xref: /openbmc/qemu/hw/block/m25p80.c (revision 1b111dc1)
1 /*
2  * ST M25P80 emulator. Emulate all SPI flash devices based on the m25p80 command
3  * set. Known devices table current as of Jun/2012 and taken from linux.
4  * See drivers/mtd/devices/m25p80.c.
5  *
6  * Copyright (C) 2011 Edgar E. Iglesias <edgar.iglesias@gmail.com>
7  * Copyright (C) 2012 Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
8  * Copyright (C) 2012 PetaLogix
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 or
13  * (at your option) a later version of the License.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License along
21  * with this program; if not, see <http://www.gnu.org/licenses/>.
22  */
23 
24 #include "hw/hw.h"
25 #include "sysemu/blockdev.h"
26 #include "hw/ssi.h"
27 
28 #ifndef M25P80_ERR_DEBUG
29 #define M25P80_ERR_DEBUG 0
30 #endif
31 
32 #define DB_PRINT_L(level, ...) do { \
33     if (M25P80_ERR_DEBUG > (level)) { \
34         fprintf(stderr,  ": %s: ", __func__); \
35         fprintf(stderr, ## __VA_ARGS__); \
36     } \
37 } while (0);
38 
39 /* Fields for FlashPartInfo->flags */
40 
41 /* erase capabilities */
42 #define ER_4K 1
43 #define ER_32K 2
44 /* set to allow the page program command to write 0s back to 1. Useful for
45  * modelling EEPROM with SPI flash command set
46  */
47 #define WR_1 0x100
48 
49 typedef struct FlashPartInfo {
50     const char *part_name;
51     /* jedec code. (jedec >> 16) & 0xff is the 1st byte, >> 8 the 2nd etc */
52     uint32_t jedec;
53     /* extended jedec code */
54     uint16_t ext_jedec;
55     /* there is confusion between manufacturers as to what a sector is. In this
56      * device model, a "sector" is the size that is erased by the ERASE_SECTOR
57      * command (opcode 0xd8).
58      */
59     uint32_t sector_size;
60     uint32_t n_sectors;
61     uint32_t page_size;
62     uint8_t flags;
63 } FlashPartInfo;
64 
65 /* adapted from linux */
66 
67 #define INFO(_part_name, _jedec, _ext_jedec, _sector_size, _n_sectors, _flags)\
68     .part_name = (_part_name),\
69     .jedec = (_jedec),\
70     .ext_jedec = (_ext_jedec),\
71     .sector_size = (_sector_size),\
72     .n_sectors = (_n_sectors),\
73     .page_size = 256,\
74     .flags = (_flags),\
75 
76 #define JEDEC_NUMONYX 0x20
77 #define JEDEC_WINBOND 0xEF
78 #define JEDEC_SPANSION 0x01
79 
80 static const FlashPartInfo known_devices[] = {
81     /* Atmel -- some are (confusingly) marketed as "DataFlash" */
82     { INFO("at25fs010",   0x1f6601,      0,  32 << 10,   4, ER_4K) },
83     { INFO("at25fs040",   0x1f6604,      0,  64 << 10,   8, ER_4K) },
84 
85     { INFO("at25df041a",  0x1f4401,      0,  64 << 10,   8, ER_4K) },
86     { INFO("at25df321a",  0x1f4701,      0,  64 << 10,  64, ER_4K) },
87     { INFO("at25df641",   0x1f4800,      0,  64 << 10, 128, ER_4K) },
88 
89     { INFO("at26f004",    0x1f0400,      0,  64 << 10,   8, ER_4K) },
90     { INFO("at26df081a",  0x1f4501,      0,  64 << 10,  16, ER_4K) },
91     { INFO("at26df161a",  0x1f4601,      0,  64 << 10,  32, ER_4K) },
92     { INFO("at26df321",   0x1f4700,      0,  64 << 10,  64, ER_4K) },
93 
94     { INFO("at45db081d",  0x1f2500,      0,  64 << 10,  16, ER_4K) },
95 
96     /* EON -- en25xxx */
97     { INFO("en25f32",     0x1c3116,      0,  64 << 10,  64, ER_4K) },
98     { INFO("en25p32",     0x1c2016,      0,  64 << 10,  64, 0) },
99     { INFO("en25q32b",    0x1c3016,      0,  64 << 10,  64, 0) },
