8(&mr->bus_status1) & BS1_BSY) == 0) {
904 		static int mesh_aborted_resels;
905 		mesh_aborted_resels++;
906 		out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
907 		mesh_flush_io(mr);
908 		udelay(1);
909 		out_8(&mr->sequence, SEQ_ENBRESEL);
910 		mesh_flush_io(mr);
911 		udelay(5);
912 		dlog(ms, "extra resel err/exc/fc = %.6x",
913 		     MKWORD(0, mr->error, mr->exception, mr->fifo_count));
914 	}
915 	out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
916        	mesh_flush_io(mr);
917 	udelay(1);
918 	out_8(&mr->sequence, SEQ_ENBRESEL);
919        	mesh_flush_io(mr);
920 	udelay(1);
921 	out_8(&mr->sync_params, ASYNC_PARAMS);
922 
923 	/*
924 	 * Find out who reselected us.
925 	 */
926 	if (in_8(&mr->fifo_count) == 0) {
927 		printk(KERN_ERR "mesh: reselection but nothing in fifo?\n");
928 		ms->conn_tgt = ms->host->this_id;
929 		goto bogus;
930 	}
931 	/* get the last byte in the fifo */
932 	do {
933 		b = in_8(&mr->fifo);
934 		dlog(ms, "reseldata %x", b);
935 	} while (in_8(&mr->fifo_count));
936 	for (t = 0; t < 8; ++t)
937 		if ((b & (1 << t)) != 0 && t != ms->host->this_id)
938 			break;
939 	if (b != (1 << t) + (1 << ms->host->this_id)) {
940 		printk(KERN_ERR "mesh: bad reselection data %x\n", b);
941 		ms->conn_tgt = ms->host->this_id;
942 		goto bogus;
943 	}
944 
945 
946 	/*
947 	 * Set up to continue with that target's transfer.
948 	 */
949 	ms->conn_tgt = t;
950 	tp = &ms->tgts[t];
951 	out_8(&mr->sync_params, tp->sync_params);
952 	if (ALLOW_DEBUG(t)) {
953 		printk(KERN_DEBUG "mesh: reselected by target %d\n", t);
954 		printk(KERN_DEBUG "mesh: saved_ptr=%x goes_out=%d cmd=%p\n",
955 		       tp->saved_ptr, tp->data_goes_out, tp->current_req);
956 	}
957 	ms->current_req = tp->current_req;
958 	if (tp->current_req == NULL) {
959 		printk(KERN_ERR "mesh: reselected by tgt %d but no cmd!\n", t);
960 		goto bogus;
961 	}
962 	ms->data_ptr = tp->saved_ptr;
963 	dlog(ms, "resel prev tgt=%d", prev);
964 	dlog(ms, "resel err/exc=%.4x", MKWORD(0, 0, mr->error, mr->exception));
965 	start_phase(ms);
966 	return;
967 
968 bogus:
969 	dumplog(ms, ms->conn_tgt);
970 	dumpslog(ms);
971 	ms->data_ptr = 0;
972 	ms->aborting = 1;
973 	start_phase(ms);
974 }
975 
do_abort(struct mesh_state * ms)976 static void do_abort(struct mesh_state *ms)
977 {
978 	ms->msgout[0] = ABORT;
979 	ms->n_msgout = 1;
980 	ms->aborting = 1;
981 	ms->stat = DID_ABORT;
982 	dlog(ms, "abort", 0);
983 }
984 
handle_reset(struct mesh_state * ms)985 static void handle_reset(struct mesh_state *ms)
986 {
987 	int tgt;
988 	struct mesh_target *tp;
989 	struct scsi_cmnd *cmd;
990 	volatile struct mesh_regs __iomem *mr = ms->mesh;
991 
992 	for (tgt = 0; tgt < 8; ++tgt) {
993 		tp = &ms->tgts[tgt];
994 		if ((cmd = tp->current_req) != NULL) {
995 			cmd->result = DID_RESET << 16;
996 			tp->current_req = NULL;
997 			mesh_completed(ms, cmd);
998 		}
999 		ms->tgts[tgt].sdtr_state = do_sdtr;
1000 		ms->tgts[tgt].sync_params = ASYNC_PARAMS;
1001 	}
1002 	ms->current_req = NULL;
1003 	while ((cmd = ms->request_q) != NULL) {
1004 		ms->request_q = (struct scsi_cmnd *) cmd->host_scribble;
1005 		cmd->result = DID_RESET << 16;
1006 		mesh_completed(ms, cmd);
1007 	}
1008 	ms->phase = idle;
1009 	ms->msgphase = msg_none;
1010 	out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1011 	out_8(&mr->sequence, SEQ_FLUSHFIFO);
1012        	mesh_flush_io(mr);
1013 	udelay(1);
1014 	out_8(&mr->sync_params, ASYNC_PARAMS);
1015 	out_8(&mr->sequence, SEQ_ENBRESEL);
1016 }
1017 
do_mesh_interrupt(int irq,void * dev_id)1018 static irqreturn_t do_mesh_interrupt(int irq, void *dev_id)
1019 {
1020 	unsigned long flags;
1021 	struct mesh_state *ms = dev_id;
1022 	struct Scsi_Host *dev = ms->host;
1023 
1024 	spin_lock_irqsave(dev->host_lock, flags);
1025 	mesh_interrupt(ms);
1026 	spin_unlock_irqrestore(dev->host_lock, flags);
1027 	return IRQ_HANDLED;
1028 }
1029 
handle_error(struct mesh_state * ms)1030 static void handle_error(struct mesh_state *ms)
1031 {
1032 	int err, exc, count;
1033 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1034 
1035 	err = in_8(&mr->error);
1036 	exc = in_8(&mr->exception);
1037 	out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1038 	dlog(ms, "error err/exc/fc/cl=%.8x",
1039 	     MKWORD(err, exc, mr->fifo_count, mr->count_lo));
1040 	if (err & ERR_SCSIRESET) {
1041 		/* SCSI bus was reset */
1042 		printk(KERN_INFO "mesh: SCSI bus reset detected: "
1043 		       "waiting for end...");
