xref: /openbmc/qemu/hw/block/pflash_cfi02.c (revision 979a8902)
1 /*
2  *  CFI parallel flash with AMD command set emulation
3  *
4  *  Copyright (c) 2005 Jocelyn Mayer
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 /*
21  * For now, this code can emulate flashes of 1, 2 or 4 bytes width.
22  * Supported commands/modes are:
23  * - flash read
24  * - flash write
25  * - flash ID read
26  * - sector erase
27  * - chip erase
28  * - unlock bypass command
29  * - CFI queries
30  *
31  * It does not support flash interleaving.
32  * It does not implement software data protection as found in many real chips
33  */
34 
35 #include "qemu/osdep.h"
36 #include "hw/block/block.h"
37 #include "hw/block/flash.h"
38 #include "hw/qdev-properties.h"
39 #include "qapi/error.h"
40 #include "qemu/bitmap.h"
41 #include "qemu/timer.h"
42 #include "sysemu/block-backend.h"
43 #include "qemu/host-utils.h"
44 #include "qemu/module.h"
45 #include "hw/sysbus.h"
46 #include "migration/vmstate.h"
47 #include "trace.h"
48 
49 #define PFLASH_DEBUG false
50 #define DPRINTF(fmt, ...)                                  \
51 do {                                                       \
52     if (PFLASH_DEBUG) {                                    \
53         fprintf(stderr, "PFLASH: " fmt, ## __VA_ARGS__);   \
54     }                                                      \
55 } while (0)
56 
57 #define PFLASH_LAZY_ROMD_THRESHOLD 42
58 
59 /*
60  * The size of the cfi_table indirectly depends on this and the start of the
61  * PRI table directly depends on it. 4 is the maximum size (and also what
62  * seems common) without changing the PRT table address.
63  */
64 #define PFLASH_MAX_ERASE_REGIONS 4
65 
66 /* Special write cycles for CFI queries. */
67 enum {
68     WCYCLE_CFI              = 7,
69     WCYCLE_AUTOSELECT_CFI   = 8,
70 };
71 
72 struct PFlashCFI02 {
73     /*< private >*/
74     SysBusDevice parent_obj;
75     /*< public >*/
76 
77     BlockBackend *blk;
78     uint32_t uniform_nb_blocs;
79     uint32_t uniform_sector_len;
80     uint32_t total_sectors;
81     uint32_t nb_blocs[PFLASH_MAX_ERASE_REGIONS];
82     uint32_t sector_len[PFLASH_MAX_ERASE_REGIONS];
83     uint32_t chip_len;
84     uint8_t mappings;
85     uint8_t width;
86     uint8_t be;
87     int wcycle; /* if 0, the flash is read normally */
88     int bypass;
89     int ro;
90     uint8_t cmd;
91     uint8_t status;
92     /* FIXME: implement array device properties */
93     uint16_t ident0;
94     uint16_t ident1;
95     uint16_t ident2;
96     uint16_t ident3;
97     uint16_t unlock_addr0;
98     uint16_t unlock_addr1;
99     uint8_t cfi_table[0x4d];
100     QEMUTimer timer;
101     /* The device replicates the flash memory across its memory space.  Emulate
102      * that by having a container (.mem) filled with an array of aliases
103      * (.mem_mappings) pointing to the flash memory (.orig_mem).
104      */
105     MemoryRegion mem;
106     MemoryRegion *mem_mappings;    /* array; one per mapping */
107     MemoryRegion orig_mem;
108     int rom_mode;
109     int read_counter; /* used for lazy switch-back to rom mode */
110     int sectors_to_erase;
111     uint64_t erase_time_remaining;
112     unsigned long *sector_erase_map;
113     char *name;
114     void *storage;
115 };
116 
117 /*
118  * Toggle status bit DQ7.
119  */
120 static inline void toggle_dq7(PFlashCFI02 *pfl)
121 {
122     pfl->status ^= 0x80;
123 }
124 
125 /*
126  * Set status bit DQ7 to bit 7 of value.
127  */
128 static inline void set_dq7(PFlashCFI02 *pfl, uint8_t value)
129 {
130     pfl->status &= 0x7F;
131     pfl->status |= value & 0x80;
132 }
133 
134 /*
135  * Toggle status bit DQ6.
136  */
137 static inline void toggle_dq6(PFlashCFI02 *pfl)
138 {
139     pfl->status ^= 0x40;
140 }
141 
142 /*
143  * Turn on DQ3.
144  */
145 static inline void assert_dq3(PFlashCFI02 *pfl)
146 {
147     pfl->status |= 0x08;
148 }
149 
150 /*
151  * Turn off DQ3.
152  */
153 static inline void reset_dq3(PFlashCFI02 *pfl)
154 {
155     pfl->status &= ~0x08;
156 }
157 
158 /*
159  * Toggle status bit DQ2.
