xref: /netbsd-src/sys/arch/sun3/dev/si.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: si.c,v 1.30 1996/10/30 00:24:38 gwr Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 David Jones, Gordon W. Ross
5  * Copyright (c) 1994 Adam Glass
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the authors may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  * 4. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by
21  *      Adam Glass, David Jones, and Gordon Ross
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 /*
36  * This file contains only the machine-dependent parts of the
37  * Sun3 SCSI driver.  (Autoconfig stuff and DMA functions.)
38  * The machine-independent parts are in ncr5380sbc.c
39  *
40  * Supported hardware includes:
41  * Sun SCSI-3 on OBIO (Sun3/50,Sun3/60)
42  * Sun SCSI-3 on VME (Sun3/160,Sun3/260)
43  *
44  * Could be made to support the Sun3/E if someone wanted to.
45  *
46  * Note:  Both supported variants of the Sun SCSI-3 adapter have
47  * some really unusual "features" for this driver to deal with,
48  * generally related to the DMA engine.  The OBIO variant will
49  * ignore any attempt to write the FIFO count register while the
50  * SCSI bus is in DATA_IN or DATA_OUT phase.  This is dealt with
51  * by setting the FIFO count early in COMMAND or MSG_IN phase.
52  *
53  * The VME variant has a bit to enable or disable the DMA engine,
54  * but that bit also gates the interrupt line from the NCR5380!
55  * Therefore, in order to get any interrupt from the 5380, (i.e.
56  * for reselect) one must clear the DMA engine transfer count and
57  * then enable DMA.  This has the further complication that you
58  * CAN NOT touch the NCR5380 while the DMA enable bit is set, so
59  * we have to turn DMA back off before we even look at the 5380.
60  *
61  * What wonderfully whacky hardware this is!
62  *
63  * Credits, history:
64  *
65  * David Jones wrote the initial version of this module, which
66  * included support for the VME adapter only. (no reselection).
67  *
68  * Gordon Ross added support for the OBIO adapter, and re-worked
69  * both the VME and OBIO code to support disconnect/reselect.
70  * (Required figuring out the hardware "features" noted above.)
71  *
72  * The autoconfiguration boilerplate came from Adam Glass.
73  */
74 
75 #include <sys/param.h>
76 #include <sys/systm.h>
77 #include <sys/errno.h>
78 #include <sys/kernel.h>
79 #include <sys/malloc.h>
80 #include <sys/device.h>
81 #include <sys/buf.h>
82 #include <sys/proc.h>
83 #include <sys/user.h>
84 
85 #include <scsi/scsi_all.h>
86 #include <scsi/scsi_debug.h>
87 #include <scsi/scsiconf.h>
88 
89 #include <machine/autoconf.h>
90 #include <machine/isr.h>
91 #include <machine/obio.h>
92 #include <machine/dvma.h>
93 
94 #define DEBUG XXX
95 
96 #include <dev/ic/ncr5380reg.h>
97 #include <dev/ic/ncr5380var.h>
98 
99 #include "sireg.h"
100 #include "sivar.h"
101 
102 /*
103  * Transfers smaller than this are done using PIO
104  * (on assumption they're not worth DMA overhead)
105  */
106 #define	MIN_DMA_LEN 128
107 
108 int si_debug = 0;
109 #ifdef	DEBUG
110 static int si_link_flags = 0 /* | SDEV_DB2 */ ;
111 #endif
112 
113 /* How long to wait for DMA before declaring an error. */
114 int si_dma_intr_timo = 500;	/* ticks (sec. X 100) */
115 
116 static void	si_minphys __P((struct buf *));
117 
118 static struct scsi_adapter	si_ops = {
119 	ncr5380_scsi_cmd,		/* scsi_cmd()		*/
120 	si_minphys,			/* scsi_minphys()	*/
121 	NULL,				/* open_target_lu()	*/
122 	NULL,				/* close_target_lu()	*/
123 };
124 
125 /* This is copied from julian's bt driver */
126 /* "so we have a default dev struct for our link struct." */
127 static struct scsi_device si_dev = {
128 	NULL,		/* Use default error handler.	    */
129 	NULL,		/* Use default start handler.		*/
130 	NULL,		/* Use default async handler.	    */
131 	NULL,		/* Use default "done" routine.	    */
132 };
133 
134 /*
135  * New-style autoconfig attachment. The cfattach
136  * structures are in si_obio.c and si_vme.c
137  */
138 
139 struct cfdriver si_cd = {
140 	NULL, "si", DV_DULL
141 };
142 
143 
144 void
145 si_attach(sc)
146 	struct si_softc *sc;
147 {
148 	struct ncr5380_softc *ncr_sc = (void *)sc;
149 	volatile struct si_regs *regs = sc->sc_regs;
150 	int i;
151 
152 	/*
153 	 * Support the "options" (config file flags).