100     { INFO("en25p64",     0x1c2017,      0,  64 << 10, 128, 0) },
101     { INFO("en25q64",     0x1c3017,      0,  64 << 10, 128, ER_4K) },
102 
103     /* GigaDevice */
104     { INFO("gd25q32",     0xc84016,      0,  64 << 10,  64, ER_4K) },
105     { INFO("gd25q64",     0xc84017,      0,  64 << 10, 128, ER_4K) },
106 
107     /* Intel/Numonyx -- xxxs33b */
108     { INFO("160s33b",     0x898911,      0,  64 << 10,  32, 0) },
109     { INFO("320s33b",     0x898912,      0,  64 << 10,  64, 0) },
110     { INFO("640s33b",     0x898913,      0,  64 << 10, 128, 0) },
111     { INFO("n25q064",     0x20ba17,      0,  64 << 10, 128, 0) },
112 
113     /* Macronix */
114     { INFO("mx25l2005a",  0xc22012,      0,  64 << 10,   4, ER_4K) },
115     { INFO("mx25l4005a",  0xc22013,      0,  64 << 10,   8, ER_4K) },
116     { INFO("mx25l8005",   0xc22014,      0,  64 << 10,  16, 0) },
117     { INFO("mx25l1606e",  0xc22015,      0,  64 << 10,  32, ER_4K) },
118     { INFO("mx25l3205d",  0xc22016,      0,  64 << 10,  64, 0) },
119     { INFO("mx25l6405d",  0xc22017,      0,  64 << 10, 128, 0) },
120     { INFO("mx25l12805d", 0xc22018,      0,  64 << 10, 256, 0) },
121     { INFO("mx25l12855e", 0xc22618,      0,  64 << 10, 256, 0) },
122     { INFO("mx25l25635e", 0xc22019,      0,  64 << 10, 512, 0) },
123     { INFO("mx25l25655e", 0xc22619,      0,  64 << 10, 512, 0) },
124 
125     /* Micron */
126     { INFO("n25q032a11",  0x20bb16,      0,  64 << 10,  64, ER_4K) },
127     { INFO("n25q032a13",  0x20ba16,      0,  64 << 10,  64, ER_4K) },
128     { INFO("n25q064a11",  0x20bb17,      0,  64 << 10, 128, ER_4K) },
129     { INFO("n25q064a13",  0x20ba17,      0,  64 << 10, 128, ER_4K) },
130     { INFO("n25q128a11",  0x20bb18,      0,  64 << 10, 256, ER_4K) },
131     { INFO("n25q128a13",  0x20ba18,      0,  64 << 10, 256, ER_4K) },
132     { INFO("n25q256a11",  0x20bb19,      0,  64 << 10, 512, ER_4K) },
133     { INFO("n25q256a13",  0x20ba19,      0,  64 << 10, 512, ER_4K) },
134 
135     /* Spansion -- single (large) sector size only, at least
136      * for the chips listed here (without boot sectors).
137      */
138     { INFO("s25sl032p",   0x010215, 0x4d00,  64 << 10,  64, ER_4K) },
139     { INFO("s25sl064p",   0x010216, 0x4d00,  64 << 10, 128, ER_4K) },
140     { INFO("s25fl256s0",  0x010219, 0x4d00, 256 << 10, 128, 0) },
141     { INFO("s25fl256s1",  0x010219, 0x4d01,  64 << 10, 512, 0) },
142     { INFO("s25fl512s",   0x010220, 0x4d00, 256 << 10, 256, 0) },
143     { INFO("s70fl01gs",   0x010221, 0x4d00, 256 << 10, 256, 0) },
144     { INFO("s25sl12800",  0x012018, 0x0300, 256 << 10,  64, 0) },
145     { INFO("s25sl12801",  0x012018, 0x0301,  64 << 10, 256, 0) },
146     { INFO("s25fl129p0",  0x012018, 0x4d00, 256 << 10,  64, 0) },
147     { INFO("s25fl129p1",  0x012018, 0x4d01,  64 << 10, 256, 0) },
148     { INFO("s25sl004a",   0x010212,      0,  64 << 10,   8, 0) },
149     { INFO("s25sl008a",   0x010213,      0,  64 << 10,  16, 0) },
150     { INFO("s25sl016a",   0x010214,      0,  64 << 10,  32, 0) },
151     { INFO("s25sl032a",   0x010215,      0,  64 << 10,  64, 0) },
152     { INFO("s25sl064a",   0x010216,      0,  64 << 10, 128, 0) },
153     { INFO("s25fl016k",   0xef4015,      0,  64 << 10,  32, ER_4K | ER_32K) },
154     { INFO("s25fl064k",   0xef4017,      0,  64 << 10, 128, ER_4K | ER_32K) },
155 
156     /* SST -- large erase sizes are "overlays", "sectors" are 4<< 10 */
