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intio_dmac.c revision 1.37
      1 /*	$NetBSD: intio_dmac.c,v 1.37 2017/08/11 07:30:01 isaki Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Minoura Makoto.
      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  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Hitachi HD63450 (= Motorola MC68450) DMAC driver for x68k.
     34  */
     35 
     36 #include "opt_m68k_arch.h"
     37 
     38 #include <sys/cdefs.h>
     39 __KERNEL_RCSID(0, "$NetBSD: intio_dmac.c,v 1.37 2017/08/11 07:30:01 isaki Exp $");
     40 
     41 #include <sys/param.h>
     42 #include <sys/systm.h>
     43 #include <sys/device.h>
     44 #include <uvm/uvm_extern.h>
     45 
     46 #include <machine/bus.h>
     47 #include <machine/cpu.h>
     48 #include <machine/frame.h>
     49 
     50 #include <arch/x68k/dev/intiovar.h>
     51 #include <arch/x68k/dev/dmacvar.h>
     52 
     53 #ifdef DMAC_DEBUG
     54 #define DPRINTF(n,x)	if (dmacdebug>((n)&0x0f)) printf x
     55 #define DDUMPREGS(n,x)	if (dmacdebug>((n)&0x0f)) {printf x; dmac_dump_regs();}
     56 int dmacdebug = 0;
     57 #else
     58 #define DPRINTF(n,x)
     59 #define DDUMPREGS(n,x)
     60 #endif
     61 
     62 static void dmac_init_channels(struct dmac_softc *);
     63 #ifdef DMAC_ARRAYCHAIN
     64 static int dmac_program_arraychain(device_t, struct dmac_dma_xfer *,
     65 	u_int, u_int);
     66 #endif
     67 static int dmac_done(void *);
     68 static int dmac_error(void *);
     69 
     70 #ifdef DMAC_DEBUG
     71 static int dmac_dump_regs(void);
     72 #endif
     73 
     74 /*
     75  * autoconf stuff
     76  */
     77 static int dmac_match(device_t, cfdata_t, void *);
     78 static void dmac_attach(device_t, device_t, void *);
     79 
     80 CFATTACH_DECL_NEW(dmac, sizeof(struct dmac_softc),
     81     dmac_match, dmac_attach, NULL, NULL);
     82 
     83 static int dmac_attached;
     84 
     85 static int
     86 dmac_match(device_t parent, cfdata_t cf, void *aux)
     87 {
     88 	struct intio_attach_args *ia = aux;
     89 
     90 	if (strcmp(ia->ia_name, "dmac") != 0)
     91 		return (0);
     92 	if (dmac_attached)
     93 		return (0);
     94 
     95 	if (ia->ia_addr == INTIOCF_ADDR_DEFAULT)
     96 		ia->ia_addr = DMAC_ADDR;
     97 
     98 	/* fixed address */
     99 	if (ia->ia_addr != DMAC_ADDR)
    100 		return (0);
    101 	if (ia->ia_intr != INTIOCF_INTR_DEFAULT)
    102 		return (0);
    103 
    104 	return 1;
    105 }
    106 
    107 static void
    108 dmac_attach(device_t parent, device_t self, void *aux)
    109 {
    110 	struct dmac_softc *sc = device_private(self);
    111 	struct intio_attach_args *ia = aux;
    112 	struct intio_softc *intio;
    113 	int r __diagused;
    114 
    115 	sc->sc_dev = self;
    116 	dmac_attached = 1;
    117 
    118 	ia->ia_size = DMAC_CHAN_SIZE * DMAC_NCHAN;
    119 	r = intio_map_allocate_region(parent, ia, INTIO_MAP_ALLOCATE);
    120 #ifdef DIAGNOSTIC
    121 	if (r)
    122 		panic("IO map for DMAC corruption??");
    123 #endif
    124 
    125 	intio = device_private(parent);
    126 	intio->sc_dmac = self;
    127 	sc->sc_bst = ia->ia_bst;
    128 	bus_space_map(sc->sc_bst, ia->ia_addr, ia->ia_size, 0, &sc->sc_bht);
    129 	dmac_init_channels(sc);
    130 
    131 	aprint_normal(": HD63450 DMAC\n");
    132 	aprint_normal_dev(self, "4 channels available.\n");
    133 }
    134 
    135 static void
    136 dmac_init_channels(struct dmac_softc *sc)
    137 {
    138 	int i;
    139 
    140 	DPRINTF(3, ("dmac_init_channels\n"));
    141 	for (i=0; i<DMAC_NCHAN; i++) {
    142 		sc->sc_channels[i].ch_channel = i;
    143 		sc->sc_channels[i].ch_name[0] = 0;
    144 		sc->sc_channels[i].ch_softc = sc;
    145 		bus_space_subregion(sc->sc_bst, sc->sc_bht,
    146 				    DMAC_CHAN_SIZE*i, DMAC_CHAN_SIZE,
    147 				    &sc->sc_channels[i].ch_bht);
    148 		sc->sc_channels[i].ch_xfer.dx_dmamap = 0;
    149 		/* reset the status register */
    150 		bus_space_write_1(sc->sc_bst, sc->sc_channels[i].ch_bht,
    151 				  DMAC_REG_CSR, 0xff);
    152 	}
    153 
    154 	return;
    155 }
    156 
    157 
    158 /*
    159  * Channel initialization/deinitialization per user device.
