1 /*	$NetBSD: si.c,v 1.23 2008/12/17 19:13:02 cegger Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996,2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Adam Glass, David Jones, Gordon W. Ross, Jason R. Thorpe and
9  * Paul Kranenburg.
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  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * This file contains VME bus-dependent of the `si' SCSI adapter.
35  * This hardware is frequently found on Sun 3 and Sun 4 machines.
36  *
37  * The SCSI machinery on this adapter is implemented by an NCR5380,
38  * which is taken care of by the chipset driver in /sys/dev/ic/ncr5380sbc.c
39  *
40  * The logic has a bit to enable or disable the DMA engine,
41  * but that bit also gates the interrupt line from the NCR5380!
42  * Therefore, in order to get any interrupt from the 5380, (i.e.
43  * for reselect) one must clear the DMA engine transfer count and
44  * then enable DMA.  This has the further complication that you
45  * CAN NOT touch the NCR5380 while the DMA enable bit is set, so
46  * we have to turn DMA back off before we even look at the 5380.
47  *
48  * What wonderfully whacky hardware this is!
49  *
50  */
51 
52 /*
53  * This driver originated as an MD implementation for the sun3 and sun4
54  * ports. The notes pertaining to that history are included below.
55  *
56  * David Jones wrote the initial version of this module for NetBSD/sun3,
57  * which included support for the VME adapter only. (no reselection).
58  *
59  * Gordon Ross added support for the Sun 3 OBIO adapter, and re-worked
60  * both the VME and OBIO code to support disconnect/reselect.
61  * (Required figuring out the hardware "features" noted above.)
62  *
63  * The autoconfiguration boilerplate came from Adam Glass.
64  *
65  * Jason R. Thorpe ported the autoconfiguration and VME portions to
66  * NetBSD/sparc, and added initial support for the 4/100 "SCSI Weird",
67  * a wacky OBIO variant of the VME SCSI-3.  Many thanks to Chuck Cranor
68  * for lots of helpful tips and suggestions.  Thanks also to Paul Kranenburg
69  * and Chris Torek for bits of insight needed along the way.  Thanks to
70  * David Gilbert and Andrew Gillham who risked filesystem life-and-limb
71  * for the sake of testing.  Andrew Gillham helped work out the bugs
72  * the 4/100 DMA code.
73  */
74 
75 #include <sys/cdefs.h>
76 __KERNEL_RCSID(0, "$NetBSD: si.c,v 1.23 2008/12/17 19:13:02 cegger Exp $");
77 
78 #include "opt_ddb.h"
79 
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/kernel.h>
83 #include <sys/malloc.h>
84 #include <sys/errno.h>
85 #include <sys/device.h>
86 #include <sys/buf.h>
87 
88 #include <sys/bus.h>
89 #include <sys/intr.h>
90 
91 #include <dev/vme/vmereg.h>
92 #include <dev/vme/vmevar.h>
93 
94 #include <dev/scsipi/scsi_all.h>
95 #include <dev/scsipi/scsipi_all.h>
96 #include <dev/scsipi/scsipi_debug.h>
97 #include <dev/scsipi/scsiconf.h>
98 
99 #ifndef Debugger
100 #define	Debugger()
101 #endif
102 
103 #ifndef DEBUG
104 #define DEBUG XXX
105 #endif
106 
107 #include <dev/ic/ncr5380reg.h>
108 #include <dev/ic/ncr5380var.h>
109 
110 #include <dev/vme/sireg.h>
111 
112 /*
113  * Transfers smaller than this are done using PIO
114  * (on assumption they're not worth DMA overhead)
115  */
116 #define	MIN_DMA_LEN 128
117 
118 #ifdef	DEBUG
119 int si_debug = 0;
120 #endif
121 
122 /*
123  * This structure is used to keep track of mapped DMA requests.
124  */
125 struct si_dma_handle {
126 	int 		dh_flags;
127 #define	SIDH_BUSY	0x01		/* This DH is in use */
128 #define	SIDH_OUT	0x02		/* DMA does data out (write) */
129 	int 		dh_maplen;	/* Original data length */
130 	bus_dmamap_t	dh_dmamap;
131 #define dh_dvma	dh_dmamap->dm_segs[0].ds_addr /* VA of buffer in DVMA space */
132 };
133 
134 /*
135  * The first structure member has to be the ncr5380_softc
136  * so we can just cast to go back and fourth between them.
