xref: /netbsd-src/sys/arch/sun3/dev/dma.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: dma.c,v 1.14 2003/07/15 03:36:14 lukem 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 1.14 2003/07/15 03:36:14 lukem 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  __P((struct device *, struct cfdata *, void *));
60 static void	dmaattach __P((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(parent, cf, aux)
69 	struct device *parent;
70 	struct cfdata *cf;
71 	void *aux;
72 {
73 	struct confargs *ca = aux;
74 
75 	/*
76 	 * Check for the DMA registers.
77 	 */
78 	if (bus_peek(ca->ca_bustype, ca->ca_paddr, 4) == -1)
79 		return (0);
80 
81 	/* If default ipl, fill it in. */
82 	if (ca->ca_intpri == -1)
83 		ca->ca_intpri = 2;
84 
85 	return (1);
86 }
87 
88 static void
89 dmaattach(parent, self, aux)
90 	struct device *parent, *self;
91 	void *aux;
92 {
93 	struct confargs *ca = aux;
94 	struct dma_softc *sc = (void *)self;
95 	int id;
96 
97 #if 0
98 	/* indirect functions */
99 	sc->intr = espdmaintr;
100 	sc->setup = dma_setup;
101 	sc->reset = dma_reset;
102 #endif
103 
104 	/*
105 	 * Map in the registers.
106 	 */
107 	sc->sc_regs = bus_mapin(ca->ca_bustype, ca->ca_paddr,
108 					  sizeof(struct dma_regs));
109 	sc->sc_rev = DMACSR(sc) & D_DEV_ID;
110 	id = (sc->sc_rev >> 28) & 0xf;
111 	printf(": rev %d\n", id);
112 
113 	/*
114 	 * Make sure the DMA chip is supported revision.
115 	 * The Sun3/80 used only the old rev zero chip,
116 	 * so the initialization has been simplified.
117 	 */
118 	switch (sc->sc_rev) {
119 	case DMAREV_0:
120 	case DMAREV_1:
121 		break;
122 	default:
123 		panic("unsupported dma rev");
124 	}
125 }
126 
127 /*
128  * This is called by espattach to get our softc.
129  */
130 struct dma_softc *
131 espdmafind(int unit)
132 {
133 	if (unit < 0 || unit >= dma_cd.cd_ndevs ||
134 		dma_cd.cd_devs[unit] == NULL)
135 		panic("no dma");
136 	return (dma_cd.cd_devs[unit]);
137 }
138 
139 #define DMAWAIT(SC, COND, MSG, DONTPANIC) do if (COND) {		\
140 	int count = 100000;						\
141 	while ((COND) && --count > 0) DELAY(5);				\
142 	if (count == 0) {						\
143 		printf("%s: line %d: CSR = 0x%x\n",			\
144 			__FILE__, __LINE__, DMACSR(SC));		\
145 		if (DONTPANIC)						\
146 			printf(MSG);					\
147 		else							\
148 			panic(MSG);					\
149 	}								\
150 } while (0)
151 
152 #define DMA_DRAIN(sc, dontpanic) do {					\
153 	/*								\
154 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
155 	 *     and "drain" bits while it is still thinking about a	\
156 	 *     request.							\
157 	 * other revs: D_R_PEND bit reads as 0				\
158 	 */								\
159 	DMAWAIT(sc, DMACSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
160 	/*								\
161 	 * Select drain bit (always rev 0,1)				\
162 	 * also clears errors and D_TC flag				\
163 	 */								\
164 	DMACSR(sc) |= D_DRAIN;						\
165 	/*								\
166 	 * Wait for draining to finish					\
167 	 */								\
168 	DMAWAIT(sc, DMACSR(sc) & D_PACKCNT, "DRAINING", dontpanic);	\
169 } while(0)
170 
171 #define DMA_FLUSH(sc, dontpanic) do {					\
172 	/*								\
173 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
174 	 *     and "drain" bits while it is still thinking about a	\
175 	 *     request.							\
176 	 * other revs: D_R_PEND bit reads as 0				\
177 	 */								\
178 	DMAWAIT(sc, DMACSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
179 	DMACSR(sc) &= ~(D_WRITE|D_EN_DMA);				\
180 	DMACSR(sc) |= D_FLUSH;						\
181 } while(0)
182 
183 void
184 dma_reset(sc)
185 	struct dma_softc *sc;
186 {
187 
188 	DMA_FLUSH(sc, 1);
189 	DMACSR(sc) |= D_RESET;		/* reset DMA */
190 	DELAY(200);			/* what should this be ? */
191 	/*DMAWAIT1(sc); why was this here? */
192 	DMACSR(sc) &= ~D_RESET;		/* de-assert reset line */
193 	DELAY(5);			/* allow a few ticks to settle */
194 
195 	/*
196 	 * Get transfer burst size from (?) and plug it into the
197 	 * controller registers. This is needed on the Sun4m...
