sbc.c revision 1.53 1 /* $NetBSD: sbc.c,v 1.53 2008/04/04 16:00:57 tsutsui Exp $ */
2
3 /*
4 * Copyright (C) 1996 Scott Reynolds. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /*
30 * This file contains only the machine-dependent parts of the mac68k
31 * NCR 5380 SCSI driver. (Autoconfig stuff and PDMA functions.)
32 * The machine-independent parts are in ncr5380sbc.c
33 *
34 * Supported hardware includes:
35 * Macintosh II family 5380-based controller
36 *
37 * Credits, history:
38 *
39 * Scott Reynolds wrote this module, based on work by Allen Briggs
40 * (mac68k), Gordon W. Ross and David Jones (sun3), and Leo Weppelman
41 * (atari). Thanks to Allen for supplying crucial interpretation of the
42 * NetBSD/mac68k 1.1 'ncrscsi' driver. Also, Allen, Gordon, and Jason
43 * Thorpe all helped to refine this code, and were considerable sources
44 * of moral support.
45 */
46
47 #include <sys/cdefs.h>
48 __KERNEL_RCSID(0, "$NetBSD: sbc.c,v 1.53 2008/04/04 16:00:57 tsutsui Exp $");
49
50 #include "opt_ddb.h"
51
52 #include <sys/types.h>
53 #include <sys/param.h>
54 #include <sys/systm.h>
55 #include <sys/kernel.h>
56 #include <sys/errno.h>
57 #include <sys/device.h>
58 #include <sys/buf.h>
59 #include <sys/proc.h>
60 #include <sys/user.h>
61
62 #include <dev/scsipi/scsi_all.h>
63 #include <dev/scsipi/scsipi_all.h>
64 #include <dev/scsipi/scsipi_debug.h>
65 #include <dev/scsipi/scsiconf.h>
66
67 #include <dev/ic/ncr5380reg.h>
68 #include <dev/ic/ncr5380var.h>
69
70 #include <machine/cpu.h>
71 #include <machine/viareg.h>
72
73 #include <mac68k/dev/sbcreg.h>
74 #include <mac68k/dev/sbcvar.h>
75
76 /* SBC_DEBUG -- relies on DDB */
77 #ifdef SBC_DEBUG
78 # define SBC_DB_INTR 0x01
79 # define SBC_DB_DMA 0x02
80 # define SBC_DB_REG 0x04
81 # define SBC_DB_BREAK 0x08
82 # ifndef DDB
83 # define Debugger() printf("Debug: sbc.c:%d\n", __LINE__)
84 # endif
85 # define SBC_BREAK \
86 do { if (sbc_debug & SBC_DB_BREAK) Debugger(); } while (0)
87 #else
88 # define SBC_BREAK
89 #endif
90
91
92 int sbc_debug = 0 /* | SBC_DB_INTR | SBC_DB_DMA */;
93 int sbc_link_flags = 0 /* | SDEV_DB2 */;
94 int sbc_options = 0 /* | SBC_PDMA */;
95
96 extern label_t *nofault;
97 extern void * m68k_fault_addr;
98
99 static int sbc_wait_busy(struct ncr5380_softc *);
100 static int sbc_ready(struct ncr5380_softc *);
101 static int sbc_wait_dreq(struct ncr5380_softc *);
102
103
104 /***
105 * General support for Mac-specific SCSI logic.
