xref: /freebsd/sys/dev/cfi/cfi_dev.c (revision 685dc743dc3b5645e34836464128e1c0558b404b)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2007, Juniper Networks, Inc.
5  * Copyright (c) 2012-2013, SRI International
6  * All rights reserved.
7  *
8  * Portions of this software were developed by SRI International and the
9  * University of Cambridge Computer Laboratory under DARPA/AFRL contract
10  * (FA8750-10-C-0237) ("CTSRD"), as part of the DARPA CRASH research
11  * programme.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the author nor the names of any co-contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
30  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
31  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
32  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
33  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 #include "opt_cfi.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/bus.h>
44 #include <sys/conf.h>
45 #include <sys/ioccom.h>
46 #include <sys/kernel.h>
47 #include <sys/limits.h>
48 #include <sys/malloc.h>
49 #include <sys/proc.h>
50 #include <sys/sysctl.h>
51 #include <sys/types.h>
52 #include <sys/uio.h>
53 
54 #include <sys/cfictl.h>
55 
56 #include <machine/atomic.h>
57 #include <machine/bus.h>
58 
59 #include <dev/cfi/cfi_var.h>
60 
61 static d_open_t cfi_devopen;
62 static d_close_t cfi_devclose;
63 static d_read_t cfi_devread;
64 static d_write_t cfi_devwrite;
65 static d_ioctl_t cfi_devioctl;
66 
67 struct cdevsw cfi_cdevsw = {
68 	.d_version	=	D_VERSION,
69 	.d_flags	=	0,
70 	.d_name		=	cfi_driver_name,
71 	.d_open		=	cfi_devopen,
72 	.d_close	=	cfi_devclose,
73 	.d_read		=	cfi_devread,
74 	.d_write	=	cfi_devwrite,
75 	.d_ioctl	=	cfi_devioctl,
76 };
77 
78 /*
79  * Begin writing into a new block/sector.  We read the sector into
80  * memory and keep updating that, until we move into another sector
81  * or the process stops writing. At that time we write the whole
82  * sector to flash (see cfi_block_finish).  To avoid unneeded erase
83  * cycles, keep a pristine copy of the sector on hand.
84  */
85 int
cfi_block_start(struct cfi_softc * sc,u_int ofs)86 cfi_block_start(struct cfi_softc *sc, u_int ofs)
87 {
88 	union {
89 		uint8_t		*x8;
90 		uint16_t	*x16;
91 		uint32_t	*x32;
92 	} ptr;
93 	u_int rofs, rsz;
94 	uint32_t val;
95 	int r;
96 
97 	rofs = 0;
98 	for (r = 0; r < sc->sc_regions; r++) {
99 		rsz = sc->sc_region[r].r_blocks * sc->sc_region[r].r_blksz;
100 		if (ofs < rofs + rsz)
101 			break;
102 		rofs += rsz;
103 	}
104 	if (r == sc->sc_regions)
105 		return (EFAULT);
106 
107 	sc->sc_wrbufsz = sc->sc_region[r].r_blksz;
108 	sc->sc_wrbuf = malloc(sc->sc_wrbufsz, M_TEMP, M_WAITOK);
109 	sc->sc_wrofs = ofs - (ofs - rofs) % sc->sc_wrbufsz;
110 
111 	/* Read the block from flash for byte-serving. */
112 	ptr.x8 = sc->sc_wrbuf;
113 	for (r = 0; r < sc->sc_wrbufsz; r += sc->sc_width) {
114 		val = cfi_read_raw(sc, sc->sc_wrofs + r);
115 		switch (sc->sc_width) {
116 		case 1:
117 			*(ptr.x8)++ = val;
118 			break;
119 		case 2:
120 			*(ptr.x16)++ = val;
121 			break;
122 		case 4:
123 			*(ptr.x32)++ = val;
124 			break;
125 		}
126 	}
127 	sc->sc_wrbufcpy = malloc(sc->sc_wrbufsz, M_TEMP, M_WAITOK);
128 	memcpy(sc->sc_wrbufcpy, sc->sc_wrbuf, sc->sc_wrbufsz);
129 	sc->sc_writing = 1;
130 	return (0);
131 }
132 
133 /*
134  * Finish updating the current block/sector by writing the compound
135  * set of changes to the flash.
