xref: /freebsd/sys/powerpc/powernv/opal_flash.c (revision e17f5b1d307b7b8910d67883e57a9604305906d5)
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/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bio.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/kthread.h>
35 #include <sys/lock.h>
36 #include <sys/module.h>
37 #include <sys/mutex.h>
38 #include <sys/proc.h>
39 #include <geom/geom_disk.h>
40 
41 #include <vm/vm.h>
42 #include <vm/pmap.h>
43 
44 #include <dev/ofw/ofw_bus.h>
45 #include <dev/ofw/ofw_bus_subr.h>
46 #include <dev/ofw/openfirm.h>
47 #include "opal.h"
48 
49 /*
50  * OPAL System flash driver, using OPAL firmware calls to access the device.
51  *
52  * This just presents the base block interface.  The fdt_slicer can be used on
53  * top to present the partitions listed in the fdt.
54  *
55  * There are three OPAL methods used: OPAL_FLASH_READ, OPAL_FLASH_WRITE, and
56  * OPAL_FLASH_ERASE.  At the firmware layer, READ and WRITE can be on arbitrary
57  * boundaries, but ERASE is only at flash-block-size block alignments and sizes.
58  * To account for this, the following restrictions are in place:
59  *
60  * - Reads are on a 512-byte block boundary and size
61  * - Writes and Erases are aligned and sized on flash-block-size bytes.
62  *
63  * In order to support the fdt_slicer we present a type attribute of
64  * NAND::device.
65  */
66 struct opalflash_softc {
67 	device_t		 sc_dev;
68 	struct mtx		 sc_mtx;
69 	struct disk		*sc_disk;
70 	struct proc		*sc_p;
71 	struct bio_queue_head	 sc_bio_queue;
72 	int		 	 sc_opal_id;
73 	bool			 sc_erase; /* Erase is needed before write. */
74 };
75 
76 #define	OPALFLASH_LOCK(sc)		mtx_lock(&(sc)->sc_mtx)
77 #define	OPALFLASH_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
78 #define	OPALFLASH_LOCK_INIT(sc) \
79 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->sc_dev), \
80 	    "opalflash", MTX_DEF)
81 
82 #define	FLASH_BLOCKSIZE			512
83 
84 static int	opalflash_probe(device_t);
85 static int	opalflash_attach(device_t);
86 
87 static device_method_t  opalflash_methods[] = {
88 	/* Device interface */
89 	DEVMETHOD(device_probe,		opalflash_probe),
90 	DEVMETHOD(device_attach,	opalflash_attach),
91 
92 	DEVMETHOD_END
93 };
94 
95 static driver_t opalflash_driver = {
96 	"opalflash",
97 	opalflash_methods,
98 	sizeof(struct opalflash_softc)
99 };
100 
101 static devclass_t opalflash_devclass;
102 
103 DRIVER_MODULE(opalflash, opal, opalflash_driver, opalflash_devclass, 0, 0);
104 
105 /* GEOM Disk interfaces. */
106 static int
107 opalflash_open(struct disk *dp)
108 {
109 
110 	return (0);
111 }
112 
113 static int
114 opalflash_close(struct disk *dp)
115 {
116 
117 	return (0);
118 }
119 
120 static int
121 opalflash_ioctl(struct disk *dp, u_long cmd, void *data, int fflag,
122 	struct thread *td)
123 {
124 
125 	return (EINVAL);
126 }
127 
128 /* Handle the one attribute we need to play nice with geom_flashmap. */
129 static int
130 opalflash_getattr(struct bio *bp)
131 {
132 	struct opalflash_softc *sc;
133 	device_t dev;
134 
135 	if (bp->bio_disk == NULL || bp->bio_disk->d_drv1 == NULL)
136 		return (ENXIO);
137 
138 	sc = bp->bio_disk->d_drv1;
139 	dev = sc->sc_dev;
140 
141 	if (strcmp(bp->bio_attribute, "NAND::device") == 0) {
142 		if (bp->bio_length != sizeof(dev))
143 			return (EFAULT);
144 		bcopy(&dev, bp->bio_data, sizeof(dev));
145 	} else
146 		return (-1);
147 	return (0);
148 }
149 
150 static void
151 opalflash_strategy(struct bio *bp)
152 {
153 	struct opalflash_softc *sc;
154 
155 	sc = (struct opalflash_softc *)bp->bio_disk->d_drv1;
156 	OPALFLASH_LOCK(sc);
157 	bioq_disksort(&sc->sc_bio_queue, bp);
158 	wakeup(sc);
159 	OPALFLASH_UNLOCK(sc);
160 }
161 
162 static int
163 opalflash_read(struct opalflash_softc *sc, off_t off,
164     caddr_t data, off_t count)
165 {
166 	struct opal_msg msg;
167 	int rv, size, token;
168 
169 	/* Ensure we write aligned to a full block size. */
170 	if (off % sc->sc_disk->d_sectorsize != 0 ||
171 	    count % sc->sc_disk->d_sectorsize != 0)
172 		return (EIO);
173 
174 	token = opal_alloc_async_token();
175 
176 	/*
177 	 * Read one page at a time.  It's not guaranteed that the buffer is
178 	 * physically contiguous.
