xref: /freebsd/sys/powerpc/powermac/ata_dbdma.c (revision d4eeb02986980bf33dd56c41ceb9fc5f180c0d47)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright 2008 by Nathan Whitehorn. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
22  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("* $FreeBSD$");
32 
33 /*
34  * Common routines for the DMA engine on both the Apple Kauai and MacIO
35  * ATA controllers.
36  */
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/kernel.h>
41 #include <sys/module.h>
42 #include <sys/bus.h>
43 #include <sys/malloc.h>
44 #include <sys/sema.h>
45 #include <sys/taskqueue.h>
46 #include <vm/uma.h>
47 #include <machine/stdarg.h>
48 #include <machine/resource.h>
49 #include <machine/bus.h>
50 #include <sys/rman.h>
51 #include <sys/ata.h>
52 #include <dev/ata/ata-all.h>
53 #include <dev/ata/ata-pci.h>
54 #include <ata_if.h>
55 
56 #include "ata_dbdma.h"
57 
58 struct ata_dbdma_dmaload_args {
59 	struct ata_dbdma_channel *sc;
60 
61 	int write;
62 	int nsegs;
63 };
64 
65 static void
66 ata_dbdma_setprd(void *xarg, bus_dma_segment_t *segs, int nsegs, int error)
67 {
68 	struct ata_dbdma_dmaload_args *arg = xarg;
69 	struct ata_dbdma_channel *sc = arg->sc;
70 	int branch_type, command;
71 	int prev_stop;
72 	int i;
73 
74 	mtx_lock(&sc->dbdma_mtx);
75 
76 	prev_stop = sc->next_dma_slot-1;
77 	if (prev_stop < 0)
78 		prev_stop = 0xff;
79 
80 	for (i = 0; i < nsegs; i++) {
81 		/* Loop back to the beginning if this is our last slot */
82 		if (sc->next_dma_slot == 0xff)
83 			branch_type = DBDMA_ALWAYS;
84 		else
85 			branch_type = DBDMA_NEVER;
86 
87 		if (arg->write) {
88 			command = (i + 1 < nsegs) ? DBDMA_OUTPUT_MORE :
89 			    DBDMA_OUTPUT_LAST;
90 		} else {
91 			command = (i + 1 < nsegs) ? DBDMA_INPUT_MORE :
92 			    DBDMA_INPUT_LAST;
93 		}
94 
95 		dbdma_insert_command(sc->dbdma, sc->next_dma_slot++,
96 		    command, 0, segs[i].ds_addr, segs[i].ds_len,
97 		    DBDMA_NEVER, branch_type, DBDMA_NEVER, 0);
98 
99 		if (branch_type == DBDMA_ALWAYS)
100 			sc->next_dma_slot = 0;
101 	}
102 
103 	/* We have a corner case where the STOP command is the last slot,
104 	 * but you can't branch in STOP commands. So add a NOP branch here
105 	 * and the STOP in slot 0. */
106 
107 	if (sc->next_dma_slot == 0xff) {
108 		dbdma_insert_branch(sc->dbdma, sc->next_dma_slot, 0);
109 		sc->next_dma_slot = 0;
110 	}
111 
112 #if 0
113 	dbdma_insert_command(sc->dbdma, sc->next_dma_slot++,
114 	    DBDMA_NOP, 0, 0, 0, DBDMA_ALWAYS, DBDMA_NEVER, DBDMA_NEVER, 0);
115 #endif
116 	dbdma_insert_stop(sc->dbdma, sc->next_dma_slot++);
117 	dbdma_insert_nop(sc->dbdma, prev_stop);
118 
119 	dbdma_sync_commands(sc->dbdma, BUS_DMASYNC_PREWRITE);
120 
121 	mtx_unlock(&sc->dbdma_mtx);
122 
123 	arg->nsegs = nsegs;
124 }
125 
126 static int
127 ata_dbdma_status(device_t dev)
128 {
129 	struct ata_dbdma_channel *sc = device_get_softc(dev);
130 	struct ata_channel *ch = device_get_softc(dev);
131 
132 	if (sc->sc_ch.dma.flags & ATA_DMA_ACTIVE) {
133 		return (!(dbdma_get_chan_status(sc->dbdma) &
134 		    DBDMA_STATUS_ACTIVE));
135 	}
136 
137 	if (ATA_IDX_INB(ch, ATA_ALTSTAT) & ATA_S_BUSY) {
138 		DELAY(100);
139 		if (ATA_IDX_INB(ch, ATA_ALTSTAT) & ATA_S_BUSY)
140 			return 0;
141 	}
142 	return 1;
143 }
144 
145 static int
146 ata_dbdma_start(struct ata_request *request)
147 {
148 	struct ata_dbdma_channel *sc = device_get_softc(request->parent);
149 
150 	sc->sc_ch.dma.flags |= ATA_DMA_ACTIVE;
151 	dbdma_wake(sc->dbdma);
152 	return 0;
153 }
154 
155 static void
156 ata_dbdma_reset(device_t dev)
157 {
158 	struct ata_dbdma_channel *sc = device_get_softc(dev);
159 
160 	mtx_lock(&sc->dbdma_mtx);
161 
