[ARM] omap: i2c: use short connection ids
[linux-2.6] / drivers / scsi / mesh.c
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/slab.h>
27 #include <linux/blkdev.h>
28 #include <linux/proc_fs.h>
29 #include <linux/stat.h>
30 #include <linux/interrupt.h>
31 #include <linux/reboot.h>
32 #include <linux/spinlock.h>
33 #include <asm/dbdma.h>
34 #include <asm/io.h>
35 #include <asm/pgtable.h>
36 #include <asm/prom.h>
37 #include <asm/system.h>
38 #include <asm/irq.h>
39 #include <asm/hydra.h>
40 #include <asm/processor.h>
41 #include <asm/machdep.h>
42 #include <asm/pmac_feature.h>
43 #include <asm/pci-bridge.h>
44 #include <asm/macio.h>
45
46 #include <scsi/scsi.h>
47 #include <scsi/scsi_cmnd.h>
48 #include <scsi/scsi_device.h>
49 #include <scsi/scsi_host.h>
50
51 #include "mesh.h"
52
53 #if 1
54 #undef KERN_DEBUG
55 #define KERN_DEBUG KERN_WARNING
56 #endif
57
58 MODULE_AUTHOR("Paul Mackerras (paulus@samba.org)");
59 MODULE_DESCRIPTION("PowerMac MESH SCSI driver");
60 MODULE_LICENSE("GPL");
61
62 static int sync_rate = CONFIG_SCSI_MESH_SYNC_RATE;
63 static int sync_targets = 0xff;
64 static int resel_targets = 0xff;
65 static int debug_targets = 0;   /* print debug for these targets */
66 static int init_reset_delay = CONFIG_SCSI_MESH_RESET_DELAY_MS;
67
68 module_param(sync_rate, int, 0);
69 MODULE_PARM_DESC(sync_rate, "Synchronous rate (0..10, 0=async)");
70 module_param(sync_targets, int, 0);
71 MODULE_PARM_DESC(sync_targets, "Bitmask of targets allowed to set synchronous");
72 module_param(resel_targets, int, 0);
73 MODULE_PARM_DESC(resel_targets, "Bitmask of targets allowed to set disconnect");
74 module_param(debug_targets, int, 0644);
75 MODULE_PARM_DESC(debug_targets, "Bitmask of debugged targets");
76 module_param(init_reset_delay, int, 0);
77 MODULE_PARM_DESC(init_reset_delay, "Initial bus reset delay (0=no reset)");
78
79 static int mesh_sync_period = 100;
80 static int mesh_sync_offset = 0;
81 static unsigned char use_active_neg = 0;  /* bit mask for SEQ_ACTIVE_NEG if used */
82
83 #define ALLOW_SYNC(tgt)         ((sync_targets >> (tgt)) & 1)
84 #define ALLOW_RESEL(tgt)        ((resel_targets >> (tgt)) & 1)
85 #define ALLOW_DEBUG(tgt)        ((debug_targets >> (tgt)) & 1)
86 #define DEBUG_TARGET(cmd)       ((cmd) && ALLOW_DEBUG((cmd)->device->id))
87
88 #undef MESH_DBG
89 #define N_DBG_LOG       50
90 #define N_DBG_SLOG      20
91 #define NUM_DBG_EVENTS  13
92 #undef  DBG_USE_TB              /* bombs on 601 */
93
94 struct dbglog {
95         char    *fmt;
96         u32     tb;
97         u8      phase;
98         u8      bs0;
99         u8      bs1;
100         u8      tgt;
101         int     d;
102 };
103
104 enum mesh_phase {
105         idle,
106         arbitrating,
107         selecting,
108         commanding,
109         dataing,
110         statusing,
111         busfreeing,
112         disconnecting,
113         reselecting,
114         sleeping
115 };
116
117 enum msg_phase {
118         msg_none,
119         msg_out,
120         msg_out_xxx,
121         msg_out_last,
122         msg_in,
123         msg_in_bad,
124 };
125
126 enum sdtr_phase {
127         do_sdtr,
128         sdtr_sent,
129         sdtr_done
130 };
131
132 struct mesh_target {
133         enum sdtr_phase sdtr_state;
134         int     sync_params;
135         int     data_goes_out;          /* guess as to data direction */
136         struct scsi_cmnd *current_req;
137         u32     saved_ptr;
138 #ifdef MESH_DBG
139         int     log_ix;
140         int     n_log;
141         struct dbglog log[N_DBG_LOG];
142 #endif
143 };
144
145 struct mesh_state {
146         volatile struct mesh_regs __iomem *mesh;
147         int     meshintr;
148         volatile struct dbdma_regs __iomem *dma;
149         int     dmaintr;
150         struct  Scsi_Host *host;
151         struct  mesh_state *next;
152         struct scsi_cmnd *request_q;
153         struct scsi_cmnd *request_qtail;
154         enum mesh_phase phase;          /* what we're currently trying to do */
155         enum msg_phase msgphase;
156         int     conn_tgt;               /* target we're connected to */
157         struct scsi_cmnd *current_req;          /* req we're currently working on */
158         int     data_ptr;
159         int     dma_started;
160         int     dma_count;
161         int     stat;
162         int     aborting;
163         int     expect_reply;
164         int     n_msgin;
165         u8      msgin[16];
166         int     n_msgout;
167         int     last_n_msgout;
168         u8      msgout[16];
169         struct dbdma_cmd *dma_cmds;     /* space for dbdma commands, aligned */
170         dma_addr_t dma_cmd_bus;
171         void    *dma_cmd_space;
172         int     dma_cmd_size;
173         int     clk_freq;
174         struct mesh_target tgts[8];
175         struct macio_dev *mdev;
176         struct pci_dev* pdev;
177 #ifdef MESH_DBG
178         int     log_ix;
179         int     n_log;
180         struct dbglog log[N_DBG_SLOG];
181 #endif
182 };
183
184 /*
185  * Driver is too messy, we need a few prototypes...
186  */
187 static void mesh_done(struct mesh_state *ms, int start_next);
188 static void mesh_interrupt(struct mesh_state *ms);
189 static void cmd_complete(struct mesh_state *ms);
190 static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd);
191 static void halt_dma(struct mesh_state *ms);
192 static void phase_mismatch(struct mesh_state *ms);
193
194
195 /*
196  * Some debugging & logging routines
197  */
198
199 #ifdef MESH_DBG
200
201 static inline u32 readtb(void)
202 {
203         u32 tb;
204
205 #ifdef DBG_USE_TB
206         /* Beware: if you enable this, it will crash on 601s. */
207         asm ("mftb %0" : "=r" (tb) : );
208 #else
209         tb = 0;
210 #endif
211         return tb;
212 }
213
214 static void dlog(struct mesh_state *ms, char *fmt, int a)
215 {
216         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
217         struct dbglog *tlp, *slp;
218
219         tlp = &tp->log[tp->log_ix];
220         slp = &ms->log[ms->log_ix];
221         tlp->fmt = fmt;
222         tlp->tb = readtb();
223         tlp->phase = (ms->msgphase << 4) + ms->phase;
224         tlp->bs0 = ms->mesh->bus_status0;
225         tlp->bs1 = ms->mesh->bus_status1;
226         tlp->tgt = ms->conn_tgt;
227         tlp->d = a;
228         *slp = *tlp;
229         if (++tp->log_ix >= N_DBG_LOG)
230                 tp->log_ix = 0;
231         if (tp->n_log < N_DBG_LOG)
232                 ++tp->n_log;
233         if (++ms->log_ix >= N_DBG_SLOG)
234                 ms->log_ix = 0;
235         if (ms->n_log < N_DBG_SLOG)
236                 ++ms->n_log;
237 }
238
239 static void dumplog(struct mesh_state *ms, int t)
240 {
241         struct mesh_target *tp = &ms->tgts[t];
242         struct dbglog *lp;
243         int i;
244
245         if (tp->n_log == 0)
246                 return;
247         i = tp->log_ix - tp->n_log;
248         if (i < 0)
249                 i += N_DBG_LOG;
250         tp->n_log = 0;
251         do {
252                 lp = &tp->log[i];
253                 printk(KERN_DEBUG "mesh log %d: bs=%.2x%.2x ph=%.2x ",
254                        t, lp->bs1, lp->bs0, lp->phase);
255 #ifdef DBG_USE_TB
256                 printk("tb=%10u ", lp->tb);
257 #endif
258                 printk(lp->fmt, lp->d);
259                 printk("\n");
260                 if (++i >= N_DBG_LOG)
261                         i = 0;
262         } while (i != tp->log_ix);
263 }
264
265 static void dumpslog(struct mesh_state *ms)
266 {
267         struct dbglog *lp;
268         int i;
269
270         if (ms->n_log == 0)
271                 return;
272         i = ms->log_ix - ms->n_log;
273         if (i < 0)
274                 i += N_DBG_SLOG;
275         ms->n_log = 0;
276         do {
277                 lp = &ms->log[i];
278                 printk(KERN_DEBUG "mesh log: bs=%.2x%.2x ph=%.2x t%d ",
279                        lp->bs1, lp->bs0, lp->phase, lp->tgt);
280 #ifdef DBG_USE_TB
281                 printk("tb=%10u ", lp->tb);
282 #endif
283                 printk(lp->fmt, lp->d);
284                 printk("\n");
285                 if (++i >= N_DBG_SLOG)
286                         i = 0;
287         } while (i != ms->log_ix);
288 }
289
290 #else
291
292 static inline void dlog(struct mesh_state *ms, char *fmt, int a)
293 {}
294 static inline void dumplog(struct mesh_state *ms, int tgt)
295 {}
296 static inline void dumpslog(struct mesh_state *ms)
297 {}
298
299 #endif /* MESH_DBG */
300
301 #define MKWORD(a, b, c, d)      (((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
302
303 static void
304 mesh_dump_regs(struct mesh_state *ms)
305 {
306         volatile struct mesh_regs __iomem *mr = ms->mesh;
307         volatile struct dbdma_regs __iomem *md = ms->dma;
308         int t;
309         struct mesh_target *tp;
310
311         printk(KERN_DEBUG "mesh: state at %p, regs at %p, dma at %p\n",
312                ms, mr, md);
313         printk(KERN_DEBUG "    ct=%4x seq=%2x bs=%4x fc=%2x "
314                "exc=%2x err=%2x im=%2x int=%2x sp=%2x\n",
315                (mr->count_hi << 8) + mr->count_lo, mr->sequence,
316                (mr->bus_status1 << 8) + mr->bus_status0, mr->fifo_count,
317                mr->exception, mr->error, mr->intr_mask, mr->interrupt,
318                mr->sync_params);
319         while(in_8(&mr->fifo_count))
320                 printk(KERN_DEBUG " fifo data=%.2x\n",in_8(&mr->fifo));
321         printk(KERN_DEBUG "    dma stat=%x cmdptr=%x\n",
322                in_le32(&md->status), in_le32(&md->cmdptr));
323         printk(KERN_DEBUG "    phase=%d msgphase=%d conn_tgt=%d data_ptr=%d\n",
324                ms->phase, ms->msgphase, ms->conn_tgt, ms->data_ptr);
325         printk(KERN_DEBUG "    dma_st=%d dma_ct=%d n_msgout=%d\n",
326                ms->dma_started, ms->dma_count, ms->n_msgout);
327         for (t = 0; t < 8; ++t) {
328                 tp = &ms->tgts[t];
329                 if (tp->current_req == NULL)
330                         continue;
331                 printk(KERN_DEBUG "    target %d: req=%p goes_out=%d saved_ptr=%d\n",
332                        t, tp->current_req, tp->data_goes_out, tp->saved_ptr);
333         }
334 }
335
336
337 /*
338  * Flush write buffers on the bus path to the mesh
339  */
340 static inline void mesh_flush_io(volatile struct mesh_regs __iomem *mr)
341 {
342         (void)in_8(&mr->mesh_id);
343 }
344
345
346 /*
347  * Complete a SCSI command
348  */
349 static void mesh_completed(struct mesh_state *ms, struct scsi_cmnd *cmd)
350 {
351         (*cmd->scsi_done)(cmd);
352 }
353
354
355 /* Called with  meshinterrupt disabled, initialize the chipset
356  * and eventually do the initial bus reset. The lock must not be
357  * held since we can schedule.