157     { INFO("sst25vf040b", 0xbf258d,      0,  64 << 10,   8, ER_4K) },
158     { INFO("sst25vf080b", 0xbf258e,      0,  64 << 10,  16, ER_4K) },
159     { INFO("sst25vf016b", 0xbf2541,      0,  64 << 10,  32, ER_4K) },
160     { INFO("sst25vf032b", 0xbf254a,      0,  64 << 10,  64, ER_4K) },
161     { INFO("sst25wf512",  0xbf2501,      0,  64 << 10,   1, ER_4K) },
162     { INFO("sst25wf010",  0xbf2502,      0,  64 << 10,   2, ER_4K) },
163     { INFO("sst25wf020",  0xbf2503,      0,  64 << 10,   4, ER_4K) },
164     { INFO("sst25wf040",  0xbf2504,      0,  64 << 10,   8, ER_4K) },
165 
166     /* ST Microelectronics -- newer production may have feature updates */
167     { INFO("m25p05",      0x202010,      0,  32 << 10,   2, 0) },
168     { INFO("m25p10",      0x202011,      0,  32 << 10,   4, 0) },
169     { INFO("m25p20",      0x202012,      0,  64 << 10,   4, 0) },
170     { INFO("m25p40",      0x202013,      0,  64 << 10,   8, 0) },
171     { INFO("m25p80",      0x202014,      0,  64 << 10,  16, 0) },
172     { INFO("m25p16",      0x202015,      0,  64 << 10,  32, 0) },
173     { INFO("m25p32",      0x202016,      0,  64 << 10,  64, 0) },
174     { INFO("m25p64",      0x202017,      0,  64 << 10, 128, 0) },
175     { INFO("m25p128",     0x202018,      0, 256 << 10,  64, 0) },
176     { INFO("n25q032",     0x20ba16,      0,  64 << 10,  64, 0) },
177 
178     { INFO("m45pe10",     0x204011,      0,  64 << 10,   2, 0) },
179     { INFO("m45pe80",     0x204014,      0,  64 << 10,  16, 0) },
180     { INFO("m45pe16",     0x204015,      0,  64 << 10,  32, 0) },
181 
182     { INFO("m25pe20",     0x208012,      0,  64 << 10,   4, 0) },
183     { INFO("m25pe80",     0x208014,      0,  64 << 10,  16, 0) },
184     { INFO("m25pe16",     0x208015,      0,  64 << 10,  32, ER_4K) },
185 
186     { INFO("m25px32",     0x207116,      0,  64 << 10,  64, ER_4K) },
187     { INFO("m25px32-s0",  0x207316,      0,  64 << 10,  64, ER_4K) },
188     { INFO("m25px32-s1",  0x206316,      0,  64 << 10,  64, ER_4K) },
189     { INFO("m25px64",     0x207117,      0,  64 << 10, 128, 0) },
190 
191     /* Winbond -- w25x "blocks" are 64k, "sectors" are 4KiB */
192     { INFO("w25x10",      0xef3011,      0,  64 << 10,   2, ER_4K) },
193     { INFO("w25x20",      0xef3012,      0,  64 << 10,   4, ER_4K) },
194     { INFO("w25x40",      0xef3013,      0,  64 << 10,   8, ER_4K) },
195     { INFO("w25x80",      0xef3014,      0,  64 << 10,  16, ER_4K) },
196     { INFO("w25x16",      0xef3015,      0,  64 << 10,  32, ER_4K) },
197     { INFO("w25x32",      0xef3016,      0,  64 << 10,  64, ER_4K) },
198     { INFO("w25q32",      0xef4016,      0,  64 << 10,  64, ER_4K) },
199     { INFO("w25q32dw",    0xef6016,      0,  64 << 10,  64, ER_4K) },
200     { INFO("w25x64",      0xef3017,      0,  64 << 10, 128, ER_4K) },
201     { INFO("w25q64",      0xef4017,      0,  64 << 10, 128, ER_4K) },
202     { INFO("w25q80",      0xef5014,      0,  64 << 10,  16, ER_4K) },
203     { INFO("w25q80bl",    0xef4014,      0,  64 << 10,  16, ER_4K) },
204     { INFO("w25q256",     0xef4019,      0,  64 << 10, 512, ER_4K) },
205 
206     /* Numonyx -- n25q128 */
207     { INFO("n25q128",      0x20ba18,      0,  64 << 10, 256, 0) },
208 };
209 
210 typedef enum {
211     NOP = 0,
212     WRSR = 0x1,
213     WRDI = 0x4,
214     RDSR = 0x5,
215     WREN = 0x6,
216     JEDEC_READ = 0x9f,
217     BULK_ERASE = 0xc7,
218 
219     READ = 0x3,
220     FAST_READ = 0xb,
