xref: /freebsd/sys/powerpc/powermac/ata_dbdma.c (revision c6ec7d31830ab1c80edae95ad5e4b9dba10c47ac)
1 /*-
2  * Copyright 2008 by Nathan Whitehorn. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 /*
31  * Common routines for the DMA engine on both the Apple Kauai and MacIO
32  * ATA controllers.
33  */
34 
35 #include "opt_ata.h"
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/module.h>
40 #include <sys/bus.h>
41 #include <sys/malloc.h>
42 #include <sys/sema.h>
43 #include <sys/taskqueue.h>
44 #include <vm/uma.h>
45 #include <machine/stdarg.h>
46 #include <machine/resource.h>
47 #include <machine/bus.h>
48 #include <sys/rman.h>
49 #include <sys/ata.h>
50 #include <dev/ata/ata-all.h>
51 #include <dev/ata/ata-pci.h>
52 #include <ata_if.h>
53 
54 #include "ata_dbdma.h"
55 
56 struct ata_dbdma_dmaload_args {
57 	struct ata_dbdma_channel *sc;
58 
59 	int write;
60 	int nsegs;
61 };
62 
63 static void
64 ata_dbdma_setprd(void *xarg, bus_dma_segment_t *segs, int nsegs, int error)
65 {
66 	struct ata_dbdma_dmaload_args *arg = xarg;
67 	struct ata_dbdma_channel *sc = arg->sc;
68 	int branch_type, command;
69 	int prev_stop;
70 	int i;
71 
72 	mtx_lock(&sc->dbdma_mtx);
73 
74 	prev_stop = sc->next_dma_slot-1;
75 	if (prev_stop < 0)
76 		prev_stop = 0xff;
77 
78 	for (i = 0; i < nsegs; i++) {
79 		/* Loop back to the beginning if this is our last slot */
80 		if (sc->next_dma_slot == 0xff)
81 			branch_type = DBDMA_ALWAYS;
82 		else
83 			branch_type = DBDMA_NEVER;
84 
85 		if (arg->write) {
86 			command = (i + 1 < nsegs) ? DBDMA_OUTPUT_MORE :
87 			    DBDMA_OUTPUT_LAST;
88 		} else {
89 			command = (i + 1 < nsegs) ? DBDMA_INPUT_MORE :
90 			    DBDMA_INPUT_LAST;
91 		}
92 
93 		dbdma_insert_command(sc->dbdma, sc->next_dma_slot++,
94 		    command, 0, segs[i].ds_addr, segs[i].ds_len,
95 		    DBDMA_NEVER, branch_type, DBDMA_NEVER, 0);
96 
97 		if (branch_type == DBDMA_ALWAYS)
98 			sc->next_dma_slot = 0;
99 	}
100 
101 	/* We have a corner case where the STOP command is the last slot,
102 	 * but you can't branch in STOP commands. So add a NOP branch here
103 	 * and the STOP in slot 0. */
104 
105 	if (sc->next_dma_slot == 0xff) {
106 		dbdma_insert_branch(sc->dbdma, sc->next_dma_slot, 0);
107 		sc->next_dma_slot = 0;
108 	}
109 
110 #if 0
111 	dbdma_insert_command(sc->dbdma, sc->next_dma_slot++,
112 	    DBDMA_NOP, 0, 0, 0, DBDMA_ALWAYS, DBDMA_NEVER, DBDMA_NEVER, 0);
113 #endif
114 	dbdma_insert_stop(sc->dbdma, sc->next_dma_slot++);
115 	dbdma_insert_nop(sc->dbdma, prev_stop);
116 
117 	dbdma_sync_commands(sc->dbdma, BUS_DMASYNC_PREWRITE);
118 
119 	mtx_unlock(&sc->dbdma_mtx);
120 
121 	arg->nsegs = nsegs;
122 }
123 
124 static int
125 ata_dbdma_status(device_t dev)
126 {
127 	struct ata_dbdma_channel *sc = device_get_softc(dev);
128 	struct ata_channel *ch = device_get_softc(dev);
129 
130 	if (sc->sc_ch.dma.flags & ATA_DMA_ACTIVE) {
131 		return (!(dbdma_get_chan_status(sc->dbdma) &
132 		    DBDMA_STATUS_ACTIVE));
133 	}
134 
135 	if (ATA_IDX_INB(ch, ATA_ALTSTAT) & ATA_S_BUSY) {
136 		DELAY(100);
137 		if (ATA_IDX_INB(ch, ATA_ALTSTAT) & ATA_S_BUSY)
138 			return 0;
139 	}
140 	return 1;
141 }
142 
143 static int
144 ata_dbdma_start(struct ata_request *request)
145 {
146 	struct ata_dbdma_channel *sc = device_get_softc(request->parent);
147 
148 	sc->sc_ch.dma.flags |= ATA_DMA_ACTIVE;
149 	dbdma_wake(sc->dbdma);
150 	return 0;
151 }
152 
153 static void
154 ata_dbdma_reset(device_t dev)
155 {
156 	struct ata_dbdma_channel *sc = device_get_softc(dev);
157 
158 	mtx_lock(&sc->dbdma_mtx);
159 
160 	dbdma_stop(sc->dbdma);
161 	dbdma_insert_stop(sc->dbdma, 0);
