xref: /netbsd/sys/arch/sun3/dev/dma.c (revision c4a72b64)
1 /*	$NetBSD: dma.c,v 1.13 2002/10/02 16:02:25 thorpej 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/types.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/errno.h>
38 #include <sys/device.h>
39 #include <sys/malloc.h>
40 
41 #include <machine/autoconf.h>
42 #include <machine/dvma.h>
43 
44 #include <dev/scsipi/scsi_all.h>
45 #include <dev/scsipi/scsipi_all.h>
46 #include <dev/scsipi/scsiconf.h>
47 
48 #include <dev/ic/ncr53c9xreg.h>
49 #include <dev/ic/ncr53c9xvar.h>
50 
51 #include <sun3/dev/dmareg.h>
52 #include <sun3/dev/dmavar.h>
53 
54 #define MAX_DMA_SZ	0x01000000	/* 16MB */
55 
56 static int	dmamatch  __P((struct device *, struct cfdata *, void *));
57 static void	dmaattach __P((struct device *, struct device *, void *));
58 
59 CFATTACH_DECL(dma, sizeof(struct dma_softc),
60     dmamatch, dmaattach, NULL, NULL);
61 
62 extern struct cfdriver dma_cd;
63 
64 static int
65 dmamatch(parent, cf, aux)
66 	struct device *parent;
67 	struct cfdata *cf;
68 	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(parent, self, aux)
87 	struct device *parent, *self;
88 	void *aux;
89 {
90 	struct confargs *ca = aux;
91 	struct dma_softc *sc = (void *)self;
92 	int id;
93 
94 #if 0
95 	/* indirect functions */
96 	sc->intr = espdmaintr;
97 	sc->setup = dma_setup;
98 	sc->reset = dma_reset;
99 #endif
100 
101 	/*
102 	 * Map in the registers.
103 	 */
104 	sc->sc_regs = bus_mapin(ca->ca_bustype, ca->ca_paddr,
105 					  sizeof(struct dma_regs));
106 	sc->sc_rev = DMACSR(sc) & D_DEV_ID;
107 	id = (sc->sc_rev >> 28) & 0xf;
108 	printf(": rev %d\n", id);
109 
110 	/*
111 	 * Make sure the DMA chip is supported revision.
112 	 * The Sun3/80 used only the old rev zero chip,
113 	 * so the initialization has been simplified.
114 	 */
115 	switch (sc->sc_rev) {
116 	case DMAREV_0:
117 	case DMAREV_1:
118 		break;
119 	default:
120 		panic("unsupported dma rev");
121 	}
122 }
123 
124 /*
125  * This is called by espattach to get our softc.
126  */
127 struct dma_softc *
128 espdmafind(int unit)
129 {
130 	if (unit < 0 || unit >= dma_cd.cd_ndevs ||
131 		dma_cd.cd_devs[unit] == NULL)
132 		panic("no dma");
133 	return (dma_cd.cd_devs[unit]);
134 }
135 
136 #define DMAWAIT(SC, COND, MSG, DONTPANIC) do if (COND) {		\
137 	int count = 100000;						\
138 	while ((COND) && --count > 0) DELAY(5);				\
139 	if (count == 0) {						\
140 		printf("%s: line %d: CSR = 0x%x\n",			\
141 			__FILE__, __LINE__, DMACSR(SC));		\
142 		if (DONTPANIC)						\
143 			printf(MSG);					\
144 		else							\
145 			panic(MSG);					\
146 	}								\
147 } while (0)
148 
149 #define DMA_DRAIN(sc, dontpanic) do {					\
150 	/*								\
151 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
152 	 *     and "drain" bits while it is still thinking about a	\
153 	 *     request.							\
154 	 * other revs: D_R_PEND bit reads as 0				\
155 	 */								\
156 	DMAWAIT(sc, DMACSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
157 	/*								\
158 	 * Select drain bit (always rev 0,1)				\
159 	 * also clears errors and D_TC flag				\
160 	 */								\
161 	DMACSR(sc) |= D_DRAIN;						\
162 	/*								\
163 	 * Wait for draining to finish					\
164 	 */								\
165 	DMAWAIT(sc, DMACSR(sc) & D_PACKCNT, "DRAINING", dontpanic);	\
166 } while(0)
167 
168 #define DMA_FLUSH(sc, dontpanic) do {					\
169 	/*								\
170 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
171 	 *     and "drain" bits while it is still thinking about a	\
172 	 *     request.							\
173 	 * other revs: D_R_PEND bit reads as 0				\
174 	 */								\
175 	DMAWAIT(sc, DMACSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
176 	DMACSR(sc) &= ~(D_WRITE|D_EN_DMA);				\
177 	DMACSR(sc) |= D_FLUSH;						\
178 } while(0)
179 
180 void
181 dma_reset(sc)
182 	struct dma_softc *sc;
183 {
184 
185 	DMA_FLUSH(sc, 1);
186 	DMACSR(sc) |= D_RESET;		/* reset DMA */
187 	DELAY(200);			/* what should this be ? */
188 	/*DMAWAIT1(sc); why was this here? */
189 	DMACSR(sc) &= ~D_RESET;		/* de-assert reset line */
190 	DELAY(5);			/* allow a few ticks to settle */
191 
192 	/*
193 	 * Get transfer burst size from (?) and plug it into the
194 	 * controller registers. This is needed on the Sun4m...
