xref: /netbsd-src/sys/arch/sun3/dev/si.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: si.c,v 1.62 2008/04/28 20:23:37 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 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, and Gordon W. Ross.
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  * This file contains only the machine-dependent parts of the
34  * Sun3 SCSI driver.  (Autoconfig stuff and DMA functions.)
35  * The machine-independent parts are in ncr5380sbc.c
36  *
37  * Supported hardware includes:
38  * Sun SCSI-3 on OBIO (Sun3/50,Sun3/60)
39  * Sun SCSI-3 on VME (Sun3/160,Sun3/260)
40  *
41  * Could be made to support the Sun3/E if someone wanted to.
42  *
43  * Note:  Both supported variants of the Sun SCSI-3 adapter have
44  * some really unusual "features" for this driver to deal with,
45  * generally related to the DMA engine.  The OBIO variant will
46  * ignore any attempt to write the FIFO count register while the
47  * SCSI bus is in DATA_IN or DATA_OUT phase.  This is dealt with
48  * by setting the FIFO count early in COMMAND or MSG_IN phase.
49  *
50  * The VME variant has a bit to enable or disable the DMA engine,
51  * but that bit also gates the interrupt line from the NCR5380!
52  * Therefore, in order to get any interrupt from the 5380, (i.e.
53  * for reselect) one must clear the DMA engine transfer count and
54  * then enable DMA.  This has the further complication that you
55  * CAN NOT touch the NCR5380 while the DMA enable bit is set, so
56  * we have to turn DMA back off before we even look at the 5380.
57  *
58  * What wonderfully whacky hardware this is!
59  *
60  * Credits, history:
61  *
62  * David Jones wrote the initial version of this module, which
63  * included support for the VME adapter only. (no reselection).
64  *
65  * Gordon Ross added support for the OBIO adapter, and re-worked
66  * both the VME and OBIO code to support disconnect/reselect.
67  * (Required figuring out the hardware "features" noted above.)
68  *
69  * The autoconfiguration boilerplate came from Adam Glass.
70  */
71 
72 #include <sys/cdefs.h>
73 __KERNEL_RCSID(0, "$NetBSD: si.c,v 1.62 2008/04/28 20:23:37 martin Exp $");
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 <dev/scsipi/scsi_all.h>
86 #include <dev/scsipi/scsipi_all.h>
87 #include <dev/scsipi/scsipi_debug.h>
88 #include <dev/scsipi/scsiconf.h>
89 
90 #include <machine/autoconf.h>
91 #include <machine/bus.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 #endif
111 
112 /* How long to wait for DMA before declaring an error. */
113 int si_dma_intr_timo = 500;	/* ticks (sec. X 100) */
114 
115 static void	si_minphys(struct buf *);
116 
117 /*
118  * New-style autoconfig attachment. The cfattach
119  * structures are in si_obio.c and si_vme.c
120  */
121 
122 void
123 si_attach(struct si_softc *sc)
124 {
125 	struct ncr5380_softc *ncr_sc = &sc->ncr_sc;
126 	volatile struct si_regs *regs = sc->sc_regs;
127 	int i;
128 
129 	/*
130 	 * Support the "options" (config file flags).
131 	 * Disconnect/reselect is a per-target mask.
132 	 * Interrupts and DMA are per-controller.
133 	 */
134 	ncr_sc->sc_no_disconnect =
135 	    (sc->sc_options & SI_NO_DISCONNECT);
136 	ncr_sc->sc_parity_disable =
137 	    (sc->sc_options & SI_NO_PARITY_CHK) >> 8;
138 	if (sc->sc_options & SI_FORCE_POLLING)
139 		ncr_sc->sc_flags |= NCR5380_FORCE_POLLING;
140 
141 #if 1	/* XXX - Temporary */
142 	/* XXX - In case we think DMA is completely broken... */
143 	if (sc->sc_options & SI_DISABLE_DMA) {
144 		/* Override this function pointer. */
145 		ncr_sc->sc_dma_alloc = NULL;
146 	}
147 #endif
148 	ncr_sc->sc_min_dma_len = MIN_DMA_LEN;
149 
150 	/*
151 	 * Initialize fields used by the MI code
152 	 */
153 	ncr_sc->sci_r0 = &regs->sci.sci_r0;
154 	ncr_sc->sci_r1 = &regs->sci.sci_r1;
155 	ncr_sc->sci_r2 = &regs->sci.sci_r2;
156 	ncr_sc->sci_r3 = &regs->sci.sci_r3;
157 	ncr_sc->sci_r4 = &regs->sci.sci_r4;
158 	ncr_sc->sci_r5 = &regs->sci.sci_r5;
159 	ncr_sc->sci_r6 = &regs->sci.sci_r6;
160 	ncr_sc->sci_r7 = &regs->sci.sci_r7;
161 
162 	ncr_sc->sc_rev = NCR_VARIANT_NCR5380;
163 
164 	/*
165 	 * Allocate DMA handles.
