xref: /netbsd-src/sys/arch/sun3/dev/dma.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: dma.c,v 1.19 2007/03/04 13:59:47 tsutsui Exp $ */
2 
3 /*
4  * Copyright (c) 1994 Paul Kranenburg.  All rights reserved.
5  * Copyright (c) 1994 Peter Galbavy.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Peter Galbavy.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: dma.c,v 1.19 2007/03/04 13:59:47 tsutsui Exp $");
35 
36 #include <sys/types.h>
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/errno.h>
41 #include <sys/device.h>
42 #include <sys/malloc.h>
43 
44 #include <machine/autoconf.h>
45 #include <machine/dvma.h>
46 
47 #include <dev/scsipi/scsi_all.h>
48 #include <dev/scsipi/scsipi_all.h>
49 #include <dev/scsipi/scsiconf.h>
50 
51 #include <dev/ic/ncr53c9xreg.h>
52 #include <dev/ic/ncr53c9xvar.h>
53 
54 #include <sun3/dev/dmareg.h>
55 #include <sun3/dev/dmavar.h>
56 
57 #define MAX_DMA_SZ	0x01000000	/* 16MB */
58 
59 static int	dmamatch (struct device *, struct cfdata *, void *);
60 static void	dmaattach(struct device *, struct device *, void *);
61 
62 CFATTACH_DECL(dma, sizeof(struct dma_softc),
63     dmamatch, dmaattach, NULL, NULL);
64 
65 extern struct cfdriver dma_cd;
66 
67 static int
68 dmamatch(struct device *parent, struct cfdata *cf, void *aux)
69 {
70 	struct confargs *ca = aux;
71 
72 	/*
73 	 * Check for the DMA registers.
74 	 */
75 	if (bus_peek(ca->ca_bustype, ca->ca_paddr, 4) == -1)
76 		return (0);
77 
78 	/* If default ipl, fill it in. */
79 	if (ca->ca_intpri == -1)
80 		ca->ca_intpri = 2;
81 
82 	return (1);
83 }
84 
85 static void
86 dmaattach(struct device *parent, struct device *self, void *aux)
87 {
88 	struct confargs *ca = aux;
89 	struct dma_softc *sc = (void *)self;
90 	int id;
91 
92 #if 0
93 	/* indirect functions */
94 	sc->intr = espdmaintr;
95 	sc->setup = dma_setup;
96 	sc->reset = dma_reset;
97 #endif
98 
99 	/*
100 	 * Map in the registers.
101 	 */
102 	sc->sc_bst = ca->ca_bustag;
103 	sc->sc_dmatag = ca->ca_dmatag;
104 	if (bus_space_map(sc->sc_bst, ca->ca_paddr, DMAREG_SIZE,
105 	    0, &sc->sc_bsh) != 0) {
106 		printf(": can't map register\n");
107 		return;
108 	}
109 	/*
110 	 * Allocate dmamap.
111 	 */
112 	if (bus_dmamap_create(sc->sc_dmatag, MAXPHYS, 1, MAXPHYS,
113 	    0, BUS_DMA_NOWAIT, &sc->sc_dmamap) != 0) {
114 		printf(": can't create DMA map\n");
115 		return;
116 	}
117 
118 	sc->sc_rev = DMA_GCSR(sc) & D_DEV_ID;
119 	id = (sc->sc_rev >> 28) & 0xf;
120 	printf(": rev %d\n", id);
121 
122 	/*
123 	 * Make sure the DMA chip is supported revision.
124 	 * The Sun3/80 used only the old rev zero chip,
125 	 * so the initialization has been simplified.
126 	 */
127 	switch (sc->sc_rev) {
128 	case DMAREV_0:
129 	case DMAREV_1:
130 		break;
131 	default:
132 		panic("unsupported dma rev");
133 	}
134 }
135 
136 /*
137  * This is called by espattach to get our softc.
