xref: /freebsd/sys/powerpc/powernv/opal_flash.c (revision 4b9d6057)
1 /*-
2  * Copyright (c) 2019 Justin Hibbits
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  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/systm.h>
28 #include <sys/bio.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/kthread.h>
32 #include <sys/lock.h>
33 #include <sys/module.h>
34 #include <sys/mutex.h>
35 #include <sys/proc.h>
36 #include <geom/geom_disk.h>
37 
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 
41 #include <dev/ofw/ofw_bus.h>
42 #include <dev/ofw/ofw_bus_subr.h>
43 #include <dev/ofw/openfirm.h>
44 #include "opal.h"
45 
46 /*
47  * OPAL System flash driver, using OPAL firmware calls to access the device.
48  *
49  * This just presents the base block interface.  The fdt_slicer can be used on
50  * top to present the partitions listed in the fdt.
51  *
52  * There are three OPAL methods used: OPAL_FLASH_READ, OPAL_FLASH_WRITE, and
53  * OPAL_FLASH_ERASE.  At the firmware layer, READ and WRITE can be on arbitrary
54  * boundaries, but ERASE is only at flash-block-size block alignments and sizes.
55  * To account for this, the following restrictions are in place:
56  *
57  * - Reads are on a 512-byte block boundary and size
58  * - Writes and Erases are aligned and sized on flash-block-size bytes.
59  *
60  * In order to support the fdt_slicer we present a type attribute of
61  * NAND::device.
62  */
63 struct opalflash_softc {
64 	device_t		 sc_dev;
65 	struct mtx		 sc_mtx;
66 	struct disk		*sc_disk;
67 	struct proc		*sc_p;
68 	struct bio_queue_head	 sc_bio_queue;
69 	int		 	 sc_opal_id;
70 	bool			 sc_erase; /* Erase is needed before write. */
71 };
72 
73 #define	OPALFLASH_LOCK(sc)		mtx_lock(&(sc)->sc_mtx)
74 #define	OPALFLASH_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
75 #define	OPALFLASH_LOCK_INIT(sc) \
76 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->sc_dev), \
77 	    "opalflash", MTX_DEF)
78 
79 #define	FLASH_BLOCKSIZE			512
80 
81 static int	opalflash_probe(device_t);
82 static int	opalflash_attach(device_t);
83 
84 static device_method_t  opalflash_methods[] = {
85 	/* Device interface */
86 	DEVMETHOD(device_probe,		opalflash_probe),
87 	DEVMETHOD(device_attach,	opalflash_attach),
88 
89 	DEVMETHOD_END
90 };
91 
92 static driver_t opalflash_driver = {
93 	"opalflash",
94 	opalflash_methods,
95 	sizeof(struct opalflash_softc)
96 };
97 
98 DRIVER_MODULE(opalflash, opal, opalflash_driver, 0, 0);
99 
100 /* GEOM Disk interfaces. */
101 static int
102 opalflash_open(struct disk *dp)
103 {
104 
105 	return (0);
106 }
107 
108 static int
109 opalflash_close(struct disk *dp)
110 {
111 
112 	return (0);
113 }
114 
115 static int
116 opalflash_ioctl(struct disk *dp, u_long cmd, void *data, int fflag,
117 	struct thread *td)
118 {
119 
120 	return (EINVAL);
121 }
122 
123 /* Handle the one attribute we need to play nice with geom_flashmap. */
124 static int
125 opalflash_getattr(struct bio *bp)
126 {
127 	struct opalflash_softc *sc;
128 	device_t dev;
129 
130 	if (bp->bio_disk == NULL || bp->bio_disk->d_drv1 == NULL)
131 		return (ENXIO);
132 
133 	sc = bp->bio_disk->d_drv1;
134 	dev = sc->sc_dev;
135 
136 	if (strcmp(bp->bio_attribute, "NAND::device") == 0) {
137 		if (bp->bio_length != sizeof(dev))
138 			return (EFAULT);
139 		bcopy(&dev, bp->bio_data, sizeof(dev));
140 	} else
141 		return (-1);
142 	return (0);
143 }
144 
145 static void
146 opalflash_strategy(struct bio *bp)
147 {
148 	struct opalflash_softc *sc;
149 
150 	sc = (struct opalflash_softc *)bp->bio_disk->d_drv1;
151 	OPALFLASH_LOCK(sc);
152 	bioq_disksort(&sc->sc_bio_queue, bp);
153 	wakeup(sc);
154 	OPALFLASH_UNLOCK(sc);
155 }
156 
157 static int
158 opalflash_read(struct opalflash_softc *sc, off_t off,
159     caddr_t data, off_t count)
160 {
161 	struct opal_msg msg;
162 	int rv, size, token;
163 
164 	/* Ensure we write aligned to a full block size. */
165 	if (off % sc->sc_disk->d_sectorsize != 0 ||
166 	    count % sc->sc_disk->d_sectorsize != 0)
167 		return (EIO);
168 
169 	token = opal_alloc_async_token();
170 
171 	/*
172 	 * Read one page at a time.  It's not guaranteed that the buffer is
173 	 * physically contiguous.