198 	 * Do we need it too?  Apparently not, because the 3/80
199 	 * always has the old, REV zero DMA chip.
200 	 */
201 	DMACSR(sc) |= D_INT_EN;		/* enable interrupts */
202 
203 	sc->sc_active = 0;
204 }
205 
206 
207 #define DMAMAX(a)	(MAX_DMA_SZ - ((a) & (MAX_DMA_SZ-1)))
208 
209 /*
210  * setup a dma transfer
211  */
212 int
213 dma_setup(sc, addr, len, datain, dmasize)
214 	struct dma_softc *sc;
215 	caddr_t *addr;
216 	size_t *len;
217 	int datain;
218 	size_t *dmasize;	/* IN-OUT */
219 {
220 	u_int32_t csr;
221 
222 	DMA_FLUSH(sc, 0);
223 
224 #if 0
225 	DMACSR(sc) &= ~D_INT_EN;
226 #endif
227 	sc->sc_dmaaddr = addr;
228 	sc->sc_dmalen = len;
229 
230 	NCR_DMA(("%s: start %d@%p,%d\n", sc->sc_dev.dv_xname,
231 		*sc->sc_dmalen, *sc->sc_dmaaddr, datain ? 1 : 0));
232 
233 	/*
234 	 * the rules say we cannot transfer more than the limit
235 	 * of this DMA chip (64k for old and 16Mb for new),
236 	 * and we cannot cross a 16Mb boundary.
237 	 */
238 	*dmasize = sc->sc_dmasize =
239 		min(*dmasize, DMAMAX((size_t) *sc->sc_dmaaddr));
240 
241 	NCR_DMA(("dma_setup: dmasize = %d\n", sc->sc_dmasize));
242 
243 	/* Program the DMA address */
244 	if (sc->sc_dmasize) {
245 		/*
246 		 * Use dvma mapin routines to map the buffer into DVMA space.
247 		 */
248 		sc->sc_dvmaaddr = *sc->sc_dmaaddr;
249 		sc->sc_dvmakaddr = dvma_mapin(sc->sc_dvmaaddr,
250 					       sc->sc_dmasize, 0);
251 		if (sc->sc_dvmakaddr == NULL)
252 			panic("dma: cannot allocate DVMA address");
253 		sc->sc_dmasaddr = dvma_kvtopa(sc->sc_dvmakaddr, BUS_OBIO);
254 		DMADDR(sc) = sc->sc_dmasaddr;
255 	} else {
256 		/* XXX: What is this about? -gwr */
257 		DMADDR(sc) = (u_int32_t) *sc->sc_dmaaddr;
258 	}
259 
260 	/* We never have DMAREV_ESC. */
261 
262 	/* Setup DMA control register */
263 	csr = DMACSR(sc);
264 	if (datain)
265 		csr |= D_WRITE;
266 	else
267 		csr &= ~D_WRITE;
268 	csr |= D_INT_EN;
269 	DMACSR(sc) = csr;
270 
271 	return 0;
272 }
273 
274 /*
275  * Pseudo (chained) interrupt from the esp driver to kick the
276  * current running DMA transfer. I am relying on espintr() to
277  * pickup and clean errors for now
278  *
279  * return 1 if it was a DMA continue.