106 ***/
107
108 /* These are used in the following inline functions. */
109 int sbc_wait_busy_timo = 1000 * 5000; /* X2 = 10 S. */
110 int sbc_ready_timo = 1000 * 5000; /* X2 = 10 S. */
111 int sbc_wait_dreq_timo = 1000 * 5000; /* X2 = 10 S. */
112
113 /* Return zero on success. */
114 static inline int
115 sbc_wait_busy(struct ncr5380_softc *sc)
116 {
117 int timo = sbc_wait_busy_timo;
118 for (;;) {
119 if (SCI_BUSY(sc)) {
120 timo = 0; /* return 0 */
121 break;
122 }
123 if (--timo < 0)
124 break; /* return -1 */
125 delay(2);
126 }
127 return (timo);
128 }
129
130 static inline int
131 sbc_ready(struct ncr5380_softc *sc)
132 {
133 int timo = sbc_ready_timo;
134
135 for (;;) {
136 if ((*sc->sci_csr & (SCI_CSR_DREQ|SCI_CSR_PHASE_MATCH))
137 == (SCI_CSR_DREQ|SCI_CSR_PHASE_MATCH)) {
138 timo = 0;
139 break;
140 }
141 if (((*sc->sci_csr & SCI_CSR_PHASE_MATCH) == 0)
142 || (SCI_BUSY(sc) == 0)) {
143 timo = -1;
144 break;
145 }
146 if (--timo < 0)
147 break; /* return -1 */
148 delay(2);
149 }
150 return (timo);
151 }
152
153 static inline int
154 sbc_wait_dreq(struct ncr5380_softc *sc)
155 {
156 int timo = sbc_wait_dreq_timo;
157
158 for (;;) {
159 if ((*sc->sci_csr & (SCI_CSR_DREQ|SCI_CSR_PHASE_MATCH))
160 == (SCI_CSR_DREQ|SCI_CSR_PHASE_MATCH)) {
161 timo = 0;
162 break;
163 }
164 if (--timo < 0)
165 break; /* return -1 */
166 delay(2);
167 }
168 return (timo);
169 }
170
171 void
172 sbc_irq_intr(void *p)
173 {
174 struct ncr5380_softc *ncr_sc = p;
175 struct sbc_softc *sc = (struct sbc_softc *)ncr_sc;
176 int claimed = 0;
177
178 /* How we ever arrive here without IRQ set is a mystery... */
179 if (*ncr_sc->sci_csr & SCI_CSR_INT) {
180 #ifdef SBC_DEBUG
181 if (sbc_debug & SBC_DB_INTR)
182 decode_5380_intr(ncr_sc);
183 #endif
184 if (!cold)
185 claimed = ncr5380_intr(ncr_sc);
186 if (!claimed) {
187 if (((*ncr_sc->sci_csr & ~SCI_CSR_PHASE_MATCH) == SCI_CSR_INT)
188 && ((*ncr_sc->sci_bus_csr & ~SCI_BUS_RST) == 0)) {
189 SCI_CLR_INTR(ncr_sc); /* RST interrupt */
190 if (sc->sc_clrintr)
191 (*sc->sc_clrintr)(ncr_sc);
192 }
193 #ifdef SBC_DEBUG
194 else {
195 printf("%s: spurious intr\n",
196 device_xname(ncr_sc->sc_dev));
197 SBC_BREAK;
198 }
199 #endif
200 }
201 }
202 }
203
204 #ifdef SBC_DEBUG
205 void
206 decode_5380_intr(struct ncr5380_softc *ncr_sc)
207 {
208 u_int8_t csr = *ncr_sc->sci_csr;
209 u_int8_t bus_csr = *ncr_sc->sci_bus_csr;
210
211 if (((csr & ~(SCI_CSR_PHASE_MATCH | SCI_CSR_ATN)) == SCI_CSR_INT) &&
212 ((bus_csr & ~(SCI_BUS_MSG | SCI_BUS_CD | SCI_BUS_IO | SCI_BUS_DBP)) == SCI_BUS_SEL)) {
213 if (csr & SCI_BUS_IO)
214 printf("%s: reselect\n", device_xname(ncr_sc->sc_dev));
215 else
216 printf("%s: select\n", device_xname(ncr_sc->sc_dev));
217 } else if (((csr & ~SCI_CSR_ACK) == (SCI_CSR_DONE | SCI_CSR_INT)) &&
218 ((bus_csr & (SCI_BUS_RST | SCI_BUS_BSY | SCI_BUS_SEL)) == SCI_BUS_BSY))
219 printf("%s: DMA eop\n", device_xname(ncr_sc->sc_dev));
220 else if (((csr & ~SCI_CSR_PHASE_MATCH) == SCI_CSR_INT) &&
221 ((bus_csr & ~SCI_BUS_RST) == 0))
222 printf("%s: bus reset\n", device_xname(ncr_sc->sc_dev));
223 else if (((csr & ~(SCI_CSR_DREQ | SCI_CSR_ATN | SCI_CSR_ACK)) == (SCI_CSR_PERR | SCI_CSR_INT | SCI_CSR_PHASE_MATCH)) &&
224 ((bus_csr & (SCI_BUS_RST | SCI_BUS_BSY | SCI_BUS_SEL)) == SCI_BUS_BSY))
225 printf("%s: parity error\n", device_xname(ncr_sc->sc_dev));
226 else if (((csr & ~SCI_CSR_ATN) == SCI_CSR_INT) &&
227 ((bus_csr & (SCI_BUS_RST | SCI_BUS_BSY | SCI_BUS_REQ | SCI_BUS_SEL)) == (SCI_BUS_BSY | SCI_BUS_REQ)))
228 printf("%s: phase mismatch\n", device_xname(ncr_sc->sc_dev));
229 else if (((csr & ~SCI_CSR_PHASE_MATCH) == (SCI_CSR_INT | SCI_CSR_DISC)) &&
230 (bus_csr == 0))
231 printf("%s: disconnect\n", device_xname(ncr_sc->sc_dev));
232 else
233 printf("%s: unknown intr: csr=%x, bus_csr=%x\n",
234 device_xname(ncr_sc->sc_dev), csr, bus_csr);
235 }
236 #endif
237
238
239 /***
240 * The following code implements polled PDMA.