221     DOR = 0x3b,
222     QOR = 0x6b,
223     DIOR = 0xbb,
224     QIOR = 0xeb,
225 
226     PP = 0x2,
227     DPP = 0xa2,
228     QPP = 0x32,
229 
230     ERASE_4K = 0x20,
231     ERASE_32K = 0x52,
232     ERASE_SECTOR = 0xd8,
233 } FlashCMD;
234 
235 typedef enum {
236     STATE_IDLE,
237     STATE_PAGE_PROGRAM,
238     STATE_READ,
239     STATE_COLLECTING_DATA,
240     STATE_READING_DATA,
241 } CMDState;
242 
243 typedef struct Flash {
244     SSISlave ssidev;
245     uint32_t r;
246 
247     BlockDriverState *bdrv;
248 
249     uint8_t *storage;
250     uint32_t size;
251     int page_size;
252 
253     uint8_t state;
254     uint8_t data[16];
255     uint32_t len;
256     uint32_t pos;
257     uint8_t needed_bytes;
258     uint8_t cmd_in_progress;
259     uint64_t cur_addr;
260     bool write_enable;
261 
262     int64_t dirty_page;
263 
264     const FlashPartInfo *pi;
265 
266 } Flash;
267 
268 typedef struct M25P80Class {
269     SSISlaveClass parent_class;
270     FlashPartInfo *pi;
271 } M25P80Class;
272 
273 #define TYPE_M25P80 "m25p80-generic"
274 #define M25P80(obj) \
275      OBJECT_CHECK(Flash, (obj), TYPE_M25P80)
276 #define M25P80_CLASS(klass) \
277      OBJECT_CLASS_CHECK(M25P80Class, (klass), TYPE_M25P80)
278 #define M25P80_GET_CLASS(obj) \
279      OBJECT_GET_CLASS(M25P80Class, (obj), TYPE_M25P80)
280 
281 static void bdrv_sync_complete(void *opaque, int ret)
282 {
283     /* do nothing. Masters do not directly interact with the backing store,
284      * only the working copy so no mutexing required.
285      */
286 }
287 
288 static void flash_sync_page(Flash *s, int page)
289 {
290     if (s->bdrv) {
291         int bdrv_sector, nb_sectors;
292         QEMUIOVector iov;
293 
294         bdrv_sector = (page * s->pi->page_size) / BDRV_SECTOR_SIZE;
295         nb_sectors = DIV_ROUND_UP(s->pi->page_size, BDRV_SECTOR_SIZE);
296         qemu_iovec_init(&iov, 1);
297         qemu_iovec_add(&iov, s->storage + bdrv_sector * BDRV_SECTOR_SIZE,
298                                                 nb_sectors * BDRV_SECTOR_SIZE);
299         bdrv_aio_writev(s->bdrv, bdrv_sector, &iov, nb_sectors,
300                                                 bdrv_sync_complete, NULL);
301     }
302 }
303 
304 static inline void flash_sync_area(Flash *s, int64_t off, int64_t len)
305 {
306     int64_t start, end, nb_sectors;
307     QEMUIOVector iov;
308 
309     if (!s->bdrv) {
310         return;
311     }
312 
313     assert(!(len % BDRV_SECTOR_SIZE));
314     start = off / BDRV_SECTOR_SIZE;
315     end = (off + len) / BDRV_SECTOR_SIZE;
316     nb_sectors = end - start;
317     qemu_iovec_init(&iov, 1);
318     qemu_iovec_add(&iov, s->storage + (start * BDRV_SECTOR_SIZE),
319                                         nb_sectors * BDRV_SECTOR_SIZE);
320     bdrv_aio_writev(s->bdrv, start, &iov, nb_sectors, bdrv_sync_complete, NULL);
321 }
322 
323 static void flash_erase(Flash *s, int offset, FlashCMD cmd)
324 {
325     uint32_t len;
326     uint8_t capa_to_assert = 0;
327 
328     switch (cmd) {
329     case ERASE_4K:
330         len = 4 << 10;
331         capa_to_assert = ER_4K;
332         break;
333     case ERASE_32K:
334         len = 32 << 10;
335         capa_to_assert = ER_32K;
336         break;
337     case ERASE_SECTOR:
338         len = s->pi->sector_size;
339         break;
340     case BULK_ERASE:
341         len = s->size;
342         break;
343     default:
344         abort();
