pcscp.c revision 1.31 1 /* $NetBSD: pcscp.c,v 1.31 2005/01/02 12:10:34 tsutsui Exp $ */
2
3 /*-
4 * Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center; Izumi Tsutsui.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40 /*
41 * pcscp.c: device dependent code for AMD Am53c974 (PCscsi-PCI)
42 * written by Izumi Tsutsui <tsutsui (at) ceres.dti.ne.jp>
43 *
44 * Technical manual available at
45 * http://www.amd.com/files/connectivitysolutions/networking/archivednetworking/19113.pdf
46 */
47
48 #include <sys/cdefs.h>
49 __KERNEL_RCSID(0, "$NetBSD: pcscp.c,v 1.31 2005/01/02 12:10:34 tsutsui Exp $");
50
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/device.h>
54 #include <sys/buf.h>
55
56 #include <machine/bus.h>
57 #include <machine/intr.h>
58
59 #include <uvm/uvm_extern.h>
60
61 #include <dev/scsipi/scsipi_all.h>
62 #include <dev/scsipi/scsi_all.h>
63 #include <dev/scsipi/scsiconf.h>
64
65 #include <dev/pci/pcireg.h>
66 #include <dev/pci/pcivar.h>
67 #include <dev/pci/pcidevs.h>
68
69 #include <dev/ic/ncr53c9xreg.h>
70 #include <dev/ic/ncr53c9xvar.h>
71
72 #include <dev/pci/pcscpreg.h>
73
74 #define IO_MAP_REG 0x10
75
76 struct pcscp_softc {
77 struct ncr53c9x_softc sc_ncr53c9x; /* glue to MI code */
78
79 bus_space_tag_t sc_st; /* bus space tag */
80 bus_space_handle_t sc_sh; /* bus space handle */
81 void *sc_ih; /* interrupt cookie */
82
83 bus_dma_tag_t sc_dmat; /* DMA tag */
84
85 bus_dmamap_t sc_xfermap; /* DMA map for transfers */
86
87 uint32_t *sc_mdladdr; /* MDL array */
88 bus_dmamap_t sc_mdldmap; /* MDL DMA map */
89
90 int sc_active; /* DMA state */
91 int sc_datain; /* DMA Data Direction */
92 size_t sc_dmasize; /* DMA size */
93 char **sc_dmaaddr; /* DMA address */
94 size_t *sc_dmalen; /* DMA length */
95 };
96
97 #define READ_DMAREG(sc, reg) \
98 bus_space_read_4((sc)->sc_st, (sc)->sc_sh, (reg))
99 #define WRITE_DMAREG(sc, reg, var) \
100 bus_space_write_4((sc)->sc_st, (sc)->sc_sh, (reg), (var))
101
102 #define PCSCP_READ_REG(sc, reg) \
103 bus_space_read_1((sc)->sc_st, (sc)->sc_sh, (reg) << 2)
104 #define PCSCP_WRITE_REG(sc, reg, val) \
105 bus_space_write_1((sc)->sc_st, (sc)->sc_sh, (reg) << 2, (val))
106
107 int pcscp_match(struct device *, struct cfdata *, void *);
108 void pcscp_attach(struct device *, struct device *, void *);
109
110 CFATTACH_DECL(pcscp, sizeof(struct pcscp_softc),
111 pcscp_match, pcscp_attach, NULL, NULL);
112
113 /*
114 * Functions and the switch for the MI code.