138  */
139 struct dma_softc *
140 espdmafind(int unit)
141 {
142 	if (unit < 0 || unit >= dma_cd.cd_ndevs ||
143 		dma_cd.cd_devs[unit] == NULL)
144 		panic("no dma");
145 	return (dma_cd.cd_devs[unit]);
146 }
147 
148 #define DMAWAIT(SC, COND, MSG, DONTPANIC) do if (COND) {		\
149 	int count = 100000;						\
150 	while ((COND) && --count > 0)					\
151 		DELAY(5);						\
152 	if (count == 0) {						\
153 		printf("%s: line %d: CSR = 0x%x\n",			\
154 			__FILE__, __LINE__, DMA_GCSR(SC));		\
155 		if (DONTPANIC)						\
156 			printf(MSG);					\
157 		else							\
158 			panic(MSG);					\
159 	}								\
160 } while (/* CONSTCOND */0)
161 
162 #define DMA_DRAIN(sc, dontpanic) do {					\
163 	uint32_t _csr;							\
164 	/*								\
165 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
166 	 *     and "drain" bits while it is still thinking about a	\
167 	 *     request.							\
168 	 * other revs: D_R_PEND bit reads as 0				\
169 	 */								\
170 	DMAWAIT(sc, DMA_GCSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
171 	/*								\
172 	 * Select drain bit (always rev 0,1)				\
173 	 * also clears errors and D_TC flag				\
174 	 */								\
175 	_csr = DMA_GCSR(sc);						\
176 	_csr |= D_DRAIN;						\
177 	DMA_SCSR(sc, _csr);						\
178 	/*								\
179 	 * Wait for draining to finish					\
180 	 */								\
181 	DMAWAIT(sc, DMA_GCSR(sc) & D_PACKCNT, "DRAINING", dontpanic);	\
182 } while (/* CONSTCOND */0)
183 
184 #define DMA_FLUSH(sc, dontpanic) do {					\
185 	uint32_t _csr;							\
186 	/*								\
187 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
188 	 *     and "drain" bits while it is still thinking about a	\
189 	 *     request.							\
190 	 * other revs: D_R_PEND bit reads as 0				\
191 	 */								\
192 	DMAWAIT(sc, DMA_GCSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
193 	_csr = DMA_GCSR(sc);						\
194 	_csr &= ~(D_WRITE|D_EN_DMA);					\
195 	DMA_SCSR(sc, _csr);						\
196 	_csr |= D_FLUSH;						\
197 	DMA_SCSR(sc, _csr);						\
198 } while (/* CONSTCOND */0)
199 
200 void
201 dma_reset(struct dma_softc *sc)
202 {
203 	uint32_t csr;
204 
205 	if (sc->sc_dmamap->dm_nsegs > 0)
206 		bus_dmamap_unload(sc->sc_dmatag, sc->sc_dmamap);
207 
208 	DMA_FLUSH(sc, 1);
209 	csr = DMA_GCSR(sc);
210 
211 	csr |= D_RESET;			/* reset DMA */
212 	DMA_SCSR(sc, csr);
213 	DELAY(200);			/* what should this be ? */
214 
215 	/*DMAWAIT1(sc); why was this here? */
216 	csr = DMA_GCSR(sc);
217 	csr &= ~D_RESET;		/* de-assert reset line */
218 	DMA_SCSR(sc, csr);
219 	DELAY(5);			/* allow a few ticks to settle */
220 
221 	/*
222 	 * Get transfer burst size from (?) and plug it into the
223 	 * controller registers. This is needed on the Sun4m...
224 	 * Do we need it too?  Apparently not, because the 3/80
225 	 * always has the old, REV zero DMA chip.