358  */
359 static void mesh_init(struct mesh_state *ms)
360 {
361         volatile struct mesh_regs __iomem *mr = ms->mesh;
362         volatile struct dbdma_regs __iomem *md = ms->dma;
363
364         mesh_flush_io(mr);
365         udelay(100);
366
367         /* Reset controller */
368         out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16);   /* stop dma */
369         out_8(&mr->exception, 0xff);    /* clear all exception bits */
370         out_8(&mr->error, 0xff);        /* clear all error bits */
371         out_8(&mr->sequence, SEQ_RESETMESH);
372         mesh_flush_io(mr);
373         udelay(10);
374         out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
375         out_8(&mr->source_id, ms->host->this_id);
376         out_8(&mr->sel_timeout, 25);    /* 250ms */
377         out_8(&mr->sync_params, ASYNC_PARAMS);
378
379         if (init_reset_delay) {
380                 printk(KERN_INFO "mesh: performing initial bus reset...\n");
381                 
382                 /* Reset bus */
383                 out_8(&mr->bus_status1, BS1_RST);       /* assert RST */
384                 mesh_flush_io(mr);
385                 udelay(30);                     /* leave it on for >= 25us */
386                 out_8(&mr->bus_status1, 0);     /* negate RST */
387                 mesh_flush_io(mr);
388
389                 /* Wait for bus to come back */
390                 msleep(init_reset_delay);
391         }
392         
393         /* Reconfigure controller */
394         out_8(&mr->interrupt, 0xff);    /* clear all interrupt bits */
395         out_8(&mr->sequence, SEQ_FLUSHFIFO);
396         mesh_flush_io(mr);
397         udelay(1);
398         out_8(&mr->sync_params, ASYNC_PARAMS);
399         out_8(&mr->sequence, SEQ_ENBRESEL);
400
401         ms->phase = idle;
402         ms->msgphase = msg_none;
403 }
404
405
406 static void mesh_start_cmd(struct mesh_state *ms, struct scsi_cmnd *cmd)
407 {
408         volatile struct mesh_regs __iomem *mr = ms->mesh;
409         int t, id;
410
411         id = cmd->device->id;
412         ms->current_req = cmd;
413         ms->tgts[id].data_goes_out = cmd->sc_data_direction == DMA_TO_DEVICE;
414         ms->tgts[id].current_req = cmd;
415
416 #if 1
417         if (DEBUG_TARGET(cmd)) {
418                 int i;
419                 printk(KERN_DEBUG "mesh_start: %p ser=%lu tgt=%d cmd=",
420                        cmd, cmd->serial_number, id);
421                 for (i = 0; i < cmd->cmd_len; ++i)
422                         printk(" %x", cmd->cmnd[i]);
423                 printk(" use_sg=%d buffer=%p bufflen=%u\n",
424                        scsi_sg_count(cmd), scsi_sglist(cmd), scsi_bufflen(cmd));
425         }
426 #endif
427         if (ms->dma_started)
428                 panic("mesh: double DMA start !\n");
429
430         ms->phase = arbitrating;
431         ms->msgphase = msg_none;
432         ms->data_ptr = 0;
433         ms->dma_started = 0;
434         ms->n_msgout = 0;
435         ms->last_n_msgout = 0;
436         ms->expect_reply = 0;
437         ms->conn_tgt = id;
438         ms->tgts[id].saved_ptr = 0;
439         ms->stat = DID_OK;
440         ms->aborting = 0;
441 #ifdef MESH_DBG
442         ms->tgts[id].n_log = 0;
443         dlog(ms, "start cmd=%x", (int) cmd);
444 #endif
445
446         /* Off we go */
447         dlog(ms, "about to arb, intr/exc/err/fc=%.8x",
448              MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
449         out_8(&mr->interrupt, INT_CMDDONE);
450         out_8(&mr->sequence, SEQ_ENBRESEL);
451         mesh_flush_io(mr);
452         udelay(1);
453
454         if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
455                 /*
456                  * Some other device has the bus or is arbitrating for it -
457                  * probably a target which is about to reselect us.
458                  */
459                 dlog(ms, "busy b4 arb, intr/exc/err/fc=%.8x",
460                      MKWORD(mr->interrupt, mr->exception,
461                             mr->error, mr->fifo_count));
462                 for (t = 100; t > 0; --t) {
463                         if ((in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) == 0)
464                                 break;
465                         if (in_8(&mr->interrupt) != 0) {
466                                 dlog(ms, "intr b4 arb, intr/exc/err/fc=%.8x",
467                                      MKWORD(mr->interrupt, mr->exception,
468                                             mr->error, mr->fifo_count));
469                                 mesh_interrupt(ms);
470                                 if (ms->phase != arbitrating)
471                                         return;
472                         }
473                         udelay(1);
474                 }
475                 if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
476                         /* XXX should try again in a little while */
477                         ms->stat = DID_BUS_BUSY;
478                         ms->phase = idle;
479                         mesh_done(ms, 0);
480                         return;
481                 }
482         }
483
484         /*
485          * Apparently the mesh has a bug where it will assert both its
486          * own bit and the target's bit on the bus during arbitration.
487          */
488         out_8(&mr->dest_id, mr->source_id);
489
490         /*
491          * There appears to be a race with reselection sometimes,
492          * where a target reselects us just as we issue the
493          * arbitrate command.  It seems that then the arbitrate
494          * command just hangs waiting for the bus to be free
495          * without giving us a reselection exception.
496          * The only way I have found to get it to respond correctly
497          * is this: disable reselection before issuing the arbitrate
498          * command, then after issuing it, if it looks like a target
499          * is trying to reselect us, reset the mesh and then enable
500          * reselection.
501          */
502         out_8(&mr->sequence, SEQ_DISRESEL);
503         if (in_8(&mr->interrupt) != 0) {
504                 dlog(ms, "intr after disresel, intr/exc/err/fc=%.8x",
505                      MKWORD(mr->interrupt, mr->exception,
506                             mr->error, mr->fifo_count));
507                 mesh_interrupt(ms);
508                 if (ms->phase != arbitrating)
509                         return;
510                 dlog(ms, "after intr after disresel, intr/exc/err/fc=%.8x",
511                      MKWORD(mr->interrupt, mr->exception,
512                             mr->error, mr->fifo_count));
513         }
514
515         out_8(&mr->sequence, SEQ_ARBITRATE);
516
517         for (t = 230; t > 0; --t) {
518                 if (in_8(&mr->interrupt) != 0)
519                         break;
520                 udelay(1);
521         }
522         dlog(ms, "after arb, intr/exc/err/fc=%.8x",
523              MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
524         if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
525             && (in_8(&mr->bus_status0) & BS0_IO)) {
526                 /* looks like a reselection - try resetting the mesh */
527                 dlog(ms, "resel? after arb, intr/exc/err/fc=%.8x",
528                      MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
529                 out_8(&mr->sequence, SEQ_RESETMESH);
530                 mesh_flush_io(mr);
531                 udelay(10);
532                 out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
533                 out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
534                 out_8(&mr->sequence, SEQ_ENBRESEL);
535                 mesh_flush_io(mr);
536                 for (t = 10; t > 0 && in_8(&mr->interrupt) == 0; --t)
537                         udelay(1);
538                 dlog(ms, "tried reset after arb, intr/exc/err/fc=%.8x",
539                      MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
540 #ifndef MESH_MULTIPLE_HOSTS
541                 if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
542                     && (in_8(&mr->bus_status0) & BS0_IO)) {
543                         printk(KERN_ERR "mesh: controller not responding"
544                                " to reselection!\n");
545                         /*
546                          * If this is a target reselecting us, and the
547                          * mesh isn't responding, the higher levels of
548                          * the scsi code will eventually time out and
549                          * reset the bus.