    160  */
    161 struct dmac_channel_stat *
    162 dmac_alloc_channel(device_t self, int ch, const char *name,
    163     int normalv, dmac_intr_handler_t normal, void *normalarg,
    164     int errorv,  dmac_intr_handler_t error,  void *errorarg,
    165     uint8_t dcr, uint8_t ocr)
    166 {
    167 	struct intio_softc *intio = device_private(self);
    168 	struct dmac_softc *dmac = device_private(intio->sc_dmac);
    169 	struct dmac_channel_stat *chan = &dmac->sc_channels[ch];
    170 #ifdef DMAC_ARRAYCHAIN
    171 	int r, dummy;
    172 #endif
    173 
    174 	aprint_normal_dev(dmac->sc_dev, "allocating ch %d for %s.\n",
    175 		ch, name);
    176 	DPRINTF(3, ("dmamap=%p\n", (void *)chan->ch_xfer.dx_dmamap));
    177 #ifdef DIAGNOSTIC
    178 	if (ch < 0 || ch >= DMAC_NCHAN)
    179 		panic("Invalid DMAC channel.");
    180 	if (chan->ch_name[0])
    181 		panic("DMAC: channel in use.");
    182 	if (strlen(name) > 8)
    183 	  	panic("DMAC: wrong user name.");
    184 #endif
    185 
    186 #ifdef DMAC_ARRAYCHAIN
    187 	/* allocate the DMAC arraychaining map */
    188 	r = bus_dmamem_alloc(intio->sc_dmat,
    189 			     sizeof(struct dmac_sg_array) * DMAC_MAPSIZE,
    190 			     4, 0, &chan->ch_seg[0], 1, &dummy,
    191 			     BUS_DMA_NOWAIT);
    192 	if (r)
    193 		panic("DMAC: cannot alloc DMA safe memory");
    194 	r = bus_dmamem_map(intio->sc_dmat,
    195 			   &chan->ch_seg[0], 1,
    196 			   sizeof(struct dmac_sg_array) * DMAC_MAPSIZE,
    197 			   (void **) &chan->ch_map,
    198 			   BUS_DMA_NOWAIT|BUS_DMA_COHERENT);
    199 	if (r)
    200 		panic("DMAC: cannot map DMA safe memory");
    201 #endif
    202 
    203 	/* fill the channel status structure by the default values. */
    204 	strcpy(chan->ch_name, name);
    205 	chan->ch_dcr = dcr;
    206 	chan->ch_ocr = ocr;
    207 	chan->ch_normalv = normalv;
    208 	chan->ch_errorv = errorv;
    209 	chan->ch_normal = normal;
    210 	chan->ch_error = error;
    211 	chan->ch_normalarg = normalarg;
    212 	chan->ch_errorarg = errorarg;
    213 	chan->ch_xfer.dx_dmamap = 0;
    214 
    215 	/* setup the device-specific registers */
    216 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    217 	bus_space_write_1(dmac->sc_bst, chan->ch_bht,
    218 			   DMAC_REG_DCR, chan->ch_dcr);
    219 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CPR, 0);
    220 	/* OCR will be written at dmac_load_xfer() */
    221 
    222 	/*
    223 	 * X68k physical user space is a subset of the kernel space;
    224 	 * the memory is always included in the physical user space,
    225 	 * while the device is not.