166 	 */
167 	i = SCI_OPENINGS * sizeof(struct si_dma_handle);
168 	sc->sc_dma = (struct si_dma_handle *)
169 		malloc(i, M_DEVBUF, M_WAITOK);
170 	if (sc->sc_dma == NULL)
171 		panic("si: dvma_malloc failed");
172 	for (i = 0; i < SCI_OPENINGS; i++)
173 		sc->sc_dma[i].dh_flags = 0;
174 
175 	ncr_sc->sc_channel.chan_id = 7;
176 	ncr_sc->sc_adapter.adapt_minphys = si_minphys;
177 
178 	/*
179 	 *  Initialize si board itself.
180 	 */
181 	ncr5380_attach(ncr_sc);
182 }
183 
184 static void
185 si_minphys(struct buf *bp)
186 {
187 
188 	if (bp->b_bcount > MAX_DMA_LEN) {
189 #ifdef	DEBUG
190 		if (si_debug) {
191 			printf("%s len = 0x%x.\n", __func__, bp->b_bcount);
192 			Debugger();
193 		}
194 #endif
195 		bp->b_bcount = MAX_DMA_LEN;
196 	}
197 	minphys(bp);
198 }
199 
200 
201 #define CSR_WANT (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
202 	SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR )
203 
204 int
205 si_intr(void *arg)
206 {
207 	struct si_softc *sc = arg;
208 	volatile struct si_regs *si = sc->sc_regs;
209 	int dma_error, claimed;
210 	u_short csr;
211 
212 	claimed = 0;
213 	dma_error = 0;
214 
215 	/* SBC interrupt? DMA interrupt? */
216 	csr = si->si_csr;
217 	NCR_TRACE("si_intr: csr=0x%x\n", csr);
218 
219 	if (csr & SI_CSR_DMA_CONFLICT) {
220 		dma_error |= SI_CSR_DMA_CONFLICT;
221 		printf("%s: DMA conflict\n", __func__);
222 	}
223 	if (csr & SI_CSR_DMA_BUS_ERR) {
224 		dma_error |= SI_CSR_DMA_BUS_ERR;
225 		printf("%s: DMA bus error\n", __func__);
226 	}
227 	if (dma_error) {
228 		if (sc->ncr_sc.sc_state & NCR_DOINGDMA)
229 			sc->ncr_sc.sc_state |= NCR_ABORTING;
230 		/* Make sure we will call the main isr. */
231 		csr |= SI_CSR_DMA_IP;
232 	}
233 
234 	if (csr & (SI_CSR_SBC_IP | SI_CSR_DMA_IP)) {
235 		claimed = ncr5380_intr(&sc->ncr_sc);
236 #ifdef	DEBUG
237 		if (!claimed) {
238 			printf("%s: spurious from SBC\n", __func__);
239 			if (si_debug & 4)
240 				Debugger();	/* XXX */
241 		}
242 #endif
243 		/* Yes, we DID cause this interrupt. */
244 		claimed = 1;
245 	}
246 
247 	return claimed;
248 }
249 
250 
251 /*****************************************************************
252  * Common functions for DMA
253  ****************************************************************/
254 
255 /*
256  * Allocate a DMA handle and put it in sc->sc_dma.  Prepare
257  * for DMA transfer.  On the Sun3, this means mapping the buffer
258  * into DVMA space.  dvma_mapin() flushes the cache for us.
259  */
260 void
261 si_dma_alloc(struct ncr5380_softc *ncr_sc)
262 {
263 	struct si_softc *sc = (struct si_softc *)ncr_sc;
264 	struct sci_req *sr = ncr_sc->sc_current;
265 	struct scsipi_xfer *xs = sr->sr_xs;
266 	struct si_dma_handle *dh;
267 	int i, xlen;
268 	void *addr;
269 
270 #ifdef	DIAGNOSTIC
271 	if (sr->sr_dma_hand != NULL)
272 		panic("%s: already have DMA handle", __func__);
273 #endif
274 
275 	addr = ncr_sc->sc_dataptr;
276 	xlen = ncr_sc->sc_datalen;
277 
278 	/* If the DMA start addr is misaligned then do PIO */
279 	if (((vaddr_t)addr & 1) || (xlen & 1)) {
280 		printf("%s: misaligned.\n", __func__);
281 		return;
282 	}
283 
284 	/* Make sure our caller checked sc_min_dma_len. */
285 	if (xlen < MIN_DMA_LEN)
286 		panic("%s: xlen=0x%x", __func__, xlen);
287 
288 	/*
289 	 * Never attempt single transfers of more than 63k, because
290 	 * our count register may be only 16 bits (an OBIO adapter).
291 	 * This should never happen since already bounded by minphys().
292 	 * XXX - Should just segment these...