226 	 */
227 	csr = DMA_GCSR(sc);
228 	csr |= D_INT_EN;		/* enable interrupts */
229 
230 	DMA_SCSR(sc, csr);
231 
232 	sc->sc_active = 0;
233 }
234 
235 
236 #define DMAMAX(a)	(MAX_DMA_SZ - ((a) & (MAX_DMA_SZ-1)))
237 
238 /*
239  * setup a dma transfer
240  */
241 int
242 dma_setup(struct dma_softc *sc, void **addr, size_t *len, int datain,
243     size_t *dmasize)
244 {
245 	uint32_t csr;
246 
247 	DMA_FLUSH(sc, 0);
248 
249 #if 0
250 	DMA_SCSR(sc, DMA_GCSR(sc) & ~D_INT_EN);
251 #endif
252 	sc->sc_dmaaddr = addr;
253 	sc->sc_dmalen = len;
254 
255 	NCR_DMA(("%s: start %d@%p,%d\n", sc->sc_dev.dv_xname,
256 		*sc->sc_dmalen, *sc->sc_dmaaddr, datain ? 1 : 0));
257 
258 	/*
259 	 * the rules say we cannot transfer more than the limit
260 	 * of this DMA chip (64k for old and 16Mb for new),
261 	 * and we cannot cross a 16Mb boundary.
262 	 */
263 	*dmasize = sc->sc_dmasize =
264 		min(*dmasize, DMAMAX((size_t) *sc->sc_dmaaddr));
265 
266 	NCR_DMA(("dma_setup: dmasize = %d\n", sc->sc_dmasize));
267 
268 	/* Program the DMA address */
269 	if (sc->sc_dmasize) {
270 		if (bus_dmamap_load(sc->sc_dmatag, sc->sc_dmamap,
271 		    *sc->sc_dmaaddr, sc->sc_dmasize,
272 		    NULL /* kernel address */, BUS_DMA_NOWAIT))
273 			panic("%s: cannot allocate DVMA address",
274 			    sc->sc_dev.dv_xname);
275 		bus_dmamap_sync(sc->sc_dmatag, sc->sc_dmamap, 0, sc->sc_dmasize,
276 		    datain ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
277 		bus_space_write_4(sc->sc_bst, sc->sc_bsh, DMA_REG_ADDR,
278 		    sc->sc_dmamap->dm_segs[0].ds_addr);
279 	}
280 
281 	/* We never have DMAREV_ESC. */
282 
283 	/* Setup DMA control register */
284 	csr = DMA_GCSR(sc);
285 	if (datain)
286 		csr |= D_WRITE;
287 	else
288 		csr &= ~D_WRITE;
289 	csr |= D_INT_EN;
290 	DMA_SCSR(sc, csr);
291 
292 	return 0;
293 }
294 
295 /*
296  * Pseudo (chained) interrupt from the esp driver to kick the
297  * current running DMA transfer. I am relying on espintr() to
298  * pickup and clean errors for now
299  *
300  * return 1 if it was a DMA continue.
301  */
302 int
303 espdmaintr(struct dma_softc *sc)
304 {
305 	struct ncr53c9x_softc *nsc = sc->sc_client;
306 	char bits[64];
307 	int trans, resid;
308 	uint32_t csr;
309 
310 	csr = DMA_GCSR(sc);
311 
312 	NCR_DMA(("%s: intr: addr 0x%x, csr %s\n",
313 		 sc->sc_dev.dv_xname, DMADDR(sc),
314 		 bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits))));
315 
316 	if (csr & D_ERR_PEND) {
317 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
318 			bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits)));
319 		csr &= ~D_EN_DMA;	/* Stop DMA */
320 		DMA_SCSR(sc, csr);
321 		csr |= D_FLUSH;
322 		DMA_SCSR(sc, csr);
323 		return -1;
324 	}
325 
326 	/* This is an "assertion" :) */
327 	if (sc->sc_active == 0)
328 		panic("dmaintr: DMA wasn't active");
329 
330 	DMA_DRAIN(sc, 0);
331 
332 	/* DMA has stopped */
333 	csr &= ~D_EN_DMA;
334 	DMA_SCSR(sc, csr);
335 	sc->sc_active = 0;
336 
337 	if (sc->sc_dmasize == 0) {
338 		/* A "Transfer Pad" operation completed */
339 		NCR_DMA(("dmaintr: discarded %d bytes (tcl=%d, tcm=%d)\n",
340 			NCR_READ_REG(nsc, NCR_TCL) |
341 				(NCR_READ_REG(nsc, NCR_TCM) << 8),
342 			NCR_READ_REG(nsc, NCR_TCL),
343 			NCR_READ_REG(nsc, NCR_TCM)));
344 		return 0;
345 	}
346 
347 	resid = 0;
348 	/*
349 	 * If a transfer onto the SCSI bus gets interrupted by the device
350 	 * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
351 	 * as residual since the ESP counter registers get decremented as
352 	 * bytes are clocked into the FIFO.