154 	 */
155 	if ((sc->sc_options & SI_DO_RESELECT) != 0)
156 		ncr_sc->sc_flags |= NCR5380_PERMIT_RESELECT;
157 	if ((sc->sc_options & SI_DMA_INTR) == 0)
158 		ncr_sc->sc_flags |= NCR5380_FORCE_POLLING;
159 #if 1	/* XXX - Temporary */
160 	/* XXX - In case we think DMA is completely broken... */
161 	if ((sc->sc_options & SI_ENABLE_DMA) == 0) {
162 		/* Override this function pointer. */
163 		ncr_sc->sc_dma_alloc = NULL;
164 	}
165 #endif
166 	ncr_sc->sc_min_dma_len = MIN_DMA_LEN;
167 
168 	/*
169 	 * Fill in the prototype scsi_link.
170 	 */
171 	ncr_sc->sc_link.channel = SCSI_CHANNEL_ONLY_ONE;
172 	ncr_sc->sc_link.adapter_softc = sc;
173 	ncr_sc->sc_link.adapter_target = 7;
174 	ncr_sc->sc_link.adapter = &si_ops;
175 	ncr_sc->sc_link.device = &si_dev;
176 
177 #ifdef	DEBUG
178 	if (si_debug)
179 		printf("si: Set TheSoftC=%x TheRegs=%x\n", sc, regs);
180 	ncr_sc->sc_link.flags |= si_link_flags;
181 #endif
182 
183 	/*
184 	 * Initialize fields used by the MI code
185 	 */
186 	ncr_sc->sci_r0 = &regs->sci.sci_r0;
187 	ncr_sc->sci_r1 = &regs->sci.sci_r1;
188 	ncr_sc->sci_r2 = &regs->sci.sci_r2;
189 	ncr_sc->sci_r3 = &regs->sci.sci_r3;
190 	ncr_sc->sci_r4 = &regs->sci.sci_r4;
191 	ncr_sc->sci_r5 = &regs->sci.sci_r5;
192 	ncr_sc->sci_r6 = &regs->sci.sci_r6;
193 	ncr_sc->sci_r7 = &regs->sci.sci_r7;
194 
195 	/*
196 	 * Allocate DMA handles.
197 	 */
198 	i = SCI_OPENINGS * sizeof(struct si_dma_handle);
199 	sc->sc_dma = (struct si_dma_handle *)
200 		malloc(i, M_DEVBUF, M_WAITOK);
201 	if (sc->sc_dma == NULL)
202 		panic("si: dvma_malloc failed\n");
203 	for (i = 0; i < SCI_OPENINGS; i++)
204 		sc->sc_dma[i].dh_flags = 0;
205 
206 	/*
207 	 *  Initialize si board itself.
208 	 */
209 	si_reset_adapter(ncr_sc);
210 	ncr5380_init(ncr_sc);
211 	ncr5380_reset_scsibus(ncr_sc);
212 	config_found(&(ncr_sc->sc_dev), &(ncr_sc->sc_link), scsiprint);
213 }
214 
215 static void
216 si_minphys(struct buf *bp)
217 {
218 	if (bp->b_bcount > MAX_DMA_LEN) {
219 #ifdef	DEBUG
220 		if (si_debug) {
221 			printf("si_minphys len = 0x%x.\n", bp->b_bcount);
222 			Debugger();
223 		}
224 #endif
225 		bp->b_bcount = MAX_DMA_LEN;
226 	}
227 	return (minphys(bp));
228 }
229 
230 
231 #define CSR_WANT (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
232 	SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR )
233 
234 int
235 si_intr(void *arg)
236 {
237 	struct si_softc *sc = arg;
238 	volatile struct si_regs *si = sc->sc_regs;
239 	int dma_error, claimed;
240 	u_short csr;
241 
242 	claimed = 0;
243 	dma_error = 0;
244 
245 	/* SBC interrupt? DMA interrupt? */
246 	csr = si->si_csr;
247 	NCR_TRACE("si_intr: csr=0x%x\n", csr);
248 
249 	if (csr & SI_CSR_DMA_CONFLICT) {
250 		dma_error |= SI_CSR_DMA_CONFLICT;
251 		printf("si_intr: DMA conflict\n");
252 	}
253 	if (csr & SI_CSR_DMA_BUS_ERR) {
254 		dma_error |= SI_CSR_DMA_BUS_ERR;