162 	sc->next_dma_slot=1;
163 	dbdma_set_current_cmd(sc->dbdma, 0);
164 
165 	sc->sc_ch.dma.flags &= ~ATA_DMA_ACTIVE;
166 
167 	mtx_unlock(&sc->dbdma_mtx);
168 }
169 
170 static int
171 ata_dbdma_stop(struct ata_request *request)
172 {
173 	struct ata_dbdma_channel *sc = device_get_softc(request->parent);
174 
175 	uint16_t status;
176 
177 	status = dbdma_get_chan_status(sc->dbdma);
178 
179 	dbdma_pause(sc->dbdma);
180 	sc->sc_ch.dma.flags &= ~ATA_DMA_ACTIVE;
181 
182 	if (status & DBDMA_STATUS_DEAD) {
183 		device_printf(request->parent,"DBDMA dead, resetting "
184 		    "channel...\n");
185 		ata_dbdma_reset(request->parent);
186 		return ATA_S_ERROR;
187 	}
188 
189 	if (!(status & DBDMA_STATUS_RUN)) {
190 		device_printf(request->parent,"DBDMA confused, stop called "
191 		    "when channel is not running!\n");
192 		return ATA_S_ERROR;
193 	}
194 
195 	if (status & DBDMA_STATUS_ACTIVE) {
196 		device_printf(request->parent,"DBDMA channel stopped "
197 		    "prematurely\n");
198 		return ATA_S_ERROR;
199 	}
200 	return 0;
201 }
202 
203 static int
204 ata_dbdma_load(struct ata_request *request, void *addr, int *entries)
205 {
206 	struct ata_channel *ch = device_get_softc(request->parent);
207 	struct ata_dbdma_dmaload_args args;
208 
209 	int error;
210 
211 	args.sc = device_get_softc(request->parent);
212 	args.write = !(request->flags & ATA_R_READ);
213 
214 	if (!request->bytecount) {
215 		device_printf(request->dev,
216 		    "FAILURE - zero length DMA transfer attempted\n");
217 		return EIO;
218 	}
219 	if (((uintptr_t)(request->data) & (ch->dma.alignment - 1)) ||
220 	    (request->bytecount & (ch->dma.alignment - 1))) {
221 		device_printf(request->dev,
222 		    "FAILURE - non aligned DMA transfer attempted\n");
223 		return EIO;
224 	}
225 	if (request->bytecount > ch->dma.max_iosize) {
226 		device_printf(request->dev,
227 		    "FAILURE - oversized DMA transfer attempt %d > %d\n",
228 		    request->bytecount, ch->dma.max_iosize);
229 		return EIO;
230 	}
231 
232 	request->dma = &ch->dma.slot[0];
233 
234 	if ((error = bus_dmamap_load(request->dma->data_tag,
235 	    request->dma->data_map, request->data, request->bytecount,
236 	    &ata_dbdma_setprd, &args, BUS_DMA_NOWAIT))) {
237 		device_printf(request->dev, "FAILURE - load data\n");
238 		goto error;
239 	}
240 
241 	if (entries)
242 		*entries = args.nsegs;
243 
244 	bus_dmamap_sync(request->dma->sg_tag, request->dma->sg_map,
245 	    BUS_DMASYNC_PREWRITE);
246 	bus_dmamap_sync(request->dma->data_tag, request->dma->data_map,
247 	    (request->flags & ATA_R_READ) ?
248 	    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
249 
250 	return 0;
251 
252 error:
253 	ch->dma.unload(request);
254 	return EIO;
255 }
256 
257 void
258 ata_dbdma_dmainit(device_t dev)
259 {
260 	struct ata_dbdma_channel *sc = device_get_softc(dev);
261 	int error;
262 
263 	error = dbdma_allocate_channel(sc->dbdma_regs, sc->dbdma_offset,
264 	    bus_get_dma_tag(dev), 256, &sc->dbdma);
265 
266 	dbdma_set_wait_selector(sc->dbdma,1 << 7, 1 << 7);
267 
268 	dbdma_insert_stop(sc->dbdma,0);
269 	sc->next_dma_slot=1;
270 
271 	sc->sc_ch.dma.start = ata_dbdma_start;
272 	sc->sc_ch.dma.stop = ata_dbdma_stop;
273 	sc->sc_ch.dma.load = ata_dbdma_load;
274 	sc->sc_ch.dma.reset = ata_dbdma_reset;
275 
276 	/*
277 	 * DBDMA's field for transfer size is 16 bits. This will overflow
278 	 * if we try to do a 64K transfer, so stop short of 64K.
279 	 */
280 	sc->sc_ch.dma.segsize = 126 * DEV_BSIZE;
281 	ata_dmainit(dev);
282 
283 	sc->sc_ch.hw.status = ata_dbdma_status;
284 
285 	mtx_init(&sc->dbdma_mtx, "ATA DBDMA", NULL, MTX_DEF);
286 }
287