195 	 * Do we need it too?  Apparently not, because the 3/80
196 	 * always has the old, REV zero DMA chip.
197 	 */
198 	DMACSR(sc) |= D_INT_EN;		/* enable interrupts */
199 
200 	sc->sc_active = 0;
201 }
202 
203 
204 #define DMAMAX(a)	(MAX_DMA_SZ - ((a) & (MAX_DMA_SZ-1)))
205 
206 /*
207  * setup a dma transfer
208  */
209 int
210 dma_setup(sc, addr, len, datain, dmasize)
211 	struct dma_softc *sc;
212 	caddr_t *addr;
213 	size_t *len;
214 	int datain;
215 	size_t *dmasize;	/* IN-OUT */
216 {
217 	u_int32_t csr;
218 
219 	DMA_FLUSH(sc, 0);
220 
221 #if 0
222 	DMACSR(sc) &= ~D_INT_EN;
223 #endif
224 	sc->sc_dmaaddr = addr;
225 	sc->sc_dmalen = len;
226 
227 	NCR_DMA(("%s: start %d@%p,%d\n", sc->sc_dev.dv_xname,
228 		*sc->sc_dmalen, *sc->sc_dmaaddr, datain ? 1 : 0));
229 
230 	/*
231 	 * the rules say we cannot transfer more than the limit
232 	 * of this DMA chip (64k for old and 16Mb for new),
233 	 * and we cannot cross a 16Mb boundary.
234 	 */
235 	*dmasize = sc->sc_dmasize =
236 		min(*dmasize, DMAMAX((size_t) *sc->sc_dmaaddr));
237 
238 	NCR_DMA(("dma_setup: dmasize = %d\n", sc->sc_dmasize));
239 
240 	/* Program the DMA address */
241 	if (sc->sc_dmasize) {
242 		/*
243 		 * Use dvma mapin routines to map the buffer into DVMA space.
244 		 */
245 		sc->sc_dvmaaddr = *sc->sc_dmaaddr;
246 		sc->sc_dvmakaddr = dvma_mapin(sc->sc_dvmaaddr,
247 					       sc->sc_dmasize, 0);
248 		if (sc->sc_dvmakaddr == NULL)
249 			panic("dma: cannot allocate DVMA address");
250 		sc->sc_dmasaddr = dvma_kvtopa(sc->sc_dvmakaddr, BUS_OBIO);
251 		DMADDR(sc) = sc->sc_dmasaddr;
252 	} else {
253 		/* XXX: What is this about? -gwr */
254 		DMADDR(sc) = (u_int32_t) *sc->sc_dmaaddr;
255 	}
256 
257 	/* We never have DMAREV_ESC. */
258 
259 	/* Setup DMA control register */
260 	csr = DMACSR(sc);
261 	if (datain)
262 		csr |= D_WRITE;
263 	else
264 		csr &= ~D_WRITE;
265 	csr |= D_INT_EN;
266 	DMACSR(sc) = csr;
267 
268 	return 0;
269 }
270 
271 /*
272  * Pseudo (chained) interrupt from the esp driver to kick the
273  * current running DMA transfer. I am relying on espintr() to
274  * pickup and clean errors for now
275  *
276  * return 1 if it was a DMA continue.