162 	dbdma_stop(sc->dbdma);
163 	dbdma_insert_stop(sc->dbdma, 0);
164 	sc->next_dma_slot=1;
165 	dbdma_set_current_cmd(sc->dbdma, 0);
166 
167 	sc->sc_ch.dma.flags &= ~ATA_DMA_ACTIVE;
168 
169 	mtx_unlock(&sc->dbdma_mtx);
170 }
171 
172 static int
173 ata_dbdma_stop(struct ata_request *request)
174 {
175 	struct ata_dbdma_channel *sc = device_get_softc(request->parent);
176 
177 	uint16_t status;
178 
179 	status = dbdma_get_chan_status(sc->dbdma);
180 
181 	dbdma_pause(sc->dbdma);
182 	sc->sc_ch.dma.flags &= ~ATA_DMA_ACTIVE;
183 
184 	if (status & DBDMA_STATUS_DEAD) {
185 		device_printf(request->parent,"DBDMA dead, resetting "
186 		    "channel...\n");
187 		ata_dbdma_reset(request->parent);
188 		return ATA_S_ERROR;
189 	}
190 
191 	if (!(status & DBDMA_STATUS_RUN)) {
192 		device_printf(request->parent,"DBDMA confused, stop called "
193 		    "when channel is not running!\n");
194 		return ATA_S_ERROR;
195 	}
196 
197 	if (status & DBDMA_STATUS_ACTIVE) {
198 		device_printf(request->parent,"DBDMA channel stopped "
199 		    "prematurely\n");
200 		return ATA_S_ERROR;
201 	}
202 	return 0;
203 }
204 
205 static int
206 ata_dbdma_load(struct ata_request *request, void *addr, int *entries)
207 {
208 	struct ata_channel *ch = device_get_softc(request->parent);
209 	struct ata_dbdma_dmaload_args args;
210 
211 	int error;
212 
213 	args.sc = device_get_softc(request->parent);
214 	args.write = !(request->flags & ATA_R_READ);
215 
216 	if (!request->bytecount) {
217 		device_printf(request->dev,
218 		    "FAILURE - zero length DMA transfer attempted\n");
219 		return EIO;
220 	}
221 	if (((uintptr_t)(request->data) & (ch->dma.alignment - 1)) ||
222 	    (request->bytecount & (ch->dma.alignment - 1))) {
223 		device_printf(request->dev,
224 		    "FAILURE - non aligned DMA transfer attempted\n");
225 		return EIO;
226 	}
227 	if (request->bytecount > ch->dma.max_iosize) {
228 		device_printf(request->dev,
229 		    "FAILURE - oversized DMA transfer attempt %d > %d\n",
230 		    request->bytecount, ch->dma.max_iosize);
231 		return EIO;
232 	}
233 
234 	request->dma = &ch->dma.slot[0];
235 
236 	if ((error = bus_dmamap_load(request->dma->data_tag,
237 	    request->dma->data_map, request->data, request->bytecount,
238 	    &ata_dbdma_setprd, &args, BUS_DMA_NOWAIT))) {
239 		device_printf(request->dev, "FAILURE - load data\n");
240 		goto error;
241 	}
242 
243 	if (entries)
244 		*entries = args.nsegs;
245 
246 	bus_dmamap_sync(request->dma->sg_tag, request->dma->sg_map,
247 	    BUS_DMASYNC_PREWRITE);
248 	bus_dmamap_sync(request->dma->data_tag, request->dma->data_map,
249 	    (request->flags & ATA_R_READ) ?
250 	    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
251 
252 	return 0;
253 
254 error:
255 	ch->dma.unload(request);
256 	return EIO;
257 }
258 
259 void
260 ata_dbdma_dmainit(device_t dev)
261 {
262 	struct ata_dbdma_channel *sc = device_get_softc(dev);
263 
264 	dbdma_allocate_channel(sc->dbdma_regs, sc->dbdma_offset,
265 	    bus_get_dma_tag(dev), 256, &sc->dbdma);
266 
267 	dbdma_set_wait_selector(sc->dbdma,1 << 7, 1 << 7);
268 
269 	dbdma_insert_stop(sc->dbdma,0);
270 	sc->next_dma_slot=1;
271 
272 	sc->sc_ch.dma.start = ata_dbdma_start;
273 	sc->sc_ch.dma.stop = ata_dbdma_stop;
274 	sc->sc_ch.dma.load = ata_dbdma_load;
275 	sc->sc_ch.dma.reset = ata_dbdma_reset;
276 
277 	/*
278 	 * DBDMA's field for transfer size is 16 bits. This will overflow
279 	 * if we try to do a 64K transfer, so stop short of 64K.
280 	 */
281 	sc->sc_ch.dma.segsize = 126 * DEV_BSIZE;
282 	ata_dmainit(dev);
283 
284 	sc->sc_ch.hw.status = ata_dbdma_status;
285 
286 	mtx_init(&sc->dbdma_mtx, "ATA DBDMA", NULL, MTX_DEF);
287 }
288