136  */
137 int
cfi_block_finish(struct cfi_softc * sc)138 cfi_block_finish(struct cfi_softc *sc)
139 {
140 	int error;
141 
142 	error = cfi_write_block(sc);
143 	free(sc->sc_wrbuf, M_TEMP);
144 	free(sc->sc_wrbufcpy, M_TEMP);
145 	sc->sc_wrbuf = NULL;
146 	sc->sc_wrbufsz = 0;
147 	sc->sc_wrofs = 0;
148 	sc->sc_writing = 0;
149 	return (error);
150 }
151 
152 static int
cfi_devopen(struct cdev * dev,int oflags,int devtype,struct thread * td)153 cfi_devopen(struct cdev *dev, int oflags, int devtype, struct thread *td)
154 {
155 	struct cfi_softc *sc;
156 
157 	sc = dev->si_drv1;
158 	/* We allow only 1 open. */
159 	if (!atomic_cmpset_acq_ptr((uintptr_t *)&sc->sc_opened,
160 	    (uintptr_t)NULL, (uintptr_t)td->td_proc))
161 		return (EBUSY);
162 	return (0);
163 }
164 
165 static int
cfi_devclose(struct cdev * dev,int fflag,int devtype,struct thread * td)166 cfi_devclose(struct cdev *dev, int fflag, int devtype, struct thread *td)
167 {
168 	struct cfi_softc *sc;
169 	int error;
170 
171 	sc = dev->si_drv1;
172 	/* Sanity. Not really necessary. */
173 	if (sc->sc_opened != td->td_proc)
174 		return (ENXIO);
175 
176 	error = (sc->sc_writing) ? cfi_block_finish(sc) : 0;
177 	sc->sc_opened = NULL;
178 	return (error);
179 }
180 
181 static int
cfi_devread(struct cdev * dev,struct uio * uio,int ioflag)182 cfi_devread(struct cdev *dev, struct uio *uio, int ioflag)
183 {
184 	union {
185 		uint8_t		x8[4];
186 		uint16_t	x16[2];
187 		uint32_t	x32[1];
188 	} buf;
189 	struct cfi_softc *sc;
190 	u_int ofs;
191 	uint32_t val;
192 	int error;
193 
194 	sc = dev->si_drv1;
195 
196 	error = (sc->sc_writing) ? cfi_block_finish(sc) : 0;
197 	if (!error)
198 		error = (uio->uio_offset > sc->sc_size) ? EIO : 0;
199 
200 	while (error == 0 && uio->uio_resid > 0 &&
201 	    uio->uio_offset < sc->sc_size) {
202 		ofs = uio->uio_offset;
203 		val = cfi_read_raw(sc, ofs);
204 		switch (sc->sc_width) {
205 		case 1:
206 			buf.x8[0] = val;
207 			break;
208 		case 2:
209 			buf.x16[0] = val;
210 			break;
211 		case 4:
212 			buf.x32[0] = val;
213 			break;
214 		}
215 		ofs &= sc->sc_width - 1;
216 		error = uiomove(buf.x8 + ofs,
217 		    MIN(uio->uio_resid, sc->sc_width - ofs), uio);
218 	}
219 	return (error);
220 }
221 
222 static int
cfi_devwrite(struct cdev * dev,struct uio * uio,int ioflag)223 cfi_devwrite(struct cdev *dev, struct uio *uio, int ioflag)
224 {
225 	struct cfi_softc *sc;
226 	u_int ofs, top;
227 	int error;
228 
229 	sc = dev->si_drv1;
230 
231 	error = (uio->uio_offset > sc->sc_size) ? EIO : 0;
232 	while (error == 0 && uio->uio_resid > 0 &&
233 	    uio->uio_offset < sc->sc_size) {
234 		ofs = uio->uio_offset;
235 
236 		/*
237 		 * Finish the current block if we're about to write
238 		 * to a different block.
239 		 */
240 		if (sc->sc_writing) {
241 			top = sc->sc_wrofs + sc->sc_wrbufsz;
242 			if (ofs < sc->sc_wrofs || ofs >= top)
243 				cfi_block_finish(sc);
244 		}
245 
246 		/* Start writing to a (new) block if applicable. */
247 		if (!sc->sc_writing) {
248 			error = cfi_block_start(sc, uio->uio_offset);
249 			if (error)
250 				break;
251 		}
252 
253 		top = sc->sc_wrofs + sc->sc_wrbufsz;
254 		error = uiomove(sc->sc_wrbuf + ofs - sc->sc_wrofs,
255 		    MIN(top - ofs, uio->uio_resid), uio);
256 	}
257 	return (error);
258 }
259 
260 static int
cfi_devioctl(struct cdev * dev,u_long cmd,caddr_t data,int fflag,struct thread * td)261 cfi_devioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
262     struct thread *td)
263 {
264 	struct cfi_softc *sc;
265 	struct cfiocqry *rq;
266 	int error;
267 	u_char val;
268 
269 	sc = dev->si_drv1;
270 	error = 0;
271 
272 	switch (cmd) {
273 	case CFIOCQRY:
274 		if (sc->sc_writing) {
275 			error = cfi_block_finish(sc);
276 			if (error)
277 				break;
278 		}
279 		rq = (struct cfiocqry *)data;
280 		if (rq->offset >= sc->sc_size / sc->sc_width)
281 			return (ESPIPE);
282 		if (rq->offset > ULONG_MAX - rq->count ||
283 		    rq->offset + rq->count > sc->sc_size / sc->sc_width)
284 			return (ENOSPC);
285 
286 		while (!error && rq->count--) {
287 			val = cfi_read_qry(sc, rq->offset++);
288 			error = copyout(&val, rq->buffer++, 1);
289 		}
290 		break;
291 #ifdef CFI_SUPPORT_STRATAFLASH
292 	case CFIOCGFACTORYPR:
293 		error = cfi_intel_get_factory_pr(sc, (uint64_t *)data);
294 		break;
295 	case CFIOCGOEMPR:
296 		error = cfi_intel_get_oem_pr(sc, (uint64_t *)data);
297 		break;
298 	case CFIOCSOEMPR:
299 		error = cfi_intel_set_oem_pr(sc, *(uint64_t *)data);
300 		break;
301 	case CFIOCGPLR:
302 		error = cfi_intel_get_plr(sc, (uint32_t *)data);
303 		break;
304 	case CFIOCSPLR:
305 		error = cfi_intel_set_plr(sc);
306 		break;
307 #endif /* CFI_SUPPORT_STRATAFLASH */
308 	default:
309 		error = ENOIOCTL;
310 		break;
311 	}
312 	return (error);
313 }
314