550                          */
551                 }
552 #endif
553         }
554 }
555
556 /*
557  * Start the next command for a MESH.
558  * Should be called with interrupts disabled.
559  */
560 static void mesh_start(struct mesh_state *ms)
561 {
562         struct scsi_cmnd *cmd, *prev, *next;
563
564         if (ms->phase != idle || ms->current_req != NULL) {
565                 printk(KERN_ERR "inappropriate mesh_start (phase=%d, ms=%p)",
566                        ms->phase, ms);
567                 return;
568         }
569
570         while (ms->phase == idle) {
571                 prev = NULL;
572                 for (cmd = ms->request_q; ; cmd = (struct scsi_cmnd *) cmd->host_scribble) {
573                         if (cmd == NULL)
574                                 return;
575                         if (ms->tgts[cmd->device->id].current_req == NULL)
576                                 break;
577                         prev = cmd;
578                 }
579                 next = (struct scsi_cmnd *) cmd->host_scribble;
580                 if (prev == NULL)
581                         ms->request_q = next;
582                 else
583                         prev->host_scribble = (void *) next;
584                 if (next == NULL)
585                         ms->request_qtail = prev;
586
587                 mesh_start_cmd(ms, cmd);
588         }
589 }
590
591 static void mesh_done(struct mesh_state *ms, int start_next)
592 {
593         struct scsi_cmnd *cmd;
594         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
595
596         cmd = ms->current_req;
597         ms->current_req = NULL;
598         tp->current_req = NULL;
599         if (cmd) {
600                 cmd->result = (ms->stat << 16) + cmd->SCp.Status;
601                 if (ms->stat == DID_OK)
602                         cmd->result += (cmd->SCp.Message << 8);
603                 if (DEBUG_TARGET(cmd)) {
604                         printk(KERN_DEBUG "mesh_done: result = %x, data_ptr=%d, buflen=%d\n",
605                                cmd->result, ms->data_ptr, scsi_bufflen(cmd));
606 #if 0
607                         /* needs to use sg? */
608                         if ((cmd->cmnd[0] == 0 || cmd->cmnd[0] == 0x12 || cmd->cmnd[0] == 3)
609                             && cmd->request_buffer != 0) {
610                                 unsigned char *b = cmd->request_buffer;
611                                 printk(KERN_DEBUG "buffer = %x %x %x %x %x %x %x %x\n",
612                                        b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7]);
613                         }
614 #endif
615                 }
616                 cmd->SCp.this_residual -= ms->data_ptr;
617                 mesh_completed(ms, cmd);
618         }
619         if (start_next) {
620                 out_8(&ms->mesh->sequence, SEQ_ENBRESEL);
621                 mesh_flush_io(ms->mesh);
622                 udelay(1);
623                 ms->phase = idle;
624                 mesh_start(ms);
625         }
626 }
627
628 static inline void add_sdtr_msg(struct mesh_state *ms)
629 {
630         int i = ms->n_msgout;
631
632         ms->msgout[i] = EXTENDED_MESSAGE;
633         ms->msgout[i+1] = 3;
634         ms->msgout[i+2] = EXTENDED_SDTR;
635         ms->msgout[i+3] = mesh_sync_period/4;
636         ms->msgout[i+4] = (ALLOW_SYNC(ms->conn_tgt)? mesh_sync_offset: 0);
637         ms->n_msgout = i + 5;
638 }
639
640 static void set_sdtr(struct mesh_state *ms, int period, int offset)
641 {
642         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
643         volatile struct mesh_regs __iomem *mr = ms->mesh;
644         int v, tr;
645
646         tp->sdtr_state = sdtr_done;
647         if (offset == 0) {
648                 /* asynchronous */
649                 if (SYNC_OFF(tp->sync_params))
650                         printk(KERN_INFO "mesh: target %d now asynchronous\n",
651                                ms->conn_tgt);
652                 tp->sync_params = ASYNC_PARAMS;
653                 out_8(&mr->sync_params, ASYNC_PARAMS);
654                 return;
655         }
656         /*
657          * We need to compute ceil(clk_freq * period / 500e6) - 2
658          * without incurring overflow.
659          */
660         v = (ms->clk_freq / 5000) * period;
661         if (v <= 250000) {
662                 /* special case: sync_period == 5 * clk_period */
663                 v = 0;
664                 /* units of tr are 100kB/s */
665                 tr = (ms->clk_freq + 250000) / 500000;
666         } else {
667                 /* sync_period == (v + 2) * 2 * clk_period */
668                 v = (v + 99999) / 100000 - 2;
669                 if (v > 15)
670                         v = 15; /* oops */
671                 tr = ((ms->clk_freq / (v + 2)) + 199999) / 200000;
672         }
673         if (offset > 15)
674                 offset = 15;    /* can't happen */
675         tp->sync_params = SYNC_PARAMS(offset, v);
676         out_8(&mr->sync_params, tp->sync_params);
677         printk(KERN_INFO "mesh: target %d synchronous at %d.%d MB/s\n",
678                ms->conn_tgt, tr/10, tr%10);
679 }
680
681 static void start_phase(struct mesh_state *ms)
682 {
683         int i, seq, nb;
684         volatile struct mesh_regs __iomem *mr = ms->mesh;
685         volatile struct dbdma_regs __iomem *md = ms->dma;
686         struct scsi_cmnd *cmd = ms->current_req;
687         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
688
689         dlog(ms, "start_phase nmo/exc/fc/seq = %.8x",
690              MKWORD(ms->n_msgout, mr->exception, mr->fifo_count, mr->sequence));
691         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
692         seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
693         switch (ms->msgphase) {
694         case msg_none:
695                 break;
696
697         case msg_in:
698                 out_8(&mr->count_hi, 0);
699                 out_8(&mr->count_lo, 1);
700                 out_8(&mr->sequence, SEQ_MSGIN + seq);
701                 ms->n_msgin = 0;
702                 return;
703
704         case msg_out:
705                 /*
706                  * To make sure ATN drops before we assert ACK for
707                  * the last byte of the message, we have to do the
708                  * last byte specially.
709                  */
710                 if (ms->n_msgout <= 0) {
711                         printk(KERN_ERR "mesh: msg_out but n_msgout=%d\n",
712                                ms->n_msgout);
713                         mesh_dump_regs(ms);
714                         ms->msgphase = msg_none;
715                         break;
716                 }
717                 if (ALLOW_DEBUG(ms->conn_tgt)) {
718                         printk(KERN_DEBUG "mesh: sending %d msg bytes:",
719                                ms->n_msgout);
720                         for (i = 0; i < ms->n_msgout; ++i)
721                                 printk(" %x", ms->msgout[i]);
722                         printk("\n");
723                 }
724                 dlog(ms, "msgout msg=%.8x", MKWORD(ms->n_msgout, ms->msgout[0],
725                                                 ms->msgout[1], ms->msgout[2]));
726                 out_8(&mr->count_hi, 0);
727                 out_8(&mr->sequence, SEQ_FLUSHFIFO);
728                 mesh_flush_io(mr);
729                 udelay(1);
730                 /*
731                  * If ATN is not already asserted, we assert it, then
732                  * issue a SEQ_MSGOUT to get the mesh to drop ACK.
733                  */
734                 if ((in_8(&mr->bus_status0) & BS0_ATN) == 0) {
735                         dlog(ms, "bus0 was %.2x explicitly asserting ATN", mr->bus_status0);
736                         out_8(&mr->bus_status0, BS0_ATN); /* explicit ATN */
737                         mesh_flush_io(mr);
738                         udelay(1);
739                         out_8(&mr->count_lo, 1);
740                         out_8(&mr->sequence, SEQ_MSGOUT + seq);
741                         out_8(&mr->bus_status0, 0); /* release explicit ATN */
742                         dlog(ms,"hace: after explicit ATN bus0=%.2x",mr->bus_status0);
743                 }
744                 if (ms->n_msgout == 1) {
745                         /*
746                          * We can't issue the SEQ_MSGOUT without ATN
747                          * until the target has asserted REQ.  The logic
748                          * in cmd_complete handles both situations:
749                          * REQ already asserted or not.
750                          */
751                         cmd_complete(ms);
752                 } else {
753                         out_8(&mr->count_lo, ms->n_msgout - 1);
754                         out_8(&mr->sequence, SEQ_MSGOUT + seq);
755                         for (i = 0; i < ms->n_msgout - 1; ++i)
756                                 out_8(&mr->fifo, ms->msgout[i]);
757                 }
758                 return;
759
760         default:
761                 printk(KERN_ERR "mesh bug: start_phase msgphase=%d\n",
762                        ms->msgphase);
763         }
764
765         switch (ms->phase) {
766         case selecting:
767                 out_8(&mr->dest_id, ms->conn_tgt);
768                 out_8(&mr->sequence, SEQ_SELECT + SEQ_ATN);
769                 break;
770         case commanding:
771                 out_8(&mr->sync_params, tp->sync_params);
772                 out_8(&mr->count_hi, 0);
773                 if (cmd) {
774                         out_8(&mr->count_lo, cmd->cmd_len);
775                         out_8(&mr->sequence, SEQ_COMMAND + seq);
776                         for (i = 0; i < cmd->cmd_len; ++i)
777                                 out_8(&mr->fifo, cmd->cmnd[i]);
778                 } else {
779                         out_8(&mr->count_lo, 6);
780                         out_8(&mr->sequence, SEQ_COMMAND + seq);
781                         for (i = 0; i < 6; ++i)
782                                 out_8(&mr->fifo, 0);
783                 }
784                 break;
785         case dataing:
786                 /* transfer data, if any */
787                 if (!ms->dma_started) {
788                         set_dma_cmds(ms, cmd);
789                         out_le32(&md->cmdptr, virt_to_phys(ms->dma_cmds));
790                         out_le32(&md->control, (RUN << 16) | RUN);
791                         ms->dma_started = 1;
792                 }
793                 nb = ms->dma_count;
794                 if (nb > 0xfff0)
795                         nb = 0xfff0;
796                 ms->dma_count -= nb;
797                 ms->data_ptr += nb;
798                 out_8(&mr->count_lo, nb);
799                 out_8(&mr->count_hi, nb >> 8);
800                 out_8(&mr->sequence, (tp->data_goes_out?