137  */
138 struct si_softc {
139 	struct ncr5380_softc	ncr_sc;
140 	bus_space_tag_t		sc_bustag;	/* bus tags */
141 	bus_dma_tag_t		sc_dmatag;
142 	vme_chipset_tag_t	sc_vctag;
143 
144 	int		sc_adapter_iv_am; /* int. vec + address modifier */
145 	struct si_dma_handle *sc_dma;
146 	int		sc_xlen;	/* length of current DMA segment. */
147 	int		sc_options;	/* options for this instance. */
148 };
149 
150 /*
151  * Options.  By default, DMA is enabled and DMA completion interrupts
152  * and reselect are disabled.  You may enable additional features
153  * the `flags' directive in your kernel's configuration file.
154  *
155  * Alternatively, you can patch your kernel with DDB or some other
156  * mechanism.  The sc_options member of the softc is OR'd with
157  * the value in si_options.
158  *
159  * Note, there's a separate sw_options to make life easier.
160  */
161 #define	SI_ENABLE_DMA	0x01	/* Use DMA (maybe polled) */
162 #define	SI_DMA_INTR	0x02	/* DMA completion interrupts */
163 #define	SI_DO_RESELECT	0x04	/* Allow disconnect/reselect */
164 #define	SI_OPTIONS_MASK	(SI_ENABLE_DMA|SI_DMA_INTR|SI_DO_RESELECT)
165 #define SI_OPTIONS_BITS	"\10\3RESELECT\2DMA_INTR\1DMA"
166 int si_options = SI_ENABLE_DMA|SI_DMA_INTR|SI_DO_RESELECT;
167 
168 static int	si_match(device_t, cfdata_t, void *);
169 static void	si_attach(device_t, device_t, void *);
170 static int	si_intr(void *);
171 static void	si_reset_adapter(struct ncr5380_softc *);
172 
173 void	si_dma_alloc(struct ncr5380_softc *);
174 void	si_dma_free(struct ncr5380_softc *);
175 void	si_dma_poll(struct ncr5380_softc *);
176 
177 void	si_dma_setup(struct ncr5380_softc *);
178 void	si_dma_start(struct ncr5380_softc *);
179 void	si_dma_eop(struct ncr5380_softc *);
180 void	si_dma_stop(struct ncr5380_softc *);
181 
182 void	si_intr_on (struct ncr5380_softc *);
183 void	si_intr_off(struct ncr5380_softc *);
184 
185 /*
186  * Shorthand bus space access
187  * XXX - must look into endian issues here.
188  */
189 #define SIREG_READ(sc, index) \
190 	bus_space_read_2((sc)->sc_regt, (sc)->sc_regh, index)
191 #define SIREG_WRITE(sc, index, v) \
192 	bus_space_write_2((sc)->sc_regt, (sc)->sc_regh, index, v)
193 
194 
195 /* Auto-configuration glue. */
196 CFATTACH_DECL_NEW(si, sizeof(struct si_softc),
197     si_match, si_attach, NULL, NULL);
198 
199 static int
si_match(device_t parent,cfdata_t cf,void * aux)200 si_match(device_t parent, cfdata_t cf, void *aux)
201 {
202 	struct vme_attach_args	*va = aux;
203 	vme_chipset_tag_t	ct = va->va_vct;
204         vme_am_t		mod;
205         vme_addr_t		vme_addr;
206 
207 	/* Make sure there is something there... */
208 	mod = VME_AM_A24 | VME_AM_MBO | VME_AM_SUPER | VME_AM_DATA;
209 	vme_addr = va->r[0].offset;
210 
211 	if (vme_probe(ct, vme_addr, 1, mod, VME_D8, NULL, 0) != 0)
212 		return 0;
213 
214 	/*
215 	 * If this is a VME SCSI board, we have to determine whether
216 	 * it is an "sc" (Sun2) or "si" (Sun3) SCSI board.  This can
217 	 * be determined using the fact that the "sc" board occupies
218 	 * 4K bytes in VME space but the "si" board occupies 2K bytes.