1044 		while ((in_8(&mr->bus_status1) & BS1_RST) != 0)
1045 			udelay(1);
1046 		printk("done\n");
1047 		handle_reset(ms);
1048 		/* request_q is empty, no point in mesh_start() */
1049 		return;
1050 	}
1051 	if (err & ERR_UNEXPDISC) {
1052 		/* Unexpected disconnect */
1053 		if (exc & EXC_RESELECTED) {
1054 			reselected(ms);
1055 			return;
1056 		}
1057 		if (!ms->aborting) {
1058 			printk(KERN_WARNING "mesh: target %d aborted\n",
1059 			       ms->conn_tgt);
1060 			dumplog(ms, ms->conn_tgt);
1061 			dumpslog(ms);
1062 		}
1063 		out_8(&mr->interrupt, INT_CMDDONE);
1064 		ms->stat = DID_ABORT;
1065 		mesh_done(ms, 1);
1066 		return;
1067 	}
1068 	if (err & ERR_PARITY) {
1069 		if (ms->msgphase == msg_in) {
1070 			printk(KERN_ERR "mesh: msg parity error, target %d\n",
1071 			       ms->conn_tgt);
1072 			ms->msgout[0] = MSG_PARITY_ERROR;
1073 			ms->n_msgout = 1;
1074 			ms->msgphase = msg_in_bad;
1075 			cmd_complete(ms);
1076 			return;
1077 		}
1078 		if (ms->stat == DID_OK) {
1079 			printk(KERN_ERR "mesh: parity error, target %d\n",
1080 			       ms->conn_tgt);
1081 			ms->stat = DID_PARITY;
1082 		}
1083 		count = (mr->count_hi << 8) + mr->count_lo;
1084 		if (count == 0) {
1085 			cmd_complete(ms);
1086 		} else {
1087 			/* reissue the data transfer command */
1088 			out_8(&mr->sequence, mr->sequence);
1089 		}
1090 		return;
1091 	}
1092 	if (err & ERR_SEQERR) {
1093 		if (exc & EXC_RESELECTED) {
1094 			/* This can happen if we issue a command to
1095 			   get the bus just after the target reselects us. */
1096 			static int mesh_resel_seqerr;
1097 			mesh_resel_seqerr++;
1098 			reselected(ms);
1099 			return;
1100 		}
1101 		if (exc == EXC_PHASEMM) {
1102 			static int mesh_phasemm_seqerr;
1103 			mesh_phasemm_seqerr++;
1104 			phase_mismatch(ms);
1105 			return;
1106 		}
1107 		printk(KERN_ERR "mesh: sequence error (err=%x exc=%x)\n",
1108 		       err, exc);
1109 	} else {
1110 		printk(KERN_ERR "mesh: unknown error %x (exc=%x)\n", err, exc);
1111 	}
1112 	mesh_dump_regs(ms);
1113 	dumplog(ms, ms->conn_tgt);
1114 	if (ms->phase > selecting && (in_8(&mr->bus_status1) & BS1_BSY)) {
1115 		/* try to do what the target wants */
1116 		do_abort(ms);
1117 		phase_mismatch(ms);
1118 		return;
1119 	}
1120 	ms->stat = DID_ERROR;
1121 	mesh_done(ms, 1);
1122 }
1123 
handle_exception(struct mesh_state * ms)1124 static void handle_exception(struct mesh_state *ms)
1125 {
1126 	int exc;
1127 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1128 
1129 	exc = in_8(&mr->exception);
1130 	out_8(&mr->interrupt, INT_EXCEPTION | INT_CMDDONE);
1131 	if (exc & EXC_RESELECTED) {
1132 		static int mesh_resel_exc;
1133 		mesh_resel_exc++;
1134 		reselected(ms);
1135 	} else if (exc == EXC_ARBLOST) {
1136 		printk(KERN_DEBUG "mesh: lost arbitration\n");
1137 		ms->stat = DID_BUS_BUSY;
1138 		mesh_done(ms, 1);
1139 	} else if (exc == EXC_SELTO) {
1140 		/* selection timed out */
1141 		ms->stat = DID_BAD_TARGET;
1142 		mesh_done(ms, 1);
1143 	} else if (exc == EXC_PHASEMM) {
1144 		/* target wants to do something different:
1145 		   find out what it wants and do it. */
1146 		phase_mismatch(ms);
1147 	} else {
1148 		printk(KERN_ERR "mesh: can't cope with exception %x\n", exc);
1149 		mesh_dump_regs(ms);
1150 		dumplog(ms, ms->conn_tgt);
1151 		do_abort(ms);
1152 		phase_mismatch(ms);
1153 	}
1154 }
1155 
handle_msgin(struct mesh_state * ms)1156 static void handle_msgin(struct mesh_state *ms)
1157 {
1158 	int i, code;
1159 	struct scsi_cmnd *cmd = ms->current_req;
1160 	struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
1161 
1162 	if (ms->n_msgin == 0)
1163 		return;
1164 	code = ms->msgin[0];
1165 	if (ALLOW_DEBUG(ms->conn_tgt)) {
1166 		printk(KERN_DEBUG "got %d message bytes:", ms->n_msgin);
1167 		for (i = 0; i < ms->n_msgin; ++i)
1168 			printk(" %x", ms->msgin[i]);
1169 		printk("\n");
1170 	}
1171 	dlog(ms, "msgin msg=%.8x",
1172 	     MKWORD(ms->n_msgin, code, ms->msgin[1], ms->msgin[2]));
1173 
1174 	ms->expect_reply = 0;
1175 	ms->n_msgout = 0;
1176 	if (ms->n_msgin < msgin_length(ms))
1177 		goto reject;
1178 	if (cmd)
1179 		cmd->SCp.Message = code;
1180 	switch (code) {
1181 	case COMMAND_COMPLETE:
1182 		break;
1183 	case EXTENDED_MESSAGE:
1184 		switch (ms->msgin[2]) {
1185 		case EXTENDED_MODIFY_DATA_POINTER:
1186 			ms->data_ptr += (ms->msgin[3] << 24) + ms->msgin[6]
1187 				+ (ms->msgin[4] << 16) + (ms->msgin[5] << 8);
1188 			break;
1189 		case EXTENDED_SDTR:
1190 			if (tp->sdtr_state != sdtr_sent) {