115 */
116
117 u_char pcscp_read_reg(struct ncr53c9x_softc *, int);
118 void pcscp_write_reg(struct ncr53c9x_softc *, int, u_char);
119 int pcscp_dma_isintr(struct ncr53c9x_softc *);
120 void pcscp_dma_reset(struct ncr53c9x_softc *);
121 int pcscp_dma_intr(struct ncr53c9x_softc *);
122 int pcscp_dma_setup(struct ncr53c9x_softc *, caddr_t *, size_t *, int,
123 size_t *);
124 void pcscp_dma_go(struct ncr53c9x_softc *);
125 void pcscp_dma_stop(struct ncr53c9x_softc *);
126 int pcscp_dma_isactive(struct ncr53c9x_softc *);
127
128 struct ncr53c9x_glue pcscp_glue = {
129 pcscp_read_reg,
130 pcscp_write_reg,
131 pcscp_dma_isintr,
132 pcscp_dma_reset,
133 pcscp_dma_intr,
134 pcscp_dma_setup,
135 pcscp_dma_go,
136 pcscp_dma_stop,
137 pcscp_dma_isactive,
138 NULL, /* gl_clear_latched_intr */
139 };
140
141 int
142 pcscp_match(struct device *parent, struct cfdata *match, void *aux)
143 {
144 struct pci_attach_args *pa = aux;
145
146 if (PCI_VENDOR(pa->pa_id) != PCI_VENDOR_AMD)
147 return 0;
148
149 switch (PCI_PRODUCT(pa->pa_id)) {
150 case PCI_PRODUCT_AMD_PCSCSI_PCI:
151 return 1;
152 }
153 return 0;
154 }
155
156 /*
157 * Attach this instance, and then all the sub-devices
158 */
159 void
160 pcscp_attach(struct device *parent, struct device *self, void *aux)
161 {
162 struct pci_attach_args *pa = aux;
163 struct pcscp_softc *esc = (void *)self;
164 struct ncr53c9x_softc *sc = &esc->sc_ncr53c9x;
165 bus_space_tag_t iot;
166 bus_space_handle_t ioh;
167 pci_intr_handle_t ih;
168 const char *intrstr;
169 pcireg_t csr;
170 bus_dma_segment_t seg;
171 int error, rseg;
172 char devinfo[256];
173
174 pci_devinfo(pa->pa_id, pa->pa_class, 0, devinfo, sizeof(devinfo));
175 printf(": %s\n", devinfo);
176 printf("%s", sc->sc_dev.dv_xname);
177
178 if (pci_mapreg_map(pa, IO_MAP_REG, PCI_MAPREG_TYPE_IO, 0,
179 &iot, &ioh, NULL, NULL)) {
180 printf(": unable to map registers\n");
181 return;
182 }
183
184 sc->sc_glue = &pcscp_glue;
185
186 esc->sc_st = iot;
187 esc->sc_sh = ioh;
188 esc->sc_dmat = pa->pa_dmat;
189
190 csr = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
191 pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
192 csr | PCI_COMMAND_MASTER_ENABLE | PCI_COMMAND_IO_ENABLE);
193
194 /*
195 * XXX More of this should be in ncr53c9x_attach(), but
196 * XXX should we really poke around the chip that much in
197 * XXX the MI code? Think about this more...
198 */
199
200 /*
201 * Set up static configuration info.
202 */
203
204 /*
205 * XXX should read configuration from EEPROM?
206 *
207 * MI ncr53c9x driver does not support configuration
208 * per each target device, though...
209 */
210 sc->sc_id = 7;
211 sc->sc_cfg1 = sc->sc_id | NCRCFG1_PARENB;
212 sc->sc_cfg2 = NCRCFG2_SCSI2 | NCRCFG2_FE;
213 sc->sc_cfg3 = NCRAMDCFG3_IDM | NCRAMDCFG3_FCLK;
214 sc->sc_cfg4 = NCRAMDCFG4_GE12NS | NCRAMDCFG4_RADE;
215 sc->sc_rev = NCR_VARIANT_AM53C974;
216 sc->sc_features = NCR_F_FASTSCSI;
217 sc->sc_cfg3_fscsi = NCRAMDCFG3_FSCSI;
218 sc->sc_freq = 40; /* MHz */
219
220 /*
221 * XXX minsync and maxxfer _should_ be set up in MI code,
222 * XXX but it appears to have some dependency on what sort
223 * XXX of DMA we're hooked up to, etc.