219 	 */
220 	return vme_probe(ct, vme_addr + 0x801, 1, mod, VME_D8, NULL, 0) != 0;
221 }
222 
223 static void
si_attach(device_t parent,device_t self,void * aux)224 si_attach(device_t parent, device_t self, void *aux)
225 {
226 	struct si_softc		*sc = device_private(self);
227 	struct ncr5380_softc *ncr_sc = &sc->ncr_sc;
228 	struct vme_attach_args	*va = aux;
229 	vme_chipset_tag_t	ct = va->va_vct;
230 	bus_space_tag_t		bt;
231 	bus_space_handle_t	bh;
232 	vme_mapresc_t resc;
233 	vme_intr_handle_t	ih;
234 	vme_am_t		mod;
235 	char bits[64];
236 	int i;
237 
238 	ncr_sc->sc_dev = self;
239 	sc->sc_dmatag = va->va_bdt;
240 	sc->sc_vctag = ct;
241 
242 	mod = VME_AM_A24 | VME_AM_MBO | VME_AM_SUPER | VME_AM_DATA;
243 
244 	if (vme_space_map(ct, va->r[0].offset, SIREG_BANK_SZ,
245 			  mod, VME_D8, 0, &bt, &bh, &resc) != 0)
246 		panic("%s: vme_space_map", device_xname(self));
247 
248 	ncr_sc->sc_regt = bt;
249 	ncr_sc->sc_regh = bh;
250 
251 	sc->sc_options = si_options;
252 
253 	ncr_sc->sc_dma_setup = si_dma_setup;
254 	ncr_sc->sc_dma_start = si_dma_start;
255 	ncr_sc->sc_dma_eop   = si_dma_stop;
256 	ncr_sc->sc_dma_stop  = si_dma_stop;
257 
258 	vme_intr_map(ct, va->ilevel, va->ivector, &ih);
259 	vme_intr_establish(ct, ih, IPL_BIO, si_intr, sc);
260 
261 	aprint_normal("\n");
262 
263 	sc->sc_adapter_iv_am = (mod << 8) | (va->ivector & 0xFF);
264 
265 	/*
266 	 * Pull in the options flags.  Allow the user to completely
267 	 * override the default values.
268 	 */
269 	if ((device_cfdata(self)->cf_flags & SI_OPTIONS_MASK) != 0)
270 		sc->sc_options =
271 		    device_cfdata(self)->cf_flags & SI_OPTIONS_MASK;
272 
273 	/*
274 	 * Initialize fields used by the MI code
275 	 */
276 
277 	/* NCR5380 register bank offsets */
278 	ncr_sc->sci_r0 = 0;
279 	ncr_sc->sci_r1 = 1;
280 	ncr_sc->sci_r2 = 2;
281 	ncr_sc->sci_r3 = 3;
282 	ncr_sc->sci_r4 = 4;
283 	ncr_sc->sci_r5 = 5;
284 	ncr_sc->sci_r6 = 6;
285 	ncr_sc->sci_r7 = 7;
286 
287 	ncr_sc->sc_rev = NCR_VARIANT_NCR5380;
288 
289 	/*
290 	 * MD function pointers used by the MI code.
291 	 */
292 	ncr_sc->sc_pio_out = ncr5380_pio_out;
293 	ncr_sc->sc_pio_in =  ncr5380_pio_in;
294 	ncr_sc->sc_dma_alloc = si_dma_alloc;
295 	ncr_sc->sc_dma_free  = si_dma_free;
296 	ncr_sc->sc_dma_poll  = si_dma_poll;
297 
298 	ncr_sc->sc_flags = 0;
299 	if ((sc->sc_options & SI_DO_RESELECT) == 0)
300 		ncr_sc->sc_no_disconnect = 0xFF;
301 	if ((sc->sc_options & SI_DMA_INTR) == 0)
302 		ncr_sc->sc_flags |= NCR5380_FORCE_POLLING;
303 	ncr_sc->sc_min_dma_len = MIN_DMA_LEN;
304 
305 	/*
306 	 * Allocate DMA handles.
307 	 */
308 	i = SCI_OPENINGS * sizeof(struct si_dma_handle);
309 	sc->sc_dma = malloc(i, M_DEVBUF, M_NOWAIT);
310 	if (sc->sc_dma == NULL)
311 		panic("si: DMA handle malloc failed");
312 
313 	for (i = 0; i < SCI_OPENINGS; i++) {
314 		sc->sc_dma[i].dh_flags = 0;
315 
316 		/* Allocate a DMA handle */
317 		if (vme_dmamap_create(
318 				sc->sc_vctag,	/* VME chip tag */
319 				MAXPHYS,	/* size */
320 				VME_AM_A24,	/* address modifier */
321 				VME_D16,	/* data size */
322 				0,		/* swap */
323 				1,		/* nsegments */
324 				MAXPHYS,	/* maxsegsz */
325 				0,		/* boundary */
326 				BUS_DMA_NOWAIT,
327 				&sc->sc_dma[i].dh_dmamap) != 0) {
328 
329 			aprint_error_dev(self, "DMA buffer map create error\n");
330 			return;
331 		}
332 	}
333 
334 	if (sc->sc_options) {
335 		snprintb(bits, sizeof(bits), SI_OPTIONS_BITS, sc->sc_options);
336 		aprint_normal_dev(self, "options=%s\n", bits);
337 	}
338 
339 	ncr_sc->sc_channel.chan_id = 7;
340 	ncr_sc->sc_adapter.adapt_minphys = minphys;
341 
342 	/*
343 	 *  Initialize si board itself.