1191 				/* reply with an SDTR */
1192 				add_sdtr_msg(ms);
1193 				/* limit period to at least his value,
1194 				   offset to no more than his */
1195 				if (ms->msgout[3] < ms->msgin[3])
1196 					ms->msgout[3] = ms->msgin[3];
1197 				if (ms->msgout[4] > ms->msgin[4])
1198 					ms->msgout[4] = ms->msgin[4];
1199 				set_sdtr(ms, ms->msgout[3], ms->msgout[4]);
1200 				ms->msgphase = msg_out;
1201 			} else {
1202 				set_sdtr(ms, ms->msgin[3], ms->msgin[4]);
1203 			}
1204 			break;
1205 		default:
1206 			goto reject;
1207 		}
1208 		break;
1209 	case SAVE_POINTERS:
1210 		tp->saved_ptr = ms->data_ptr;
1211 		break;
1212 	case RESTORE_POINTERS:
1213 		ms->data_ptr = tp->saved_ptr;
1214 		break;
1215 	case DISCONNECT:
1216 		ms->phase = disconnecting;
1217 		break;
1218 	case ABORT:
1219 		break;
1220 	case MESSAGE_REJECT:
1221 		if (tp->sdtr_state == sdtr_sent)
1222 			set_sdtr(ms, 0, 0);
1223 		break;
1224 	case NOP:
1225 		break;
1226 	default:
1227 		if (IDENTIFY_BASE <= code && code <= IDENTIFY_BASE + 7) {
1228 			if (cmd == NULL) {
1229 				do_abort(ms);
1230 				ms->msgphase = msg_out;
1231 			} else if (code != cmd->device->lun + IDENTIFY_BASE) {
1232 				printk(KERN_WARNING "mesh: lun mismatch "
1233 				       "(%d != %llu) on reselection from "
1234 				       "target %d\n", code - IDENTIFY_BASE,
1235 				       cmd->device->lun, ms->conn_tgt);
1236 			}
1237 			break;
1238 		}
1239 		goto reject;
1240 	}
1241 	return;
1242 
1243  reject:
1244 	printk(KERN_WARNING "mesh: rejecting message from target %d:",
1245 	       ms->conn_tgt);
1246 	for (i = 0; i < ms->n_msgin; ++i)
1247 		printk(" %x", ms->msgin[i]);
1248 	printk("\n");
1249 	ms->msgout[0] = MESSAGE_REJECT;
1250 	ms->n_msgout = 1;
1251 	ms->msgphase = msg_out;
1252 }
1253 
1254 /*
1255  * Set up DMA commands for transferring data.
1256  */
set_dma_cmds(struct mesh_state * ms,struct scsi_cmnd * cmd)1257 static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd)
1258 {
1259 	int i, dma_cmd, total, off, dtot;
1260 	struct scatterlist *scl;
1261 	struct dbdma_cmd *dcmds;
1262 
1263 	dma_cmd = ms->tgts[ms->conn_tgt].data_goes_out?
1264 		OUTPUT_MORE: INPUT_MORE;
1265 	dcmds = ms->dma_cmds;
1266 	dtot = 0;
1267 	if (cmd) {
1268 		int nseg;
1269 
1270 		cmd->SCp.this_residual = scsi_bufflen(cmd);
1271 
1272 		nseg = scsi_dma_map(cmd);
1273 		BUG_ON(nseg < 0);
1274 
1275 		if (nseg) {
1276 			total = 0;
1277 			off = ms->data_ptr;
1278 
1279 			scsi_for_each_sg(cmd, scl, nseg, i) {
1280 				u32 dma_addr = sg_dma_address(scl);
1281 				u32 dma_len = sg_dma_len(scl);
1282 
1283 				total += scl->length;
1284 				if (off >= dma_len) {
1285 					off -= dma_len;
1286 					continue;
1287 				}
1288 				if (dma_len > 0xffff)
1289 					panic("mesh: scatterlist element >= 64k");
1290 				dcmds->req_count = cpu_to_le16(dma_len - off);
1291 				dcmds->command = cpu_to_le16(dma_cmd);
1292 				dcmds->phy_addr = cpu_to_le32(dma_addr + off);
1293 				dcmds->xfer_status = 0;
1294 				++dcmds;
1295 				dtot += dma_len - off;
1296 				off = 0;
1297 			}
1298 		}
1299 	}
1300 	if (dtot == 0) {
1301 		/* Either the target has overrun our buffer,
1302 		   or the caller didn't provide a buffer. */
1303 		static char mesh_extra_buf[64];
1304 
1305 		dtot = sizeof(mesh_extra_buf);
1306 		dcmds->req_count = cpu_to_le16(dtot);
1307 		dcmds->phy_addr = cpu_to_le32(virt_to_phys(mesh_extra_buf));
1308 		dcmds->xfer_status = 0;
1309 		++dcmds;
1310 	}
1311 	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
1312 	dcmds[-1].command = cpu_to_le16(dma_cmd);
1313 	memset(dcmds, 0, sizeof(*dcmds));
1314 	dcmds->command = cpu_to_le16(DBDMA_STOP);
1315 	ms->dma_count = dtot;
1316 }
1317 
halt_dma(struct mesh_state * ms)1318 static void halt_dma(struct mesh_state *ms)
1319 {
1320 	volatile struct dbdma_regs __iomem *md = ms->dma;
1321 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1322 	struct scsi_cmnd *cmd = ms->current_req;
1323 	int t, nb;
1324 
1325 	if (!ms->tgts[ms->conn_tgt].data_goes_out) {
1326 		/* wait a little while until the fifo drains */
1327 		t = 50;
1328 		while (t > 0 && in_8(&mr->fifo_count) != 0
1329 		       && (in_le32(&md->status) & ACTIVE) != 0) {
1330 			--t;
1331 			udelay(1);
1332 		}
1333 	}
1334 	out_le32(&md->control, RUN << 16);	/* turn off RUN bit */
1335 	nb = (mr->count_hi << 8) + mr->count_lo;
1336 	dlog(ms, "halt_dma fc/count=%.6x",
1337 	     MKWORD(0, mr->fifo_count, 0, nb));
1338 	if (ms->tgts[ms->conn_tgt].data_goes_out)
1339 		nb += mr->fifo_count;