160  */
161 static inline void toggle_dq2(PFlashCFI02 *pfl)
162 {
163     pfl->status ^= 0x04;
164 }
165 
166 /*
167  * Set up replicated mappings of the same region.
168  */
169 static void pflash_setup_mappings(PFlashCFI02 *pfl)
170 {
171     unsigned i;
172     hwaddr size = memory_region_size(&pfl->orig_mem);
173 
174     memory_region_init(&pfl->mem, OBJECT(pfl), "pflash", pfl->mappings * size);
175     pfl->mem_mappings = g_new(MemoryRegion, pfl->mappings);
176     for (i = 0; i < pfl->mappings; ++i) {
177         memory_region_init_alias(&pfl->mem_mappings[i], OBJECT(pfl),
178                                  "pflash-alias", &pfl->orig_mem, 0, size);
179         memory_region_add_subregion(&pfl->mem, i * size, &pfl->mem_mappings[i]);
180     }
181 }
182 
183 static void pflash_register_memory(PFlashCFI02 *pfl, int rom_mode)
184 {
185     memory_region_rom_device_set_romd(&pfl->orig_mem, rom_mode);
186     pfl->rom_mode = rom_mode;
187 }
188 
189 static size_t pflash_regions_count(PFlashCFI02 *pfl)
190 {
191     return pfl->cfi_table[0x2c];
192 }
193 
194 /*
195  * Returns the time it takes to erase the number of sectors scheduled for
196  * erasure based on CFI address 0x21 which is "Typical timeout per individual
197  * block erase 2^N ms."
198  */
199 static uint64_t pflash_erase_time(PFlashCFI02 *pfl)
200 {
201     /*
202      * If there are no sectors to erase (which can happen if all of the sectors
203      * to be erased are protected), then erase takes 100 us. Protected sectors
204      * aren't supported so this should never happen.
205      */
206     return ((1ULL << pfl->cfi_table[0x21]) * pfl->sectors_to_erase) * SCALE_US;
207 }
208 
209 /*
210  * Returns true if the device is currently in erase suspend mode.
211  */
212 static inline bool pflash_erase_suspend_mode(PFlashCFI02 *pfl)
213 {
214     return pfl->erase_time_remaining > 0;
215 }
216 
217 static void pflash_timer(void *opaque)
218 {
219     PFlashCFI02 *pfl = opaque;
220 
221     trace_pflash_timer_expired(pfl->cmd);
222     if (pfl->cmd == 0x30) {
223         /*
224          * Sector erase. If DQ3 is 0 when the timer expires, then the 50
225          * us erase timeout has expired so we need to start the timer for the
226          * sector erase algorithm. Otherwise, the erase completed and we should
227          * go back to read array mode.
228          */
229         if ((pfl->status & 0x08) == 0) {
230             assert_dq3(pfl);
231             uint64_t timeout = pflash_erase_time(pfl);
232             timer_mod(&pfl->timer,
233                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
234             DPRINTF("%s: erase timeout fired; erasing %d sectors\n",
235                     __func__, pfl->sectors_to_erase);
236             return;
237         }
238         DPRINTF("%s: sector erase complete\n", __func__);
239         bitmap_zero(pfl->sector_erase_map, pfl->total_sectors);
240         pfl->sectors_to_erase = 0;
241         reset_dq3(pfl);
242     }
243 
244     /* Reset flash */
245     toggle_dq7(pfl);
246     if (pfl->bypass) {
247         pfl->wcycle = 2;
248     } else {
249         pflash_register_memory(pfl, 1);
250         pfl->wcycle = 0;
251     }
252     pfl->cmd = 0;
253 }
254 
255 /*
256  * Read data from flash.
257  */
258 static uint64_t pflash_data_read(PFlashCFI02 *pfl, hwaddr offset,
259                                  unsigned int width)
260 {
261     uint8_t *p = (uint8_t *)pfl->storage + offset;
262     uint64_t ret = pfl->be ? ldn_be_p(p, width) : ldn_le_p(p, width);
263     trace_pflash_data_read(offset, width, ret);
264     return ret;
265 }
266 
267 typedef struct {
268     uint32_t len;
269     uint32_t num;
270 } SectorInfo;
271 
272 /*
273  * offset should be a byte offset of the QEMU device and _not_ a device
274  * offset.
275  */
276 static SectorInfo pflash_sector_info(PFlashCFI02 *pfl, hwaddr offset)
277 {
278     assert(offset < pfl->chip_len);
279     hwaddr addr = 0;
280     uint32_t sector_num = 0;
281     for (int i = 0; i < pflash_regions_count(pfl); ++i) {
282         uint64_t region_size = (uint64_t)pfl->nb_blocs[i] * pfl->sector_len[i];
283         if (addr <= offset && offset < addr + region_size) {
284             return (SectorInfo) {
285                 .len = pfl->sector_len[i],
286                 .num = sector_num + (offset - addr) / pfl->sector_len[i],
287             };
288         }
289         sector_num += pfl->nb_blocs[i];
290         addr += region_size;
291     }
292     abort();
293 }
294 
295 /*
296  * Returns true if the offset refers to a flash sector that is currently being
297  * erased.
