xref: /netbsd-src/sys/arch/sun3/dev/dma.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: dma.c,v 1.16 2005/12/11 12:19:20 christos 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 1.16 2005/12/11 12:19:20 christos 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_regs = bus_mapin(ca->ca_bustype, ca->ca_paddr,
103 					  sizeof(struct dma_regs));
104 	sc->sc_rev = DMACSR(sc) & D_DEV_ID;
105 	id = (sc->sc_rev >> 28) & 0xf;
106 	printf(": rev %d\n", id);
107 
108 	/*
109 	 * Make sure the DMA chip is supported revision.
110 	 * The Sun3/80 used only the old rev zero chip,
111 	 * so the initialization has been simplified.
112 	 */
113 	switch (sc->sc_rev) {
114 	case DMAREV_0:
115 	case DMAREV_1:
116 		break;
117 	default:
118 		panic("unsupported dma rev");
119 	}
120 }
121 
122 /*
123  * This is called by espattach to get our softc.
124  */
125 struct dma_softc *
126 espdmafind(int unit)
127 {
128 	if (unit < 0 || unit >= dma_cd.cd_ndevs ||
129 		dma_cd.cd_devs[unit] == NULL)
130 		panic("no dma");
131 	return (dma_cd.cd_devs[unit]);
132 }
133 
134 #define DMAWAIT(SC, COND, MSG, DONTPANIC) do if (COND) {		\
135 	int count = 100000;						\
136 	while ((COND) && --count > 0) DELAY(5);				\
137 	if (count == 0) {						\
138 		printf("%s: line %d: CSR = 0x%x\n",			\
139 			__FILE__, __LINE__, DMACSR(SC));		\
140 		if (DONTPANIC)						\
141 			printf(MSG);					\
142 		else							\
143 			panic(MSG);					\
144 	}								\
145 } while (0)
146 
147 #define DMA_DRAIN(sc, dontpanic) do {					\
148 	/*								\
149 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
150 	 *     and "drain" bits while it is still thinking about a	\
151 	 *     request.							\
152 	 * other revs: D_R_PEND bit reads as 0				\
153 	 */								\
154 	DMAWAIT(sc, DMACSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
155 	/*								\
156 	 * Select drain bit (always rev 0,1)				\
157 	 * also clears errors and D_TC flag				\
158 	 */								\
159 	DMACSR(sc) |= D_DRAIN;						\
160 	/*								\
161 	 * Wait for draining to finish					\
162 	 */								\
163 	DMAWAIT(sc, DMACSR(sc) & D_PACKCNT, "DRAINING", dontpanic);	\
164 } while(0)
165 
166 #define DMA_FLUSH(sc, dontpanic) do {					\
167 	/*								\
168 	 * DMA rev0 & rev1: we are not allowed to touch the DMA "flush"	\
169 	 *     and "drain" bits while it is still thinking about a	\
170 	 *     request.							\
171 	 * other revs: D_R_PEND bit reads as 0				\
172 	 */								\
173 	DMAWAIT(sc, DMACSR(sc) & D_R_PEND, "R_PEND", dontpanic);	\
174 	DMACSR(sc) &= ~(D_WRITE|D_EN_DMA);				\
175 	DMACSR(sc) |= D_FLUSH;						\
176 } while(0)
177 
178 void
179 dma_reset(struct dma_softc *sc)
180 {
181 
182 	DMA_FLUSH(sc, 1);
183 	DMACSR(sc) |= D_RESET;		/* reset DMA */
184 	DELAY(200);			/* what should this be ? */
185 	/*DMAWAIT1(sc); why was this here? */
186 	DMACSR(sc) &= ~D_RESET;		/* de-assert reset line */
187 	DELAY(5);			/* allow a few ticks to settle */
188 
189 	/*
190 	 * Get transfer burst size from (?) and plug it into the
191 	 * controller registers. This is needed on the Sun4m...
192 	 * Do we need it too?  Apparently not, because the 3/80
193 	 * always has the old, REV zero DMA chip.
