xref: /netbsd-src/sys/dev/ic/lsi64854.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: lsi64854.c,v 1.11 2000/07/04 14:58:36 pk Exp $ */
2 
3 /*-
4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Paul Kranenburg.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/types.h>
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/errno.h>
44 #include <sys/device.h>
45 #include <sys/malloc.h>
46 
47 #include <machine/bus.h>
48 #include <machine/autoconf.h>
49 #include <machine/cpu.h>
50 
51 #include <dev/scsipi/scsi_all.h>
52 #include <dev/scsipi/scsipi_all.h>
53 #include <dev/scsipi/scsiconf.h>
54 
55 #include <dev/ic/lsi64854reg.h>
56 #include <dev/ic/lsi64854var.h>
57 
58 #include <dev/ic/ncr53c9xreg.h>
59 #include <dev/ic/ncr53c9xvar.h>
60 
61 void	lsi64854_reset	__P((struct lsi64854_softc *));
62 int	lsi64854_setup	__P((struct lsi64854_softc *, caddr_t *, size_t *,
63 			     int, size_t *));
64 int	lsi64854_setup_pp __P((struct lsi64854_softc *, caddr_t *, size_t *,
65 			     int, size_t *));
66 
67 #ifdef DEBUG
68 int lsi64854debug = 0;
69 #define DPRINTF(x) do { if (lsi64854debug != 0) printf x ; } while (0)
70 #else
71 #define DPRINTF(x)
72 #endif
73 
74 #define MAX_DMA_SZ	(16*1024*1024)
75 
76 /*
77  * Finish attaching this DMA device.
78  * Front-end must fill in these fields:
79  *	sc_bustag
80  *	sc_dmatag
81  *	sc_regs
82  *	sc_burst
83  *	sc_channel (one of SCSI, ENET, PP)
84  *	sc_client (one of SCSI, ENET, PP `soft_c' pointers)
85  */
86 void
87 lsi64854_attach(sc)
88 	struct lsi64854_softc *sc;
89 {
90 
91 	/* Indirect functions */
92 	switch (sc->sc_channel) {
93 	case L64854_CHANNEL_SCSI:
94 		sc->intr = lsi64854_scsi_intr;
95 		sc->setup = lsi64854_setup;
96 		break;
97 	case L64854_CHANNEL_ENET:
98 		sc->intr = lsi64854_enet_intr;
99 		break;
100 	case L64854_CHANNEL_PP:
101 		sc->setup = lsi64854_setup_pp;
102 		break;
103 	default:
104 		printf("%s: unknown channel\n", sc->sc_dev.dv_xname);
105 	}
106 	sc->reset = lsi64854_reset;
107 
108 	/* Allocate a dmamap */
109 	if (bus_dmamap_create(sc->sc_dmatag, MAX_DMA_SZ, 1, MAX_DMA_SZ,
110 			      0, BUS_DMA_WAITOK, &sc->sc_dmamap) != 0) {
111 		printf("%s: dma map create failed\n", sc->sc_dev.dv_xname);
112 		return;
113 	}
114 
115 	printf(": rev ");
116 	sc->sc_rev = L64854_GCSR(sc) & L64854_DEVID;
117 	switch (sc->sc_rev) {
118 	case DMAREV_0:
119 		printf("0");
120 		break;
121 	case DMAREV_ESC:
122 		printf("esc");
123 		break;
124 	case DMAREV_1:
125 		printf("1");
126 		break;
127 	case DMAREV_PLUS:
128 		printf("1+");
129 		break;
130 	case DMAREV_2:
131 		printf("2");
132 		break;
133 	default:
134 		printf("unknown (0x%x)", sc->sc_rev);
135 	}
136 	printf("\n");
137 
138 }
139 
140 #define DMAWAIT(SC, COND, MSG, DONTPANIC) do if (COND) {		\
141 	int count = 500000;						\
142 	while ((COND) && --count > 0) DELAY(1);				\
143 	if (count == 0) {						\
144 		printf("%s: line %d: CSR = 0x%lx\n", __FILE__, __LINE__, \
145 			(u_long)L64854_GCSR(SC));			\
146 		if (DONTPANIC)						\
147 			printf(MSG);					\
148 		else							\
149 			panic(MSG);					\
150 	}								\
151 } while (0)
152 
153 #define DMA_DRAIN(sc, dontpanic) do {					\
154 	u_int32_t csr;							\
155 	/*								\
156 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
157 	 *     and "drain" bits while it is still thinking about a	\