224 */
225
226 /*
227 * This is the value used to start sync negotiations
228 * Note that the NCR register "SYNCTP" is programmed
229 * in "clocks per byte", and has a minimum value of 4.
230 * The SCSI period used in negotiation is one-fourth
231 * of the time (in nanoseconds) needed to transfer one byte.
232 * Since the chip's clock is given in MHz, we have the following
233 * formula: 4 * period = (1000 / freq) * 4
234 */
235
236 sc->sc_minsync = 1000 / sc->sc_freq;
237
238 /* Really no limit, but since we want to fit into the TCR... */
239 sc->sc_maxxfer = 16 * 1024 * 1024;
240
241 /*
242 * Create the DMA maps for the data transfers.
243 */
244
245 #define MDL_SEG_SIZE 0x1000 /* 4kbyte per segment */
246 #define MDL_SEG_OFFSET 0x0FFF
247 #define MDL_SIZE (MAXPHYS / MDL_SEG_SIZE + 1) /* no hardware limit? */
248
249 if (bus_dmamap_create(esc->sc_dmat, MAXPHYS, MDL_SIZE, MDL_SEG_SIZE,
250 MDL_SEG_SIZE, BUS_DMA_NOWAIT, &esc->sc_xfermap)) {
251 printf(": can't create DMA maps\n");
252 return;
253 }
254
255 /*
256 * Allocate and map memory for the MDL.
257 */
258
259 if ((error = bus_dmamem_alloc(esc->sc_dmat,
260 sizeof(uint32_t) * MDL_SIZE, PAGE_SIZE, 0, &seg, 1, &rseg,
261 BUS_DMA_NOWAIT)) != 0) {
262 printf(": unable to allocate memory for the MDL, error = %d\n",
263 error);
264 return;
265 }
266 if ((error = bus_dmamem_map(esc->sc_dmat, &seg, rseg,
267 sizeof(uint32_t) * MDL_SIZE , (caddr_t *)&esc->sc_mdladdr,
268 BUS_DMA_NOWAIT|BUS_DMA_COHERENT)) != 0) {
269 printf(": unable to map the MDL memory, error = %d\n", error);
270 return;
271 }
272 if ((error = bus_dmamap_create(esc->sc_dmat,
273 sizeof(uint32_t) * MDL_SIZE, 1, sizeof(uint32_t) * MDL_SIZE,
274 0, BUS_DMA_NOWAIT, &esc->sc_mdldmap)) != 0) {
275 printf(": unable to map_create for the MDL, error = %d\n",
276 error);
277 return;
278 }
279 if ((error = bus_dmamap_load(esc->sc_dmat, esc->sc_mdldmap,
280 esc->sc_mdladdr, sizeof(uint32_t) * MDL_SIZE,
281 NULL, BUS_DMA_NOWAIT)) != 0) {
282 printf(": unable to load for the MDL, error = %d\n", error);
283 return;
284 }
285
286 /* map and establish interrupt */
287 if (pci_intr_map(pa, &ih)) {
288 printf(": couldn't map interrupt\n");
289 return;
290 }
291
292 intrstr = pci_intr_string(pa->pa_pc, ih);
293 esc->sc_ih = pci_intr_establish(pa->pa_pc, ih, IPL_BIO,
294 ncr53c9x_intr, esc);
295 if (esc->sc_ih == NULL) {
296 printf(": couldn't establish interrupt");
297 if (intrstr != NULL)
298 printf(" at %s", intrstr);
299 printf("\n");
300 return;
301 }
302 if (intrstr != NULL)
303 printf(": interrupting at %s\n", intrstr);
304
305 /* Do the common parts of attachment. */
306 printf("%s", sc->sc_dev.dv_xname);
307 sc->sc_adapter.adapt_minphys = minphys;
308 sc->sc_adapter.adapt_request = ncr53c9x_scsipi_request;
309 ncr53c9x_attach(sc);
310
311 /* Turn on target selection using the `DMA' method */
312 sc->sc_features |= NCR_F_DMASELECT;
313 }
314
315 /*
316 * Glue functions.