179 	 */
180 	rv = 0;
181 	while (count > 0) {
182 		size = MIN(count, PAGE_SIZE);
183 		size = MIN(size, PAGE_SIZE - ((u_long)data & PAGE_MASK));
184 		rv = opal_call(OPAL_FLASH_READ, sc->sc_opal_id, off,
185 		    vtophys(data), size, token);
186 		if (rv == OPAL_ASYNC_COMPLETION) {
187 			rv = opal_wait_completion(&msg, sizeof(msg), token);
188 			if (rv == OPAL_SUCCESS)
189 				rv = msg.params[1];
190 		}
191 		if (rv != OPAL_SUCCESS)
192 			break;
193 		count -= size;
194 		off += size;
195 		data += size;
196 	}
197 	opal_free_async_token(token);
198 	if (rv == OPAL_SUCCESS)
199 		rv = 0;
200 	else
201 		rv = EIO;
202 
203 	return (rv);
204 }
205 
206 static int
207 opalflash_erase(struct opalflash_softc *sc, off_t off, off_t count)
208 {
209 	struct opal_msg msg;
210 	int rv, token;
211 
212 	/* Ensure we write aligned to a full block size. */
213 	if (off % sc->sc_disk->d_stripesize != 0 ||
214 	    count % sc->sc_disk->d_stripesize != 0)
215 		return (EIO);
216 
217 	token = opal_alloc_async_token();
218 
219 	rv = opal_call(OPAL_FLASH_ERASE, sc->sc_opal_id, off, count, token);
220 	if (rv == OPAL_ASYNC_COMPLETION) {
221 		rv = opal_wait_completion(&msg, sizeof(msg), token);
222 		if (rv == OPAL_SUCCESS)
223 			rv = msg.params[1];
224 	}
225 	opal_free_async_token(token);
226 
227 	if (rv == OPAL_SUCCESS)
228 		rv = 0;
229 	else
230 		rv = EIO;
231 
232 	return (rv);
233 }
234 
235 static int
236 opalflash_write(struct opalflash_softc *sc, off_t off,
237     caddr_t data, off_t count)
238 {
239 	struct opal_msg msg;
240 	int rv, size, token;
241 
242 	/* Ensure we write aligned to a full block size. */
243 	if (off % sc->sc_disk->d_sectorsize != 0 ||
244 	    count % sc->sc_disk->d_sectorsize != 0)
245 		return (EIO);
246 
247 	if (sc->sc_erase) {
248 	    /* Erase the full block first, then write in page chunks. */
249 	    rv = opalflash_erase(sc, off, count);
250 	    if (rv != 0)
251 		    return (rv);
252 	}
253 
254 	token = opal_alloc_async_token();
255 
256 	/*
257 	 * Write one page at a time.  It's not guaranteed that the buffer is
258 	 * physically contiguous.