158 	 *     request.							\
159 	 * other revs: D_ESC_R_PEND bit reads as 0			\
160 	 */								\
161 	DMAWAIT(sc, L64854_GCSR(sc) & D_ESC_R_PEND, "R_PEND", dontpanic);\
162 	/*								\
163 	 * Select drain bit based on revision				\
164 	 * also clears errors and D_TC flag				\
165 	 */								\
166 	csr = L64854_GCSR(sc);					\
167 	if (sc->sc_rev == DMAREV_1 || sc->sc_rev == DMAREV_0)		\
168 		csr |= D_ESC_DRAIN;					\
169 	else								\
170 		csr |= L64854_INVALIDATE;				\
171 									\
172 	L64854_SCSR(sc,csr);						\
173 	/*								\
174 	 * Wait for draining to finish					\
175 	 *  rev0 & rev1 call this PACKCNT				\
176 	 */								\
177 	DMAWAIT(sc, L64854_GCSR(sc) & L64854_DRAINING, "DRAINING", dontpanic);\
178 } while(0)
179 
180 #define DMA_FLUSH(sc, dontpanic) do {					\
181 	u_int32_t csr;							\
182 	/*								\
183 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
184 	 *     and "drain" bits while it is still thinking about a	\
185 	 *     request.							\
186 	 * other revs: D_ESC_R_PEND bit reads as 0			\
187 	 */								\
188 	DMAWAIT(sc, L64854_GCSR(sc) & D_ESC_R_PEND, "R_PEND", dontpanic);\
189 	csr = L64854_GCSR(sc);					\
190 	csr &= ~(L64854_WRITE|L64854_EN_DMA); /* no-ops on ENET */	\
191 	csr |= L64854_INVALIDATE;					\
192 	L64854_SCSR(sc,csr);						\
193 } while(0)
194 
195 void
196 lsi64854_reset(sc)
197 	struct lsi64854_softc *sc;
198 {
199 	u_int32_t csr;
200 
201 	DMA_FLUSH(sc, 1);
202 	csr = L64854_GCSR(sc);
203 	csr |= L64854_RESET;		/* reset DMA */
204 	L64854_SCSR(sc, csr);
205 	DELAY(200);			/* > 10 Sbus clocks(?) */
206 
207 	/*DMAWAIT1(sc); why was this here? */
208 	csr = L64854_GCSR(sc);
209 	csr &= ~L64854_RESET;		/* de-assert reset line */
210 	L64854_SCSR(sc, csr);
211 	DELAY(5);			/* allow a few ticks to settle */
212 
213 	csr = L64854_GCSR(sc);
214 	csr |= L64854_INT_EN;		/* enable interrupts */
215 	if (sc->sc_rev > DMAREV_1 && sc->sc_channel == L64854_CHANNEL_SCSI)
216 		csr |= D_FASTER;
217 
218 	/* Set burst */
219 	switch (sc->sc_rev) {
220 	case DMAREV_2:
221 		csr &= ~L64854_BURST_SIZE;
222 		if (sc->sc_burst == 32) {
223 			csr |= L64854_BURST_32;
224 		} else if (sc->sc_burst == 16) {
225 			csr |= L64854_BURST_16;
226 		} else {
227 			csr |= L64854_BURST_0;
228 		}
229 		break;
230 	case DMAREV_ESC:
231 		csr |= D_ESC_AUTODRAIN;	/* Auto-drain */
232 		if (sc->sc_burst == 32) {
233 			csr &= ~D_ESC_BURST;
234 		} else
235 			csr |= D_ESC_BURST;
236 		break;
237 	default:
238 	}
239 	L64854_SCSR(sc, csr);
240 
241 	sc->sc_active = 0;
242 }
243 
244 
245 #define DMAMAX(a)	(MAX_DMA_SZ - ((a) & (MAX_DMA_SZ-1)))
246 /*
247  * setup a dma transfer
248  */
249 int
250 lsi64854_setup(sc, addr, len, datain, dmasize)
251 	struct lsi64854_softc *sc;
252 	caddr_t *addr;
253 	size_t *len;
254 	int datain;
255 	size_t *dmasize;	/* IN-OUT */
256 {
257 	u_int32_t csr;
258 
259 	DMA_FLUSH(sc, 0);
260 
261 #if 0
262 	DMACSR(sc) &= ~D_INT_EN;
263 #endif
264 	sc->sc_dmaaddr = addr;
265 	sc->sc_dmalen = len;
266 
267 	DPRINTF(("%s: start %ld@%p,%d\n", sc->sc_dev.dv_xname,
268 		(long)*sc->sc_dmalen, *sc->sc_dmaaddr, datain ? 1 : 0));
269 
270 	/*
271 	 * the rules say we cannot transfer more than the limit
272 	 * of this DMA chip (64k for old and 16Mb for new),
273 	 * and we cannot cross a 16Mb boundary.