317 */
318
319 u_char
320 pcscp_read_reg(struct ncr53c9x_softc *sc, int reg)
321 {
322 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
323
324 return PCSCP_READ_REG(esc, reg);
325 }
326
327 void
328 pcscp_write_reg(struct ncr53c9x_softc *sc, int reg, u_char v)
329 {
330 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
331
332 PCSCP_WRITE_REG(esc, reg, v);
333 }
334
335 int
336 pcscp_dma_isintr(struct ncr53c9x_softc *sc)
337 {
338 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
339
340 return (PCSCP_READ_REG(esc, NCR_STAT) & NCRSTAT_INT) != 0;
341 }
342
343 void
344 pcscp_dma_reset(struct ncr53c9x_softc *sc)
345 {
346 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
347
348 WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE);
349
350 esc->sc_active = 0;
351 }
352
353 int
354 pcscp_dma_intr(struct ncr53c9x_softc *sc)
355 {
356 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
357 int trans, resid, i;
358 bus_dmamap_t dmap = esc->sc_xfermap;
359 int datain = esc->sc_datain;
360 uint32_t dmastat;
361 char *p = NULL;
362
363 dmastat = READ_DMAREG(esc, DMA_STAT);
364
365 if (dmastat & DMASTAT_ERR) {
366 /* XXX not tested... */
367 WRITE_DMAREG(esc, DMA_CMD,
368 DMACMD_ABORT | (datain ? DMACMD_DIR : 0));
369
370 printf("%s: error: DMA error detected; Aborting.\n",
371 sc->sc_dev.dv_xname);
372 bus_dmamap_unload(esc->sc_dmat, dmap);
373 return -1;
374 }
375
376 if (dmastat & DMASTAT_ABT) {
377 /* XXX What should be done? */
378 printf("%s: dma_intr: DMA aborted.\n", sc->sc_dev.dv_xname);
379 WRITE_DMAREG(esc, DMA_CMD,
380 DMACMD_IDLE | (datain ? DMACMD_DIR : 0));
381 esc->sc_active = 0;
382 return 0;
383 }
384
385 #ifdef DIAGNOSTIC
386 /* This is an "assertion" :) */
387 if (esc->sc_active == 0)
388 panic("pcscp dmaintr: DMA wasn't active");
389 #endif
390
391 /* DMA has stopped */
392
393 esc->sc_active = 0;
394
395 if (esc->sc_dmasize == 0) {
396 /* A "Transfer Pad" operation completed */
397 NCR_DMA(("dmaintr: discarded %d bytes (tcl=%d, tcm=%d)\n",
398 PCSCP_READ_REG(esc, NCR_TCL) |
399 (PCSCP_READ_REG(esc, NCR_TCM) << 8),
400 PCSCP_READ_REG(esc, NCR_TCL),
401 PCSCP_READ_REG(esc, NCR_TCM)));
402 return 0;
403 }
404
405 resid = 0;
406 /*
407 * If a transfer onto the SCSI bus gets interrupted by the device
408 * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
409 * as residual since the ESP counter registers get decremented as
410 * bytes are clocked into the FIFO.
411 */
412 if (!datain &&
413 (resid = (PCSCP_READ_REG(esc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
414 NCR_DMA(("pcscp_dma_intr: empty esp FIFO of %d ", resid));
415 }
416
417 if ((sc->sc_espstat & NCRSTAT_TC) == 0) {
418 /*
419 * `Terminal count' is off, so read the residue
420 * out of the ESP counter registers.