194 	 */
195 	DMACSR(sc) |= D_INT_EN;		/* enable interrupts */
196 
197 	sc->sc_active = 0;
198 }
199 
200 
201 #define DMAMAX(a)	(MAX_DMA_SZ - ((a) & (MAX_DMA_SZ-1)))
202 
203 /*
204  * setup a dma transfer
205  */
206 int
207 dma_setup(struct dma_softc *sc, caddr_t *addr, size_t *len, int datain,
208     size_t *dmasize)
209 {
210 	uint32_t csr;
211 
212 	DMA_FLUSH(sc, 0);
213 
214 #if 0
215 	DMACSR(sc) &= ~D_INT_EN;
216 #endif
217 	sc->sc_dmaaddr = addr;
218 	sc->sc_dmalen = len;
219 
220 	NCR_DMA(("%s: start %d@%p,%d\n", sc->sc_dev.dv_xname,
221 		*sc->sc_dmalen, *sc->sc_dmaaddr, datain ? 1 : 0));
222 
223 	/*
224 	 * the rules say we cannot transfer more than the limit
225 	 * of this DMA chip (64k for old and 16Mb for new),
226 	 * and we cannot cross a 16Mb boundary.
227 	 */
228 	*dmasize = sc->sc_dmasize =
229 		min(*dmasize, DMAMAX((size_t) *sc->sc_dmaaddr));
230 
231 	NCR_DMA(("dma_setup: dmasize = %d\n", sc->sc_dmasize));
232 
233 	/* Program the DMA address */
234 	if (sc->sc_dmasize) {
235 		/*
236 		 * Use dvma mapin routines to map the buffer into DVMA space.
237 		 */
238 		sc->sc_dvmaaddr = *sc->sc_dmaaddr;
239 		sc->sc_dvmakaddr = dvma_mapin(sc->sc_dvmaaddr,
240 					       sc->sc_dmasize, 0);
241 		if (sc->sc_dvmakaddr == NULL)
242 			panic("dma: cannot allocate DVMA address");
243 		sc->sc_dmasaddr = dvma_kvtopa(sc->sc_dvmakaddr, BUS_OBIO);
244 		DMADDR(sc) = sc->sc_dmasaddr;
245 	} else {
246 		/* XXX: What is this about? -gwr */
247 		DMADDR(sc) = (uint32_t) *sc->sc_dmaaddr;
248 	}
249 
250 	/* We never have DMAREV_ESC. */
251 
252 	/* Setup DMA control register */
253 	csr = DMACSR(sc);
254 	if (datain)
255 		csr |= D_WRITE;
256 	else
257 		csr &= ~D_WRITE;
258 	csr |= D_INT_EN;
259 	DMACSR(sc) = csr;
260 
261 	return 0;
262 }
263 
264 /*
265  * Pseudo (chained) interrupt from the esp driver to kick the
266  * current running DMA transfer. I am relying on espintr() to
267  * pickup and clean errors for now
268  *
269  * return 1 if it was a DMA continue.