344 	 */
345 	si_reset_adapter(ncr_sc);
346 	ncr5380_attach(ncr_sc);
347 
348 	if (sc->sc_options & SI_DO_RESELECT) {
349 		/*
350 		 * Need to enable interrupts (and DMA!)
351 		 * on this H/W for reselect to work.
352 		 */
353 		ncr_sc->sc_intr_on   = si_intr_on;
354 		ncr_sc->sc_intr_off  = si_intr_off;
355 	}
356 }
357 
358 #define CSR_WANT (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
359 	SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR )
360 
361 static int
si_intr(void * arg)362 si_intr(void *arg)
363 {
364 	struct si_softc *sc = arg;
365 	struct ncr5380_softc *ncr_sc = &sc->ncr_sc;
366 	int dma_error, claimed;
367 	uint16_t csr;
368 
369 	claimed = 0;
370 	dma_error = 0;
371 
372 	/* SBC interrupt? DMA interrupt? */
373 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
374 
375 	NCR_TRACE("si_intr: csr=0x%x\n", csr);
376 
377 	if (csr & SI_CSR_DMA_CONFLICT) {
378 		dma_error |= SI_CSR_DMA_CONFLICT;
379 		printf("%s: DMA conflict\n", __func__);
380 	}
381 	if (csr & SI_CSR_DMA_BUS_ERR) {
382 		dma_error |= SI_CSR_DMA_BUS_ERR;
383 		printf("%s: DMA bus error\n", __func__);
384 	}
385 	if (dma_error) {
386 		if (sc->ncr_sc.sc_state & NCR_DOINGDMA)
387 			sc->ncr_sc.sc_state |= NCR_ABORTING;
388 		/* Make sure we will call the main isr. */
389 		csr |= SI_CSR_DMA_IP;
390 	}
391 
392 	if (csr & (SI_CSR_SBC_IP | SI_CSR_DMA_IP)) {
393 		claimed = ncr5380_intr(&sc->ncr_sc);
394 #ifdef DEBUG
395 		if (!claimed) {
396 			printf("%s: spurious from SBC\n", __func__);
397 			if (si_debug & 4) {
398 				Debugger();	/* XXX */
399 			}
400 		}
401 #endif
402 	}
403 
404 	return claimed;
405 }
406 
407 
408 static void
si_reset_adapter(struct ncr5380_softc * ncr_sc)409 si_reset_adapter(struct ncr5380_softc *ncr_sc)
410 {
411 	struct si_softc *sc = (struct si_softc *)ncr_sc;
412 
413 #ifdef	DEBUG
414 	if (si_debug) {
415 		printf("%s\n", __func__);
416 	}
417 #endif
418 
419 	/*
420 	 * The SCSI3 controller has an 8K FIFO to buffer data between the
421 	 * 5380 and the DMA.  Make sure it starts out empty.
422 	 *
423 	 * The reset bits in the CSR are active low.
424 	 */
425 	SIREG_WRITE(ncr_sc, SIREG_CSR, 0);
426 	delay(10);
427 	SIREG_WRITE(ncr_sc, SIREG_CSR,
428 	    SI_CSR_FIFO_RES | SI_CSR_SCSI_RES | SI_CSR_INTR_EN);
429 	delay(10);
430 
431 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, 0);
432 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, 0);
433 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, 0);
434 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
435 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
436 	SIREG_WRITE(ncr_sc, SIREG_IV_AM, sc->sc_adapter_iv_am);
437 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, 0);
438 
439 	SCI_CLR_INTR(ncr_sc);
440 }
441 
442 /*****************************************************************
443  * Common functions for DMA
444  ****************************************************************/
445 
446 /*
447  * Allocate a DMA handle and put it in sc->sc_dma.  Prepare
448  * for DMA transfer.