1340 	/* nb is the number of bytes not yet transferred
1341 	   to/from the target. */
1342 	ms->data_ptr -= nb;
1343 	dlog(ms, "data_ptr %x", ms->data_ptr);
1344 	if (ms->data_ptr < 0) {
1345 		printk(KERN_ERR "mesh: halt_dma: data_ptr=%d (nb=%d, ms=%p)\n",
1346 		       ms->data_ptr, nb, ms);
1347 		ms->data_ptr = 0;
1348 #ifdef MESH_DBG
1349 		dumplog(ms, ms->conn_tgt);
1350 		dumpslog(ms);
1351 #endif /* MESH_DBG */
1352 	} else if (cmd && scsi_bufflen(cmd) &&
1353 		   ms->data_ptr > scsi_bufflen(cmd)) {
1354 		printk(KERN_DEBUG "mesh: target %d overrun, "
1355 		       "data_ptr=%x total=%x goes_out=%d\n",
1356 		       ms->conn_tgt, ms->data_ptr, scsi_bufflen(cmd),
1357 		       ms->tgts[ms->conn_tgt].data_goes_out);
1358 	}
1359 	scsi_dma_unmap(cmd);
1360 	ms->dma_started = 0;
1361 }
1362 
phase_mismatch(struct mesh_state * ms)1363 static void phase_mismatch(struct mesh_state *ms)
1364 {
1365 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1366 	int phase;
1367 
1368 	dlog(ms, "phasemm ch/cl/seq/fc=%.8x",
1369 	     MKWORD(mr->count_hi, mr->count_lo, mr->sequence, mr->fifo_count));
1370 	phase = in_8(&mr->bus_status0) & BS0_PHASE;
1371 	if (ms->msgphase == msg_out_xxx && phase == BP_MSGOUT) {
1372 		/* output the last byte of the message, without ATN */
1373 		out_8(&mr->count_lo, 1);
1374 		out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
1375 		mesh_flush_io(mr);
1376 		udelay(1);
1377 		out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
1378 		ms->msgphase = msg_out_last;
1379 		return;
1380 	}
1381 
1382 	if (ms->msgphase == msg_in) {
1383 		get_msgin(ms);
1384 		if (ms->n_msgin)
1385 			handle_msgin(ms);
1386 	}
1387 
1388 	if (ms->dma_started)
1389 		halt_dma(ms);
1390 	if (mr->fifo_count) {
1391 		out_8(&mr->sequence, SEQ_FLUSHFIFO);
1392 		mesh_flush_io(mr);
1393 		udelay(1);
1394 	}
1395 
1396 	ms->msgphase = msg_none;
1397 	switch (phase) {
1398 	case BP_DATAIN:
1399 		ms->tgts[ms->conn_tgt].data_goes_out = 0;
1400 		ms->phase = dataing;
1401 		break;
1402 	case BP_DATAOUT:
1403 		ms->tgts[ms->conn_tgt].data_goes_out = 1;
1404 		ms->phase = dataing;
1405 		break;
1406 	case BP_COMMAND:
1407 		ms->phase = commanding;
1408 		break;
1409 	case BP_STATUS:
1410 		ms->phase = statusing;
1411 		break;
1412 	case BP_MSGIN:
1413 		ms->msgphase = msg_in;
1414 		ms->n_msgin = 0;
1415 		break;
1416 	case BP_MSGOUT:
1417 		ms->msgphase = msg_out;
1418 		if (ms->n_msgout == 0) {
1419 			if (ms->aborting) {
1420 				do_abort(ms);
1421 			} else {
1422 				if (ms->last_n_msgout == 0) {
1423 					printk(KERN_DEBUG
1424 					       "mesh: no msg to repeat\n");
1425 					ms->msgout[0] = NOP;
1426 					ms->last_n_msgout = 1;
1427 				}
1428 				ms->n_msgout = ms->last_n_msgout;
1429 			}
1430 		}
1431 		break;
1432 	default:
1433 		printk(KERN_DEBUG "mesh: unknown scsi phase %x\n", phase);
1434 		ms->stat = DID_ERROR;
1435 		mesh_done(ms, 1);
1436 		return;
1437 	}
1438 
1439 	start_phase(ms);
1440 }
1441 
cmd_complete(struct mesh_state * ms)1442 static void cmd_complete(struct mesh_state *ms)
1443 {
1444 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1445 	struct scsi_cmnd *cmd = ms->current_req;
1446 	struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
1447 	int seq, n, t;
1448 
1449 	dlog(ms, "cmd_complete fc=%x", mr->fifo_count);
1450 	seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
1451 	switch (ms->msgphase) {
1452 	case msg_out_xxx:
1453 		/* huh?  we expected a phase mismatch */
1454 		ms->n_msgin = 0;
1455 		ms->msgphase = msg_in;
1456 		/* fall through */
1457 
1458 	case msg_in:
1459 		/* should have some message bytes in fifo */
1460 		get_msgin(ms);
1461 		n = msgin_length(ms);
1462 		if (ms->n_msgin < n) {
1463 			out_8(&mr->count_lo, n - ms->n_msgin);
1464 			out_8(&mr->sequence, SEQ_MSGIN + seq);
1465 		} else {
1466 			ms->msgphase = msg_none;
1467 			handle_msgin(ms);
1468 			start_phase(ms);
1469 		}
1470 		break;
1471 
1472 	case msg_in_bad:
1473 		out_8(&mr->sequence, SEQ_FLUSHFIFO);
1474 		mesh_flush_io(mr);
1475 		udelay(1);
1476 		out_8(&mr->count_lo, 1);
1477 		out_8(&mr->sequence, SEQ_MSGIN + SEQ_ATN + use_active_neg);
1478 		break;
1479 
1480 	case msg_out:
1481 		/*
1482 		 * To get the right timing on ATN wrt ACK, we have
1483 		 * to get the MESH to drop ACK, wait until REQ gets
1484 		 * asserted, then drop ATN.  To do this we first
1485 		 * issue a SEQ_MSGOUT with ATN and wait for REQ,
1486 		 * then change the command to a SEQ_MSGOUT w/o ATN.