274 	 */
275 	*dmasize = sc->sc_dmasize =
276 		min(*dmasize, DMAMAX((size_t) *sc->sc_dmaaddr));
277 
278 	DPRINTF(("dma_setup: dmasize = %ld\n", (long)sc->sc_dmasize));
279 
280 	/* Program the DMA address */
281 	if (sc->sc_dmasize) {
282 		sc->sc_dvmaaddr = *sc->sc_dmaaddr;
283 		if (bus_dmamap_load(sc->sc_dmatag, sc->sc_dmamap,
284 				*sc->sc_dmaaddr, sc->sc_dmasize,
285 				NULL /* kernel address */,
286 				BUS_DMA_NOWAIT))
287 			panic("%s: cannot allocate DVMA address",
288 			      sc->sc_dev.dv_xname);
289 		bus_dmamap_sync(sc->sc_dmatag, sc->sc_dmamap,
290 				(bus_addr_t)(u_long)sc->sc_dvmaaddr, sc->sc_dmasize,
291 				datain
292 					? BUS_DMASYNC_PREREAD
293 					: BUS_DMASYNC_PREWRITE);
294 		bus_space_write_4(sc->sc_bustag, sc->sc_regs, L64854_REG_ADDR,
295 				  sc->sc_dmamap->dm_segs[0].ds_addr);
296 	}
297 
298 	if (sc->sc_rev == DMAREV_ESC) {
299 		/* DMA ESC chip bug work-around */
300 		long bcnt = sc->sc_dmasize;
301 		long eaddr = bcnt + (long)*sc->sc_dmaaddr;
302 		if ((eaddr & PGOFSET) != 0)
303 			bcnt = roundup(bcnt, NBPG);
304 		bus_space_write_4(sc->sc_bustag, sc->sc_regs, L64854_REG_CNT,
305 				  bcnt);
306 	}
307 	/* Setup DMA control register */
308 	csr = L64854_GCSR(sc);
309 	if (datain)
310 		csr |= L64854_WRITE;
311 	else
312 		csr &= ~L64854_WRITE;
313 	csr |= L64854_INT_EN;
314 	L64854_SCSR(sc, csr);
315 
316 	return (0);
317 }
318 
319 /*
320  * Pseudo (chained) interrupt from the esp driver to kick the
321  * current running DMA transfer. Called from ncr53c9x_intr()
322  * for now.
323  *
324  * return 1 if it was a DMA continue.