449  */
450 void
si_dma_alloc(struct ncr5380_softc * ncr_sc)451 si_dma_alloc(struct ncr5380_softc *ncr_sc)
452 {
453 	struct si_softc *sc = (struct si_softc *)ncr_sc;
454 	struct sci_req *sr = ncr_sc->sc_current;
455 	struct scsipi_xfer *xs = sr->sr_xs;
456 	struct si_dma_handle *dh;
457 	int i, xlen;
458 	u_long addr;
459 
460 #ifdef DIAGNOSTIC
461 	if (sr->sr_dma_hand != NULL)
462 		panic("%s: already have DMA handle", __func__);
463 #endif
464 
465 #if 1	/* XXX - Temporary */
466 	/* XXX - In case we think DMA is completely broken... */
467 	if ((sc->sc_options & SI_ENABLE_DMA) == 0)
468 		return;
469 #endif
470 
471 	addr = (u_long)ncr_sc->sc_dataptr;
472 	xlen = ncr_sc->sc_datalen;
473 
474 	/* If the DMA start addr is misaligned then do PIO */
475 	if ((addr & 1) || (xlen & 1)) {
476 		printf("%s: misaligned.\n", __func__);
477 		return;
478 	}
479 
480 	/* Make sure our caller checked sc_min_dma_len. */
481 	if (xlen < MIN_DMA_LEN)
482 		panic("%s: xlen=0x%x", __func__, xlen);
483 
484 	/* Find free DMA handle.  Guaranteed to find one since we have
485 	   as many DMA handles as the driver has processes. */
486 	for (i = 0; i < SCI_OPENINGS; i++) {
487 		if ((sc->sc_dma[i].dh_flags & SIDH_BUSY) == 0)
488 			goto found;
489 	}
490 	panic("si: no free DMA handles.");
491 
492 found:
493 	dh = &sc->sc_dma[i];
494 	dh->dh_flags = SIDH_BUSY;
495 	dh->dh_maplen  = xlen;
496 
497 	/* Copy the "write" flag for convenience. */
498 	if ((xs->xs_control & XS_CTL_DATA_OUT) != 0)
499 		dh->dh_flags |= SIDH_OUT;
500 
501 	/*
502 	 * Double-map the buffer into DVMA space.  If we can't re-map
503 	 * the buffer, we print a warning and fall back to PIO mode.
504 	 *
505 	 * NOTE: it is not safe to sleep here!
506 	 */
507 	if (bus_dmamap_load(sc->sc_dmatag, dh->dh_dmamap,
508 			    (void *)addr, xlen, NULL, BUS_DMA_NOWAIT) != 0) {
509 		/* Can't remap segment */
510 		printf("%s: can't remap 0x%lx/0x%x, doing PIO\n",
511 		    __func__, addr, dh->dh_maplen);
512 		dh->dh_flags = 0;
513 		return;
514 	}
515 	bus_dmamap_sync(sc->sc_dmatag, dh->dh_dmamap, addr, xlen,
516 			(dh->dh_flags & SIDH_OUT)
517 				? BUS_DMASYNC_PREWRITE
518 				: BUS_DMASYNC_PREREAD);
519 
520 	/* success */
521 	sr->sr_dma_hand = dh;
522 }
523 
524 
525 void
si_dma_free(struct ncr5380_softc * ncr_sc)526 si_dma_free(struct ncr5380_softc *ncr_sc)
527 {
528 	struct si_softc *sc = (struct si_softc *)ncr_sc;
529 	struct sci_req *sr = ncr_sc->sc_current;
530 	struct si_dma_handle *dh = sr->sr_dma_hand;
531 
532 #ifdef DIAGNOSTIC
533 	if (dh == NULL)
534 		panic("%s: no DMA handle", __func__);
535 #endif
536 
537 	if (ncr_sc->sc_state & NCR_DOINGDMA)
538 		panic("%s: free while in progress", __func__);
539 
540 	if (dh->dh_flags & SIDH_BUSY) {
541 		/* Give back the DVMA space. */
542 		bus_dmamap_sync(sc->sc_dmatag, dh->dh_dmamap,
543 				dh->dh_dvma, dh->dh_maplen,
544 				(dh->dh_flags & SIDH_OUT)
545 					? BUS_DMASYNC_POSTWRITE
546 					: BUS_DMASYNC_POSTREAD);
547 		bus_dmamap_unload(sc->sc_dmatag, dh->dh_dmamap);
548 		dh->dh_flags = 0;
549 	}
550 	sr->sr_dma_hand = NULL;
551 }
552 
553 
554 /*
555  * Poll (spin-wait) for DMA completion.
556  * Called right after xx_dma_start(), and
557  * xx_dma_stop() will be called next.
558  * Same for either VME or OBIO.