    226 	 */
    227 	bus_space_write_1(dmac->sc_bst, chan->ch_bht,
    228 			   DMAC_REG_BFCR, DMAC_FC_USER_DATA);
    229 	bus_space_write_1(dmac->sc_bst, chan->ch_bht,
    230 			   DMAC_REG_MFCR, DMAC_FC_USER_DATA);
    231 	bus_space_write_1(dmac->sc_bst, chan->ch_bht,
    232 			   DMAC_REG_DFCR, DMAC_FC_KERNEL_DATA);
    233 
    234 	/* setup the interrupt handlers */
    235 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_NIVR, normalv);
    236 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_EIVR, errorv);
    237 
    238 	intio_intr_establish_ext(normalv, name, "dma", dmac_done, chan);
    239 	intio_intr_establish_ext(errorv, name, "dmaerr", dmac_error, chan);
    240 
    241 	return chan;
    242 }
    243 
    244 int
    245 dmac_free_channel(device_t self, int ch, void *channel)
    246 {
    247 	struct intio_softc *intio = device_private(self);
    248 	struct dmac_softc *dmac = device_private(intio->sc_dmac);
    249 	struct dmac_channel_stat *chan = &dmac->sc_channels[ch];
    250 
    251 	DPRINTF(3, ("dmac_free_channel, %d\n", ch));
    252 	DPRINTF(3, ("dmamap=%p\n", (void *)chan->ch_xfer.dx_dmamap));
    253 	if (chan != channel)
    254 		return -1;
    255 	if (ch != chan->ch_channel)
    256 		return -1;
    257 
    258 #ifdef DMAC_ARRAYCHAIN
    259 	bus_dmamem_unmap(intio->sc_dmat, (void *)chan->ch_map,
    260 			 sizeof(struct dmac_sg_array) * DMAC_MAPSIZE);
    261 	bus_dmamem_free(intio->sc_dmat, &chan->ch_seg[0], 1);
    262 #endif
    263 	chan->ch_name[0] = 0;
    264 	intio_intr_disestablish(chan->ch_normalv, channel);
    265 	intio_intr_disestablish(chan->ch_errorv, channel);
    266 
    267 	return 0;
    268 }
    269 
    270 /*
    271  * Initialization / deinitialization per transfer.
    272  */
    273 struct dmac_dma_xfer *
    274 dmac_alloc_xfer(struct dmac_channel_stat *chan, bus_dma_tag_t dmat,
    275     bus_dmamap_t dmamap)
    276 {
    277 	struct dmac_dma_xfer *xf = &chan->ch_xfer;
    278 
    279 	DPRINTF(3, ("dmac_alloc_xfer\n"));
    280 	xf->dx_channel = chan;
    281 	xf->dx_dmamap = dmamap;
    282 	xf->dx_tag = dmat;
    283 #ifdef DMAC_ARRAYCHAIN
    284 	xf->dx_array = chan->ch_map;
    285 	xf->dx_done = 0;
    286 #endif
    287 	return xf;
    288 }
    289 
    290 int
    291 dmac_load_xfer(struct dmac_softc *dmac, struct dmac_dma_xfer *xf)
    292 {
    293 	struct dmac_channel_stat *chan = xf->dx_channel;
    294 
    295 	DPRINTF(3, ("dmac_load_xfer\n"));
    296 
    297 	xf->dx_ocr &= ~DMAC_OCR_CHAIN_MASK;
    298 	if (xf->dx_dmamap->dm_nsegs == 1)
    299 		xf->dx_ocr |= DMAC_OCR_CHAIN_DISABLED;
    300 	else {
    301 		xf->dx_ocr |= DMAC_OCR_CHAIN_ARRAY;
    302 	}
    303 
    304 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    305 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_SCR, xf->dx_scr);
    306 	bus_space_write_1(dmac->sc_bst, chan->ch_bht,
    307 			  DMAC_REG_OCR, (xf->dx_ocr | chan->ch_ocr));
    308 	bus_space_write_4(dmac->sc_bst, chan->ch_bht,
    309 			  DMAC_REG_DAR, (int) xf->dx_device);
    310 
    311 	return 0;
    312 }
    313 
    314 struct dmac_dma_xfer *
    315 dmac_prepare_xfer(struct dmac_channel_stat *chan, bus_dma_tag_t dmat,
    316     bus_dmamap_t dmamap, int dir, int scr, void *dar)
    317 {
    318 	struct dmac_dma_xfer *xf;
    319 	struct dmac_softc *dmac = chan->ch_softc;
    320 
    321 	xf = dmac_alloc_xfer(chan, dmat, dmamap);
    322 
    323 	xf->dx_ocr = dir & DMAC_OCR_DIR_MASK;
    324 	xf->dx_scr = scr & (DMAC_SCR_MAC_MASK|DMAC_SCR_DAC_MASK);
    325 	xf->dx_device = dar;
    326 
    327 	dmac_load_xfer(dmac, xf);
    328 
    329 	return xf;
    330 }
    331 
    332 #ifdef DMAC_DEBUG
    333 static struct dmac_channel_stat *debugchan = 0;
    334 #endif
    335 
    336 /*
    337  * Do the actual transfer.