270  */
271 int
272 espdmaintr(struct dma_softc *sc)
273 {
274 	struct ncr53c9x_softc *nsc = sc->sc_esp;
275 	char bits[64];
276 	int trans, resid;
277 	uint32_t csr;
278 
279 	csr = DMACSR(sc);
280 
281 	NCR_DMA(("%s: intr: addr 0x%x, csr %s\n",
282 		 sc->sc_dev.dv_xname, DMADDR(sc),
283 		 bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits))));
284 
285 	if (csr & D_ERR_PEND) {
286 		DMACSR(sc) &= ~D_EN_DMA;	/* Stop DMA */
287 		DMACSR(sc) |= D_FLUSH;
288 		printf("%s: error: csr=%s\n", sc->sc_dev.dv_xname,
289 			bitmask_snprintf(csr, DMACSRBITS, bits, sizeof(bits)));
290 		return (-1);
291 	}
292 
293 	/* This is an "assertion" :) */
294 	if (sc->sc_active == 0)
295 		panic("dmaintr: DMA wasn't active");
296 
297 	DMA_DRAIN(sc, 0);
298 
299 	/* DMA has stopped */
300 	DMACSR(sc) &= ~D_EN_DMA;
301 	sc->sc_active = 0;
302 
303 	if (sc->sc_dmasize == 0) {
304 		/* A "Transfer Pad" operation completed */
305 		NCR_DMA(("dmaintr: discarded %d bytes (tcl=%d, tcm=%d)\n",
306 			NCR_READ_REG(nsc, NCR_TCL) |
307 				(NCR_READ_REG(nsc, NCR_TCM) << 8),
308 			NCR_READ_REG(nsc, NCR_TCL),
309 			NCR_READ_REG(nsc, NCR_TCM)));
310 		return 0;
311 	}
312 
313 	resid = 0;
314 	/*
315 	 * If a transfer onto the SCSI bus gets interrupted by the device
316 	 * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
317 	 * as residual since the ESP counter registers get decremented as
318 	 * bytes are clocked into the FIFO.
319 	 */
320 	if (!(csr & D_WRITE) &&
321 	    (resid = (NCR_READ_REG(nsc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
322 		NCR_DMA(("dmaintr: empty esp FIFO of %d ", resid));
323 	}
324 
325 	if ((nsc->sc_espstat & NCRSTAT_TC) == 0) {
326 		/*
327 		 * `Terminal count' is off, so read the residue
328 		 * out of the ESP counter registers.
329 		 */
330 		resid += (NCR_READ_REG(nsc, NCR_TCL) |
331 			  (NCR_READ_REG(nsc, NCR_TCM) << 8) |
332 			   ((nsc->sc_cfg2 & NCRCFG2_FE)
333 				? (NCR_READ_REG(nsc, NCR_TCH) << 16)
334 				: 0));
335 
336 		if (resid == 0 && sc->sc_dmasize == 65536 &&
337 		    (nsc->sc_cfg2 & NCRCFG2_FE) == 0)
338 			/* A transfer of 64K is encoded as `TCL=TCM=0' */
339 			resid = 65536;
340 	}
341 
342 	trans = sc->sc_dmasize - resid;
343 	if (trans < 0) {			/* transferred < 0 ? */
344 #if 0
345 		/*
346 		 * This situation can happen in perfectly normal operation
347 		 * if the ESP is reselected while using DMA to select
348 		 * another target.  As such, don't print the warning.
349 		 */
350 		printf("%s: xfer (%d) > req (%d)\n",
351 		    sc->sc_dev.dv_xname, trans, sc->sc_dmasize);
352 #endif
353 		trans = sc->sc_dmasize;
354 	}
355 
356 	NCR_DMA(("dmaintr: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n",
357 		NCR_READ_REG(nsc, NCR_TCL),
358 		NCR_READ_REG(nsc, NCR_TCM),
359 		(nsc->sc_cfg2 & NCRCFG2_FE)
360 			? NCR_READ_REG(nsc, NCR_TCH) : 0,
361 		trans, resid));
362 
363 #ifdef	SUN3X_470_EVENTUALLY
364 	if (csr & D_WRITE)
365 		cache_flush(*sc->sc_dmaaddr, trans);
366 #endif
367 
368 	if (sc->sc_dvmakaddr)
369 		dvma_mapout(sc->sc_dvmakaddr, sc->sc_dmasize);
370 
371 	*sc->sc_dmalen -= trans;
372 	*sc->sc_dmaaddr += trans;
373 
374 #if 0	/* this is not normal operation just yet */
375 	if (*sc->sc_dmalen == 0 ||
376 	    nsc->sc_phase != nsc->sc_prevphase)
377 		return 0;
378 
379 	/* and again */
380 	dma_start(sc, sc->sc_dmaaddr, sc->sc_dmalen, DMACSR(sc) & D_WRITE);
381 	return 1;
382 #endif
383 	return 0;
384 }
385