259 	 */
260 	while (count > 0) {
261 		size = MIN(count, PAGE_SIZE);
262 		size = MIN(size, PAGE_SIZE - ((u_long)data & PAGE_MASK));
263 		rv = opal_call(OPAL_FLASH_WRITE, sc->sc_opal_id, off,
264 		    vtophys(data), size, token);
265 		if (rv == OPAL_ASYNC_COMPLETION) {
266 			rv = opal_wait_completion(&msg, sizeof(msg), token);
267 			if (rv == OPAL_SUCCESS)
268 				rv = msg.params[1];
269 		}
270 		if (rv != OPAL_SUCCESS)
271 			break;
272 		count -= size;
273 		off += size;
274 		data += size;
275 	}
276 	opal_free_async_token(token);
277 
278 	if (rv == OPAL_SUCCESS)
279 		rv = 0;
280 	else
281 		rv = EIO;
282 
283 	return (rv);
284 }
285 
286 /* Main flash handling task. */
287 static void
288 opalflash_task(void *arg)
289 {
290 	struct opalflash_softc *sc;
291 	struct bio *bp;
292 	device_t dev;
293 
294 	sc = arg;
295 
296 	for (;;) {
297 		dev = sc->sc_dev;
298 		OPALFLASH_LOCK(sc);
299 		do {
300 			bp = bioq_first(&sc->sc_bio_queue);
301 			if (bp == NULL)
302 				msleep(sc, &sc->sc_mtx, PRIBIO, "opalflash", 0);
303 		} while (bp == NULL);
304 		bioq_remove(&sc->sc_bio_queue, bp);
305 		OPALFLASH_UNLOCK(sc);
306 
307 		switch (bp->bio_cmd) {
308 		case BIO_DELETE:
309 			bp->bio_error = opalflash_erase(sc, bp->bio_offset,
310 			    bp->bio_bcount);
311 			break;
312 		case BIO_READ:
313 			bp->bio_error = opalflash_read(sc, bp->bio_offset,
314 			    bp->bio_data, bp->bio_bcount);
315 			break;
316 		case BIO_WRITE:
317 			bp->bio_error = opalflash_write(sc, bp->bio_offset,
318 			    bp->bio_data, bp->bio_bcount);
319 			break;
320 		default:
321 			bp->bio_error = EINVAL;
322 		}
323 		biodone(bp);
324 	}
325 }
326 
327 
328 /* Device driver interfaces. */
329 
330 static int
331 opalflash_probe(device_t dev)
332 {
333 	if (!ofw_bus_is_compatible(dev, "ibm,opal-flash"))
334 		return (ENXIO);
335 
336 	device_set_desc(dev, "OPAL System Flash");
337 
338 	return (BUS_PROBE_GENERIC);
339 }
340 
341 static int
342 opalflash_attach(device_t dev)
343 {
344 	struct opalflash_softc *sc;
345 	phandle_t node;
346 	cell_t flash_blocksize, opal_id;
347 	uint32_t regs[2];
348 
349 	sc = device_get_softc(dev);
350 	sc->sc_dev = dev;
351 
352 	node = ofw_bus_get_node(dev);
353 	OF_getencprop(node, "ibm,opal-id", &opal_id, sizeof(opal_id));
354 	sc->sc_opal_id = opal_id;
355 
356 	if (OF_getencprop(node, "ibm,flash-block-size",
357 	    &flash_blocksize, sizeof(flash_blocksize)) < 0) {
358 		device_printf(dev, "Cannot determine flash block size.\n");
359 		return (ENXIO);
360 	}
361 
362 	if (!OF_hasprop(node, "no-erase"))
363 		sc->sc_erase = true;
364 
365 	OPALFLASH_LOCK_INIT(sc);
366 
367 	if (OF_getencprop(node, "reg", regs, sizeof(regs)) < 0) {
368 		device_printf(dev, "Unable to get flash size.\n");
369 		return (ENXIO);
370 	}
371 
372 	sc->sc_disk = disk_alloc();
373 	sc->sc_disk->d_name = "opalflash";
374 	sc->sc_disk->d_open = opalflash_open;
375 	sc->sc_disk->d_close = opalflash_close;
376 	sc->sc_disk->d_strategy = opalflash_strategy;
377 	sc->sc_disk->d_ioctl = opalflash_ioctl;
378 	sc->sc_disk->d_getattr = opalflash_getattr;
379 	sc->sc_disk->d_drv1 = sc;
380 	sc->sc_disk->d_maxsize = DFLTPHYS;
381 	sc->sc_disk->d_mediasize = regs[1];
382 	sc->sc_disk->d_unit = device_get_unit(sc->sc_dev);
383 	sc->sc_disk->d_sectorsize = FLASH_BLOCKSIZE;
384 	    sc->sc_disk->d_stripesize = flash_blocksize;
385 	sc->sc_disk->d_dump = NULL;
386 
387 	disk_create(sc->sc_disk, DISK_VERSION);
388 	bioq_init(&sc->sc_bio_queue);
389 
390 	kproc_create(&opalflash_task, sc, &sc->sc_p, 0, 0, "task: OPAL Flash");
391 
392 	return (0);
393 }
394