241 ***/
242
243 int
244 sbc_pdma_in(struct ncr5380_softc *ncr_sc, int phase, int datalen, u_char *data)
245 {
246 struct sbc_softc *sc = (struct sbc_softc *)ncr_sc;
247 volatile u_int32_t *long_data = (u_int32_t *)sc->sc_drq_addr;
248 volatile u_int8_t *byte_data = (u_int8_t *)sc->sc_nodrq_addr;
249 label_t faultbuf;
250 int resid, s;
251
252 if (datalen < ncr_sc->sc_min_dma_len ||
253 (sc->sc_options & SBC_PDMA) == 0)
254 return ncr5380_pio_in(ncr_sc, phase, datalen, data);
255
256 s = splbio();
257 if (sbc_wait_busy(ncr_sc)) {
258 splx(s);
259 return 0;
260 }
261
262 *ncr_sc->sci_mode |= SCI_MODE_DMA;
263 *ncr_sc->sci_irecv = 0;
264
265 resid = datalen;
266
267 /*
268 * Setup for a possible bus error caused by SCSI controller
269 * switching out of DATA OUT before we're done with the
270 * current transfer. (See comment before sbc_drq_intr().)
271 */
272 nofault = &faultbuf;
273 if (setjmp(nofault)) {
274 goto interrupt;
275 }
276
277 #define R4 *(u_int32_t *)data = *long_data, data += 4;
278 #define R1 *(u_int8_t *)data = *byte_data, data += 1;
279 for (; resid >= 128; resid -= 128) {
280 if (sbc_ready(ncr_sc))
281 goto interrupt;
282 R4; R4; R4; R4; R4; R4; R4; R4;
283 R4; R4; R4; R4; R4; R4; R4; R4;
284 R4; R4; R4; R4; R4; R4; R4; R4;
285 R4; R4; R4; R4; R4; R4; R4; R4; /* 128 */
286 }
287 while (resid) {
288 if (sbc_ready(ncr_sc))
289 goto interrupt;
290 R1;
291 resid--;
292 }
293 #undef R4
294 #undef R1
295
296 interrupt:
297 nofault = NULL;
298 SCI_CLR_INTR(ncr_sc);
299 *ncr_sc->sci_mode &= ~SCI_MODE_DMA;
300 *ncr_sc->sci_icmd = 0;
301 splx(s);
302 return (datalen - resid);
303 }
304
305 int
306 sbc_pdma_out(struct ncr5380_softc *ncr_sc, int phase, int datalen, u_char *data)
307 {
308 struct sbc_softc *sc = (struct sbc_softc *)ncr_sc;
309 volatile u_int32_t *long_data = (u_int32_t *)sc->sc_drq_addr;
310 volatile u_int8_t *byte_data = (u_int8_t *)sc->sc_nodrq_addr;
311 label_t faultbuf;
312 int resid, s;
313 u_int8_t icmd;
314
315 #if 1
316 /* Work around lame gcc initialization bug */
317 (void)&data;
318 #endif
319
320 if (datalen < ncr_sc->sc_min_dma_len ||
321 (sc->sc_options & SBC_PDMA) == 0)
322 return ncr5380_pio_out(ncr_sc, phase, datalen, data);
323
324 s = splbio();
325 if (sbc_wait_busy(ncr_sc)) {
326 splx(s);
327 return 0;
328 }
329
330 icmd = *(ncr_sc->sci_icmd) & SCI_ICMD_RMASK;
331 *ncr_sc->sci_icmd = icmd | SCI_ICMD_DATA;
332 *ncr_sc->sci_mode |= SCI_MODE_DMA;
333 *ncr_sc->sci_dma_send = 0;
334
335 /*
336 * Setup for a possible bus error caused by SCSI controller
337 * switching out of DATA OUT before we're done with the
338 * current transfer. (See comment before sbc_drq_intr().)