801                                 SEQ_DATAOUT: SEQ_DATAIN) + SEQ_DMA_MODE + seq);
802                 break;
803         case statusing:
804                 out_8(&mr->count_hi, 0);
805                 out_8(&mr->count_lo, 1);
806                 out_8(&mr->sequence, SEQ_STATUS + seq);
807                 break;
808         case busfreeing:
809         case disconnecting:
810                 out_8(&mr->sequence, SEQ_ENBRESEL);
811                 mesh_flush_io(mr);
812                 udelay(1);
813                 dlog(ms, "enbresel intr/exc/err/fc=%.8x",
814                      MKWORD(mr->interrupt, mr->exception, mr->error,
815                             mr->fifo_count));
816                 out_8(&mr->sequence, SEQ_BUSFREE);
817                 break;
818         default:
819                 printk(KERN_ERR "mesh: start_phase called with phase=%d\n",
820                        ms->phase);
821                 dumpslog(ms);
822         }
823
824 }
825
826 static inline void get_msgin(struct mesh_state *ms)
827 {
828         volatile struct mesh_regs __iomem *mr = ms->mesh;
829         int i, n;
830
831         n = mr->fifo_count;
832         if (n != 0) {
833                 i = ms->n_msgin;
834                 ms->n_msgin = i + n;
835                 for (; n > 0; --n)
836                         ms->msgin[i++] = in_8(&mr->fifo);
837         }
838 }
839
840 static inline int msgin_length(struct mesh_state *ms)
841 {
842         int b, n;
843
844         n = 1;
845         if (ms->n_msgin > 0) {
846                 b = ms->msgin[0];
847                 if (b == 1) {
848                         /* extended message */
849                         n = ms->n_msgin < 2? 2: ms->msgin[1] + 2;
850                 } else if (0x20 <= b && b <= 0x2f) {
851                         /* 2-byte message */
852                         n = 2;
853                 }
854         }
855         return n;
856 }
857
858 static void reselected(struct mesh_state *ms)
859 {
860         volatile struct mesh_regs __iomem *mr = ms->mesh;
861         struct scsi_cmnd *cmd;
862         struct mesh_target *tp;
863         int b, t, prev;
864
865         switch (ms->phase) {
866         case idle:
867                 break;
868         case arbitrating:
869                 if ((cmd = ms->current_req) != NULL) {
870                         /* put the command back on the queue */
871                         cmd->host_scribble = (void *) ms->request_q;
872                         if (ms->request_q == NULL)
873                                 ms->request_qtail = cmd;
874                         ms->request_q = cmd;
875                         tp = &ms->tgts[cmd->device->id];
876                         tp->current_req = NULL;
877                 }
878                 break;
879         case busfreeing:
880                 ms->phase = reselecting;
881                 mesh_done(ms, 0);
882                 break;
883         case disconnecting:
884                 break;
885         default:
886                 printk(KERN_ERR "mesh: reselected in phase %d/%d tgt %d\n",
887                        ms->msgphase, ms->phase, ms->conn_tgt);
888                 dumplog(ms, ms->conn_tgt);
889                 dumpslog(ms);
890         }
891
892         if (ms->dma_started) {
893                 printk(KERN_ERR "mesh: reselected with DMA started !\n");
894                 halt_dma(ms);
895         }
896         ms->current_req = NULL;
897         ms->phase = dataing;
898         ms->msgphase = msg_in;
899         ms->n_msgout = 0;
900         ms->last_n_msgout = 0;
901         prev = ms->conn_tgt;
902
903         /*
904          * We seem to get abortive reselections sometimes.
905          */
906         while ((in_8(&mr->bus_status1) & BS1_BSY) == 0) {
907                 static int mesh_aborted_resels;
908                 mesh_aborted_resels++;
909                 out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
910                 mesh_flush_io(mr);
911                 udelay(1);
912                 out_8(&mr->sequence, SEQ_ENBRESEL);
913                 mesh_flush_io(mr);
914                 udelay(5);
915                 dlog(ms, "extra resel err/exc/fc = %.6x",
916                      MKWORD(0, mr->error, mr->exception, mr->fifo_count));
917         }
918         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
919         mesh_flush_io(mr);
920         udelay(1);
921         out_8(&mr->sequence, SEQ_ENBRESEL);
922         mesh_flush_io(mr);
923         udelay(1);
924         out_8(&mr->sync_params, ASYNC_PARAMS);
925
926         /*
927          * Find out who reselected us.
928          */
929         if (in_8(&mr->fifo_count) == 0) {
930                 printk(KERN_ERR "mesh: reselection but nothing in fifo?\n");
931                 ms->conn_tgt = ms->host->this_id;
932                 goto bogus;
933         }
934         /* get the last byte in the fifo */
935         do {
936                 b = in_8(&mr->fifo);
937                 dlog(ms, "reseldata %x", b);
938         } while (in_8(&mr->fifo_count));
939         for (t = 0; t < 8; ++t)
940                 if ((b & (1 << t)) != 0 && t != ms->host->this_id)
941                         break;
942         if (b != (1 << t) + (1 << ms->host->this_id)) {
943                 printk(KERN_ERR "mesh: bad reselection data %x\n", b);
944                 ms->conn_tgt = ms->host->this_id;
945                 goto bogus;
946         }
947
948
949         /*
950          * Set up to continue with that target's transfer.
951          */
952         ms->conn_tgt = t;
953         tp = &ms->tgts[t];
954         out_8(&mr->sync_params, tp->sync_params);
955         if (ALLOW_DEBUG(t)) {
956                 printk(KERN_DEBUG "mesh: reselected by target %d\n", t);
957                 printk(KERN_DEBUG "mesh: saved_ptr=%x goes_out=%d cmd=%p\n",
958                        tp->saved_ptr, tp->data_goes_out, tp->current_req);
959         }
960         ms->current_req = tp->current_req;
961         if (tp->current_req == NULL) {
962                 printk(KERN_ERR "mesh: reselected by tgt %d but no cmd!\n", t);
963                 goto bogus;
964         }
965         ms->data_ptr = tp->saved_ptr;
966         dlog(ms, "resel prev tgt=%d", prev);
967         dlog(ms, "resel err/exc=%.4x", MKWORD(0, 0, mr->error, mr->exception));
968         start_phase(ms);
969         return;
970
971 bogus:
972         dumplog(ms, ms->conn_tgt);
973         dumpslog(ms);
974         ms->data_ptr = 0;
975         ms->aborting = 1;
976         start_phase(ms);
977 }
978
979 static void do_abort(struct mesh_state *ms)
980 {
981         ms->msgout[0] = ABORT;
982         ms->n_msgout = 1;
983         ms->aborting = 1;
984         ms->stat = DID_ABORT;
985         dlog(ms, "abort", 0);
986 }
987
988 static void handle_reset(struct mesh_state *ms)
989 {
990         int tgt;
991         struct mesh_target *tp;
992         struct scsi_cmnd *cmd;
993         volatile struct mesh_regs __iomem *mr = ms->mesh;
994
995         for (tgt = 0; tgt < 8; ++tgt) {
996                 tp = &ms->tgts[tgt];
997                 if ((cmd = tp->current_req) != NULL) {
998                         cmd->result = DID_RESET << 16;
999                         tp->current_req = NULL;
1000                         mesh_completed(ms, cmd);
1001                 }
1002                 ms->tgts[tgt].sdtr_state = do_sdtr;
1003                 ms->tgts[tgt].sync_params = ASYNC_PARAMS;
1004         }
1005         ms->current_req = NULL;
1006         while ((cmd = ms->request_q) != NULL) {
1007                 ms->request_q = (struct scsi_cmnd *) cmd->host_scribble;
1008                 cmd->result = DID_RESET << 16;
1009                 mesh_completed(ms, cmd);
1010         }
1011         ms->phase = idle;
1012         ms->msgphase = msg_none;
1013         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1014         out_8(&mr->sequence, SEQ_FLUSHFIFO);
1015         mesh_flush_io(mr);
1016         udelay(1);
1017         out_8(&mr->sync_params, ASYNC_PARAMS);
1018         out_8(&mr->sequence, SEQ_ENBRESEL);
1019 }
1020
1021 static irqreturn_t do_mesh_interrupt(int irq, void *dev_id)
1022 {
1023         unsigned long flags;
1024         struct mesh_state *ms = dev_id;
1025         struct Scsi_Host *dev = ms->host;
1026         
1027         spin_lock_irqsave(dev->host_lock, flags);
1028         mesh_interrupt(ms);
1029         spin_unlock_irqrestore(dev->host_lock, flags);
1030         return IRQ_HANDLED;
1031 }
1032
1033 static void handle_error(struct mesh_state *ms)
1034 {
1035         int err, exc, count;
1036         volatile struct mesh_regs __iomem *mr = ms->mesh;
1037
1038         err = in_8(&mr->error);
1039         exc = in_8(&mr->exception);
1040         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1041         dlog(ms, "error err/exc/fc/cl=%.8x",
1042              MKWORD(err, exc, mr->fifo_count, mr->count_lo));
1043         if (err & ERR_SCSIRESET) {
1044                 /* SCSI bus was reset */
1045                 printk(KERN_INFO "mesh: SCSI bus reset detected: "
1046                        "waiting for end...");
1047                 while ((in_8(&mr->bus_status1) & BS1_RST) != 0)
1048                         udelay(1);
1049                 printk("done\n");