293 	 */
294 	if (xlen > MAX_DMA_LEN) {
295 		printf("%s: excessive xlen=0x%x\n", __func__, xlen);
296 		Debugger();
297 		ncr_sc->sc_datalen = xlen = MAX_DMA_LEN;
298 	}
299 
300 	/* Find free DMA handle.  Guaranteed to find one since we have
301 	   as many DMA handles as the driver has processes. */
302 	for (i = 0; i < SCI_OPENINGS; i++) {
303 		if ((sc->sc_dma[i].dh_flags & SIDH_BUSY) == 0)
304 			goto found;
305 	}
306 	panic("si: no free DMA handles.");
307 found:
308 
309 	dh = &sc->sc_dma[i];
310 	dh->dh_flags = SIDH_BUSY;
311 
312 	if (bus_dmamap_load(sc->sc_dmat, sc->sc_dmap, addr, xlen, NULL,
313 	    BUS_DMA_NOWAIT) != 0)
314 		panic("%s: can't load dmamap", device_xname(ncr_sc->sc_dev));
315 	dh->dh_dmaaddr = sc->sc_dmap->dm_segs[0].ds_addr;
316 	dh->dh_dmalen  = xlen;
317 
318 	/* Copy the "write" flag for convenience. */
319 	if (xs->xs_control & XS_CTL_DATA_OUT)
320 		dh->dh_flags |= SIDH_OUT;
321 
322 	bus_dmamap_sync(sc->sc_dmat, sc->sc_dmap, 0, dh->dh_dmalen,
323 	    (dh->dh_flags & SIDH_OUT) == 0 ?
324 	    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
325 
326 #if 0
327 	/*
328 	 * Some machines might not need to remap B_PHYS buffers.
329 	 * The sun3 does not map B_PHYS buffers into DVMA space,
330 	 * (they are mapped into normal KV space) so on the sun3
331 	 * we must always remap to a DVMA address here. Re-map is
332 	 * cheap anyway, because it's done by segments, not pages.
333 	 */
334 	if (xs->bp && (xs->bp->b_flags & B_PHYS))
335 		dh->dh_flags |= SIDH_PHYS;
336 #endif
337 
338 	/* success */
339 	sr->sr_dma_hand = dh;
340 
341 	return;
342 }
343 
344 
345 void
346 si_dma_free(struct ncr5380_softc *ncr_sc)
347 {
348 	struct si_softc *sc = (struct si_softc *)ncr_sc;
349 	struct sci_req *sr = ncr_sc->sc_current;
350 	struct si_dma_handle *dh = sr->sr_dma_hand;
351 
352 #ifdef	DIAGNOSTIC
353 	if (dh == NULL)
354 		panic("%s: no DMA handle", __func__);
355 #endif
356 
357 	if (ncr_sc->sc_state & NCR_DOINGDMA)
358 		panic("%s: free while in progress", __func__);
359 
360 	if (dh->dh_flags & SIDH_BUSY) {
361 		bus_dmamap_sync(sc->sc_dmat, sc->sc_dmap, 0, dh->dh_dmalen,
362 		    (dh->dh_flags & SIDH_OUT) == 0 ?
363 		    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
364 		bus_dmamap_unload(sc->sc_dmat, sc->sc_dmap);
365 		dh->dh_dmaaddr = 0;
366 		dh->dh_flags = 0;
367 	}
368 	sr->sr_dma_hand = NULL;
369 }
370 
371 
372 #define	CSR_MASK (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
373 		SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR)
374 #define	POLL_TIMO	50000	/* X100 = 5 sec. */
375 
376 /*
377  * Poll (spin-wait) for DMA completion.
378  * Called right after xx_dma_start(), and
379  * xx_dma_stop() will be called next.
380  * Same for either VME or OBIO.
381  */
382 void
383 si_dma_poll(struct ncr5380_softc *ncr_sc)
384 {
385 	struct si_softc *sc = (struct si_softc *)ncr_sc;
386 	struct sci_req *sr = ncr_sc->sc_current;
387 	volatile struct si_regs *si = sc->sc_regs;
388 	int tmo;
389 
390 	/* Make sure DMA started successfully. */
391 	if (ncr_sc->sc_state & NCR_ABORTING)
392 		return;
393 
394 	/*
395 	 * XXX: The Sun driver waits for ~SI_CSR_DMA_ACTIVE here
396 	 * XXX: (on obio) or even worse (on vme) a 10mS. delay!
397 	 * XXX: I really doubt that is necessary...
398 	 */
399 
400 	/* Wait for any "DMA complete" or error bits. */
401 	tmo = POLL_TIMO;
402 	for (;;) {
403 		if (si->si_csr & CSR_MASK)
404 			break;
405 		if (--tmo <= 0) {
406 			printf("si: DMA timeout (while polling)\n");
407 			/* Indicate timeout as MI code would. */
408 			sr->sr_flags |= SR_OVERDUE;
409 			break;
410 		}
411 		delay(100);
412 	}
413 	NCR_TRACE("si_dma_poll: waited %d\n",
414 			  POLL_TIMO - tmo);
415 
416 #ifdef	DEBUG
417 	if (si_debug & 2) {
418 		printf("%s: done, csr=0x%x\n", __func__, si->si_csr);
419 	}
420 #endif
421 }
422