325  */
326 int
327 lsi64854_scsi_intr(arg)
328 	void *arg;
329 {
330 	struct lsi64854_softc *sc = arg;
331 	struct ncr53c9x_softc *nsc = sc->sc_client;
332 	char bits[64];
333 	int trans, resid;
334 	u_int32_t csr;
335 
336 	csr = L64854_GCSR(sc);
337 
338 	DPRINTF(("%s: intr: addr 0x%x, csr %s\n", sc->sc_dev.dv_xname,
339 		 bus_space_read_4(sc->sc_bustag, sc->sc_regs, L64854_REG_ADDR),
340 		 bitmask_snprintf(csr, DDMACSR_BITS, bits, sizeof(bits))));
341 
342 	if (csr & (D_ERR_PEND|D_SLAVE_ERR)) {
343 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
344 			bitmask_snprintf(csr, DDMACSR_BITS, bits,sizeof(bits)));
345 		csr &= ~D_EN_DMA;	/* Stop DMA */
346 		/* Invalidate the queue; SLAVE_ERR bit is write-to-clear */
347 		csr |= D_INVALIDATE|D_SLAVE_ERR;
348 		L64854_SCSR(sc, csr);
349 		return (-1);
350 	}
351 
352 	/* This is an "assertion" :) */
353 	if (sc->sc_active == 0)
354 		panic("dmaintr: DMA wasn't active");
355 
356 	DMA_DRAIN(sc, 0);
357 
358 	/* DMA has stopped */
359 	csr &= ~D_EN_DMA;
360 	L64854_SCSR(sc, csr);
361 	sc->sc_active = 0;
362 
363 	if (sc->sc_dmasize == 0) {
364 		/* A "Transfer Pad" operation completed */
365 		DPRINTF(("dmaintr: discarded %d bytes (tcl=%d, tcm=%d)\n",
366 			NCR_READ_REG(nsc, NCR_TCL) |
367 				(NCR_READ_REG(nsc, NCR_TCM) << 8),
368 			NCR_READ_REG(nsc, NCR_TCL),
369 			NCR_READ_REG(nsc, NCR_TCM)));
370 		return 0;
371 	}
372 
373 	resid = 0;
374 	/*
375 	 * If a transfer onto the SCSI bus gets interrupted by the device
376 	 * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
377 	 * as residual since the NCR53C9X counter registers get decremented
378 	 * as bytes are clocked into the FIFO.
379 	 */
380 	if (!(csr & D_WRITE) &&
381 	    (resid = (NCR_READ_REG(nsc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
382 		DPRINTF(("dmaintr: empty esp FIFO of %d ", resid));
383 	}
384 
385 	if ((nsc->sc_espstat & NCRSTAT_TC) == 0) {
386 		/*
387 		 * `Terminal count' is off, so read the residue
388 		 * out of the NCR53C9X counter registers.
389 		 */
390 		resid += (NCR_READ_REG(nsc, NCR_TCL) |
391 			  (NCR_READ_REG(nsc, NCR_TCM) << 8) |
392 			   ((nsc->sc_cfg2 & NCRCFG2_FE)
393 				? (NCR_READ_REG(nsc, NCR_TCH) << 16)
394 				: 0));
395 
396 		if (resid == 0 && sc->sc_dmasize == 65536 &&
397 		    (nsc->sc_cfg2 & NCRCFG2_FE) == 0)
398 			/* A transfer of 64K is encoded as `TCL=TCM=0' */
399 			resid = 65536;
400 	}
401 
402 	trans = sc->sc_dmasize - resid;
403 	if (trans < 0) {			/* transferred < 0 ? */
404 #if 0
405 		/*
406 		 * This situation can happen in perfectly normal operation
407 		 * if the ESP is reselected while using DMA to select
408 		 * another target.  As such, don't print the warning.