255 		printf("si_intr: DMA bus error\n");
256 	}
257 	if (dma_error) {
258 		if (sc->ncr_sc.sc_state & NCR_DOINGDMA)
259 			sc->ncr_sc.sc_state |= NCR_ABORTING;
260 		/* Make sure we will call the main isr. */
261 		csr |= SI_CSR_DMA_IP;
262 	}
263 
264 	if (csr & (SI_CSR_SBC_IP | SI_CSR_DMA_IP)) {
265 		claimed = ncr5380_intr(&sc->ncr_sc);
266 #ifdef	DEBUG
267 		if (!claimed) {
268 			printf("si_intr: spurious from SBC\n");
269 			if (si_debug & 4) {
270 				Debugger();	/* XXX */
271 			}
272 		}
273 #endif
274 	}
275 
276 	return (claimed);
277 }
278 
279 
280 void
281 si_reset_adapter(struct ncr5380_softc *ncr_sc)
282 {
283 	struct si_softc *sc = (struct si_softc *)ncr_sc;
284 	volatile struct si_regs *si = sc->sc_regs;
285 
286 #ifdef	DEBUG
287 	if (si_debug) {
288 		printf("si_reset_adapter\n");
289 	}
290 #endif
291 
292 	/*
293 	 * The SCSI3 controller has an 8K FIFO to buffer data between the
294 	 * 5380 and the DMA.  Make sure it starts out empty.
295 	 *
296 	 * The reset bits in the CSR are active low.
297 	 */
298 	si->si_csr = 0;
299 	delay(10);
300 	si->si_csr = SI_CSR_FIFO_RES | SI_CSR_SCSI_RES | SI_CSR_INTR_EN;
301 	delay(10);
302 	si->fifo_count = 0;
303 
304 	if (sc->sc_adapter_type == BUS_VME16) {
305 		si->dma_addrh = 0;
306 		si->dma_addrl = 0;
307 		si->dma_counth = 0;
308 		si->dma_countl = 0;
309 		si->si_iv_am = sc->sc_adapter_iv_am;
310 		si->fifo_cnt_hi = 0;
311 	}
312 
313 	SCI_CLR_INTR(ncr_sc);
314 }
315 
316 
317 /*****************************************************************
318  * Common functions for DMA
319  ****************************************************************/
320 
321 /*
322  * Allocate a DMA handle and put it in sc->sc_dma.  Prepare
323  * for DMA transfer.  On the Sun3, this means mapping the buffer
324  * into DVMA space.  dvma_mapin() flushes the cache for us.
325  */
326 void
327 si_dma_alloc(ncr_sc)
328 	struct ncr5380_softc *ncr_sc;
329 {
330 	struct si_softc *sc = (struct si_softc *)ncr_sc;
331 	struct sci_req *sr = ncr_sc->sc_current;
332 	struct scsi_xfer *xs = sr->sr_xs;
333 	struct si_dma_handle *dh;
334 	int i, xlen;
335 	u_long addr;
336 
337 #ifdef	DIAGNOSTIC
338 	if (sr->sr_dma_hand != NULL)
339 		panic("si_dma_alloc: already have DMA handle");
340 #endif
341 
342 	addr = (u_long) ncr_sc->sc_dataptr;
343 	xlen = ncr_sc->sc_datalen;
344 
345 	/* If the DMA start addr is misaligned then do PIO */
346 	if ((addr & 1) || (xlen & 1)) {
347 		printf("si_dma_alloc: misaligned.\n");
348 		return;
349 	}
350 
351 	/* Make sure our caller checked sc_min_dma_len. */
352 	if (xlen < MIN_DMA_LEN)
353 		panic("si_dma_alloc: xlen=0x%x\n", xlen);
354 
355 	/*
356 	 * Never attempt single transfers of more than 63k, because
357 	 * our count register may be only 16 bits (an OBIO adapter).
358 	 * This should never happen since already bounded by minphys().
359 	 * XXX - Should just segment these...