1050                 handle_reset(ms);
1051                 /* request_q is empty, no point in mesh_start() */
1052                 return;
1053         }
1054         if (err & ERR_UNEXPDISC) {
1055                 /* Unexpected disconnect */
1056                 if (exc & EXC_RESELECTED) {
1057                         reselected(ms);
1058                         return;
1059                 }
1060                 if (!ms->aborting) {
1061                         printk(KERN_WARNING "mesh: target %d aborted\n",
1062                                ms->conn_tgt);
1063                         dumplog(ms, ms->conn_tgt);
1064                         dumpslog(ms);
1065                 }
1066                 out_8(&mr->interrupt, INT_CMDDONE);
1067                 ms->stat = DID_ABORT;
1068                 mesh_done(ms, 1);
1069                 return;
1070         }
1071         if (err & ERR_PARITY) {
1072                 if (ms->msgphase == msg_in) {
1073                         printk(KERN_ERR "mesh: msg parity error, target %d\n",
1074                                ms->conn_tgt);
1075                         ms->msgout[0] = MSG_PARITY_ERROR;
1076                         ms->n_msgout = 1;
1077                         ms->msgphase = msg_in_bad;
1078                         cmd_complete(ms);
1079                         return;
1080                 }
1081                 if (ms->stat == DID_OK) {
1082                         printk(KERN_ERR "mesh: parity error, target %d\n",
1083                                ms->conn_tgt);
1084                         ms->stat = DID_PARITY;
1085                 }
1086                 count = (mr->count_hi << 8) + mr->count_lo;
1087                 if (count == 0) {
1088                         cmd_complete(ms);
1089                 } else {
1090                         /* reissue the data transfer command */
1091                         out_8(&mr->sequence, mr->sequence);
1092                 }
1093                 return;
1094         }
1095         if (err & ERR_SEQERR) {
1096                 if (exc & EXC_RESELECTED) {
1097                         /* This can happen if we issue a command to
1098                            get the bus just after the target reselects us. */
1099                         static int mesh_resel_seqerr;
1100                         mesh_resel_seqerr++;
1101                         reselected(ms);
1102                         return;
1103                 }
1104                 if (exc == EXC_PHASEMM) {
1105                         static int mesh_phasemm_seqerr;
1106                         mesh_phasemm_seqerr++;
1107                         phase_mismatch(ms);
1108                         return;
1109                 }
1110                 printk(KERN_ERR "mesh: sequence error (err=%x exc=%x)\n",
1111                        err, exc);
1112         } else {
1113                 printk(KERN_ERR "mesh: unknown error %x (exc=%x)\n", err, exc);
1114         }
1115         mesh_dump_regs(ms);
1116         dumplog(ms, ms->conn_tgt);
1117         if (ms->phase > selecting && (in_8(&mr->bus_status1) & BS1_BSY)) {
1118                 /* try to do what the target wants */
1119                 do_abort(ms);
1120                 phase_mismatch(ms);
1121                 return;
1122         }
1123         ms->stat = DID_ERROR;
1124         mesh_done(ms, 1);
1125 }
1126
1127 static void handle_exception(struct mesh_state *ms)
1128 {
1129         int exc;
1130         volatile struct mesh_regs __iomem *mr = ms->mesh;
1131
1132         exc = in_8(&mr->exception);
1133         out_8(&mr->interrupt, INT_EXCEPTION | INT_CMDDONE);
1134         if (exc & EXC_RESELECTED) {
1135                 static int mesh_resel_exc;
1136                 mesh_resel_exc++;
1137                 reselected(ms);
1138         } else if (exc == EXC_ARBLOST) {
1139                 printk(KERN_DEBUG "mesh: lost arbitration\n");
1140                 ms->stat = DID_BUS_BUSY;
1141                 mesh_done(ms, 1);
1142         } else if (exc == EXC_SELTO) {
1143                 /* selection timed out */
1144                 ms->stat = DID_BAD_TARGET;
1145                 mesh_done(ms, 1);
1146         } else if (exc == EXC_PHASEMM) {
1147                 /* target wants to do something different:
1148                    find out what it wants and do it. */
1149                 phase_mismatch(ms);
1150         } else {
1151                 printk(KERN_ERR "mesh: can't cope with exception %x\n", exc);
1152                 mesh_dump_regs(ms);
1153                 dumplog(ms, ms->conn_tgt);
1154                 do_abort(ms);
1155                 phase_mismatch(ms);
1156         }
1157 }
1158
1159 static void handle_msgin(struct mesh_state *ms)
1160 {
1161         int i, code;
1162         struct scsi_cmnd *cmd = ms->current_req;
1163         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
1164
1165         if (ms->n_msgin == 0)
1166                 return;
1167         code = ms->msgin[0];
1168         if (ALLOW_DEBUG(ms->conn_tgt)) {
1169                 printk(KERN_DEBUG "got %d message bytes:", ms->n_msgin);
1170                 for (i = 0; i < ms->n_msgin; ++i)
1171                         printk(" %x", ms->msgin[i]);
1172                 printk("\n");
1173         }
1174         dlog(ms, "msgin msg=%.8x",
1175              MKWORD(ms->n_msgin, code, ms->msgin[1], ms->msgin[2]));
1176
1177         ms->expect_reply = 0;
1178         ms->n_msgout = 0;
1179         if (ms->n_msgin < msgin_length(ms))
1180                 goto reject;
1181         if (cmd)
1182                 cmd->SCp.Message = code;
1183         switch (code) {
1184         case COMMAND_COMPLETE:
1185                 break;
1186         case EXTENDED_MESSAGE:
1187                 switch (ms->msgin[2]) {
1188                 case EXTENDED_MODIFY_DATA_POINTER:
1189                         ms->data_ptr += (ms->msgin[3] << 24) + ms->msgin[6]
1190                                 + (ms->msgin[4] << 16) + (ms->msgin[5] << 8);
1191                         break;
1192                 case EXTENDED_SDTR:
1193                         if (tp->sdtr_state != sdtr_sent) {
1194                                 /* reply with an SDTR */
1195                                 add_sdtr_msg(ms);
1196                                 /* limit period to at least his value,
1197                                    offset to no more than his */
1198                                 if (ms->msgout[3] < ms->msgin[3])
1199                                         ms->msgout[3] = ms->msgin[3];
1200                                 if (ms->msgout[4] > ms->msgin[4])
1201                                         ms->msgout[4] = ms->msgin[4];
1202                                 set_sdtr(ms, ms->msgout[3], ms->msgout[4]);
1203                                 ms->msgphase = msg_out;
1204                         } else {
1205                                 set_sdtr(ms, ms->msgin[3], ms->msgin[4]);
1206                         }
1207                         break;
1208                 default:
1209                         goto reject;
1210                 }
1211                 break;
1212         case SAVE_POINTERS:
1213                 tp->saved_ptr = ms->data_ptr;
1214                 break;
1215         case RESTORE_POINTERS:
1216                 ms->data_ptr = tp->saved_ptr;
1217                 break;
1218         case DISCONNECT:
1219                 ms->phase = disconnecting;
1220                 break;
1221         case ABORT:
1222                 break;
1223         case MESSAGE_REJECT:
1224                 if (tp->sdtr_state == sdtr_sent)
1225                         set_sdtr(ms, 0, 0);
1226                 break;
1227         case NOP:
1228                 break;
1229         default:
1230                 if (IDENTIFY_BASE <= code && code <= IDENTIFY_BASE + 7) {
1231                         if (cmd == NULL) {
1232                                 do_abort(ms);
1233                                 ms->msgphase = msg_out;
1234                         } else if (code != cmd->device->lun + IDENTIFY_BASE) {
1235                                 printk(KERN_WARNING "mesh: lun mismatch "
1236                                        "(%d != %d) on reselection from "
1237                                        "target %d\n", code - IDENTIFY_BASE,
1238                                        cmd->device->lun, ms->conn_tgt);
1239                         }
1240                         break;
1241                 }
1242                 goto reject;
1243         }
1244         return;
1245
1246  reject:
1247         printk(KERN_WARNING "mesh: rejecting message from target %d:",
1248                ms->conn_tgt);
1249         for (i = 0; i < ms->n_msgin; ++i)
1250                 printk(" %x", ms->msgin[i]);
1251         printk("\n");
1252         ms->msgout[0] = MESSAGE_REJECT;
1253         ms->n_msgout = 1;
1254         ms->msgphase = msg_out;
1255 }
1256
1257 /*
1258  * Set up DMA commands for transferring data.
1259  */
1260 static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd)
1261 {
1262         int i, dma_cmd, total, off, dtot;
1263         struct scatterlist *scl;
1264         struct dbdma_cmd *dcmds;
1265
1266         dma_cmd = ms->tgts[ms->conn_tgt].data_goes_out?