345     }
346 
347     DB_PRINT_L(0, "offset = %#x, len = %d\n", offset, len);
348     if ((s->pi->flags & capa_to_assert) != capa_to_assert) {
349         qemu_log_mask(LOG_GUEST_ERROR, "M25P80: %d erase size not supported by"
350                       " device\n", len);
351     }
352 
353     if (!s->write_enable) {
354         qemu_log_mask(LOG_GUEST_ERROR, "M25P80: erase with write protect!\n");
355         return;
356     }
357     memset(s->storage + offset, 0xff, len);
358     flash_sync_area(s, offset, len);
359 }
360 
361 static inline void flash_sync_dirty(Flash *s, int64_t newpage)
362 {
363     if (s->dirty_page >= 0 && s->dirty_page != newpage) {
364         flash_sync_page(s, s->dirty_page);
365         s->dirty_page = newpage;
366     }
367 }
368 
369 static inline
370 void flash_write8(Flash *s, uint64_t addr, uint8_t data)
371 {
372     int64_t page = addr / s->pi->page_size;
373     uint8_t prev = s->storage[s->cur_addr];
374 
375     if (!s->write_enable) {
376         qemu_log_mask(LOG_GUEST_ERROR, "M25P80: write with write protect!\n");
377     }
378 
379     if ((prev ^ data) & data) {
380         DB_PRINT_L(1, "programming zero to one! addr=%" PRIx64 "  %" PRIx8
381                    " -> %" PRIx8 "\n", addr, prev, data);
382     }
383 
384     if (s->pi->flags & WR_1) {
385         s->storage[s->cur_addr] = data;
386     } else {
387         s->storage[s->cur_addr] &= data;
388     }
389 
390     flash_sync_dirty(s, page);
391     s->dirty_page = page;
392 }
393 
394 static void complete_collecting_data(Flash *s)
395 {
396     s->cur_addr = s->data[0] << 16;
397     s->cur_addr |= s->data[1] << 8;
398     s->cur_addr |= s->data[2];
399 
400     s->state = STATE_IDLE;
401 
402     switch (s->cmd_in_progress) {
403     case DPP:
404     case QPP:
405     case PP:
406         s->state = STATE_PAGE_PROGRAM;
407         break;
408     case READ:
409     case FAST_READ:
410     case DOR:
411     case QOR:
412     case DIOR:
413     case QIOR:
414         s->state = STATE_READ;
415         break;
416     case ERASE_4K:
417     case ERASE_32K:
418     case ERASE_SECTOR:
419         flash_erase(s, s->cur_addr, s->cmd_in_progress);
420         break;
421     case WRSR:
422         if (s->write_enable) {
423             s->write_enable = false;
424         }
425         break;
426     default:
427         break;
428     }
429 }
430 
431 static void decode_new_cmd(Flash *s, uint32_t value)
432 {
433     s->cmd_in_progress = value;
434     DB_PRINT_L(0, "decoded new command:%x\n", value);
435 
436     switch (value) {
437 
438     case ERASE_4K:
439     case ERASE_32K:
440     case ERASE_SECTOR:
441     case READ:
442     case DPP:
443     case QPP:
444     case PP:
445         s->needed_bytes = 3;
446         s->pos = 0;
447         s->len = 0;
448         s->state = STATE_COLLECTING_DATA;
449         break;
450 
451     case FAST_READ:
452     case DOR:
453     case QOR:
454         s->needed_bytes = 4;
455         s->pos = 0;
456         s->len = 0;
457         s->state = STATE_COLLECTING_DATA;
458         break;
459 
460     case DIOR:
461         switch ((s->pi->jedec >> 16) & 0xFF) {
462         case JEDEC_WINBOND:
463         case JEDEC_SPANSION:
464             s->needed_bytes = 4;
465             break;
466         case JEDEC_NUMONYX:
467         default:
468             s->needed_bytes = 5;
469         }
470         s->pos = 0;
471         s->len = 0;