559  */
560 void
si_dma_poll(struct ncr5380_softc * ncr_sc)561 si_dma_poll(struct ncr5380_softc *ncr_sc)
562 {
563 	struct sci_req *sr = ncr_sc->sc_current;
564 	int tmo, csr_mask, csr;
565 
566 	/* Make sure DMA started successfully. */
567 	if (ncr_sc->sc_state & NCR_ABORTING)
568 		return;
569 
570 	csr_mask = SI_CSR_SBC_IP | SI_CSR_DMA_IP |
571 		SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR;
572 
573 	tmo = 50000;	/* X100 = 5 sec. */
574 	for (;;) {
575 		csr = SIREG_READ(ncr_sc, SIREG_CSR);
576 		if (csr & csr_mask)
577 			break;
578 		if (--tmo <= 0) {
579 			printf("%s: DMA timeout (while polling)\n",
580 			    device_xname(ncr_sc->sc_dev));
581 			/* Indicate timeout as MI code would. */
582 			sr->sr_flags |= SR_OVERDUE;
583 			break;
584 		}
585 		delay(100);
586 	}
587 
588 #ifdef	DEBUG
589 	if (si_debug) {
590 		printf("%s: done, csr=0x%x\n", __func__, csr);
591 	}
592 #endif
593 }
594 
595 
596 /*****************************************************************
597  * VME functions for DMA
598  ****************************************************************/
599 
600 
601 /*
602  * This is called when the bus is going idle,
603  * so we want to enable the SBC interrupts.
604  * That is controlled by the DMA enable!
605  * Who would have guessed!
606  * What a NASTY trick!
607  */
608 void
si_intr_on(struct ncr5380_softc * ncr_sc)609 si_intr_on(struct ncr5380_softc *ncr_sc)
610 {
611 	uint16_t csr;
612 
613 	/* Clear DMA start address and counters */
614 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, 0);
615 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, 0);
616 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
617 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
618 
619 	/* Enter receive mode (for safety) and enable DMA engine */
620 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
621 	csr &= ~SI_CSR_SEND;
622 	csr |= SI_CSR_DMA_EN;
623 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
624 }
625 
626 /*
627  * This is called when the bus is idle and we are
628  * about to start playing with the SBC chip.
629  */
630 void
si_intr_off(struct ncr5380_softc * ncr_sc)631 si_intr_off(struct ncr5380_softc *ncr_sc)
632 {
633 	uint16_t csr;
634 
635 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
636 	csr &= ~SI_CSR_DMA_EN;
637 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
638 }
639 
640 /*
641  * This function is called during the COMMAND or MSG_IN phase
642  * that precedes a DATA_IN or DATA_OUT phase, in case we need
643  * to setup the DMA engine before the bus enters a DATA phase.
644  *
645  * XXX: The VME adapter appears to suppress SBC interrupts
646  * when the FIFO is not empty or the FIFO count is non-zero!
647  *
648  * On the VME version we just clear the DMA count and address
649  * here (to make sure it stays idle) and do the real setup
650  * later, in dma_start.
651  */
652 void
si_dma_setup(struct ncr5380_softc * ncr_sc)653 si_dma_setup(struct ncr5380_softc *ncr_sc)
654 {
655 	struct si_softc *sc = (struct si_softc *)ncr_sc;
656 	struct sci_req *sr = ncr_sc->sc_current;
657 	struct si_dma_handle *dh = sr->sr_dma_hand;
658 	uint16_t csr;
659 	u_long dva;
660 	int xlen;
661 
662 	/*
663 	 * Set up the DMA controller.
664 	 * Note that (dh->dh_len < sc_datalen)
665 	 */
666 
667 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
668 
669 	/* Disable DMA while we're setting up the transfer */
670 	csr &= ~SI_CSR_DMA_EN;
671 
672 	/* Reset the FIFO */
673 	csr &= ~SI_CSR_FIFO_RES;		/* active low */
674 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
675 	csr |= SI_CSR_FIFO_RES;
676 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
677 
678 	/*
679 	 * Get the DVMA mapping for this segment.
