1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2012 Robert N. M. Watson
5 * All rights reserved.
6 *
7 * This software was developed by SRI International and the University of
8 * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
9 * ("CTSRD"), as part of the DARPA CRASH research programme.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include <sys/cdefs.h>
34 #include <sys/param.h>
35 #include <sys/bus.h>
36 #include <sys/condvar.h>
37 #include <sys/conf.h>
38 #include <sys/bio.h>
39 #include <sys/endian.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/malloc.h>
43 #include <sys/module.h>
44 #include <sys/mutex.h>
45 #include <sys/rman.h>
46 #include <sys/systm.h>
47 #include <sys/taskqueue.h>
48
49 #include <machine/bus.h>
50 #include <machine/resource.h>
51
52 #include <geom/geom_disk.h>
53
54 #include <dev/altera/sdcard/altera_sdcard.h>
55
56 int altera_sdcard_ignore_crc_errors = 1;
57 int altera_sdcard_verify_rxtx_writes = 1;
58
59 /*
60 * Low-level I/O routines for the Altera SD Card University IP Core driver.
61 *
62 * XXXRW: Throughout, it is assumed that the IP Core handles multibyte
63 * registers as little endian, as is the case for other Altera IP cores.
64 * However, the specification makes no reference to endianness, so this
65 * assumption might not always be correct.
66 */
67 uint16_t
altera_sdcard_read_asr(struct altera_sdcard_softc * sc)68 altera_sdcard_read_asr(struct altera_sdcard_softc *sc)
69 {
70
71 return (le16toh(bus_read_2(sc->as_res, ALTERA_SDCARD_OFF_ASR)));
72 }
73
74 static int
altera_sdcard_process_csd0(struct altera_sdcard_softc * sc)75 altera_sdcard_process_csd0(struct altera_sdcard_softc *sc)
76 {
77 uint64_t c_size, c_size_mult, read_bl_len;
78 uint8_t byte0, byte1, byte2;
79
80 ALTERA_SDCARD_LOCK_ASSERT(sc);
81
82 /*-
83 * Compute card capacity per SD Card interface description as follows:
84 *
85 * Memory capacity = BLOCKNR * BLOCK_LEN
86 *
87 * Where:
88 *
89 * BLOCKNR = (C_SIZE + 1) * MULT
90 * MULT = 2^(C_SIZE_MULT+2)
91 * BLOCK_LEN = 2^READ_BL_LEN
92 */
93 read_bl_len = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_READ_BL_LEN_BYTE];
94 read_bl_len &= ALTERA_SDCARD_CSD_READ_BL_LEN_MASK;
95
96 byte0 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_BYTE0];
97 byte0 &= ALTERA_SDCARD_CSD_C_SIZE_MASK0;
98 byte1 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_BYTE1];
99 byte2 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_BYTE2];
100 byte2 &= ALTERA_SDCARD_CSD_C_SIZE_MASK2;
101 c_size = (byte0 >> ALTERA_SDCARD_CSD_C_SIZE_RSHIFT0) |
102 (byte1 << ALTERA_SDCARD_CSD_C_SIZE_LSHIFT1) |
103 (byte2 << ALTERA_SDCARD_CSD_C_SIZE_LSHIFT2);
104
105 byte0 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_MULT_BYTE0];
106 byte0 &= ALTERA_SDCARD_CSD_C_SIZE_MULT_MASK0;
107 byte1 = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_C_SIZE_MULT_BYTE1];
108 byte1 &= ALTERA_SDCARD_CSD_C_SIZE_MULT_MASK1;
109 c_size_mult = (byte0 >> ALTERA_SDCARD_CSD_C_SIZE_MULT_RSHIFT0) |
110 (byte1 << ALTERA_SDCARD_CSD_C_SIZE_MULT_LSHIFT1);
111
112 /*
113 * If we're just getting back zero's, mark the card as bad, even
114 * though it could just mean a Very Small Disk Indeed.
115 */
116 if (c_size == 0 && c_size_mult == 0 && read_bl_len == 0) {
117 device_printf(sc->as_dev, "Ignored zero-size card\n");
118 return (ENXIO);
119 }
120 sc->as_mediasize = (c_size + 1) * (1 << (c_size_mult + 2)) *
121 (1 << read_bl_len);
122 return (0);
123 }
124
125 int
altera_sdcard_read_csd(struct altera_sdcard_softc * sc)126 altera_sdcard_read_csd(struct altera_sdcard_softc *sc)
127 {
128 uint8_t csd_structure;
129 int error;
130
131 ALTERA_SDCARD_LOCK_ASSERT(sc);
132
133 /*
134 * XXXRW: Assume for now that when the SD Card IP Core negotiates
135 * voltage/speed/etc, it must use the CSD register, and therefore
136 * populates the SD Card IP Core's cache of the register value. This
137 * means that we can read it without issuing further SD Card commands.