    338  */
    339 int
    340 dmac_start_xfer(struct dmac_softc *dmac, struct dmac_dma_xfer *xf)
    341 {
    342 	return dmac_start_xfer_offset(dmac, xf, 0, 0);
    343 }
    344 
    345 int
    346 dmac_start_xfer_offset(struct dmac_softc *dmac, struct dmac_dma_xfer *xf,
    347     u_int offset, u_int size)
    348 {
    349 	struct dmac_channel_stat *chan = xf->dx_channel;
    350 	struct x68k_bus_dmamap *dmamap = xf->dx_dmamap;
    351 	int go = DMAC_CCR_STR|DMAC_CCR_INT;
    352 	bus_addr_t paddr;
    353 	uint8_t csr;
    354 #ifdef DMAC_ARRAYCHAIN
    355 	int c;
    356 #endif
    357 
    358 	DPRINTF(3, ("dmac_start_xfer\n"));
    359 #ifdef DMAC_DEBUG
    360 	debugchan=chan;
    361 #endif
    362 
    363 	if (size == 0) {
    364 #ifdef DIAGNOSTIC
    365 		if (offset != 0)
    366 			panic("dmac_start_xfer_offset: invalid offset %x",
    367 			       offset);
    368 #endif
    369 		size = dmamap->dm_mapsize;
    370 	}
    371 
    372 #ifdef DMAC_ARRAYCHAIN
    373 #ifdef DIAGNOSTIC
    374 	if (xf->dx_done)
    375 		panic("dmac_start_xfer: DMA transfer in progress");
    376 #endif
    377 #endif
    378 	DPRINTF(3, ("First program:\n"));
    379 #ifdef DIAGNOSTIC
    380 	if ((offset >= dmamap->dm_mapsize) ||
    381 	    (offset + size > dmamap->dm_mapsize))
    382 		panic("dmac_start_xfer_offset: invalid offset: "
    383 			"offset=%d, size=%d, mapsize=%ld",
    384 		       offset, size, dmamap->dm_mapsize);
    385 #endif
    386 	/* program DMAC in single block mode or array chainning mode */
    387 	if (dmamap->dm_nsegs == 1) {
    388 		DPRINTF(3, ("single block mode\n"));
    389 #ifdef DIAGNOSTIC
    390 		if (dmamap->dm_mapsize != dmamap->dm_segs[0].ds_len)
    391 			panic("dmac_start_xfer_offset: dmamap curruption");
    392 #endif
    393 		paddr = dmamap->dm_segs[0].ds_addr + offset;
    394 		csr = bus_space_read_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CSR);
    395 		if ((csr & DMAC_CSR_ACT) != 0) {
    396 			/* Use 'Continue Mode' */
    397 			bus_space_write_4(dmac->sc_bst, chan->ch_bht,
    398 			    DMAC_REG_BAR, paddr);
    399 			bus_space_write_2(dmac->sc_bst, chan->ch_bht,
    400 			    DMAC_REG_BTCR, (int) size);
    401 			go |=  DMAC_CCR_CNT;
    402 			go &= ~DMAC_CCR_STR;
    403 		} else {
    404 			bus_space_write_4(dmac->sc_bst, chan->ch_bht,