1487 		 * If we don't see REQ in a reasonable time, we
1488 		 * change the command to SEQ_MSGIN with ATN,
1489 		 * wait for the phase mismatch interrupt, then
1490 		 * issue the SEQ_MSGOUT without ATN.
1491 		 */
1492 		out_8(&mr->count_lo, 1);
1493 		out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg + SEQ_ATN);
1494 		t = 30;		/* wait up to 30us */
1495 		while ((in_8(&mr->bus_status0) & BS0_REQ) == 0 && --t >= 0)
1496 			udelay(1);
1497 		dlog(ms, "last_mbyte err/exc/fc/cl=%.8x",
1498 		     MKWORD(mr->error, mr->exception,
1499 			    mr->fifo_count, mr->count_lo));
1500 		if (in_8(&mr->interrupt) & (INT_ERROR | INT_EXCEPTION)) {
1501 			/* whoops, target didn't do what we expected */
1502 			ms->last_n_msgout = ms->n_msgout;
1503 			ms->n_msgout = 0;
1504 			if (in_8(&mr->interrupt) & INT_ERROR) {
1505 				printk(KERN_ERR "mesh: error %x in msg_out\n",
1506 				       in_8(&mr->error));
1507 				handle_error(ms);
1508 				return;
1509 			}
1510 			if (in_8(&mr->exception) != EXC_PHASEMM)
1511 				printk(KERN_ERR "mesh: exc %x in msg_out\n",
1512 				       in_8(&mr->exception));
1513 			else
1514 				printk(KERN_DEBUG "mesh: bs0=%x in msg_out\n",
1515 				       in_8(&mr->bus_status0));
1516 			handle_exception(ms);
1517 			return;
1518 		}
1519 		if (in_8(&mr->bus_status0) & BS0_REQ) {
1520 			out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
1521 			mesh_flush_io(mr);
1522 			udelay(1);
1523 			out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
1524 			ms->msgphase = msg_out_last;
1525 		} else {
1526 			out_8(&mr->sequence, SEQ_MSGIN + use_active_neg + SEQ_ATN);
1527 			ms->msgphase = msg_out_xxx;
1528 		}
1529 		break;
1530 
1531 	case msg_out_last:
1532 		ms->last_n_msgout = ms->n_msgout;
1533 		ms->n_msgout = 0;
1534 		ms->msgphase = ms->expect_reply? msg_in: msg_none;
1535 		start_phase(ms);
1536 		break;
1537 
1538 	case msg_none:
1539 		switch (ms->phase) {
1540 		case idle:
1541 			printk(KERN_ERR "mesh: interrupt in idle phase?\n");
1542 			dumpslog(ms);
1543 			return;
1544 		case selecting:
1545 			dlog(ms, "Selecting phase at command completion",0);
1546 			ms->msgout[0] = IDENTIFY(ALLOW_RESEL(ms->conn_tgt),
1547 						 (cmd? cmd->device->lun: 0));
1548 			ms->n_msgout = 1;
1549 			ms->expect_reply = 0;
1550 			if (ms->aborting) {
1551 				ms->msgout[0] = ABORT;
1552 				ms->n_msgout++;
1553 			} else if (tp->sdtr_state == do_sdtr) {
1554 				/* add SDTR message */
1555 				add_sdtr_msg(ms);
1556 				ms->expect_reply = 1;
1557 				tp->sdtr_state = sdtr_sent;
1558 			}
1559 			ms->msgphase = msg_out;
1560 			/*
1561 			 * We need to wait for REQ before dropping ATN.
1562 			 * We wait for at most 30us, then fall back to
1563 			 * a scheme where we issue a SEQ_COMMAND with ATN,
1564 			 * which will give us a phase mismatch interrupt
1565 			 * when REQ does come, and then we send the message.
1566 			 */
1567 			t = 230;		/* wait up to 230us */
1568 			while ((in_8(&mr->bus_status0) & BS0_REQ) == 0) {
1569 				if (--t < 0) {
1570 					dlog(ms, "impatient for req", ms->n_msgout);
1571 					ms->msgphase = msg_none;
1572 					break;
1573 				}
1574 				udelay(1);
1575 			}
1576 			break;
1577 		case dataing:
1578 			if (ms->dma_count != 0) {
1579 				start_phase(ms);
1580 				return;
1581 			}
1582 			/*
1583 			 * We can get a phase mismatch here if the target
1584 			 * changes to the status phase, even though we have
1585 			 * had a command complete interrupt.  Then, if we
1586 			 * issue the SEQ_STATUS command, we'll get a sequence
1587 			 * error interrupt.  Which isn't so bad except that
1588 			 * occasionally the mesh actually executes the
1589 			 * SEQ_STATUS *as well as* giving us the sequence
1590 			 * error and phase mismatch exception.