138 * If this assumption proves false, we will (a) get back garbage and
139 * (b) need to add additional states in the driver state machine in
140 * order to query card properties before I/O can start.
141 *
142 * XXXRW: Treating this as an array of bytes, so no byte swapping --
143 * is that a safe assumption?
144 */
145 KASSERT(((uintptr_t)&sc->as_csd.csd_data) % 2 == 0,
146 ("%s: CSD buffer unaligned", __func__));
147 bus_read_region_2(sc->as_res, ALTERA_SDCARD_OFF_CSD,
148 (uint16_t *)sc->as_csd.csd_data, sizeof(sc->as_csd) / 2);
149
150 /*
151 * Interpret the loaded CSD, extracting certain fields and copying
152 * them into the softc for easy software access.
153 *
154 * Currently, we support only CSD Version 1.0. If we detect a newer
155 * version, suppress card detection.
156 */
157 csd_structure = sc->as_csd.csd_data[ALTERA_SDCARD_CSD_STRUCTURE_BYTE];
158 csd_structure &= ALTERA_SDCARD_CSD_STRUCTURE_MASK;
159 csd_structure >>= ALTERA_SDCARD_CSD_STRUCTURE_RSHIFT;
160 sc->as_csd_structure = csd_structure;
161
162 /*
163 * Interpret the CSD field based on its version. Extract fields,
164 * especially mediasize.
165 *
166 * XXXRW: Desirable to support further CSD versions here.
167 */
168 switch (sc->as_csd_structure) {
169 case 0:
170 error = altera_sdcard_process_csd0(sc);
171 if (error)
172 return (error);
173 break;
174
175 default:
176 device_printf(sc->as_dev,
177 "Ignored disk with unsupported CSD structure (%d)\n",
178 sc->as_csd_structure);
179 return (ENXIO);
180 }
181 return (0);
182 }
183
184 /*
185 * XXXRW: The Altera IP Core specification indicates that RR1 is a 16-bit
186 * register, but all bits it identifies are >16 bit. Most likely, RR1 is a
187 * 32-bit register?
188 */
189 static uint16_t
altera_sdcard_read_rr1(struct altera_sdcard_softc * sc)190 altera_sdcard_read_rr1(struct altera_sdcard_softc *sc)
191 {
192
193 return (le16toh(bus_read_2(sc->as_res, ALTERA_SDCARD_OFF_RR1)));
194 }
195
196 static void
altera_sdcard_write_cmd_arg(struct altera_sdcard_softc * sc,uint32_t cmd_arg)197 altera_sdcard_write_cmd_arg(struct altera_sdcard_softc *sc, uint32_t cmd_arg)
198 {
199
200 bus_write_4(sc->as_res, ALTERA_SDCARD_OFF_CMD_ARG, htole32(cmd_arg));
201 }
202
203 static void
altera_sdcard_write_cmd(struct altera_sdcard_softc * sc,uint16_t cmd)204 altera_sdcard_write_cmd(struct altera_sdcard_softc *sc, uint16_t cmd)
205 {
206
207 bus_write_2(sc->as_res, ALTERA_SDCARD_OFF_CMD, htole16(cmd));
208 }
209
210 static void
altera_sdcard_read_rxtx_buffer(struct altera_sdcard_softc * sc,void * data,size_t len)211 altera_sdcard_read_rxtx_buffer(struct altera_sdcard_softc *sc, void *data,
212 size_t len)
213 {
214
215 KASSERT((uintptr_t)data % 2 == 0,
216 ("%s: unaligned data %p", __func__, data));
217 KASSERT((len <= ALTERA_SDCARD_SECTORSIZE) && (len % 2 == 0),
218 ("%s: invalid length %ju", __func__, len));
219
220 bus_read_region_2(sc->as_res, ALTERA_SDCARD_OFF_RXTX_BUFFER,
221 (uint16_t *)data, len / 2);
222 }
223
224 static void
altera_sdcard_write_rxtx_buffer(struct altera_sdcard_softc * sc,void * data,size_t len)225 altera_sdcard_write_rxtx_buffer(struct altera_sdcard_softc *sc, void *data,
226 size_t len)
227 {
228 u_int corrections, differences, i, retry_counter;
229 uint16_t d, v;
230
231 KASSERT((uintptr_t)data % 2 == 0,
232 ("%s: unaligned data %p", __func__, data));
233 KASSERT((len <= ALTERA_SDCARD_SECTORSIZE) && (len % 2 == 0),
234 ("%s: invalid length %ju", __func__, len));
235
236 retry_counter = 0;
237 do {
238 bus_write_region_2(sc->as_res, ALTERA_SDCARD_OFF_RXTX_BUFFER,
239 (uint16_t *)data, len / 2);
240
241 /*
242 * XXXRW: Due to a possible hardware bug, the above call to
243 * bus_write_region_2() might not succeed. If the workaround
244 * is enabled, verify each write and retry until it succeeds.