339 */
340 nofault = &faultbuf;
341
342 if (setjmp(nofault)) {
343 printf("buf = 0x%lx, fault = 0x%lx\n",
344 (u_long)sc->sc_drq_addr, (u_long)m68k_fault_addr);
345 panic("Unexpected bus error in sbc_pdma_out()");
346 }
347
348 #define W1 *byte_data = *(u_int8_t *)data, data += 1
349 #define W4 *long_data = *(u_int32_t *)data, data += 4
350 for (resid = datalen; resid >= 64; resid -= 64) {
351 if (sbc_ready(ncr_sc))
352 goto interrupt;
353 W1;
354 if (sbc_ready(ncr_sc))
355 goto interrupt;
356 W1;
357 if (sbc_ready(ncr_sc))
358 goto interrupt;
359 W1;
360 if (sbc_ready(ncr_sc))
361 goto interrupt;
362 W1;
363 if (sbc_ready(ncr_sc))
364 goto interrupt;
365 W4; W4; W4; W4;
366 W4; W4; W4; W4;
367 W4; W4; W4; W4;
368 W4; W4; W4;
369 }
370 while (resid) {
371 if (sbc_ready(ncr_sc))
372 goto interrupt;
373 W1;
374 resid--;
375 }
376 #undef W1
377 #undef W4
378 if (sbc_wait_dreq(ncr_sc))
379 printf("%s: timeout waiting for DREQ.\n",
380 device_xname(ncr_sc->sc_dev));
381
382 *byte_data = 0;
383 goto done;
384
385 interrupt:
386 if ((*ncr_sc->sci_csr & SCI_CSR_PHASE_MATCH) == 0) {
387 *ncr_sc->sci_icmd = icmd & ~SCI_ICMD_DATA;
388 --resid;
389 }
390
391 done:
392 SCI_CLR_INTR(ncr_sc);
393 *ncr_sc->sci_mode &= ~SCI_MODE_DMA;
394 *ncr_sc->sci_icmd = icmd;
395 splx(s);
396 return (datalen - resid);
397 }
398
399
400 /***
401 * The following code implements interrupt-driven PDMA.
402 ***/
403
404 /*
405 * This is the meat of the PDMA transfer.
406 * When we get here, we shove data as fast as the mac can take it.
407 * We depend on several things:
408 * * All macs after the Mac Plus that have a 5380 chip should have a general
409 * logic IC that handshakes data for blind transfers.
410 * * If the SCSI controller finishes sending/receiving data before we do,
411 * the same general logic IC will generate a /BERR for us in short order.
412 * * The fault address for said /BERR minus the base address for the
413 * transfer will be the amount of data that was actually written.
414 *
415 * We use the nofault flag and the setjmp/longjmp in locore.s so we can
416 * detect and handle the bus error for early termination of a command.
417 * This is usually caused by a disconnecting target.
418 */
419 void
420 sbc_drq_intr(void *p)
421 {
422 struct sbc_softc *sc = (struct sbc_softc *)p;
423 struct ncr5380_softc *ncr_sc = (struct ncr5380_softc *)p;
424 struct sci_req *sr = ncr_sc->sc_current;
425 struct sbc_pdma_handle *dh = sr->sr_dma_hand;
426 label_t faultbuf;
427 volatile u_int32_t *long_drq;
428 u_int32_t *long_data;
429 volatile u_int8_t *drq = 0; /* XXX gcc4 -Wuninitialized */
430 u_int8_t *data;
431 int count, dcount, resid;
432 u_int8_t tmp;
433
434 /*
435 * If we're not ready to xfer data, or have no more, just return.
436 */
437 if ((*ncr_sc->sci_csr & SCI_CSR_DREQ) == 0 || dh->dh_len == 0)
438 return;
439
440 #ifdef SBC_DEBUG
441 if (sbc_debug & SBC_DB_INTR)
442 printf("%s: drq intr, dh_len=0x%x, dh_flags=0x%x\n",
443 device_xname(ncr_sc->sc_dev), dh->dh_len, dh->dh_flags);
444 #endif
445
446 /*
447 * Setup for a possible bus error caused by SCSI controller
448 * switching out of DATA-IN/OUT before we're done with the
449 * current transfer.