421 */
422 if (datain) {
423 resid = PCSCP_READ_REG(esc, NCR_FFLAG) & NCRFIFO_FF;
424 while (resid > 1)
425 resid =
426 PCSCP_READ_REG(esc, NCR_FFLAG) & NCRFIFO_FF;
427 WRITE_DMAREG(esc, DMA_CMD, DMACMD_BLAST | DMACMD_MDL |
428 (datain ? DMACMD_DIR : 0));
429
430 for (i = 0; i < 0x8000; i++) /* XXX 0x8000 ? */
431 if (READ_DMAREG(esc, DMA_STAT) & DMASTAT_BCMP)
432 break;
433
434 /* See the below comments... */
435 if (resid)
436 p = *esc->sc_dmaaddr;
437 }
438
439 resid += PCSCP_READ_REG(esc, NCR_TCL) |
440 (PCSCP_READ_REG(esc, NCR_TCM) << 8) |
441 (PCSCP_READ_REG(esc, NCR_TCH) << 16);
442 } else {
443 while ((dmastat & DMASTAT_DONE) == 0)
444 dmastat = READ_DMAREG(esc, DMA_STAT);
445 }
446
447 WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | (datain ? DMACMD_DIR : 0));
448
449 /* sync MDL */
450 bus_dmamap_sync(esc->sc_dmat, esc->sc_mdldmap,
451 0, sizeof(uint32_t) * dmap->dm_nsegs, BUS_DMASYNC_POSTWRITE);
452 /* sync transfer buffer */
453 bus_dmamap_sync(esc->sc_dmat, dmap, 0, dmap->dm_mapsize,
454 datain ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
455 bus_dmamap_unload(esc->sc_dmat, dmap);
456
457 trans = esc->sc_dmasize - resid;
458
459 /*
460 * From the technical manual notes:
461 *
462 * `In some odd byte conditions, one residual byte will be left
463 * in the SCSI FIFO, and the FIFO flags will never count to 0.
464 * When this happens, the residual byte should be retrieved
465 * via PIO following completion of the BLAST operation.'
466 */
467
468 if (p) {
469 p += trans;
470 *p = PCSCP_READ_REG(esc, NCR_FIFO);
471 trans++;
472 }
473
474 if (trans < 0) { /* transferred < 0 ? */
475 #if 0
476 /*
477 * This situation can happen in perfectly normal operation
478 * if the ESP is reselected while using DMA to select
479 * another target. As such, don't print the warning.
480 */
481 printf("%s: xfer (%d) > req (%d)\n",
482 sc->sc_dev.dv_xname, trans, esc->sc_dmasize);
483 #endif
484 trans = esc->sc_dmasize;
485 }
486
487 NCR_DMA(("dmaintr: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n",
488 PCSCP_READ_REG(esc, NCR_TCL),
489 PCSCP_READ_REG(esc, NCR_TCM),
490 PCSCP_READ_REG(esc, NCR_TCH),
491 trans, resid));
492
493 *esc->sc_dmalen -= trans;
494 *esc->sc_dmaaddr += trans;
495
496 return 0;
497 }
498
499 int
500 pcscp_dma_setup(struct ncr53c9x_softc *sc, caddr_t *addr, size_t *len,
501 int datain, size_t *dmasize)
502 {
503 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
504 bus_dmamap_t dmap = esc->sc_xfermap;
505 uint32_t *mdl;
506 int error, nseg, seg;
507 bus_addr_t s_offset, s_addr;
508
509 WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | (datain ? DMACMD_DIR : 0));
510
511 esc->sc_dmaaddr = addr;
512 esc->sc_dmalen = len;
513 esc->sc_dmasize = *dmasize;
514 esc->sc_datain = datain;
515
516 #ifdef DIAGNOSTIC
517 if ((*dmasize / MDL_SEG_SIZE) > MDL_SIZE)
518 panic("pcscp: transfer size too large");
519 #endif
520
521 /*
522 * No need to set up DMA in `Transfer Pad' operation.