245 *
246 * XXXRW: Do we want a limit counter for retries here?
247 */
248 recheck:
249 corrections = 0;
250 differences = 0;
251 if (altera_sdcard_verify_rxtx_writes) {
252 for (i = 0; i < ALTERA_SDCARD_SECTORSIZE; i += 2) {
253 v = bus_read_2(sc->as_res,
254 ALTERA_SDCARD_OFF_RXTX_BUFFER + i);
255 d = *(uint16_t *)((uint8_t *)data + i);
256 if (v != d) {
257 if (retry_counter == 0) {
258 bus_write_2(sc->as_res,
259 ALTERA_SDCARD_OFF_RXTX_BUFFER + i,
260 d);
261 v = bus_read_2(sc->as_res,
262 ALTERA_SDCARD_OFF_RXTX_BUFFER + i);
263 if (v == d) {
264 corrections++;
265 device_printf(sc->as_dev,
266 "%s: single word rewrite worked"
267 " at offset %u\n",
268 __func__, i);
269 continue;
270 }
271 }
272 differences++;
273 device_printf(sc->as_dev,
274 "%s: retrying write -- difference"
275 " %u at offset %u, retry %u\n",
276 __func__, differences, i,
277 retry_counter);
278 }
279 }
280 if (differences != 0) {
281 retry_counter++;
282 if (retry_counter == 1 &&
283 corrections == differences)
284 goto recheck;
285 }
286 }
287 } while (differences != 0);
288 if (retry_counter)
289 device_printf(sc->as_dev, "%s: succeeded after %u retries\n",
290 __func__, retry_counter);
291 }
292
293 static void
altera_sdcard_io_start_internal(struct altera_sdcard_softc * sc,struct bio ** bpp)294 altera_sdcard_io_start_internal(struct altera_sdcard_softc *sc,
295 struct bio **bpp)
296 {
297 struct bio *bp;
298
299 bp = *bpp;
300
301 switch (bp->bio_cmd) {
302 case BIO_READ:
303 altera_sdcard_write_cmd_arg(sc, bp->bio_pblkno *
304 ALTERA_SDCARD_SECTORSIZE);
305 altera_sdcard_write_cmd(sc, ALTERA_SDCARD_CMD_READ_BLOCK);
306 break;
307
308 case BIO_WRITE:
309 altera_sdcard_write_rxtx_buffer(sc, bp->bio_data,
310 bp->bio_bcount);
311 altera_sdcard_write_cmd_arg(sc, bp->bio_pblkno *
312 ALTERA_SDCARD_SECTORSIZE);
313 altera_sdcard_write_cmd(sc, ALTERA_SDCARD_CMD_WRITE_BLOCK);
314 break;
315
316 default:
317 biofinish(bp, NULL, EOPNOTSUPP);
318 *bpp = NULL;
319 }
320 }
321
322 void
altera_sdcard_io_start(struct altera_sdcard_softc * sc,struct bio * bp)323 altera_sdcard_io_start(struct altera_sdcard_softc *sc, struct bio *bp)
324 {
325
326 ALTERA_SDCARD_LOCK_ASSERT(sc);
327 KASSERT(sc->as_currentbio == NULL,
328 ("%s: bio already started", __func__));
329
330 /*
331 * We advertise a block size and maximum I/O size up the stack of the
332 * SD Card IP Core sector size. Catch any attempts to not follow the
333 * rules.
334 */
335 KASSERT(bp->bio_bcount == ALTERA_SDCARD_SECTORSIZE,
336 ("%s: I/O size not %d", __func__, ALTERA_SDCARD_SECTORSIZE));
337 altera_sdcard_io_start_internal(sc, &bp);
338 sc->as_currentbio = bp;
339 sc->as_retriesleft = ALTERA_SDCARD_RETRY_LIMIT;
340 }
341
342 /*
343 * Handle completed I/O. ASR is passed in to avoid reading it more than once.