360 	 */
361 	if (xlen > MAX_DMA_LEN) {
362 		printf("si_dma_alloc: excessive xlen=0x%x\n", xlen);
363 		Debugger();
364 		ncr_sc->sc_datalen = xlen = MAX_DMA_LEN;
365 	}
366 
367 	/* Find free DMA handle.  Guaranteed to find one since we have
368 	   as many DMA handles as the driver has processes. */
369 	for (i = 0; i < SCI_OPENINGS; i++) {
370 		if ((sc->sc_dma[i].dh_flags & SIDH_BUSY) == 0)
371 			goto found;
372 	}
373 	panic("si: no free DMA handles.");
374 found:
375 
376 	dh = &sc->sc_dma[i];
377 	dh->dh_flags = SIDH_BUSY;
378 	dh->dh_addr = (u_char*) addr;
379 	dh->dh_maplen  = xlen;
380 	dh->dh_dvma = 0;
381 
382 	/* Copy the "write" flag for convenience. */
383 	if (xs->flags & SCSI_DATA_OUT)
384 		dh->dh_flags |= SIDH_OUT;
385 
386 #if 0
387 	/*
388 	 * Some machines might not need to remap B_PHYS buffers.
389 	 * The sun3 does not map B_PHYS buffers into DVMA space,
390 	 * (they are mapped into normal KV space) so on the sun3
391 	 * we must always remap to a DVMA address here. Re-map is
392 	 * cheap anyway, because it's done by segments, not pages.
393 	 */
394 	if (xs->bp && (xs->bp->b_flags & B_PHYS))
395 		dh->dh_flags |= SIDH_PHYS;
396 #endif
397 
398 	dh->dh_dvma = (u_long) dvma_mapin((char *)addr, xlen);
399 	if (!dh->dh_dvma) {
400 		/* Can't remap segment */
401 		printf("si_dma_alloc: can't remap %x/%x\n",
402 			dh->dh_addr, dh->dh_maplen);
403 		dh->dh_flags = 0;
404 		return;
405 	}
406 
407 	/* success */
408 	sr->sr_dma_hand = dh;
409 
410 	return;
411 }
412 
413 
414 void
415 si_dma_free(ncr_sc)
416 	struct ncr5380_softc *ncr_sc;
417 {
418 	struct sci_req *sr = ncr_sc->sc_current;
419 	struct si_dma_handle *dh = sr->sr_dma_hand;
420 
421 #ifdef	DIAGNOSTIC
422 	if (dh == NULL)
423 		panic("si_dma_free: no DMA handle");
424 #endif
425 
426 	if (ncr_sc->sc_state & NCR_DOINGDMA)
427 		panic("si_dma_free: free while in progress");
428 
429 	if (dh->dh_flags & SIDH_BUSY) {
430 		/* XXX - Should separate allocation and mapping. */
431 		/* Give back the DVMA space. */
432 		dvma_mapout((caddr_t)dh->dh_dvma, dh->dh_maplen);
433 		dh->dh_dvma = 0;
434 		dh->dh_flags = 0;
435 	}
436 	sr->sr_dma_hand = NULL;
437 }
438 
439 
440 #define	CSR_MASK (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
441 		SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR)
442 #define	POLL_TIMO	50000	/* X100 = 5 sec. */
443 
444 /*
445  * Poll (spin-wait) for DMA completion.
446  * Called right after xx_dma_start(), and
447  * xx_dma_stop() will be called next.
448  * Same for either VME or OBIO.
449  */
450 void
451 si_dma_poll(ncr_sc)
452 	struct ncr5380_softc *ncr_sc;
453 {
454 	struct si_softc *sc = (struct si_softc *)ncr_sc;
455 	struct sci_req *sr = ncr_sc->sc_current;
456 	struct si_dma_handle *dh = sr->sr_dma_hand;
457 	volatile struct si_regs *si = sc->sc_regs;
458 	int tmo;
459 
460 	/* Make sure DMA started successfully. */
461 	if (ncr_sc->sc_state & NCR_ABORTING)
462 		return;
463 
464 	/*
465 	 * XXX: The Sun driver waits for ~SI_CSR_DMA_ACTIVE here
466 	 * XXX: (on obio) or even worse (on vme) a 10mS. delay!
467 	 * XXX: I really doubt that is necessary...
468 	 */
469 
470 	/* Wait for any "dma complete" or error bits. */
471 	tmo = POLL_TIMO;
472 	for (;;) {
473 		if (si->si_csr & CSR_MASK)
474 			break;
475 		if (--tmo <= 0) {
476 			printf("si: DMA timeout (while polling)\n");
477 			/* Indicate timeout as MI code would. */
478 			sr->sr_flags |= SR_OVERDUE;
479 			break;
480 		}
481 		delay(100);
482 	}
483 	NCR_TRACE("si_dma_poll: waited %d\n",
484 			  POLL_TIMO - tmo);
485 
486 #ifdef	DEBUG
487 	if (si_debug & 2) {
488 		printf("si_dma_poll: done, csr=0x%x\n", si->si_csr);
489 	}
490 #endif
491 }
492 
493