280  */
281 int
282 espdmaintr(sc)
283 	struct dma_softc *sc;
284 {
285 	struct ncr53c9x_softc *nsc = sc->sc_esp;
286 	char bits[64];
287 	int trans, resid;
288 	u_int32_t csr;
289 
290 	csr = DMACSR(sc);
291 
292 	NCR_DMA(("%s: intr: addr 0x%x, csr %s\n",
293 		 sc->sc_dev.dv_xname, DMADDR(sc),
294 		 bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits))));
295 
296 	if (csr & D_ERR_PEND) {
297 		DMACSR(sc) &= ~D_EN_DMA;	/* Stop DMA */
298 		DMACSR(sc) |= D_FLUSH;
299 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
300 			bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits)));
301 		return (-1);
302 	}
303 
304 	/* This is an "assertion" :) */
305 	if (sc->sc_active == 0)
306 		panic("dmaintr: DMA wasn't active");
307 
308 	DMA_DRAIN(sc, 0);
309 
310 	/* DMA has stopped */
311 	DMACSR(sc) &= ~D_EN_DMA;
312 	sc->sc_active = 0;
313 
314 	if (sc->sc_dmasize == 0) {
315 		/* A "Transfer Pad" operation completed */
316 		NCR_DMA(("dmaintr: discarded %d bytes (tcl=%d, tcm=%d)\n",
317 			NCR_READ_REG(nsc, NCR_TCL) |
318 				(NCR_READ_REG(nsc, NCR_TCM) << 8),
319 			NCR_READ_REG(nsc, NCR_TCL),
320 			NCR_READ_REG(nsc, NCR_TCM)));
321 		return 0;
322 	}
323 
324 	resid = 0;
325 	/*
326 	 * If a transfer onto the SCSI bus gets interrupted by the device
327 	 * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
328 	 * as residual since the ESP counter registers get decremented as
329 	 * bytes are clocked into the FIFO.
330 	 */
331 	if (!(csr & D_WRITE) &&
332 	    (resid = (NCR_READ_REG(nsc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
333 		NCR_DMA(("dmaintr: empty esp FIFO of %d ", resid));
334 	}
335 
336 	if ((nsc->sc_espstat & NCRSTAT_TC) == 0) {
337 		/*
338 		 * `Terminal count' is off, so read the residue
339 		 * out of the ESP counter registers.
340 		 */
341 		resid += (NCR_READ_REG(nsc, NCR_TCL) |
342 			  (NCR_READ_REG(nsc, NCR_TCM) << 8) |
343 			   ((nsc->sc_cfg2 & NCRCFG2_FE)
344 				? (NCR_READ_REG(nsc, NCR_TCH) << 16)
345 				: 0));
346 
347 		if (resid == 0 && sc->sc_dmasize == 65536 &&
348 		    (nsc->sc_cfg2 & NCRCFG2_FE) == 0)
349 			/* A transfer of 64K is encoded as `TCL=TCM=0' */
350 			resid = 65536;
351 	}
352 
353 	trans = sc->sc_dmasize - resid;
354 	if (trans < 0) {			/* transferred < 0 ? */
355 #if 0
356 		/*
357 		 * This situation can happen in perfectly normal operation
358 		 * if the ESP is reselected while using DMA to select
359 		 * another target.  As such, don't print the warning.
360 		 */
361 		printf("%s: xfer (%d) > req (%d)\n",
362 		    sc->sc_dev.dv_xname, trans, sc->sc_dmasize);
363 #endif
364 		trans = sc->sc_dmasize;
365 	}
366 
367 	NCR_DMA(("dmaintr: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n",
368 		NCR_READ_REG(nsc, NCR_TCL),
369 		NCR_READ_REG(nsc, NCR_TCM),
370 		(nsc->sc_cfg2 & NCRCFG2_FE)
371 			? NCR_READ_REG(nsc, NCR_TCH) : 0,
372 		trans, resid));
373 
374 #ifdef	SUN3X_470_EVENTUALLY
375 	if (csr & D_WRITE)
376 		cache_flush(*sc->sc_dmaaddr, trans);
377 #endif
378 
379 	if (sc->sc_dvmakaddr)
380 		dvma_mapout(sc->sc_dvmakaddr, sc->sc_dmasize);
381 
382 	*sc->sc_dmalen -= trans;
383 	*sc->sc_dmaaddr += trans;
384 
385 #if 0	/* this is not normal operation just yet */
386 	if (*sc->sc_dmalen == 0 ||
387 	    nsc->sc_phase != nsc->sc_prevphase)
388 		return 0;
389 
390 	/* and again */
391 	dma_start(sc, sc->sc_dmaaddr, sc->sc_dmalen, DMACSR(sc) & D_WRITE);
392 	return 1;
393 #endif
394 	return 0;
395 }
396