1591 			 */
1592 			out_8(&mr->sequence, 0);
1593 			out_8(&mr->interrupt,
1594 			      INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1595 			halt_dma(ms);
1596 			break;
1597 		case statusing:
1598 			if (cmd) {
1599 				cmd->SCp.Status = mr->fifo;
1600 				if (DEBUG_TARGET(cmd))
1601 					printk(KERN_DEBUG "mesh: status is %x\n",
1602 					       cmd->SCp.Status);
1603 			}
1604 			ms->msgphase = msg_in;
1605 			break;
1606 		case busfreeing:
1607 			mesh_done(ms, 1);
1608 			return;
1609 		case disconnecting:
1610 			ms->current_req = NULL;
1611 			ms->phase = idle;
1612 			mesh_start(ms);
1613 			return;
1614 		default:
1615 			break;
1616 		}
1617 		++ms->phase;
1618 		start_phase(ms);
1619 		break;
1620 	}
1621 }
1622 
1623 
1624 /*
1625  * Called by midlayer with host locked to queue a new
1626  * request
1627  */
mesh_queue_lck(struct scsi_cmnd * cmd,void (* done)(struct scsi_cmnd *))1628 static int mesh_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
1629 {
1630 	struct mesh_state *ms;
1631 
1632 	cmd->scsi_done = done;
1633 	cmd->host_scribble = NULL;
1634 
1635 	ms = (struct mesh_state *) cmd->device->host->hostdata;
1636 
1637 	if (ms->request_q == NULL)
1638 		ms->request_q = cmd;
1639 	else
1640 		ms->request_qtail->host_scribble = (void *) cmd;
1641 	ms->request_qtail = cmd;
1642 
1643 	if (ms->phase == idle)
1644 		mesh_start(ms);
1645 
1646 	return 0;
1647 }
1648 
DEF_SCSI_QCMD(mesh_queue)1649 static DEF_SCSI_QCMD(mesh_queue)
1650 
1651 /*
1652  * Called to handle interrupts, either call by the interrupt
1653  * handler (do_mesh_interrupt) or by other functions in
1654  * exceptional circumstances
1655  */
1656 static void mesh_interrupt(struct mesh_state *ms)
1657 {
1658 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1659 	int intr;
1660 
1661 #if 0
1662 	if (ALLOW_DEBUG(ms->conn_tgt))
1663 		printk(KERN_DEBUG "mesh_intr, bs0=%x int=%x exc=%x err=%x "
1664 		       "phase=%d msgphase=%d\n", mr->bus_status0,
1665 		       mr->interrupt, mr->exception, mr->error,
1666 		       ms->phase, ms->msgphase);
1667 #endif
1668 	while ((intr = in_8(&mr->interrupt)) != 0) {
1669 		dlog(ms, "interrupt intr/err/exc/seq=%.8x",
1670 		     MKWORD(intr, mr->error, mr->exception, mr->sequence));
1671 		if (intr & INT_ERROR) {
1672 			handle_error(ms);
1673 		} else if (intr & INT_EXCEPTION) {
1674 			handle_exception(ms);
1675 		} else if (intr & INT_CMDDONE) {
1676 			out_8(&mr->interrupt, INT_CMDDONE);
1677 			cmd_complete(ms);
1678 		}
1679 	}
1680 }
1681 
1682 /* Todo: here we can at least try to remove the command from the
1683  * queue if it isn't connected yet, and for pending command, assert
1684  * ATN until the bus gets freed.
1685  */
mesh_abort(struct scsi_cmnd * cmd)1686 static int mesh_abort(struct scsi_cmnd *cmd)
1687 {
1688 	struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
1689 
1690 	printk(KERN_DEBUG "mesh_abort(%p)\n", cmd);
1691 	mesh_dump_regs(ms);
1692 	dumplog(ms, cmd->device->id);
1693 	dumpslog(ms);
1694 	return FAILED;
1695 }
1696 
1697 /*
1698  * Called by the midlayer with the lock held to reset the
1699  * SCSI host and bus.
1700  * The midlayer will wait for devices to come back, we don't need
1701  * to do that ourselves
1702  */
mesh_host_reset(struct scsi_cmnd * cmd)1703 static int mesh_host_reset(struct scsi_cmnd *cmd)
1704 {
1705 	struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
1706 	volatile struct mesh_regs __iomem *mr = ms->mesh;
1707 	volatile struct dbdma_regs __iomem *md = ms->dma;
1708 	unsigned long flags;
1709 
1710 	printk(KERN_DEBUG "mesh_host_reset\n");
1711 
1712 	spin_lock_irqsave(ms->host->host_lock, flags);
1713 
1714 	/* Reset the controller & dbdma channel */
1715 	out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16);	/* stop dma */
1716 	out_8(&mr->exception, 0xff);	/* clear all exception bits */
1717 	out_8(&mr->error, 0xff);	/* clear all error bits */
1718 	out_8(&mr->sequence, SEQ_RESETMESH);
1719        	mesh_flush_io(mr);
1720 	udelay(1);
1721 	out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1722 	out_8(&mr->source_id, ms->host->this_id);
1723 	out_8(&mr->sel_timeout, 25);	/* 250ms */
1724 	out_8(&mr->sync_params, ASYNC_PARAMS);
1725 
1726 	/* Reset the bus */
1727 	out_8(&mr->bus_status1, BS1_RST);	/* assert RST */
1728        	mesh_flush_io(mr);
1729 	udelay(30);			/* leave it on for >= 25us */
1730 	out_8(&mr->bus_status1, 0);	/* negate RST */
1731 
1732 	/* Complete pending commands */
1733 	handle_reset(ms);
1734 
1735 	spin_unlock_irqrestore(ms->host->host_lock, flags);
1736 	return SUCCESS;
1737 }
1738 
set_mesh_power(struct mesh_state * ms,int state)1739 static void set_mesh_power(struct mesh_state *ms, int state)
1740 {
1741 	if (!machine_is(powermac))
1742 		return;
1743 	if (state) {
1744 		pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 1);
1745 		msleep(200);
1746 	} else {
1747 		pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 0);
1748 		msleep(10);
1749 	}
1750 }
1751 
1752 
1753 #ifdef CONFIG_PM
mesh_suspend(struct macio_dev * mdev,pm_message_t mesg)1754 static int mesh_suspend(struct macio_dev *mdev, pm_message_t mesg)
1755 {
1756 	struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1757 	unsigned long flags;
1758 
1759 	switch (mesg.event) {
1760 	case PM_EVENT_SUSPEND:
1761 	case PM_EVENT_HIBERNATE:
1762 	case PM_EVENT_FREEZE:
1763 		break;
1764 	default:
1765 		return 0;
1766 	}
1767 	if (ms->phase == sleeping)
1768 		return 0;
1769 
1770 	scsi_block_requests(ms->host);
1771 	spin_lock_irqsave(ms->host->host_lock, flags);
1772 	while(ms->phase != idle) {
1773 		spin_unlock_irqrestore(ms->host->host_lock, flags);
1774 		msleep(10);
1775 		spin_lock_irqsave(ms->host->host_lock, flags);
1776 	}
1777 	ms->phase = sleeping;
1778 	spin_unlock_irqrestore(ms->host->host_lock, flags);
1779 	disable_irq(ms->meshintr);
1780 	set_mesh_power(ms, 0);
1781 
1782 	return 0;
1783 }
1784 
mesh_resume(struct macio_dev * mdev)1785 static int mesh_resume(struct macio_dev *mdev)
1786 {
1787 	struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1788 	unsigned long flags;
1789 
1790 	if (ms->phase != sleeping)
1791 		return 0;
1792 
1793 	set_mesh_power(ms, 1);
1794 	mesh_init(ms);
1795 	spin_lock_irqsave(ms->host->host_lock, flags);
1796 	mesh_start(ms);
1797 	spin_unlock_irqrestore(ms->host->host_lock, flags);
1798 	enable_irq(ms->meshintr);
1799 	scsi_unblock_requests(ms->host);
1800 
1801 	return 0;
1802 }
1803 
1804 #endif /* CONFIG_PM */
1805 
1806 /*
1807  * If we leave drives set for synchronous transfers (especially
1808  * CDROMs), and reboot to MacOS, it gets confused, poor thing.