1267                 OUTPUT_MORE: INPUT_MORE;
1268         dcmds = ms->dma_cmds;
1269         dtot = 0;
1270         if (cmd) {
1271                 int nseg;
1272
1273                 cmd->SCp.this_residual = scsi_bufflen(cmd);
1274
1275                 nseg = scsi_dma_map(cmd);
1276                 BUG_ON(nseg < 0);
1277
1278                 if (nseg) {
1279                         total = 0;
1280                         off = ms->data_ptr;
1281
1282                         scsi_for_each_sg(cmd, scl, nseg, i) {
1283                                 u32 dma_addr = sg_dma_address(scl);
1284                                 u32 dma_len = sg_dma_len(scl);
1285                                 
1286                                 total += scl->length;
1287                                 if (off >= dma_len) {
1288                                         off -= dma_len;
1289                                         continue;
1290                                 }
1291                                 if (dma_len > 0xffff)
1292                                         panic("mesh: scatterlist element >= 64k");
1293                                 st_le16(&dcmds->req_count, dma_len - off);
1294                                 st_le16(&dcmds->command, dma_cmd);
1295                                 st_le32(&dcmds->phy_addr, dma_addr + off);
1296                                 dcmds->xfer_status = 0;
1297                                 ++dcmds;
1298                                 dtot += dma_len - off;
1299                                 off = 0;
1300                         }
1301                 }
1302         }
1303         if (dtot == 0) {
1304                 /* Either the target has overrun our buffer,
1305                    or the caller didn't provide a buffer. */
1306                 static char mesh_extra_buf[64];
1307
1308                 dtot = sizeof(mesh_extra_buf);
1309                 st_le16(&dcmds->req_count, dtot);
1310                 st_le32(&dcmds->phy_addr, virt_to_phys(mesh_extra_buf));
1311                 dcmds->xfer_status = 0;
1312                 ++dcmds;
1313         }
1314         dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
1315         st_le16(&dcmds[-1].command, dma_cmd);
1316         memset(dcmds, 0, sizeof(*dcmds));
1317         st_le16(&dcmds->command, DBDMA_STOP);
1318         ms->dma_count = dtot;
1319 }
1320
1321 static void halt_dma(struct mesh_state *ms)
1322 {
1323         volatile struct dbdma_regs __iomem *md = ms->dma;
1324         volatile struct mesh_regs __iomem *mr = ms->mesh;
1325         struct scsi_cmnd *cmd = ms->current_req;
1326         int t, nb;
1327
1328         if (!ms->tgts[ms->conn_tgt].data_goes_out) {
1329                 /* wait a little while until the fifo drains */
1330                 t = 50;
1331                 while (t > 0 && in_8(&mr->fifo_count) != 0
1332                        && (in_le32(&md->status) & ACTIVE) != 0) {
1333                         --t;
1334                         udelay(1);
1335                 }
1336         }
1337         out_le32(&md->control, RUN << 16);      /* turn off RUN bit */
1338         nb = (mr->count_hi << 8) + mr->count_lo;
1339         dlog(ms, "halt_dma fc/count=%.6x",
1340              MKWORD(0, mr->fifo_count, 0, nb));
1341         if (ms->tgts[ms->conn_tgt].data_goes_out)
1342                 nb += mr->fifo_count;
1343         /* nb is the number of bytes not yet transferred
1344            to/from the target. */
1345         ms->data_ptr -= nb;
1346         dlog(ms, "data_ptr %x", ms->data_ptr);
1347         if (ms->data_ptr < 0) {
1348                 printk(KERN_ERR "mesh: halt_dma: data_ptr=%d (nb=%d, ms=%p)\n",
1349                        ms->data_ptr, nb, ms);
1350                 ms->data_ptr = 0;
1351 #ifdef MESH_DBG
1352                 dumplog(ms, ms->conn_tgt);
1353                 dumpslog(ms);
1354 #endif /* MESH_DBG */
1355         } else if (cmd && scsi_bufflen(cmd) &&
1356                    ms->data_ptr > scsi_bufflen(cmd)) {
1357                 printk(KERN_DEBUG "mesh: target %d overrun, "
1358                        "data_ptr=%x total=%x goes_out=%d\n",
1359                        ms->conn_tgt, ms->data_ptr, scsi_bufflen(cmd),
1360                        ms->tgts[ms->conn_tgt].data_goes_out);
1361         }
1362         scsi_dma_unmap(cmd);
1363         ms->dma_started = 0;
1364 }
1365
1366 static void phase_mismatch(struct mesh_state *ms)
1367 {
1368         volatile struct mesh_regs __iomem *mr = ms->mesh;
1369         int phase;
1370
1371         dlog(ms, "phasemm ch/cl/seq/fc=%.8x",
1372              MKWORD(mr->count_hi, mr->count_lo, mr->sequence, mr->fifo_count));
1373         phase = in_8(&mr->bus_status0) & BS0_PHASE;
1374         if (ms->msgphase == msg_out_xxx && phase == BP_MSGOUT) {
1375                 /* output the last byte of the message, without ATN */
1376                 out_8(&mr->count_lo, 1);
1377                 out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
1378                 mesh_flush_io(mr);
1379                 udelay(1);
1380                 out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
1381                 ms->msgphase = msg_out_last;
1382                 return;
1383         }
1384
1385         if (ms->msgphase == msg_in) {
1386                 get_msgin(ms);
1387                 if (ms->n_msgin)
1388                         handle_msgin(ms);
1389         }
1390
1391         if (ms->dma_started)
1392                 halt_dma(ms);
1393         if (mr->fifo_count) {
1394                 out_8(&mr->sequence, SEQ_FLUSHFIFO);
1395                 mesh_flush_io(mr);
1396                 udelay(1);
1397         }
1398
1399         ms->msgphase = msg_none;
1400         switch (phase) {
1401         case BP_DATAIN:
1402                 ms->tgts[ms->conn_tgt].data_goes_out = 0;
1403                 ms->phase = dataing;
1404                 break;
1405         case BP_DATAOUT:
1406                 ms->tgts[ms->conn_tgt].data_goes_out = 1;
1407                 ms->phase = dataing;
1408                 break;
1409         case BP_COMMAND:
1410                 ms->phase = commanding;
1411                 break;
1412         case BP_STATUS:
1413                 ms->phase = statusing;
1414                 break;
1415         case BP_MSGIN:
1416                 ms->msgphase = msg_in;
1417                 ms->n_msgin = 0;
1418                 break;
1419         case BP_MSGOUT:
1420                 ms->msgphase = msg_out;
1421                 if (ms->n_msgout == 0) {
1422                         if (ms->aborting) {
1423                                 do_abort(ms);
1424                         } else {
1425                                 if (ms->last_n_msgout == 0) {
1426                                         printk(KERN_DEBUG
1427                                                "mesh: no msg to repeat\n");
1428                                         ms->msgout[0] = NOP;
1429                                         ms->last_n_msgout = 1;
1430                                 }
1431                                 ms->n_msgout = ms->last_n_msgout;
1432                         }
1433                 }
1434                 break;
1435         default:
1436                 printk(KERN_DEBUG "mesh: unknown scsi phase %x\n", phase);
1437                 ms->stat = DID_ERROR;
1438                 mesh_done(ms, 1);
1439                 return;
1440         }
1441
1442         start_phase(ms);
1443 }
1444
1445 static void cmd_complete(struct mesh_state *ms)
1446 {
1447         volatile struct mesh_regs __iomem *mr = ms->mesh;
1448         struct scsi_cmnd *cmd = ms->current_req;
1449         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
1450         int seq, n, t;
1451
1452         dlog(ms, "cmd_complete fc=%x", mr->fifo_count);
1453         seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
1454         switch (ms->msgphase) {
1455         case msg_out_xxx:
1456                 /* huh?  we expected a phase mismatch */
1457                 ms->n_msgin = 0;
1458                 ms->msgphase = msg_in;
1459                 /* fall through */
1460
1461         case msg_in:
1462                 /* should have some message bytes in fifo */
1463                 get_msgin(ms);
1464                 n = msgin_length(ms);
1465                 if (ms->n_msgin < n) {
1466                         out_8(&mr->count_lo, n - ms->n_msgin);
1467                         out_8(&mr->sequence, SEQ_MSGIN + seq);
1468                 } else {
1469                         ms->msgphase = msg_none;
1470                         handle_msgin(ms);
1471                         start_phase(ms);
1472                 }
1473                 break;
1474
1475         case msg_in_bad:
1476                 out_8(&mr->sequence, SEQ_FLUSHFIFO);
1477                 mesh_flush_io(mr);
1478                 udelay(1);
1479                 out_8(&mr->count_lo, 1);
1480                 out_8(&mr->sequence, SEQ_MSGIN + SEQ_ATN + use_active_neg);
1481                 break;
1482
1483         case msg_out:
1484                 /*
1485                  * To get the right timing on ATN wrt ACK, we have
1486                  * to get the MESH to drop ACK, wait until REQ gets
1487                  * asserted, then drop ATN.  To do this we first
1488                  * issue a SEQ_MSGOUT with ATN and wait for REQ,
1489                  * then change the command to a SEQ_MSGOUT w/o ATN.
1490                  * If we don't see REQ in a reasonable time, we
1491                  * change the command to SEQ_MSGIN with ATN,
1492                  * wait for the phase mismatch interrupt, then
1493                  * issue the SEQ_MSGOUT without ATN.