450 */
451 nofault = &faultbuf;
452
453 if (setjmp(nofault)) {
454 nofault = (label_t *)0;
455 if ((dh->dh_flags & SBC_DH_DONE) == 0) {
456 count = (( (u_long)m68k_fault_addr
457 - (u_long)sc->sc_drq_addr));
458
459 if ((count < 0) || (count > dh->dh_len)) {
460 printf("%s: complete=0x%x (pending 0x%x)\n",
461 device_xname(ncr_sc->sc_dev), count,
462 dh->dh_len);
463 panic("something is wrong");
464 }
465
466 dh->dh_addr += count;
467 dh->dh_len -= count;
468 } else
469 count = 0;
470
471 #ifdef SBC_DEBUG
472 if (sbc_debug & SBC_DB_INTR)
473 printf("%s: drq /berr, complete=0x%x (pending 0x%x)\n",
474 device_xname(ncr_sc->sc_dev), count, dh->dh_len);
475 #endif
476 m68k_fault_addr = 0;
477
478 return;
479 }
480
481 if (dh->dh_flags & SBC_DH_OUT) { /* Data Out */
482 dcount = 0;
483
484 /*
485 * Get the source address aligned.
486 */
487 resid =
488 count = min(dh->dh_len, 4 - (((int)dh->dh_addr) & 0x3));
489 if (count && count < 4) {
490 drq = (volatile u_int8_t *)sc->sc_drq_addr;
491 data = (u_int8_t *)dh->dh_addr;
492
493 #define W1 *drq++ = *data++
494 while (count) {
495 W1; count--;
496 }
497 #undef W1
498 dh->dh_addr += resid;
499 dh->dh_len -= resid;
500 }
501
502 /*
503 * Start the transfer.
504 */
505 while (dh->dh_len) {
506 dcount = count = min(dh->dh_len, MAX_DMA_LEN);
507 long_drq = (volatile u_int32_t *)sc->sc_drq_addr;
508 long_data = (u_int32_t *)dh->dh_addr;
509
510 #define W4 *long_drq++ = *long_data++
511 while (count >= 64) {
512 W4; W4; W4; W4; W4; W4; W4; W4;
513 W4; W4; W4; W4; W4; W4; W4; W4; /* 64 */
514 count -= 64;
515 }
516 while (count >= 4) {
517 W4; count -= 4;
518 }
519 #undef W4
520 data = (u_int8_t *)long_data;
521 drq = (volatile u_int8_t *)long_drq;
522
523 #define W1 *drq++ = *data++
524 while (count) {
525 W1; count--;
526 }
527 #undef W1
528 dh->dh_len -= dcount;
529 dh->dh_addr += dcount;
530 }
531 dh->dh_flags |= SBC_DH_DONE;
532
533 /*
534 * XXX -- Read a byte from the SBC to trigger a /BERR.
535 * This seems to be necessary for us to notice that
536 * the target has disconnected. Ick. 06 jun 1996 (sr)
537 */
538 if (dcount >= MAX_DMA_LEN)
539 drq = (volatile u_int8_t *)sc->sc_drq_addr;
540 tmp = *drq;
541 } else { /* Data In */
542 /*
543 * Get the dest address aligned.
544 */
545 resid =
546 count = min(dh->dh_len, 4 - (((int)dh->dh_addr) & 0x3));
547 if (count && count < 4) {
548 data = (u_int8_t *)dh->dh_addr;
549 drq = (volatile u_int8_t *)sc->sc_drq_addr;
550
551 #define R1 *data++ = *drq++
552 while (count) {
553 R1; count--;
554 }
555 #undef R1
556 dh->dh_addr += resid;
557 dh->dh_len -= resid;
558 }
559
560 /*
561 * Start the transfer.