353 	 */
354 	if (!(csr & D_WRITE) &&
355 	    (resid = (NCR_READ_REG(nsc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
356 		NCR_DMA(("dmaintr: empty esp FIFO of %d ", resid));
357 	}
358 
359 	if ((nsc->sc_espstat & NCRSTAT_TC) == 0) {
360 		/*
361 		 * `Terminal count' is off, so read the residue
362 		 * out of the ESP counter registers.
363 		 */
364 		resid += (NCR_READ_REG(nsc, NCR_TCL) |
365 			  (NCR_READ_REG(nsc, NCR_TCM) << 8) |
366 			   ((nsc->sc_cfg2 & NCRCFG2_FE)
367 				? (NCR_READ_REG(nsc, NCR_TCH) << 16)
368 				: 0));
369 
370 		if (resid == 0 && sc->sc_dmasize == 65536 &&
371 		    (nsc->sc_cfg2 & NCRCFG2_FE) == 0)
372 			/* A transfer of 64K is encoded as `TCL=TCM=0' */
373 			resid = 65536;
374 	}
375 
376 	trans = sc->sc_dmasize - resid;
377 	if (trans < 0) {			/* transferred < 0 ? */
378 #if 0
379 		/*
380 		 * This situation can happen in perfectly normal operation
381 		 * if the ESP is reselected while using DMA to select
382 		 * another target.  As such, don't print the warning.
383 		 */
384 		printf("%s: xfer (%d) > req (%d)\n",
385 		    sc->sc_dev.dv_xname, trans, sc->sc_dmasize);
386 #endif
387 		trans = sc->sc_dmasize;
388 	}
389 
390 	NCR_DMA(("dmaintr: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n",
391 		NCR_READ_REG(nsc, NCR_TCL),
392 		NCR_READ_REG(nsc, NCR_TCM),
393 		(nsc->sc_cfg2 & NCRCFG2_FE)
394 			? NCR_READ_REG(nsc, NCR_TCH) : 0,
395 		trans, resid));
396 
397 #ifdef	SUN3X_470_EVENTUALLY
398 	if (csr & D_WRITE)
399 		cache_flush(*sc->sc_dmaaddr, trans);
400 #endif
401 
402 	if (sc->sc_dmamap->dm_nsegs > 0) {
403 		bus_dmamap_sync(sc->sc_dmatag, sc->sc_dmamap, 0, sc->sc_dmasize,
404 		    (csr & D_WRITE) != 0 ?
405 		    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
406 		bus_dmamap_unload(sc->sc_dmatag, sc->sc_dmamap);
407 	}
408 
409 	*sc->sc_dmalen -= trans;
410 	*sc->sc_dmaaddr = (char *)*sc->sc_dmaaddr + trans;
411 
412 #if 0	/* this is not normal operation just yet */
413 	if (*sc->sc_dmalen == 0 ||
414 	    nsc->sc_phase != nsc->sc_prevphase)
415 		return 0;
416 
417 	/* and again */
418 	dma_start(sc, sc->sc_dmaaddr, sc->sc_dmalen, DMA_GCSR(sc) & D_WRITE);
419 	return 1;
420 #endif
421 	return 0;
422 }
423