    405 					  DMAC_REG_MAR, paddr);
    406 			bus_space_write_2(dmac->sc_bst, chan->ch_bht,
    407 					  DMAC_REG_MTCR, (int) size);
    408 		}
    409 #ifdef DMAC_ARRAYCHAIN
    410 		xf->dx_done = 1;
    411 #endif
    412 	} else {
    413 #ifdef DMAC_ARRAYCHAIN
    414 		c = dmac_program_arraychain(self, xf, offset, size);
    415 		bus_space_write_4(dmac->sc_bst, chan->ch_bht,
    416 				  DMAC_REG_BAR, (int) chan->ch_seg[0].ds_addr);
    417 		bus_space_write_2(dmac->sc_bst, chan->ch_bht,
    418 				  DMAC_REG_BTCR, c);
    419 #else
    420 		panic("DMAC: unexpected use of arraychaining mode");
    421 #endif
    422 	}
    423 
    424 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    425 
    426 	/* START!! */
    427 	DDUMPREGS(3, ("first start\n"));
    428 
    429 #ifdef DMAC_ARRAYCHAIN
    430 #if defined(M68040) || defined(M68060)
    431 	/* flush data cache for the map */
    432 	if (dmamap->dm_nsegs != 1 && mmutype == MMU_68040)
    433 		dma_cachectl((void *) xf->dx_array,
    434 			     sizeof(struct dmac_sg_array) * c);
    435 #endif
    436 #endif
    437 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CCR, go);
    438 
    439 	return 0;
    440 }
    441 
    442 #ifdef DMAC_ARRAYCHAIN
    443 static int
    444 dmac_program_arraychain(device_t self, struct dmac_dma_xfer *xf,
    445     u_int offset, u_int size)
    446 {
    447 	struct dmac_channel_stat *chan = xf->dx_channel;
    448 	int ch = chan->ch_channel;
    449 	struct x68k_bus_dmamap *map = xf->dx_dmamap;
    450 	int i, j;
    451 
    452 	/* XXX not yet!! */
    453 	if (offset != 0 || size != map->dm_mapsize)
    454 		panic("dmac_program_arraychain: unsupported offset/size");
    455 
    456 	DPRINTF(3, ("dmac_program_arraychain\n"));
    457 	for (i=0, j=xf->dx_done; i<DMAC_MAPSIZE && j<map->dm_nsegs;
    458 	     i++, j++) {
    459 		xf->dx_array[i].da_addr = map->dm_segs[j].ds_addr;
    460 #ifdef DIAGNOSTIC
    461 		if (map->dm_segs[j].ds_len > DMAC_MAXSEGSZ)
    462 			panic("dmac_program_arraychain: wrong map: %ld",
    463 			       map->dm_segs[j].ds_len);
    464 #endif
    465 		xf->dx_array[i].da_count = map->dm_segs[j].ds_len;
    466 	}
    467 	xf->dx_done = j;
    468 
    469 	return i;
    470 }
    471 #endif
    472 
    473 /*
    474  * interrupt handlers.