277  */
278 int
279 espdmaintr(sc)
280 	struct dma_softc *sc;
281 {
282 	struct ncr53c9x_softc *nsc = sc->sc_esp;
283 	char bits[64];
284 	int trans, resid;
285 	u_int32_t csr;
286 
287 	csr = DMACSR(sc);
288 
289 	NCR_DMA(("%s: intr: addr 0x%x, csr %s\n",
290 		 sc->sc_dev.dv_xname, DMADDR(sc),
291 		 bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits))));
292 
293 	if (csr & D_ERR_PEND) {
294 		DMACSR(sc) &= ~D_EN_DMA;	/* Stop DMA */
295 		DMACSR(sc) |= D_FLUSH;
296 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
297 			bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits)));
298 		return (-1);
299 	}
300 
301 	/* This is an "assertion" :) */
302 	if (sc->sc_active == 0)
303 		panic("dmaintr: DMA wasn't active");
304 
305 	DMA_DRAIN(sc, 0);
306 
307 	/* DMA has stopped */
308 	DMACSR(sc) &= ~D_EN_DMA;
309 	sc->sc_active = 0;
310 
311 	if (sc->sc_dmasize == 0) {
312 		/* A "Transfer Pad" operation completed */
313 		NCR_DMA(("dmaintr: discarded %d bytes (tcl=%d, tcm=%d)\n",
314 			NCR_READ_REG(nsc, NCR_TCL) |
315 				(NCR_READ_REG(nsc, NCR_TCM) << 8),
316 			NCR_READ_REG(nsc, NCR_TCL),
317 			NCR_READ_REG(nsc, NCR_TCM)));
318 		return 0;
319 	}
320 
321 	resid = 0;
322 	/*
323 	 * If a transfer onto the SCSI bus gets interrupted by the device
324 	 * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
325 	 * as residual since the ESP counter registers get decremented as
326 	 * bytes are clocked into the FIFO.
327 	 */
328 	if (!(csr & D_WRITE) &&
329 	    (resid = (NCR_READ_REG(nsc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
330 		NCR_DMA(("dmaintr: empty esp FIFO of %d ", resid));
331 	}
332 
333 	if ((nsc->sc_espstat & NCRSTAT_TC) == 0) {
334 		/*
335 		 * `Terminal count' is off, so read the residue
336 		 * out of the ESP counter registers.
337 		 */
338 		resid += (NCR_READ_REG(nsc, NCR_TCL) |
339 			  (NCR_READ_REG(nsc, NCR_TCM) << 8) |
340 			   ((nsc->sc_cfg2 & NCRCFG2_FE)
341 				? (NCR_READ_REG(nsc, NCR_TCH) << 16)
342 				: 0));
343 
344 		if (resid == 0 && sc->sc_dmasize == 65536 &&
345 		    (nsc->sc_cfg2 & NCRCFG2_FE) == 0)
346 			/* A transfer of 64K is encoded as `TCL=TCM=0' */
347 			resid = 65536;
348 	}
349 
350 	trans = sc->sc_dmasize - resid;
351 	if (trans < 0) {			/* transferred < 0 ? */
352 #if 0
353 		/*
354 		 * This situation can happen in perfectly normal operation
355 		 * if the ESP is reselected while using DMA to select
356 		 * another target.  As such, don't print the warning.
357 		 */
358 		printf("%s: xfer (%d) > req (%d)\n",
359 		    sc->sc_dev.dv_xname, trans, sc->sc_dmasize);
360 #endif
361 		trans = sc->sc_dmasize;
362 	}
363 
364 	NCR_DMA(("dmaintr: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n",
365 		NCR_READ_REG(nsc, NCR_TCL),
366 		NCR_READ_REG(nsc, NCR_TCM),
367 		(nsc->sc_cfg2 & NCRCFG2_FE)
368 			? NCR_READ_REG(nsc, NCR_TCH) : 0,
369 		trans, resid));
370 
371 #ifdef	SUN3X_470_EVENTUALLY
372 	if (csr & D_WRITE)
373 		cache_flush(*sc->sc_dmaaddr, trans);
374 #endif
375 
376 	if (sc->sc_dvmakaddr)
377 		dvma_mapout(sc->sc_dvmakaddr, sc->sc_dmasize);
378 
379 	*sc->sc_dmalen -= trans;
380 	*sc->sc_dmaaddr += trans;
381 
382 #if 0	/* this is not normal operation just yet */
383 	if (*sc->sc_dmalen == 0 ||
384 	    nsc->sc_phase != nsc->sc_prevphase)
385 		return 0;
386 
387 	/* and again */
388 	dma_start(sc, sc->sc_dmaaddr, sc->sc_dmalen, DMACSR(sc) & D_WRITE);
389 	return 1;
390 #endif
391 	return 0;
392 }
393