174 	 */
175 	rv = 0;
176 	while (count > 0) {
177 		size = MIN(count, PAGE_SIZE);
178 		size = MIN(size, PAGE_SIZE - ((u_long)data & PAGE_MASK));
179 		rv = opal_call(OPAL_FLASH_READ, sc->sc_opal_id, off,
180 		    vtophys(data), size, token);
181 		if (rv == OPAL_ASYNC_COMPLETION) {
182 			rv = opal_wait_completion(&msg, sizeof(msg), token);
183 			if (rv == OPAL_SUCCESS)
184 				rv = msg.params[1];
185 		}
186 		if (rv != OPAL_SUCCESS)
187 			break;
188 		count -= size;
189 		off += size;
190 		data += size;
191 	}
192 	opal_free_async_token(token);
193 	if (rv == OPAL_SUCCESS)
194 		rv = 0;
195 	else
196 		rv = EIO;
197 
198 	return (rv);
199 }
200 
201 static int
202 opalflash_erase(struct opalflash_softc *sc, off_t off, off_t count)
203 {
204 	struct opal_msg msg;
205 	int rv, token;
206 
207 	/* Ensure we write aligned to a full block size. */
208 	if (off % sc->sc_disk->d_stripesize != 0 ||
209 	    count % sc->sc_disk->d_stripesize != 0)
210 		return (EIO);
211 
212 	token = opal_alloc_async_token();
213 
214 	rv = opal_call(OPAL_FLASH_ERASE, sc->sc_opal_id, off, count, token);
215 	if (rv == OPAL_ASYNC_COMPLETION) {
216 		rv = opal_wait_completion(&msg, sizeof(msg), token);
217 		if (rv == OPAL_SUCCESS)
218 			rv = msg.params[1];
219 	}
220 	opal_free_async_token(token);
221 
222 	if (rv == OPAL_SUCCESS)
223 		rv = 0;
224 	else
225 		rv = EIO;
226 
227 	return (rv);
228 }
229 
230 static int
231 opalflash_write(struct opalflash_softc *sc, off_t off,
232     caddr_t data, off_t count)
233 {
234 	struct opal_msg msg;
235 	int rv, size, token;
236 
237 	/* Ensure we write aligned to a full block size. */
238 	if (off % sc->sc_disk->d_sectorsize != 0 ||
239 	    count % sc->sc_disk->d_sectorsize != 0)
240 		return (EIO);
241 
242 	if (sc->sc_erase) {
243 	    /* Erase the full block first, then write in page chunks. */
244 	    rv = opalflash_erase(sc, off, count);
245 	    if (rv != 0)
246 		    return (rv);
247 	}
248 
249 	token = opal_alloc_async_token();
250 
251 	/*
252 	 * Write one page at a time.  It's not guaranteed that the buffer is
253 	 * physically contiguous.