    475  */
    476 static int
    477 dmac_done(void *arg)
    478 {
    479 	struct dmac_channel_stat *chan = arg;
    480 	struct dmac_softc *sc = chan->ch_softc;
    481 #ifdef DMAC_ARRAYCHAIN
    482 	struct dmac_dma_xfer *xf = &chan->ch_xfer;
    483 	struct x68k_bus_dmamap *map = xf->dx_dmamap;
    484 	int c;
    485 #endif
    486 
    487 	DPRINTF(3, ("dmac_done\n"));
    488 
    489 	bus_space_write_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    490 
    491 #ifdef DMAC_ARRAYCHAIN
    492 	if (xf->dx_done == map->dm_nsegs) {
    493 		xf->dx_done = 0;
    494 #endif
    495 		/* Done */
    496 		return (*chan->ch_normal)(chan->ch_normalarg);
    497 #ifdef DMAC_ARRAYCHAIN
    498 	}
    499 #endif
    500 
    501 #ifdef DMAC_ARRAYCHAIN
    502 	/* Continue transfer */
    503 	DPRINTF(3, ("reprograming\n"));
    504 	c = dmac_program_arraychain(sc->sc_dev, xf, 0, map->dm_mapsize);
    505 
    506 	bus_space_write_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    507 	bus_space_write_4(sc->sc_bst, chan->ch_bht,
    508 			  DMAC_REG_BAR, (int) chan->ch_map);
    509 	bus_space_write_4(sc->sc_bst, chan->ch_bht,
    510 			  DMAC_REG_DAR, (int) xf->dx_device);
    511 	bus_space_write_2(sc->sc_bst, chan->ch_bht, DMAC_REG_BTCR, c);
    512 
    513 	/* START!! */
    514 	DDUMPREGS(3, ("restart\n"));
    515 	bus_space_write_1(sc->sc_bst, chan->ch_bht,
    516 			  DMAC_REG_CCR, DMAC_CCR_STR|DMAC_CCR_INT);
    517 
    518 	return 1;
    519 #endif
    520 }
    521 
    522 static int
    523 dmac_error(void *arg)
    524 {
    525 	struct dmac_channel_stat *chan = arg;
    526 	struct dmac_softc *sc = chan->ch_softc;
    527 	uint8_t csr, cer;
    528 
    529 	csr = bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CSR);
    530 	cer = bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CER);
    531 
    532 #ifndef DMAC_DEBUG
    533 	/* Software abort (CER=0x11) could happen on normal xfer termination */
    534 	if (cer != 0x11)
    535 #endif
    536 	{
    537 		printf("DMAC transfer error CSR=%02x, CER=%02x\n", csr, cer);
    538 	}
    539 	DDUMPREGS(3, ("registers were:\n"));
    540 
    541 	/* Clear the status bits */
    542 	bus_space_write_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    543 
    544 #ifdef DMAC_ARRAYCHAIN
    545 	chan->ch_xfer.dx_done = 0;
    546 #endif
    547 
    548 	return (*chan->ch_error)(chan->ch_errorarg);
    549 }
    550 
    551 int
    552 dmac_abort_xfer(struct dmac_softc *dmac, struct dmac_dma_xfer *xf)
    553 {
    554 	struct dmac_channel_stat *chan = xf->dx_channel;
    555 
    556 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CCR,
    557 			  DMAC_CCR_INT | DMAC_CCR_SAB);
    558 	bus_space_write_1(dmac->sc_bst, chan->ch_bht, DMAC_REG_CSR, 0xff);
    559 
    560 	return 0;
    561 }
    562 
    563 #ifdef DMAC_DEBUG
    564 static int
    565 dmac_dump_regs(void)
    566 {
    567 	struct dmac_channel_stat *chan = debugchan;
    568 	struct dmac_softc *sc;
    569 
    570 	if ((chan == 0) || (dmacdebug & 0xf0))
    571 		return 0;
    572 	sc = chan->ch_softc;
    573 
    574 	printf("DMAC channel %d registers\n", chan->ch_channel);
    575 	printf("CSR=%02x, CER=%02x, DCR=%02x, OCR=%02x, SCR=%02x, "
    576 		"CCR=%02x, CPR=%02x, GCR=%02x\n",
    577 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CSR),
    578 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CER),
    579 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_DCR),
    580 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_OCR),
    581 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_SCR),
    582 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CCR),
    583 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_CPR),
    584 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_GCR));
    585 	printf("NIVR=%02x, EIVR=%02x, MTCR=%04x, BTCR=%04x, DFCR=%02x, "
    586 		"MFCR=%02x, BFCR=%02x\n",
    587 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_NIVR),
    588 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_EIVR),
    589 		bus_space_read_2(sc->sc_bst, chan->ch_bht, DMAC_REG_MTCR),
    590 		bus_space_read_2(sc->sc_bst, chan->ch_bht, DMAC_REG_BTCR),
    591 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_DFCR),
    592 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_MFCR),
    593 		bus_space_read_1(sc->sc_bst, chan->ch_bht, DMAC_REG_BFCR));
    594 	printf("DAR=%08x, MAR=%08x, BAR=%08x\n",
    595 		bus_space_read_4(sc->sc_bst, chan->ch_bht, DMAC_REG_DAR),
    596 		bus_space_read_4(sc->sc_bst, chan->ch_bht, DMAC_REG_MAR),
    597 		bus_space_read_4(sc->sc_bst, chan->ch_bht, DMAC_REG_BAR));
    598 
    599 	return 0;
    600 }
    601 #endif
    602