409 		 */
410 		printf("%s: xfer (%d) > req (%d)\n",
411 		    sc->sc_dev.dv_xname, trans, sc->sc_dmasize);
412 #endif
413 		trans = sc->sc_dmasize;
414 	}
415 
416 	DPRINTF(("dmaintr: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n",
417 		NCR_READ_REG(nsc, NCR_TCL),
418 		NCR_READ_REG(nsc, NCR_TCM),
419 		(nsc->sc_cfg2 & NCRCFG2_FE)
420 			? NCR_READ_REG(nsc, NCR_TCH) : 0,
421 		trans, resid));
422 
423 	if (sc->sc_dmamap->dm_nsegs > 0) {
424 		bus_dmamap_sync(sc->sc_dmatag, sc->sc_dmamap,
425 				(bus_addr_t)(u_long)sc->sc_dvmaaddr, sc->sc_dmasize,
426 				(csr & D_WRITE) != 0
427 					? BUS_DMASYNC_POSTREAD
428 					: BUS_DMASYNC_POSTWRITE);
429 		bus_dmamap_unload(sc->sc_dmatag, sc->sc_dmamap);
430 	}
431 
432 	*sc->sc_dmalen -= trans;
433 	*sc->sc_dmaaddr += trans;
434 
435 #if 0	/* this is not normal operation just yet */
436 	if (*sc->sc_dmalen == 0 ||
437 	    nsc->sc_phase != nsc->sc_prevphase)
438 		return 0;
439 
440 	/* and again */
441 	dma_start(sc, sc->sc_dmaaddr, sc->sc_dmalen, DMACSR(sc) & D_WRITE);
442 	return 1;
443 #endif
444 	return 0;
445 }
446 
447 /*
448  * Pseudo (chained) interrupt to le driver to handle DMA errors.
449  */
450 int
451 lsi64854_enet_intr(arg)
452 	void	*arg;
453 {
454 	struct lsi64854_softc *sc = arg;
455 	char bits[64];
456 	u_int32_t csr;
457 	static int dodrain = 0;
458 	int rv;
459 
460 	csr = L64854_GCSR(sc);
461 
462 	/* If the DMA logic shows an interrupt, claim it */
463 	rv = ((csr & E_INT_PEND) != 0) ? 1 : 0;
464 
465 	if (csr & (E_ERR_PEND|E_SLAVE_ERR)) {
466 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
467 			bitmask_snprintf(csr, EDMACSR_BITS, bits,sizeof(bits)));
468 		csr &= ~L64854_EN_DMA;	/* Stop DMA */
469 		/* Invalidate the queue; SLAVE_ERR bit is write-to-clear */
470 		csr |= E_INVALIDATE|E_SLAVE_ERR;
471 		L64854_SCSR(sc, csr);
472 		DMA_RESET(sc);
473 		dodrain = 1;
474 		return (1);
475 	}
476 
477 	if (dodrain) {	/* XXX - is this necessary with D_DSBL_WRINVAL on? */
478 		int i = 10;
479 		csr |= E_DRAIN;
480 		L64854_SCSR(sc, csr);
481 		while (i-- > 0 && (L64854_GCSR(sc) & D_DRAINING))
482 			delay(1);
483 	}
484 
485 	return (rv | (*sc->sc_intrchain)(sc->sc_intrchainarg));
486 }
487 
488 /*
489  * setup a dma transfer
490  */
491 int
492 lsi64854_setup_pp(sc, addr, len, datain, dmasize)
493 	struct lsi64854_softc *sc;
494 	caddr_t *addr;
495 	size_t *len;
496 	int datain;
497 	size_t *dmasize;	/* IN-OUT */
498 {
499 	u_int32_t csr;
500 
501 	DMA_FLUSH(sc, 0);
502 
503 	sc->sc_dmaaddr = addr;
504 	sc->sc_dmalen = len;
505 
506 	DPRINTF(("%s: start %ld@%p,%d\n", sc->sc_dev.dv_xname,
507 		(long)*sc->sc_dmalen, *sc->sc_dmaaddr, datain ? 1 : 0));
508 
509 	/*
510 	 * the rules say we cannot transfer more than the limit
511 	 * of this DMA chip (64k for old and 16Mb for new),
512 	 * and we cannot cross a 16Mb boundary.