680 	 */
681 	dva = (u_long)(dh->dh_dvma);
682 	if (dva & 1)
683 		panic("%s: bad dmaaddr=0x%lx", __func__, dva);
684 	xlen = ncr_sc->sc_datalen;
685 	xlen &= ~1;
686 	sc->sc_xlen = xlen;	/* XXX: or less... */
687 
688 #ifdef	DEBUG
689 	if (si_debug & 2) {
690 		printf("%s: dh=%p, dmaaddr=0x%lx, xlen=%d\n",
691 		    __func__, dh, dva, xlen);
692 	}
693 #endif
694 	/* Set direction (send/recv) */
695 	if (dh->dh_flags & SIDH_OUT) {
696 		csr |= SI_CSR_SEND;
697 	} else {
698 		csr &= ~SI_CSR_SEND;
699 	}
700 
701 	/* Set byte-packing control */
702 	if (dva & 2) {
703 		csr |= SI_CSR_BPCON;
704 	} else {
705 		csr &= ~SI_CSR_BPCON;
706 	}
707 
708 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
709 
710 	/* Load start address */
711 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, (uint16_t)(dva >> 16));
712 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, (uint16_t)(dva & 0xFFFF));
713 
714 	/* Clear DMA counters; these will be set in si_dma_start() */
715 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
716 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
717 
718 	/* Clear FIFO counter. (also hits dma_count) */
719 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, 0);
720 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, 0);
721 }
722 
723 
724 void
si_dma_start(struct ncr5380_softc * ncr_sc)725 si_dma_start(struct ncr5380_softc *ncr_sc)
726 {
727 	struct si_softc *sc = (struct si_softc *)ncr_sc;
728 	struct sci_req *sr = ncr_sc->sc_current;
729 	struct si_dma_handle *dh = sr->sr_dma_hand;
730 	int xlen;
731 	u_int mode;
732 	uint16_t csr;
733 
734 	xlen = sc->sc_xlen;
735 
736 	/* Load transfer length */
737 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, (uint16_t)(xlen >> 16));
738 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, (uint16_t)(xlen & 0xFFFF));
739 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, (uint16_t)(xlen >> 16));
740 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, (uint16_t)(xlen & 0xFFFF));
741 
742 	/*
743 	 * Acknowledge the phase change.  (After DMA setup!)
744 	 * Put the SBIC into DMA mode, and start the transfer.
745 	 */
746 	if (dh->dh_flags & SIDH_OUT) {
747 		NCR5380_WRITE(ncr_sc, sci_tcmd, PHASE_DATA_OUT);
748 		SCI_CLR_INTR(ncr_sc);
749 		NCR5380_WRITE(ncr_sc, sci_icmd, SCI_ICMD_DATA);
750 
751 		mode = NCR5380_READ(ncr_sc, sci_mode);
752 		mode |= (SCI_MODE_DMA | SCI_MODE_DMA_IE);
753 		NCR5380_WRITE(ncr_sc, sci_mode, mode);
754 
755 		NCR5380_WRITE(ncr_sc, sci_dma_send, 0); /* start it */
756 	} else {
757 		NCR5380_WRITE(ncr_sc, sci_tcmd, PHASE_DATA_IN);
758 		SCI_CLR_INTR(ncr_sc);
759 		NCR5380_WRITE(ncr_sc, sci_icmd, 0);
760 
761 		mode = NCR5380_READ(ncr_sc, sci_mode);
762 		mode |= (SCI_MODE_DMA | SCI_MODE_DMA_IE);
763 		NCR5380_WRITE(ncr_sc, sci_mode, mode);
764 
765 		NCR5380_WRITE(ncr_sc, sci_irecv, 0); /* start it */
766 	}
767 
768 	ncr_sc->sc_state |= NCR_DOINGDMA;
769 
770 	/* Enable DMA engine */
771 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
772 	csr |= SI_CSR_DMA_EN;
773 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
774 
775 #ifdef	DEBUG
776 	if (si_debug & 2) {
777 		printf("%s: started, flags=0x%x\n",
778 		    __func__, ncr_sc->sc_state);
779 	}
780 #endif
781 }
782 
783 
784 void
si_dma_eop(struct ncr5380_softc * ncr_sc)785 si_dma_eop(struct ncr5380_softc *ncr_sc)
786 {
787 
788 	/* Not needed - DMA was stopped prior to examining sci_csr */
789 }
790 
791 
792 void
si_dma_stop(struct ncr5380_softc * ncr_sc)793 si_dma_stop(struct ncr5380_softc *ncr_sc)
794 {
795 	struct si_softc *sc = (struct si_softc *)ncr_sc;
796 	struct sci_req *sr = ncr_sc->sc_current;
797 	struct si_dma_handle *dh = sr->sr_dma_hand;
798 	int resid, ntrans;
799 	uint16_t csr;
800 	u_int mode;
801 
802 	if ((ncr_sc->sc_state & NCR_DOINGDMA) == 0) {
803 #ifdef	DEBUG
804 		printf("%s: DMA not running\n", __func__);
805 #endif
806 		return;
807 	}
808 
809 	ncr_sc->sc_state &= ~NCR_DOINGDMA;
810 
811 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
812 
813 	/* First, halt the DMA engine. */
814 	csr &= ~SI_CSR_DMA_EN;
815 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
816 
817 	if (csr & (SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR)) {
818 		printf("si: DMA error, csr=0x%x, reset\n", csr);
819 		sr->sr_xs->error = XS_DRIVER_STUFFUP;
820 		ncr_sc->sc_state |= NCR_ABORTING;
821 		si_reset_adapter(ncr_sc);
822 	}
823 
824 	/* Note that timeout may have set the error flag. */
825 	if (ncr_sc->sc_state & NCR_ABORTING)
826 		goto out;
827 
828 	/*
829 	 * Now try to figure out how much actually transferred
830 	 *
831 	 * The fifo_count does not reflect how many bytes were
832 	 * actually transferred for VME.