523 * (case of *dmasize == 0)
524 */
525 if (*dmasize == 0)
526 return 0;
527
528 error = bus_dmamap_load(esc->sc_dmat, dmap, *esc->sc_dmaaddr,
529 *esc->sc_dmalen, NULL,
530 ((sc->sc_nexus->xs->xs_control & XS_CTL_NOSLEEP) ?
531 BUS_DMA_NOWAIT : BUS_DMA_WAITOK) | BUS_DMA_STREAMING |
532 ((sc->sc_nexus->xs->xs_control & XS_CTL_DATA_IN) ?
533 BUS_DMA_READ : BUS_DMA_WRITE));
534 if (error) {
535 printf("%s: unable to load dmamap, error = %d\n",
536 sc->sc_dev.dv_xname, error);
537 return error;
538 }
539
540 /* set transfer length */
541 WRITE_DMAREG(esc, DMA_STC, *dmasize);
542
543 /* set up MDL */
544 mdl = esc->sc_mdladdr;
545 nseg = dmap->dm_nsegs;
546
547 /* the first segment is possibly not aligned with 4k MDL boundary */
548 s_addr = dmap->dm_segs[0].ds_addr;
549 s_offset = s_addr & MDL_SEG_OFFSET;
550 s_addr -= s_offset;
551
552 /* set the first MDL and offset */
553 WRITE_DMAREG(esc, DMA_SPA, s_offset);
554 *mdl++ = htole32(s_addr);
555
556 /* the rest dmamap segments are aligned with 4k boundary */
557 for (seg = 1; seg < nseg; seg++)
558 *mdl++ = htole32(dmap->dm_segs[seg].ds_addr);
559
560 return 0;
561 }
562
563 void
564 pcscp_dma_go(struct ncr53c9x_softc *sc)
565 {
566 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
567 bus_dmamap_t dmap = esc->sc_xfermap, mdldmap = esc->sc_mdldmap;
568 int datain = esc->sc_datain;
569
570 /* No DMA transfer in Transfer Pad operation */
571 if (esc->sc_dmasize == 0)
572 return;
573
574 /* sync transfer buffer */
575 bus_dmamap_sync(esc->sc_dmat, dmap, 0, dmap->dm_mapsize,
576 datain ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
577
578 /* sync MDL */
579 bus_dmamap_sync(esc->sc_dmat, mdldmap,
580 0, sizeof(uint32_t) * dmap->dm_nsegs, BUS_DMASYNC_PREWRITE);
581
582 /* set Starting MDL Address */
583 WRITE_DMAREG(esc, DMA_SMDLA, mdldmap->dm_segs[0].ds_addr);
584
585 /* set DMA command register bits */
586 /* XXX DMA Transfer Interrupt Enable bit is broken? */
587 WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | DMACMD_MDL |
588 /* DMACMD_INTE | */
589 (datain ? DMACMD_DIR : 0));
590
591 /* issue DMA start command */
592 WRITE_DMAREG(esc, DMA_CMD, DMACMD_START | DMACMD_MDL |
593 /* DMACMD_INTE | */
594 (datain ? DMACMD_DIR : 0));
595
596 esc->sc_active = 1;
597 }
598
599 void
600 pcscp_dma_stop(struct ncr53c9x_softc *sc)
601 {
602 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
603
604 /* DMA stop */
605 /* XXX What should we do here ? */
606 WRITE_DMAREG(esc, DMA_CMD,
607 DMACMD_ABORT | (esc->sc_datain ? DMACMD_DIR : 0));
608
609 esc->sc_active = 0;
610 }
611
612 int
613 pcscp_dma_isactive(struct ncr53c9x_softc *sc)
614 {
615 struct pcscp_softc *esc = (struct pcscp_softc *)sc;
616
617 /* XXX should check esc->sc_active? */
618 if ((READ_DMAREG(esc, DMA_CMD) & DMACMD_CMD) != DMACMD_IDLE)
619 return 1;
620 return 0;
621 }
622