1494                  */
1495                 out_8(&mr->count_lo, 1);
1496                 out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg + SEQ_ATN);
1497                 t = 30;         /* wait up to 30us */
1498                 while ((in_8(&mr->bus_status0) & BS0_REQ) == 0 && --t >= 0)
1499                         udelay(1);
1500                 dlog(ms, "last_mbyte err/exc/fc/cl=%.8x",
1501                      MKWORD(mr->error, mr->exception,
1502                             mr->fifo_count, mr->count_lo));
1503                 if (in_8(&mr->interrupt) & (INT_ERROR | INT_EXCEPTION)) {
1504                         /* whoops, target didn't do what we expected */
1505                         ms->last_n_msgout = ms->n_msgout;
1506                         ms->n_msgout = 0;
1507                         if (in_8(&mr->interrupt) & INT_ERROR) {
1508                                 printk(KERN_ERR "mesh: error %x in msg_out\n",
1509                                        in_8(&mr->error));
1510                                 handle_error(ms);
1511                                 return;
1512                         }
1513                         if (in_8(&mr->exception) != EXC_PHASEMM)
1514                                 printk(KERN_ERR "mesh: exc %x in msg_out\n",
1515                                        in_8(&mr->exception));
1516                         else
1517                                 printk(KERN_DEBUG "mesh: bs0=%x in msg_out\n",
1518                                        in_8(&mr->bus_status0));
1519                         handle_exception(ms);
1520                         return;
1521                 }
1522                 if (in_8(&mr->bus_status0) & BS0_REQ) {
1523                         out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
1524                         mesh_flush_io(mr);
1525                         udelay(1);
1526                         out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
1527                         ms->msgphase = msg_out_last;
1528                 } else {
1529                         out_8(&mr->sequence, SEQ_MSGIN + use_active_neg + SEQ_ATN);
1530                         ms->msgphase = msg_out_xxx;
1531                 }
1532                 break;
1533
1534         case msg_out_last:
1535                 ms->last_n_msgout = ms->n_msgout;
1536                 ms->n_msgout = 0;
1537                 ms->msgphase = ms->expect_reply? msg_in: msg_none;
1538                 start_phase(ms);
1539                 break;
1540
1541         case msg_none:
1542                 switch (ms->phase) {
1543                 case idle:
1544                         printk(KERN_ERR "mesh: interrupt in idle phase?\n");
1545                         dumpslog(ms);
1546                         return;
1547                 case selecting:
1548                         dlog(ms, "Selecting phase at command completion",0);
1549                         ms->msgout[0] = IDENTIFY(ALLOW_RESEL(ms->conn_tgt),
1550                                                  (cmd? cmd->device->lun: 0));
1551                         ms->n_msgout = 1;
1552                         ms->expect_reply = 0;
1553                         if (ms->aborting) {
1554                                 ms->msgout[0] = ABORT;
1555                                 ms->n_msgout++;
1556                         } else if (tp->sdtr_state == do_sdtr) {
1557                                 /* add SDTR message */
1558                                 add_sdtr_msg(ms);
1559                                 ms->expect_reply = 1;
1560                                 tp->sdtr_state = sdtr_sent;
1561                         }
1562                         ms->msgphase = msg_out;
1563                         /*
1564                          * We need to wait for REQ before dropping ATN.
1565                          * We wait for at most 30us, then fall back to
1566                          * a scheme where we issue a SEQ_COMMAND with ATN,
1567                          * which will give us a phase mismatch interrupt
1568                          * when REQ does come, and then we send the message.
1569                          */
1570                         t = 230;                /* wait up to 230us */
1571                         while ((in_8(&mr->bus_status0) & BS0_REQ) == 0) {
1572                                 if (--t < 0) {
1573                                         dlog(ms, "impatient for req", ms->n_msgout);
1574                                         ms->msgphase = msg_none;
1575                                         break;
1576                                 }
1577                                 udelay(1);
1578                         }
1579                         break;
1580                 case dataing:
1581                         if (ms->dma_count != 0) {
1582                                 start_phase(ms);
1583                                 return;
1584                         }
1585                         /*
1586                          * We can get a phase mismatch here if the target
1587                          * changes to the status phase, even though we have
1588                          * had a command complete interrupt.  Then, if we
1589                          * issue the SEQ_STATUS command, we'll get a sequence
1590                          * error interrupt.  Which isn't so bad except that
1591                          * occasionally the mesh actually executes the
1592                          * SEQ_STATUS *as well as* giving us the sequence
1593                          * error and phase mismatch exception.
1594                          */
1595                         out_8(&mr->sequence, 0);
1596                         out_8(&mr->interrupt,
1597                               INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1598                         halt_dma(ms);
1599                         break;
1600                 case statusing:
1601                         if (cmd) {
1602                                 cmd->SCp.Status = mr->fifo;
1603                                 if (DEBUG_TARGET(cmd))
1604                                         printk(KERN_DEBUG "mesh: status is %x\n",
1605                                                cmd->SCp.Status);
1606                         }
1607                         ms->msgphase = msg_in;
1608                         break;
1609                 case busfreeing:
1610                         mesh_done(ms, 1);
1611                         return;
1612                 case disconnecting:
1613                         ms->current_req = NULL;
1614                         ms->phase = idle;
1615                         mesh_start(ms);
1616                         return;
1617                 default:
1618                         break;
1619                 }
1620                 ++ms->phase;
1621                 start_phase(ms);
1622                 break;
1623         }
1624 }
1625
1626
1627 /*
1628  * Called by midlayer with host locked to queue a new
1629  * request
1630  */
1631 static int mesh_queue(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
1632 {
1633         struct mesh_state *ms;
1634
1635         cmd->scsi_done = done;
1636         cmd->host_scribble = NULL;
1637
1638         ms = (struct mesh_state *) cmd->device->host->hostdata;
1639
1640         if (ms->request_q == NULL)
1641                 ms->request_q = cmd;
1642         else
1643                 ms->request_qtail->host_scribble = (void *) cmd;
1644         ms->request_qtail = cmd;
1645
1646         if (ms->phase == idle)
1647                 mesh_start(ms);
1648
1649         return 0;
1650 }
1651
1652 /*
1653  * Called to handle interrupts, either call by the interrupt
1654  * handler (do_mesh_interrupt) or by other functions in
1655  * exceptional circumstances
1656  */
1657 static void mesh_interrupt(struct mesh_state *ms)
1658 {
1659         volatile struct mesh_regs __iomem *mr = ms->mesh;
1660         int intr;
1661
1662 #if 0
1663         if (ALLOW_DEBUG(ms->conn_tgt))
1664                 printk(KERN_DEBUG "mesh_intr, bs0=%x int=%x exc=%x err=%x "
1665                        "phase=%d msgphase=%d\n", mr->bus_status0,
1666                        mr->interrupt, mr->exception, mr->error,
1667                        ms->phase, ms->msgphase);
1668 #endif
1669         while ((intr = in_8(&mr->interrupt)) != 0) {
1670                 dlog(ms, "interrupt intr/err/exc/seq=%.8x", 
1671                      MKWORD(intr, mr->error, mr->exception, mr->sequence));
1672                 if (intr & INT_ERROR) {
1673                         handle_error(ms);
1674                 } else if (intr & INT_EXCEPTION) {
1675                         handle_exception(ms);
1676                 } else if (intr & INT_CMDDONE) {
1677                         out_8(&mr->interrupt, INT_CMDDONE);
1678                         cmd_complete(ms);
1679                 }
1680         }
1681 }
1682
1683 /* Todo: here we can at least try to remove the command from the
1684  * queue if it isn't connected yet, and for pending command, assert
1685  * ATN until the bus gets freed.
1686  */
1687 static int mesh_abort(struct scsi_cmnd *cmd)
1688 {
1689         struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
1690
1691         printk(KERN_DEBUG "mesh_abort(%p)\n", cmd);
1692         mesh_dump_regs(ms);
1693         dumplog(ms, cmd->device->id);
1694         dumpslog(ms);
1695         return FAILED;
1696 }
1697
1698 /*
1699  * Called by the midlayer with the lock held to reset the
1700  * SCSI host and bus.
1701  * The midlayer will wait for devices to come back, we don't need
1702  * to do that ourselves
1703  */
1704 static int mesh_host_reset(struct scsi_cmnd *cmd)
1705 {
1706         struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
1707         volatile struct mesh_regs __iomem *mr = ms->mesh;
1708         volatile struct dbdma_regs __iomem *md = ms->dma;
1709         unsigned long flags;
1710
1711         printk(KERN_DEBUG "mesh_host_reset\n");
1712
1713         spin_lock_irqsave(ms->host->host_lock, flags);
1714
1715         /* Reset the controller & dbdma channel */
1716         out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16);   /* stop dma */
1717         out_8(&mr->exception, 0xff);    /* clear all exception bits */
1718         out_8(&mr->error, 0xff);        /* clear all error bits */
1719         out_8(&mr->sequence, SEQ_RESETMESH);
1720         mesh_flush_io(mr);
1721         udelay(1);
1722         out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1723         out_8(&mr->source_id, ms->host->this_id);
1724         out_8(&mr->sel_timeout, 25);    /* 250ms */
1725         out_8(&mr->sync_params, ASYNC_PARAMS);
1726
1727         /* Reset the bus */
1728         out_8(&mr->bus_status1, BS1_RST);       /* assert RST */
1729         mesh_flush_io(mr);
1730         udelay(30);                     /* leave it on for >= 25us */
1731         out_8(&mr->bus_status1, 0);     /* negate RST */
1732
1733         /* Complete pending commands */
1734         handle_reset(ms);
1735         
1736         spin_unlock_irqrestore(ms->host->host_lock, flags);
1737         return SUCCESS;
1738 }
1739
1740 static void set_mesh_power(struct mesh_state *ms, int state)
1741 {
1742         if (!machine_is(powermac))
1743                 return;
1744         if (state) {
1745                 pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 1);
1746                 msleep(200);
1747         } else {
1748                 pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 0);
1749                 msleep(10);
1750         }
1751 }
1752
1753
1754 #ifdef CONFIG_PM
1755 static int mesh_suspend(struct macio_dev *mdev, pm_message_t mesg)
1756 {
1757         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1758         unsigned long flags;
1759
1760         switch (mesg.event) {
1761         case PM_EVENT_SUSPEND:
1762         case PM_EVENT_HIBERNATE:
1763         case PM_EVENT_FREEZE:
1764                 break;
1765         default:
1766                 return 0;
1767         }
1768         if (ms->phase == sleeping)
1769                 return 0;
1770
1771         scsi_block_requests(ms->host);
1772         spin_lock_irqsave(ms->host->host_lock, flags);
1773         while(ms->phase != idle) {
1774                 spin_unlock_irqrestore(ms->host->host_lock, flags);
1775                 msleep(10);
1776                 spin_lock_irqsave(ms->host->host_lock, flags);
1777         }
1778         ms->phase = sleeping;
1779         spin_unlock_irqrestore(ms->host->host_lock, flags);
1780         disable_irq(ms->meshintr);
1781         set_mesh_power(ms, 0);
1782
1783         return 0;
1784 }
1785
1786 static int mesh_resume(struct macio_dev *mdev)
1787 {
1788         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1789         unsigned long flags;
1790
1791         if (ms->phase != sleeping)
1792                 return 0;
1793
1794         set_mesh_power(ms, 1);
1795         mesh_init(ms);
1796         spin_lock_irqsave(ms->host->host_lock, flags);
1797         mesh_start(ms);
1798         spin_unlock_irqrestore(ms->host->host_lock, flags);
1799         enable_irq(ms->meshintr);
1800         scsi_unblock_requests(ms->host);
1801
1802         return 0;
1803 }
1804
1805 #endif /* CONFIG_PM */
1806
1807 /*
1808  * If we leave drives set for synchronous transfers (especially
1809  * CDROMs), and reboot to MacOS, it gets confused, poor thing.