833 	 *
834 	 * SCSI-3 VME interface is a little funny on writes:
835 	 * if we have a disconnect, the DMA has overshot by
836 	 * one byte and the resid needs to be incremented.
837 	 * Only happens for partial transfers.
838 	 * (Thanks to Matt Jacob)
839 	 */
840 
841 	resid = SIREG_READ(ncr_sc, SIREG_FIFO_CNTH) << 16;
842 	resid |= SIREG_READ(ncr_sc, SIREG_FIFO_CNT) & 0xFFFF;
843 	if (dh->dh_flags & SIDH_OUT)
844 		if ((resid > 0) && (resid < sc->sc_xlen))
845 			resid++;
846 	ntrans = sc->sc_xlen - resid;
847 
848 #ifdef	DEBUG
849 	if (si_debug & 2) {
850 		printf("%s: resid=0x%x ntrans=0x%x\n",
851 		    __func__, resid, ntrans);
852 	}
853 #endif
854 
855 	if (ntrans > ncr_sc->sc_datalen)
856 		panic("%s: excess transfer", __func__);
857 
858 	/* Adjust data pointer */
859 	ncr_sc->sc_dataptr += ntrans;
860 	ncr_sc->sc_datalen -= ntrans;
861 
862 #ifdef	DEBUG
863 	if (si_debug & 2) {
864 		printf("%s: ntrans=0x%x\n", __func__, ntrans);
865 	}
866 #endif
867 
868 	/*
869 	 * After a read, we may need to clean-up
870 	 * "Left-over bytes" (yuck!)
871 	 */
872 	if (((dh->dh_flags & SIDH_OUT) == 0) &&
873 		((csr & SI_CSR_LOB) != 0)) {
874 		uint8_t *cp = ncr_sc->sc_dataptr;
875 		uint16_t bprh, bprl;
876 
877 		bprh = SIREG_READ(ncr_sc, SIREG_BPRH);
878 		bprl = SIREG_READ(ncr_sc, SIREG_BPRL);
879 
880 #ifdef DEBUG
881 		printf("si: got left-over bytes: bprh=%x, bprl=%x, csr=%x\n",
882 			bprh, bprl, csr);
883 #endif
884 
885 		if (csr & SI_CSR_BPCON) {
886 			/* have SI_CSR_BPCON */
887 			cp[-1] = (bprl & 0xff00) >> 8;
888 		} else {
889 			switch (csr & SI_CSR_LOB) {
890 			case SI_CSR_LOB_THREE:
891 				cp[-3] = (bprh & 0xff00) >> 8;
892 				cp[-2] = (bprh & 0x00ff);
893 				cp[-1] = (bprl & 0xff00) >> 8;
894 				break;
895 			case SI_CSR_LOB_TWO:
896 				cp[-2] = (bprh & 0xff00) >> 8;
897 				cp[-1] = (bprh & 0x00ff);
898 				break;
899 			case SI_CSR_LOB_ONE:
900 				cp[-1] = (bprh & 0xff00) >> 8;
901 				break;
902 			}
903 		}
904 	}
905 
906 out:
907 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, 0);
908 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, 0);
909 
910 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
911 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
912 
913 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, 0);
914 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, 0);
915 
916 	mode = NCR5380_READ(ncr_sc, sci_mode);
917 	/* Put SBIC back in PIO mode. */
918 	mode &= ~(SCI_MODE_DMA | SCI_MODE_DMA_IE);
919 	NCR5380_WRITE(ncr_sc, sci_mode, mode);
920 	NCR5380_WRITE(ncr_sc, sci_icmd, 0);
921 }
922