1809  * So, on reboot we reset the SCSI bus.
1810  */
mesh_shutdown(struct macio_dev * mdev)1811 static int mesh_shutdown(struct macio_dev *mdev)
1812 {
1813 	struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1814 	volatile struct mesh_regs __iomem *mr;
1815 	unsigned long flags;
1816 
1817        	printk(KERN_INFO "resetting MESH scsi bus(es)\n");
1818 	spin_lock_irqsave(ms->host->host_lock, flags);
1819        	mr = ms->mesh;
1820 	out_8(&mr->intr_mask, 0);
1821 	out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1822 	out_8(&mr->bus_status1, BS1_RST);
1823 	mesh_flush_io(mr);
1824 	udelay(30);
1825 	out_8(&mr->bus_status1, 0);
1826 	spin_unlock_irqrestore(ms->host->host_lock, flags);
1827 
1828 	return 0;
1829 }
1830 
1831 static struct scsi_host_template mesh_template = {
1832 	.proc_name			= "mesh",
1833 	.name				= "MESH",
1834 	.queuecommand			= mesh_queue,
1835 	.eh_abort_handler		= mesh_abort,
1836 	.eh_host_reset_handler		= mesh_host_reset,
1837 	.can_queue			= 20,
1838 	.this_id			= 7,
1839 	.sg_tablesize			= SG_ALL,
1840 	.cmd_per_lun			= 2,
1841 	.use_clustering			= DISABLE_CLUSTERING,
1842 };
1843 
mesh_probe(struct macio_dev * mdev,const struct of_device_id * match)1844 static int mesh_probe(struct macio_dev *mdev, const struct of_device_id *match)
1845 {
1846 	struct device_node *mesh = macio_get_of_node(mdev);
1847 	struct pci_dev* pdev = macio_get_pci_dev(mdev);
1848 	int tgt, minper;
1849 	const int *cfp;
1850 	struct mesh_state *ms;
1851 	struct Scsi_Host *mesh_host;
1852 	void *dma_cmd_space;
1853 	dma_addr_t dma_cmd_bus;
1854 
1855 	switch (mdev->bus->chip->type) {
1856 	case macio_heathrow:
1857 	case macio_gatwick:
1858 	case macio_paddington:
1859 		use_active_neg = 0;
1860 		break;
1861 	default:
1862 		use_active_neg = SEQ_ACTIVE_NEG;
1863 	}
1864 
1865 	if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
1866        		printk(KERN_ERR "mesh: expected 2 addrs and 2 intrs"
1867 	       	       " (got %d,%d)\n", macio_resource_count(mdev),
1868 		       macio_irq_count(mdev));
1869 		return -ENODEV;
1870 	}
1871 
1872 	if (macio_request_resources(mdev, "mesh") != 0) {
1873        		printk(KERN_ERR "mesh: unable to request memory resources");
1874 		return -EBUSY;
1875 	}
1876        	mesh_host = scsi_host_alloc(&mesh_template, sizeof(struct mesh_state));
1877 	if (mesh_host == NULL) {
1878 		printk(KERN_ERR "mesh: couldn't register host");
1879 		goto out_release;
1880 	}
1881 
1882 	/* Old junk for root discovery, that will die ultimately */
1883 #if !defined(MODULE)
1884        	note_scsi_host(mesh, mesh_host);
1885 #endif
1886 
1887 	mesh_host->base = macio_resource_start(mdev, 0);
1888 	mesh_host->irq = macio_irq(mdev, 0);
1889        	ms = (struct mesh_state *) mesh_host->hostdata;
1890 	macio_set_drvdata(mdev, ms);
1891 	ms->host = mesh_host;
1892 	ms->mdev = mdev;
1893 	ms->pdev = pdev;
1894 
1895 	ms->mesh = ioremap(macio_resource_start(mdev, 0), 0x1000);
1896 	if (ms->mesh == NULL) {
1897 		printk(KERN_ERR "mesh: can't map registers\n");
1898 		goto out_free;
1899 	}
1900 	ms->dma = ioremap(macio_resource_start(mdev, 1), 0x1000);
1901 	if (ms->dma == NULL) {
1902 		printk(KERN_ERR "mesh: can't map registers\n");
1903 		iounmap(ms->mesh);
1904 		goto out_free;
1905 	}
1906 
1907        	ms->meshintr = macio_irq(mdev, 0);
1908        	ms->dmaintr = macio_irq(mdev, 1);
1909 
1910        	/* Space for dma command list: +1 for stop command,
1911        	 * +1 to allow for aligning.