254 	 */
255 	while (count > 0) {
256 		size = MIN(count, PAGE_SIZE);
257 		size = MIN(size, PAGE_SIZE - ((u_long)data & PAGE_MASK));
258 		rv = opal_call(OPAL_FLASH_WRITE, sc->sc_opal_id, off,
259 		    vtophys(data), size, token);
260 		if (rv == OPAL_ASYNC_COMPLETION) {
261 			rv = opal_wait_completion(&msg, sizeof(msg), token);
262 			if (rv == OPAL_SUCCESS)
263 				rv = msg.params[1];
264 		}
265 		if (rv != OPAL_SUCCESS)
266 			break;
267 		count -= size;
268 		off += size;
269 		data += size;
270 	}
271 	opal_free_async_token(token);
272 
273 	if (rv == OPAL_SUCCESS)
274 		rv = 0;
275 	else
276 		rv = EIO;
277 
278 	return (rv);
279 }
280 
281 /* Main flash handling task. */
282 static void
283 opalflash_task(void *arg)
284 {
285 	struct opalflash_softc *sc;
286 	struct bio *bp;
287 
288 	sc = arg;
289 
290 	for (;;) {
291 		OPALFLASH_LOCK(sc);
292 		do {
293 			bp = bioq_first(&sc->sc_bio_queue);
294 			if (bp == NULL)
295 				msleep(sc, &sc->sc_mtx, PRIBIO, "opalflash", 0);
296 		} while (bp == NULL);
297 		bioq_remove(&sc->sc_bio_queue, bp);
298 		OPALFLASH_UNLOCK(sc);
299 
300 		switch (bp->bio_cmd) {
301 		case BIO_DELETE:
302 			bp->bio_error = opalflash_erase(sc, bp->bio_offset,
303 			    bp->bio_bcount);
304 			break;
305 		case BIO_READ:
306 			bp->bio_error = opalflash_read(sc, bp->bio_offset,
307 			    bp->bio_data, bp->bio_bcount);
308 			break;
309 		case BIO_WRITE:
310 			bp->bio_error = opalflash_write(sc, bp->bio_offset,
311 			    bp->bio_data, bp->bio_bcount);
312 			break;
313 		default:
314 			bp->bio_error = EINVAL;
315 		}
316 		biodone(bp);
317 	}
318 }
319 
320 /* Device driver interfaces. */
321 
322 static int
323 opalflash_probe(device_t dev)
324 {
325 	if (!ofw_bus_is_compatible(dev, "ibm,opal-flash"))
326 		return (ENXIO);
327 
328 	device_set_desc(dev, "OPAL System Flash");
329 
330 	return (BUS_PROBE_GENERIC);
331 }
332 
333 static int
334 opalflash_attach(device_t dev)
335 {
336 	struct opalflash_softc *sc;
337 	phandle_t node;
338 	cell_t flash_blocksize, opal_id;
339 	uint32_t regs[2];
340 
341 	sc = device_get_softc(dev);
342 	sc->sc_dev = dev;
343 
344 	node = ofw_bus_get_node(dev);
345 	OF_getencprop(node, "ibm,opal-id", &opal_id, sizeof(opal_id));
346 	sc->sc_opal_id = opal_id;
347 
348 	if (OF_getencprop(node, "ibm,flash-block-size",
349 	    &flash_blocksize, sizeof(flash_blocksize)) < 0) {
350 		device_printf(dev, "Cannot determine flash block size.\n");
351 		return (ENXIO);
352 	}
353 
354 	if (!OF_hasprop(node, "no-erase"))
355 		sc->sc_erase = true;
356 
357 	OPALFLASH_LOCK_INIT(sc);
358 
359 	if (OF_getencprop(node, "reg", regs, sizeof(regs)) < 0) {
360 		device_printf(dev, "Unable to get flash size.\n");
361 		return (ENXIO);
362 	}
363 
364 	sc->sc_disk = disk_alloc();
365 	sc->sc_disk->d_name = "opalflash";
366 	sc->sc_disk->d_open = opalflash_open;
367 	sc->sc_disk->d_close = opalflash_close;
368 	sc->sc_disk->d_strategy = opalflash_strategy;
369 	sc->sc_disk->d_ioctl = opalflash_ioctl;
370 	sc->sc_disk->d_getattr = opalflash_getattr;
371 	sc->sc_disk->d_drv1 = sc;
372 	sc->sc_disk->d_maxsize = DFLTPHYS;
373 	sc->sc_disk->d_mediasize = regs[1];
374 	sc->sc_disk->d_unit = device_get_unit(sc->sc_dev);
375 	sc->sc_disk->d_sectorsize = FLASH_BLOCKSIZE;
376 	    sc->sc_disk->d_stripesize = flash_blocksize;
377 	sc->sc_disk->d_dump = NULL;
378 
379 	disk_create(sc->sc_disk, DISK_VERSION);
380 	bioq_init(&sc->sc_bio_queue);
381 
382 	kproc_create(&opalflash_task, sc, &sc->sc_p, 0, 0, "task: OPAL Flash");
383 
384 	return (0);
385 }
386