472         s->state = STATE_COLLECTING_DATA;
473         break;
474 
475     case QIOR:
476         switch ((s->pi->jedec >> 16) & 0xFF) {
477         case JEDEC_WINBOND:
478         case JEDEC_SPANSION:
479             s->needed_bytes = 6;
480             break;
481         case JEDEC_NUMONYX:
482         default:
483             s->needed_bytes = 8;
484         }
485         s->pos = 0;
486         s->len = 0;
487         s->state = STATE_COLLECTING_DATA;
488         break;
489 
490     case WRSR:
491         if (s->write_enable) {
492             s->needed_bytes = 1;
493             s->pos = 0;
494             s->len = 0;
495             s->state = STATE_COLLECTING_DATA;
496         }
497         break;
498 
499     case WRDI:
500         s->write_enable = false;
501         break;
502     case WREN:
503         s->write_enable = true;
504         break;
505 
506     case RDSR:
507         s->data[0] = (!!s->write_enable) << 1;
508         s->pos = 0;
509         s->len = 1;
510         s->state = STATE_READING_DATA;
511         break;
512 
513     case JEDEC_READ:
514         DB_PRINT_L(0, "populated jedec code\n");
515         s->data[0] = (s->pi->jedec >> 16) & 0xff;
516         s->data[1] = (s->pi->jedec >> 8) & 0xff;
517         s->data[2] = s->pi->jedec & 0xff;
518         if (s->pi->ext_jedec) {
519             s->data[3] = (s->pi->ext_jedec >> 8) & 0xff;
520             s->data[4] = s->pi->ext_jedec & 0xff;
521             s->len = 5;
522         } else {
523             s->len = 3;
524         }
525         s->pos = 0;
526         s->state = STATE_READING_DATA;
527         break;
528 
529     case BULK_ERASE:
530         if (s->write_enable) {
531             DB_PRINT_L(0, "chip erase\n");
532             flash_erase(s, 0, BULK_ERASE);
533         } else {
534             qemu_log_mask(LOG_GUEST_ERROR, "M25P80: chip erase with write "
535                           "protect!\n");
536         }
537         break;
538     case NOP:
539         break;
540     default:
541         qemu_log_mask(LOG_GUEST_ERROR, "M25P80: Unknown cmd %x\n", value);
542         break;
543     }
544 }
545 
546 static int m25p80_cs(SSISlave *ss, bool select)
547 {
548     Flash *s = FROM_SSI_SLAVE(Flash, ss);
549 
550     if (select) {
551         s->len = 0;
552         s->pos = 0;
553         s->state = STATE_IDLE;
554         flash_sync_dirty(s, -1);
555     }
556 
557     DB_PRINT_L(0, "%sselect\n", select ? "de" : "");
558 
559     return 0;
560 }
561 
562 static uint32_t m25p80_transfer8(SSISlave *ss, uint32_t tx)
563 {
564     Flash *s = FROM_SSI_SLAVE(Flash, ss);
565     uint32_t r = 0;
566 
567     switch (s->state) {
568 
569     case STATE_PAGE_PROGRAM:
570         DB_PRINT_L(1, "page program cur_addr=%#" PRIx64 " data=%" PRIx8 "\n",
571                    s->cur_addr, (uint8_t)tx);
572         flash_write8(s, s->cur_addr, (uint8_t)tx);
573         s->cur_addr++;
574         break;
575 
576     case STATE_READ:
577         r = s->storage[s->cur_addr];
578         DB_PRINT_L(1, "READ 0x%" PRIx64 "=%" PRIx8 "\n", s->cur_addr,
579                    (uint8_t)r);
580         s->cur_addr = (s->cur_addr + 1) % s->size;
581         break;
582 
583     case STATE_COLLECTING_DATA:
584         s->data[s->len] = (uint8_t)tx;
585         s->len++;
586 
587         if (s->len == s->needed_bytes) {
588             complete_collecting_data(s);
589         }
590         break;
591 
592     case STATE_READING_DATA:
593         r = s->data[s->pos];
594         s->pos++;
595         if (s->pos == s->len) {
596             s->pos = 0;
597             s->state = STATE_IDLE;
598         }
599         break;
600 
601     default:
602     case STATE_IDLE:
603         decode_new_cmd(s, (uint8_t)tx);
604         break;
605     }
606 
607     return r;
608 }
609 
610 static int m25p80_init(SSISlave *ss)
611 {
612     DriveInfo *dinfo;
613     Flash *s = FROM_SSI_SLAVE(Flash, ss);
614     M25P80Class *mc = M25P80_GET_CLASS(s);
615 
616     s->pi = mc->pi;
617 
618     s->size = s->pi->sector_size * s->pi->n_sectors;
619     s->dirty_page = -1;
620     s->storage = qemu_blockalign(s->bdrv, s->size);
621 
622     dinfo = drive_get_next(IF_MTD);
623 
624     if (dinfo && dinfo->bdrv) {
625         DB_PRINT_L(0, "Binding to IF_MTD drive\n");
626         s->bdrv = dinfo->bdrv;
627         if (bdrv_is_read_only(s->bdrv)) {
628             fprintf(stderr, "Can't use a read-only drive");
629             return 1;
630         }
631 
632         /* FIXME: Move to late init */
633         if (bdrv_read(s->bdrv, 0, s->storage, DIV_ROUND_UP(s->size,
634                                                     BDRV_SECTOR_SIZE))) {
635             fprintf(stderr, "Failed to initialize SPI flash!\n");
636             return 1;
637         }
638     } else {
639         DB_PRINT_L(0, "No BDRV - binding to RAM\n");
640         memset(s->storage, 0xFF, s->size);
641     }
642 
643     return 0;
644 }
645 
646 static void m25p80_pre_save(void *opaque)
647 {
648     flash_sync_dirty((Flash *)opaque, -1);
649 }
650 
651 static const VMStateDescription vmstate_m25p80 = {
652     .name = "xilinx_spi",
653     .version_id = 1,
654     .minimum_version_id = 1,
655     .minimum_version_id_old = 1,
656     .pre_save = m25p80_pre_save,
657     .fields = (VMStateField[]) {
658         VMSTATE_UINT8(state, Flash),
659         VMSTATE_UINT8_ARRAY(data, Flash, 16),
660         VMSTATE_UINT32(len, Flash),
661         VMSTATE_UINT32(pos, Flash),
662         VMSTATE_UINT8(needed_bytes, Flash),
663         VMSTATE_UINT8(cmd_in_progress, Flash),
664         VMSTATE_UINT64(cur_addr, Flash),
665         VMSTATE_BOOL(write_enable, Flash),
666         VMSTATE_END_OF_LIST()
667     }
668 };
669 
670 static void m25p80_class_init(ObjectClass *klass, void *data)
671 {
672     DeviceClass *dc = DEVICE_CLASS(klass);
673     SSISlaveClass *k = SSI_SLAVE_CLASS(klass);
674     M25P80Class *mc = M25P80_CLASS(klass);
675 
676     k->init = m25p80_init;
677     k->transfer = m25p80_transfer8;
678     k->set_cs = m25p80_cs;
679     k->cs_polarity = SSI_CS_LOW;
680     dc->vmsd = &vmstate_m25p80;
681     mc->pi = data;
682 }
683 
684 static const TypeInfo m25p80_info = {
685     .name           = TYPE_M25P80,
686     .parent         = TYPE_SSI_SLAVE,
687     .instance_size  = sizeof(Flash),
688     .class_size     = sizeof(M25P80Class),
689     .abstract       = true,
690 };
691 
692 static void m25p80_register_types(void)
693 {
694     int i;
695 
696     type_register_static(&m25p80_info);
697     for (i = 0; i < ARRAY_SIZE(known_devices); ++i) {
698         TypeInfo ti = {
699             .name       = known_devices[i].part_name,
700             .parent     = TYPE_M25P80,
701             .class_init = m25p80_class_init,
702             .class_data = (void *)&known_devices[i],
703         };
704         type_register(&ti);
705     }
706 }
707 
708 type_init(m25p80_register_types)
709