1912 	 */
1913 	ms->dma_cmd_size = (mesh_host->sg_tablesize + 2) * sizeof(struct dbdma_cmd);
1914 
1915 	/* We use the PCI APIs for now until the generic one gets fixed
1916 	 * enough or until we get some macio-specific versions
1917 	 */
1918 	dma_cmd_space = pci_zalloc_consistent(macio_get_pci_dev(mdev),
1919 					      ms->dma_cmd_size, &dma_cmd_bus);
1920 	if (dma_cmd_space == NULL) {
1921 		printk(KERN_ERR "mesh: can't allocate DMA table\n");
1922 		goto out_unmap;
1923 	}
1924 
1925 	ms->dma_cmds = (struct dbdma_cmd *) DBDMA_ALIGN(dma_cmd_space);
1926        	ms->dma_cmd_space = dma_cmd_space;
1927 	ms->dma_cmd_bus = dma_cmd_bus + ((unsigned long)ms->dma_cmds)
1928 		- (unsigned long)dma_cmd_space;
1929 	ms->current_req = NULL;
1930        	for (tgt = 0; tgt < 8; ++tgt) {
1931 	       	ms->tgts[tgt].sdtr_state = do_sdtr;
1932 	       	ms->tgts[tgt].sync_params = ASYNC_PARAMS;
1933 	       	ms->tgts[tgt].current_req = NULL;
1934        	}
1935 
1936 	if ((cfp = of_get_property(mesh, "clock-frequency", NULL)))
1937        		ms->clk_freq = *cfp;
1938 	else {
1939        		printk(KERN_INFO "mesh: assuming 50MHz clock frequency\n");
1940 	       	ms->clk_freq = 50000000;
1941        	}
1942 
1943        	/* The maximum sync rate is clock / 5; increase
1944        	 * mesh_sync_period if necessary.
1945 	 */
1946 	minper = 1000000000 / (ms->clk_freq / 5); /* ns */
1947 	if (mesh_sync_period < minper)
1948 		mesh_sync_period = minper;
1949 
1950 	/* Power up the chip */
1951 	set_mesh_power(ms, 1);
1952 
1953 	/* Set it up */
1954        	mesh_init(ms);
1955 
1956 	/* Request interrupt */
1957        	if (request_irq(ms->meshintr, do_mesh_interrupt, 0, "MESH", ms)) {
1958 	       	printk(KERN_ERR "MESH: can't get irq %d\n", ms->meshintr);
1959 		goto out_shutdown;
1960 	}
1961 
1962 	/* Add scsi host & scan */
1963 	if (scsi_add_host(mesh_host, &mdev->ofdev.dev))
1964 		goto out_release_irq;
1965 	scsi_scan_host(mesh_host);
1966 
1967 	return 0;
1968 
1969  out_release_irq:
1970 	free_irq(ms->meshintr, ms);
1971  out_shutdown:
1972 	/* shutdown & reset bus in case of error or macos can be confused
1973 	 * at reboot if the bus was set to synchronous mode already
1974 	 */
1975 	mesh_shutdown(mdev);
1976 	set_mesh_power(ms, 0);
1977 	pci_free_consistent(macio_get_pci_dev(mdev), ms->dma_cmd_size,
1978 			    ms->dma_cmd_space, ms->dma_cmd_bus);
1979  out_unmap:
1980 	iounmap(ms->dma);
1981 	iounmap(ms->mesh);
1982  out_free:
1983 	scsi_host_put(mesh_host);
1984  out_release:
1985 	macio_release_resources(mdev);
1986 
1987 	return -ENODEV;
1988 }
1989 
mesh_remove(struct macio_dev * mdev)1990 static int mesh_remove(struct macio_dev *mdev)
1991 {
1992 	struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1993 	struct Scsi_Host *mesh_host = ms->host;
1994 
1995 	scsi_remove_host(mesh_host);
1996 
1997 	free_irq(ms->meshintr, ms);
1998 
1999 	/* Reset scsi bus */
2000 	mesh_shutdown(mdev);
2001 
2002 	/* Shut down chip & termination */
2003 	set_mesh_power(ms, 0);
2004 
2005 	/* Unmap registers & dma controller */
2006 	iounmap(ms->mesh);
2007        	iounmap(ms->dma);
2008 
2009 	/* Free DMA commands memory */
2010 	pci_free_consistent(macio_get_pci_dev(mdev), ms->dma_cmd_size,
2011 			    ms->dma_cmd_space, ms->dma_cmd_bus);
2012 
2013 	/* Release memory resources */
2014 	macio_release_resources(mdev);
2015 
2016 	scsi_host_put(mesh_host);
2017 
2018 	return 0;
2019 }
2020 
2021 
2022 static struct of_device_id mesh_match[] =
2023 {
2024 	{
2025 	.name 		= "mesh",
2026 	},
2027 	{
2028 	.type		= "scsi",
2029 	.compatible	= "chrp,mesh0"
2030 	},
2031 	{},
2032 };
2033 MODULE_DEVICE_TABLE (of, mesh_match);
2034 
2035 static struct macio_driver mesh_driver =
2036 {
2037 	.driver = {
2038 		.name 		= "mesh",
2039 		.owner		= THIS_MODULE,
2040 		.of_match_table	= mesh_match,
2041 	},
2042 	.probe		= mesh_probe,
2043 	.remove		= mesh_remove,
2044 	.shutdown	= mesh_shutdown,
2045 #ifdef CONFIG_PM
2046 	.suspend	= mesh_suspend,
2047 	.resume		= mesh_resume,
2048 #endif
2049 };
2050 
2051 
init_mesh(void)2052 static int __init init_mesh(void)
2053 {
2054 
2055 	/* Calculate sync rate from module parameters */
2056 	if (sync_rate > 10)
2057 		sync_rate = 10;
2058 	if (sync_rate > 0) {
2059 		printk(KERN_INFO "mesh: configured for synchronous %d MB/s\n", sync_rate);
2060 		mesh_sync_period = 1000 / sync_rate;	/* ns */
2061 		mesh_sync_offset = 15;
2062 	} else
2063 		printk(KERN_INFO "mesh: configured for asynchronous\n");
2064 
2065 	return macio_register_driver(&mesh_driver);
2066 }
2067 
exit_mesh(void)2068 static void __exit exit_mesh(void)
2069 {
2070 	return macio_unregister_driver(&mesh_driver);
2071 }
2072 
2073 module_init(init_mesh);
2074 module_exit(exit_mesh);
2075