562 */
563 while (dh->dh_len) {
564 dcount = count = min(dh->dh_len, MAX_DMA_LEN);
565 long_data = (u_int32_t *)dh->dh_addr;
566 long_drq = (volatile u_int32_t *)sc->sc_drq_addr;
567
568 #define R4 *long_data++ = *long_drq++
569 while (count >= 64) {
570 R4; R4; R4; R4; R4; R4; R4; R4;
571 R4; R4; R4; R4; R4; R4; R4; R4; /* 64 */
572 count -= 64;
573 }
574 while (count >= 4) {
575 R4; count -= 4;
576 }
577 #undef R4
578 data = (u_int8_t *)long_data;
579 drq = (volatile u_int8_t *)long_drq;
580
581 #define R1 *data++ = *drq++
582 while (count) {
583 R1; count--;
584 }
585 #undef R1
586 dh->dh_len -= dcount;
587 dh->dh_addr += dcount;
588 }
589 dh->dh_flags |= SBC_DH_DONE;
590 }
591
592 /*
593 * OK. No bus error occurred above. Clear the nofault flag
594 * so we no longer short-circuit bus errors.
595 */
596 nofault = (label_t *)0;
597
598 #ifdef SBC_DEBUG
599 if (sbc_debug & (SBC_DB_REG | SBC_DB_INTR))
600 printf("%s: drq intr complete: csr=0x%x, bus_csr=0x%x\n",
601 device_xname(ncr_sc->sc_dev), *ncr_sc->sci_csr,
602 *ncr_sc->sci_bus_csr);
603 #endif
604 }
605
606 void
607 sbc_dma_alloc(struct ncr5380_softc *ncr_sc)
608 {
609 struct sbc_softc *sc = (struct sbc_softc *)ncr_sc;
610 struct sci_req *sr = ncr_sc->sc_current;
611 struct scsipi_xfer *xs = sr->sr_xs;
612 struct sbc_pdma_handle *dh;
613 int i, xlen;
614
615 #ifdef DIAGNOSTIC
616 if (sr->sr_dma_hand != NULL)
617 panic("sbc_dma_alloc: already have PDMA handle");
618 #endif
619
620 /* Polled transfers shouldn't allocate a PDMA handle. */
621 if (sr->sr_flags & SR_IMMED)
622 return;
623
624 xlen = ncr_sc->sc_datalen;
625
626 /* Make sure our caller checked sc_min_dma_len. */
627 if (xlen < MIN_DMA_LEN)
628 panic("sbc_dma_alloc: len=0x%x", xlen);
629
630 /*
631 * Find free PDMA handle. Guaranteed to find one since we
632 * have as many PDMA handles as the driver has processes.
633 * (instances?)
634 */
635 for (i = 0; i < SCI_OPENINGS; i++) {
636 if ((sc->sc_pdma[i].dh_flags & SBC_DH_BUSY) == 0)
637 goto found;
638 }
639 panic("sbc: no free PDMA handles");
640 found:
641 dh = &sc->sc_pdma[i];
642 dh->dh_flags = SBC_DH_BUSY;
643 dh->dh_addr = ncr_sc->sc_dataptr;
644 dh->dh_len = xlen;
645
646 /* Copy the 'write' flag for convenience. */
647 if (xs->xs_control & XS_CTL_DATA_OUT)
648 dh->dh_flags |= SBC_DH_OUT;
649
650 sr->sr_dma_hand = dh;
651 }
652
653 void
654 sbc_dma_free(struct ncr5380_softc *ncr_sc)
655 {
656 struct sci_req *sr = ncr_sc->sc_current;
657 struct sbc_pdma_handle *dh = sr->sr_dma_hand;
658
659 #ifdef DIAGNOSTIC
660 if (sr->sr_dma_hand == NULL)
661 panic("sbc_dma_free: no DMA handle");
662 #endif
663
664 if (ncr_sc->sc_state & NCR_DOINGDMA)
665 panic("sbc_dma_free: free while in progress");
666
667 if (dh->dh_flags & SBC_DH_BUSY) {
668 dh->dh_flags = 0;
669 dh->dh_addr = NULL;
670 dh->dh_len = 0;
671 }
672 sr->sr_dma_hand = NULL;
673 }
674
675 void
676 sbc_dma_poll(struct ncr5380_softc *ncr_sc)
677 {
678 struct sci_req *sr = ncr_sc->sc_current;
679
680 /*
681 * We shouldn't arrive here; if SR_IMMED is set, then
682 * dma_alloc() should have refused to allocate a handle
683 * for the transfer. This forces the polled PDMA code
684 * to handle the request...