513 	 */
514 	*dmasize = sc->sc_dmasize =
515 		min(*dmasize, DMAMAX((size_t) *sc->sc_dmaaddr));
516 
517 	DPRINTF(("dma_setup: dmasize = %ld\n", (long)sc->sc_dmasize));
518 
519 	/* Program the DMA address */
520 	if (sc->sc_dmasize) {
521 		sc->sc_dvmaaddr = *sc->sc_dmaaddr;
522 		if (bus_dmamap_load(sc->sc_dmatag, sc->sc_dmamap,
523 				*sc->sc_dmaaddr, sc->sc_dmasize,
524 				NULL /* kernel address */,
525 				BUS_DMA_NOWAIT))
526 			panic("%s: cannot allocate DVMA address",
527 			      sc->sc_dev.dv_xname);
528 		bus_dmamap_sync(sc->sc_dmatag, sc->sc_dmamap,
529 				(bus_addr_t)(u_long)sc->sc_dvmaaddr, sc->sc_dmasize,
530 				datain
531 					? BUS_DMASYNC_PREREAD
532 					: BUS_DMASYNC_PREWRITE);
533 		bus_space_write_4(sc->sc_bustag, sc->sc_regs, L64854_REG_ADDR,
534 				  sc->sc_dmamap->dm_segs[0].ds_addr);
535 
536 		bus_space_write_4(sc->sc_bustag, sc->sc_regs, L64854_REG_CNT,
537 				  sc->sc_dmasize);
538 	}
539 
540 	/* Setup DMA control register */
541 	csr = L64854_GCSR(sc);
542 #if 0
543 	/* This bit is read-only in PP csr register */
544 	if (datain)
545 		csr |= L64854_WRITE;
546 	else
547 		csr &= ~L64854_WRITE;
548 #endif
549 	csr |= L64854_INT_EN;
550 	L64854_SCSR(sc, csr);
551 
552 	return (0);
553 }
554 /*
555  * Parallel port DMA interrupt.
556  */
557 int
558 lsi64854_pp_intr(arg)
559 	void *arg;
560 {
561 	struct lsi64854_softc *sc = arg;
562 	char bits[64];
563 	int ret, trans, resid = 0;
564 	u_int32_t csr;
565 
566 	csr = L64854_GCSR(sc);
567 
568 	DPRINTF(("%s: intr: addr 0x%x, csr %s\n", sc->sc_dev.dv_xname,
569 		 bus_space_read_4(sc->sc_bustag, sc->sc_regs, L64854_REG_ADDR),
570 		 bitmask_snprintf(csr, PDMACSR_BITS, bits, sizeof(bits))));
571 
572 	if (csr & (P_ERR_PEND|P_SLAVE_ERR)) {
573 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
574 			bitmask_snprintf(csr, PDMACSR_BITS, bits,sizeof(bits)));
575 		csr &= ~P_EN_DMA;	/* Stop DMA */
576 		/* Invalidate the queue; SLAVE_ERR bit is write-to-clear */
577 		csr |= P_INVALIDATE|P_SLAVE_ERR;
578 		L64854_SCSR(sc, csr);
579 		return (1);
580 	}
581 
582 	ret = (csr & P_INT_PEND) != 0;
583 
584 	if (sc->sc_active != 0) {
585 		DMA_DRAIN(sc, 0);
586 		resid = bus_space_read_4(sc->sc_bustag, sc->sc_regs,
587 					 L64854_REG_CNT);
588 	}
589 
590 	/* DMA has stopped */
591 	csr &= ~D_EN_DMA;
592 	L64854_SCSR(sc, csr);
593 	sc->sc_active = 0;
594 
595 	trans = sc->sc_dmasize - resid;
596 	if (trans < 0) {			/* transferred < 0 ? */
597 		trans = sc->sc_dmasize;
598 	}
599 	*sc->sc_dmalen -= trans;
600 	*sc->sc_dmaaddr += trans;
601 
602 	if (sc->sc_dmamap->dm_nsegs > 0) {
603 		bus_dmamap_sync(sc->sc_dmatag, sc->sc_dmamap,
604 				(bus_addr_t)(u_long)sc->sc_dvmaaddr, sc->sc_dmasize,
605 				(csr & D_WRITE) != 0
606 					? BUS_DMASYNC_POSTREAD
607 					: BUS_DMASYNC_POSTWRITE);
608 		bus_dmamap_unload(sc->sc_dmatag, sc->sc_dmamap);
609 	}
610 
611 	ret |= (*sc->sc_intrchain)(sc->sc_intrchainarg);
612 	return (ret != 0);
613 }
614