344 * Return 1 if the I/O is actually complete (success, or retry limit
345 * exceeded), or 0 if not.
346 */
347 int
altera_sdcard_io_complete(struct altera_sdcard_softc * sc,uint16_t asr)348 altera_sdcard_io_complete(struct altera_sdcard_softc *sc, uint16_t asr)
349 {
350 struct bio *bp;
351 uint16_t rr1, mask;
352 int error;
353
354 ALTERA_SDCARD_LOCK_ASSERT(sc);
355 KASSERT(!(asr & ALTERA_SDCARD_ASR_CMDINPROGRESS),
356 ("%s: still in progress", __func__));
357 KASSERT(asr & ALTERA_SDCARD_ASR_CARDPRESENT,
358 ("%s: card removed", __func__));
359
360 bp = sc->as_currentbio;
361
362 /*-
363 * Handle I/O retries if an error is returned by the device. Various
364 * quirks handled in the process:
365 *
366 * 1. ALTERA_SDCARD_ASR_CMDDATAERROR is ignored for BIO_WRITE.
367 * 2. ALTERA_SDCARD_RR1_COMMANDCRCFAILED is optionally ignored for
368 * BIO_READ.
369 */
370 error = 0;
371 rr1 = altera_sdcard_read_rr1(sc);
372 switch (bp->bio_cmd) {
373 case BIO_READ:
374 mask = ALTERA_SDCARD_RR1_ERRORMASK;
375 if (altera_sdcard_ignore_crc_errors)
376 mask &= ~ALTERA_SDCARD_RR1_COMMANDCRCFAILED;
377 if (asr & ALTERA_SDCARD_ASR_CMDTIMEOUT)
378 error = EIO;
379 else if ((asr & ALTERA_SDCARD_ASR_CMDDATAERROR) &&
380 (rr1 & mask))
381 error = EIO;
382 else
383 error = 0;
384 break;
385
386 case BIO_WRITE:
387 if (asr & ALTERA_SDCARD_ASR_CMDTIMEOUT)
388 error = EIO;
389 else
390 error = 0;
391 break;
392
393 default:
394 break;
395 }
396 if (error) {
397 sc->as_retriesleft--;
398 if (sc->as_retriesleft == 0 || bootverbose)
399 device_printf(sc->as_dev, "%s: %s operation block %ju "
400 "length %ju failed; asr 0x%08x (rr1: 0x%04x)%s\n",
401 __func__, bp->bio_cmd == BIO_READ ? "BIO_READ" :
402 (bp->bio_cmd == BIO_WRITE ? "BIO_WRITE" :
403 "unknown"),
404 bp->bio_pblkno, bp->bio_bcount, asr, rr1,
405 sc->as_retriesleft != 0 ? " retrying" : "");
406 /*
407 * This attempt experienced an error; possibly retry.
408 */
409 if (sc->as_retriesleft != 0) {
410 sc->as_flags |= ALTERA_SDCARD_FLAG_IOERROR;
411 altera_sdcard_io_start_internal(sc, &bp);
412 return (0);
413 }
414 sc->as_flags &= ~ALTERA_SDCARD_FLAG_IOERROR;
415 } else {
416 /*
417 * Successful I/O completion path.
418 */
419 if (sc->as_flags & ALTERA_SDCARD_FLAG_IOERROR) {
420 device_printf(sc->as_dev, "%s: %s operation block %ju"
421 " length %ju succeeded after %d retries\n",
422 __func__, bp->bio_cmd == BIO_READ ? "BIO_READ" :
423 (bp->bio_cmd == BIO_WRITE ? "write" : "unknown"),
424 bp->bio_pblkno, bp->bio_bcount,
425 ALTERA_SDCARD_RETRY_LIMIT - sc->as_retriesleft);
426 sc->as_flags &= ~ALTERA_SDCARD_FLAG_IOERROR;
427 }
428 switch (bp->bio_cmd) {
429 case BIO_READ:
430 altera_sdcard_read_rxtx_buffer(sc, bp->bio_data,
431 bp->bio_bcount);
432 break;
433
434 case BIO_WRITE:
435 break;
436
437 default:
438 panic("%s: unsupported I/O operation %d", __func__,
439 bp->bio_cmd);
440 }
441 bp->bio_resid = 0;
442 error = 0;
443 }
444 biofinish(bp, NULL, error);
445 sc->as_currentbio = NULL;
446 return (1);
447 }
448