1810  * So, on reboot we reset the SCSI bus.
1811  */
1812 static int mesh_shutdown(struct macio_dev *mdev)
1813 {
1814         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1815         volatile struct mesh_regs __iomem *mr;
1816         unsigned long flags;
1817
1818         printk(KERN_INFO "resetting MESH scsi bus(es)\n");
1819         spin_lock_irqsave(ms->host->host_lock, flags);
1820         mr = ms->mesh;
1821         out_8(&mr->intr_mask, 0);
1822         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1823         out_8(&mr->bus_status1, BS1_RST);
1824         mesh_flush_io(mr);
1825         udelay(30);
1826         out_8(&mr->bus_status1, 0);
1827         spin_unlock_irqrestore(ms->host->host_lock, flags);
1828
1829         return 0;
1830 }
1831
1832 static struct scsi_host_template mesh_template = {
1833         .proc_name                      = "mesh",
1834         .name                           = "MESH",
1835         .queuecommand                   = mesh_queue,
1836         .eh_abort_handler               = mesh_abort,
1837         .eh_host_reset_handler          = mesh_host_reset,
1838         .can_queue                      = 20,
1839         .this_id                        = 7,
1840         .sg_tablesize                   = SG_ALL,
1841         .cmd_per_lun                    = 2,
1842         .use_clustering                 = DISABLE_CLUSTERING,
1843 };
1844
1845 static int mesh_probe(struct macio_dev *mdev, const struct of_device_id *match)
1846 {
1847         struct device_node *mesh = macio_get_of_node(mdev);
1848         struct pci_dev* pdev = macio_get_pci_dev(mdev);
1849         int tgt, minper;
1850         const int *cfp;
1851         struct mesh_state *ms;
1852         struct Scsi_Host *mesh_host;
1853         void *dma_cmd_space;
1854         dma_addr_t dma_cmd_bus;
1855
1856         switch (mdev->bus->chip->type) {
1857         case macio_heathrow:
1858         case macio_gatwick:
1859         case macio_paddington:
1860                 use_active_neg = 0;
1861                 break;
1862         default:
1863                 use_active_neg = SEQ_ACTIVE_NEG;
1864         }
1865
1866         if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
1867                 printk(KERN_ERR "mesh: expected 2 addrs and 2 intrs"
1868                        " (got %d,%d)\n", macio_resource_count(mdev),
1869                        macio_irq_count(mdev));
1870                 return -ENODEV;
1871         }
1872
1873         if (macio_request_resources(mdev, "mesh") != 0) {
1874                 printk(KERN_ERR "mesh: unable to request memory resources");
1875                 return -EBUSY;
1876         }
1877         mesh_host = scsi_host_alloc(&mesh_template, sizeof(struct mesh_state));
1878         if (mesh_host == NULL) {
1879                 printk(KERN_ERR "mesh: couldn't register host");
1880                 goto out_release;
1881         }
1882         
1883         /* Old junk for root discovery, that will die ultimately */
1884 #if !defined(MODULE)
1885         note_scsi_host(mesh, mesh_host);
1886 #endif
1887
1888         mesh_host->base = macio_resource_start(mdev, 0);
1889         mesh_host->irq = macio_irq(mdev, 0);
1890         ms = (struct mesh_state *) mesh_host->hostdata;
1891         macio_set_drvdata(mdev, ms);
1892         ms->host = mesh_host;
1893         ms->mdev = mdev;
1894         ms->pdev = pdev;
1895         
1896         ms->mesh = ioremap(macio_resource_start(mdev, 0), 0x1000);
1897         if (ms->mesh == NULL) {
1898                 printk(KERN_ERR "mesh: can't map registers\n");
1899                 goto out_free;
1900         }               
1901         ms->dma = ioremap(macio_resource_start(mdev, 1), 0x1000);
1902         if (ms->dma == NULL) {
1903                 printk(KERN_ERR "mesh: can't map registers\n");
1904                 iounmap(ms->mesh);
1905                 goto out_free;
1906         }
1907
1908         ms->meshintr = macio_irq(mdev, 0);
1909         ms->dmaintr = macio_irq(mdev, 1);
1910
1911         /* Space for dma command list: +1 for stop command,
1912          * +1 to allow for aligning.
1913          */
1914         ms->dma_cmd_size = (mesh_host->sg_tablesize + 2) * sizeof(struct dbdma_cmd);
1915
1916         /* We use the PCI APIs for now until the generic one gets fixed
1917          * enough or until we get some macio-specific versions
1918          */
1919         dma_cmd_space = pci_alloc_consistent(macio_get_pci_dev(mdev),
1920                                              ms->dma_cmd_size,
1921                                              &dma_cmd_bus);
1922         if (dma_cmd_space == NULL) {
1923                 printk(KERN_ERR "mesh: can't allocate DMA table\n");
1924                 goto out_unmap;
1925         }
1926         memset(dma_cmd_space, 0, ms->dma_cmd_size);
1927
1928         ms->dma_cmds = (struct dbdma_cmd *) DBDMA_ALIGN(dma_cmd_space);
1929         ms->dma_cmd_space = dma_cmd_space;
1930         ms->dma_cmd_bus = dma_cmd_bus + ((unsigned long)ms->dma_cmds)
1931                 - (unsigned long)dma_cmd_space;
1932         ms->current_req = NULL;
1933         for (tgt = 0; tgt < 8; ++tgt) {
1934                 ms->tgts[tgt].sdtr_state = do_sdtr;
1935                 ms->tgts[tgt].sync_params = ASYNC_PARAMS;
1936                 ms->tgts[tgt].current_req = NULL;
1937         }
1938
1939         if ((cfp = of_get_property(mesh, "clock-frequency", NULL)))
1940                 ms->clk_freq = *cfp;
1941         else {
1942                 printk(KERN_INFO "mesh: assuming 50MHz clock frequency\n");
1943                 ms->clk_freq = 50000000;
1944         }
1945
1946         /* The maximum sync rate is clock / 5; increase
1947          * mesh_sync_period if necessary.
1948          */
1949         minper = 1000000000 / (ms->clk_freq / 5); /* ns */
1950         if (mesh_sync_period < minper)
1951                 mesh_sync_period = minper;
1952
1953         /* Power up the chip */
1954         set_mesh_power(ms, 1);
1955
1956         /* Set it up */
1957         mesh_init(ms);
1958
1959         /* Request interrupt */
1960         if (request_irq(ms->meshintr, do_mesh_interrupt, 0, "MESH", ms)) {
1961                 printk(KERN_ERR "MESH: can't get irq %d\n", ms->meshintr);
1962                 goto out_shutdown;
1963         }
1964
1965         /* Add scsi host & scan */
1966         if (scsi_add_host(mesh_host, &mdev->ofdev.dev))
1967                 goto out_release_irq;
1968         scsi_scan_host(mesh_host);
1969
1970         return 0;
1971
1972  out_release_irq:
1973         free_irq(ms->meshintr, ms);
1974  out_shutdown:
1975         /* shutdown & reset bus in case of error or macos can be confused
1976          * at reboot if the bus was set to synchronous mode already
1977          */
1978         mesh_shutdown(mdev);
1979         set_mesh_power(ms, 0);
1980         pci_free_consistent(macio_get_pci_dev(mdev), ms->dma_cmd_size,
1981                             ms->dma_cmd_space, ms->dma_cmd_bus);
1982  out_unmap:
1983         iounmap(ms->dma);
1984         iounmap(ms->mesh);
1985  out_free:
1986         scsi_host_put(mesh_host);
1987  out_release:
1988         macio_release_resources(mdev);
1989
1990         return -ENODEV;
1991 }
1992
1993 static int mesh_remove(struct macio_dev *mdev)
1994 {
1995         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1996         struct Scsi_Host *mesh_host = ms->host;
1997
1998         scsi_remove_host(mesh_host);
1999
2000         free_irq(ms->meshintr, ms);
2001
2002         /* Reset scsi bus */
2003         mesh_shutdown(mdev);
2004
2005         /* Shut down chip & termination */
2006         set_mesh_power(ms, 0);
2007
2008         /* Unmap registers & dma controller */
2009         iounmap(ms->mesh);
2010         iounmap(ms->dma);
2011
2012         /* Free DMA commands memory */
2013         pci_free_consistent(macio_get_pci_dev(mdev), ms->dma_cmd_size,
2014                             ms->dma_cmd_space, ms->dma_cmd_bus);
2015
2016         /* Release memory resources */
2017         macio_release_resources(mdev);
2018
2019         scsi_host_put(mesh_host);
2020
2021         return 0;
2022 }
2023
2024
2025 static struct of_device_id mesh_match[] = 
2026 {
2027         {
2028         .name           = "mesh",
2029         },
2030         {
2031         .type           = "scsi",
2032         .compatible     = "chrp,mesh0"
2033         },
2034         {},
2035 };
2036 MODULE_DEVICE_TABLE (of, mesh_match);
2037
2038 static struct macio_driver mesh_driver = 
2039 {
2040         .name           = "mesh",
2041         .match_table    = mesh_match,
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
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
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);