685 */
686 #ifdef SBC_DEBUG
687 if (sbc_debug & SBC_DB_DMA)
688 printf("%s: lost DRQ interrupt?\n",
689 device_xname(ncr_sc->sc_dev));
690 #endif
691 sr->sr_flags |= SR_OVERDUE;
692 }
693
694 void
695 sbc_dma_setup(struct ncr5380_softc *ncr_sc)
696 {
697 /* Not needed; we don't have real DMA */
698 }
699
700 void
701 sbc_dma_start(struct ncr5380_softc *ncr_sc)
702 {
703 struct sbc_softc *sc = (struct sbc_softc *)ncr_sc;
704 struct sci_req *sr = ncr_sc->sc_current;
705 struct sbc_pdma_handle *dh = sr->sr_dma_hand;
706
707 /*
708 * Match bus phase, clear pending interrupts, set DMA mode, and
709 * assert data bus (for writing only), then start the transfer.
710 */
711 if (dh->dh_flags & SBC_DH_OUT) {
712 *ncr_sc->sci_tcmd = PHASE_DATA_OUT;
713 SCI_CLR_INTR(ncr_sc);
714 if (sc->sc_clrintr)
715 (*sc->sc_clrintr)(ncr_sc);
716 *ncr_sc->sci_mode |= SCI_MODE_DMA;
717 *ncr_sc->sci_icmd = SCI_ICMD_DATA;
718 *ncr_sc->sci_dma_send = 0;
719 } else {
720 *ncr_sc->sci_tcmd = PHASE_DATA_IN;
721 SCI_CLR_INTR(ncr_sc);
722 if (sc->sc_clrintr)
723 (*sc->sc_clrintr)(ncr_sc);
724 *ncr_sc->sci_mode |= SCI_MODE_DMA;
725 *ncr_sc->sci_icmd = 0;
726 *ncr_sc->sci_irecv = 0;
727 }
728 ncr_sc->sc_state |= NCR_DOINGDMA;
729
730 #ifdef SBC_DEBUG
731 if (sbc_debug & SBC_DB_DMA)
732 printf("%s: PDMA started, va=%p, len=0x%x\n",
733 device_xname(ncr_sc->sc_dev), dh->dh_addr, dh->dh_len);
734 #endif
735 }
736
737 void
738 sbc_dma_eop(struct ncr5380_softc *ncr_sc)
739 {
740 /* Not used; the EOP pin is wired high (GMFH, pp. 389-390) */
741 }
742
743 void
744 sbc_dma_stop(struct ncr5380_softc *ncr_sc)
745 {
746 struct sbc_softc *sc = (struct sbc_softc *)ncr_sc;
747 struct sci_req *sr = ncr_sc->sc_current;
748 struct sbc_pdma_handle *dh = sr->sr_dma_hand;
749 int ntrans;
750
751 if ((ncr_sc->sc_state & NCR_DOINGDMA) == 0) {
752 #ifdef SBC_DEBUG
753 if (sbc_debug & SBC_DB_DMA)
754 printf("%s: dma_stop: DMA not running\n",
755 device_xname(ncr_sc->sc_dev));
756 #endif
757 return;
758 }
759 ncr_sc->sc_state &= ~NCR_DOINGDMA;
760
761 if ((ncr_sc->sc_state & NCR_ABORTING) == 0) {
762 ntrans = ncr_sc->sc_datalen - dh->dh_len;
763
764 #ifdef SBC_DEBUG
765 if (sbc_debug & SBC_DB_DMA)
766 printf("%s: dma_stop: ntrans=0x%x\n",
767 device_xname(ncr_sc->sc_dev), ntrans);
768 #endif
769
770 if (ntrans > ncr_sc->sc_datalen)
771 panic("sbc_dma_stop: excess transfer");
772
773 /* Adjust data pointer */
774 ncr_sc->sc_dataptr += ntrans;
775 ncr_sc->sc_datalen -= ntrans;
776
777 /* Clear any pending interrupts. */
778 SCI_CLR_INTR(ncr_sc);
779 if (sc->sc_clrintr)
780 (*sc->sc_clrintr)(ncr_sc);
781 }
782
783 /* Put SBIC back into PIO mode. */
784 *ncr_sc->sci_mode &= ~SCI_MODE_DMA;
785 *ncr_sc->sci_icmd = 0;
786
787 #ifdef SBC_DEBUG
788 if (sbc_debug & SBC_DB_REG)
789 printf("%s: dma_stop: csr=0x%x, bus_csr=0x%x\n",
790 device_xname(ncr_sc->sc_dev), *ncr_sc->sci_csr,
791 *ncr_sc->sci_bus_csr);
792 #endif
793 }
794