298  */
299 static bool pflash_sector_is_erasing(PFlashCFI02 *pfl, hwaddr offset)
300 {
301     long sector_num = pflash_sector_info(pfl, offset).num;
302     return test_bit(sector_num, pfl->sector_erase_map);
303 }
304 
305 static uint64_t pflash_read(void *opaque, hwaddr offset, unsigned int width)
306 {
307     PFlashCFI02 *pfl = opaque;
308     hwaddr boff;
309     uint64_t ret;
310 
311     ret = -1;
312     /* Lazy reset to ROMD mode after a certain amount of read accesses */
313     if (!pfl->rom_mode && pfl->wcycle == 0 &&
314         ++pfl->read_counter > PFLASH_LAZY_ROMD_THRESHOLD) {
315         pflash_register_memory(pfl, 1);
316     }
317     offset &= pfl->chip_len - 1;
318     boff = offset & 0xFF;
319     if (pfl->width == 2) {
320         boff = boff >> 1;
321     } else if (pfl->width == 4) {
322         boff = boff >> 2;
323     }
324     switch (pfl->cmd) {
325     default:
326         /* This should never happen : reset state & treat it as a read*/
327         DPRINTF("%s: unknown command state: %x\n", __func__, pfl->cmd);
328         pfl->wcycle = 0;
329         pfl->cmd = 0;
330         /* fall through to the read code */
331     case 0x80: /* Erase (unlock) */
332         /* We accept reads during second unlock sequence... */
333     case 0x00:
334         if (pflash_erase_suspend_mode(pfl) &&
335             pflash_sector_is_erasing(pfl, offset)) {
336             /* Toggle bit 2, but not 6. */
337             toggle_dq2(pfl);
338             /* Status register read */
339             ret = pfl->status;
340             DPRINTF("%s: status %" PRIx64 "\n", __func__, ret);
341             break;
342         }
343         /* Flash area read */
344         ret = pflash_data_read(pfl, offset, width);
345         break;
346     case 0x90: /* flash ID read */
347         switch (boff) {
348         case 0x00:
349         case 0x01:
350             ret = boff & 0x01 ? pfl->ident1 : pfl->ident0;
351             break;
352         case 0x02:
353             ret = 0x00; /* Pretend all sectors are unprotected */
354             break;
355         case 0x0E:
356         case 0x0F:
357             ret = boff & 0x01 ? pfl->ident3 : pfl->ident2;
358             if (ret != (uint8_t)-1) {
359                 break;
360             }
361             /* Fall through to data read. */
362         default:
363             ret = pflash_data_read(pfl, offset, width);
364         }
365         DPRINTF("%s: ID " TARGET_FMT_plx " %" PRIx64 "\n", __func__, boff, ret);
366         break;
367     case 0x10: /* Chip Erase */
368     case 0x30: /* Sector Erase */
369         /* Toggle bit 2 during erase, but not program. */
370         toggle_dq2(pfl);
371         /* fall through */
372     case 0xA0: /* Program */
373         /* Toggle bit 6 */
374         toggle_dq6(pfl);
375         /* Status register read */
376         ret = pfl->status;
377         DPRINTF("%s: status %" PRIx64 "\n", __func__, ret);
378         break;
379     case 0x98:
380         /* CFI query mode */
381         if (boff < sizeof(pfl->cfi_table)) {
382             ret = pfl->cfi_table[boff];
383         } else {
384             ret = 0;
385         }
386         break;
387     }
388     trace_pflash_io_read(offset, width, ret, pfl->cmd, pfl->wcycle);
389 
390     return ret;
391 }
392 
393 /* update flash content on disk */
394 static void pflash_update(PFlashCFI02 *pfl, int offset, int size)
395 {
396     int offset_end;
397     if (pfl->blk) {
398         offset_end = offset + size;
399         /* widen to sector boundaries */
400         offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
401         offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
402         blk_pwrite(pfl->blk, offset, pfl->storage + offset,
403                    offset_end - offset, 0);
404     }
405 }
406 
407 static void pflash_sector_erase(PFlashCFI02 *pfl, hwaddr offset)
408 {
409     SectorInfo sector_info = pflash_sector_info(pfl, offset);
410     uint64_t sector_len = sector_info.len;
411     offset &= ~(sector_len - 1);
412     DPRINTF("%s: start sector erase at %0*" PRIx64 "-%0*" PRIx64 "\n",
413             __func__, pfl->width * 2, offset,
414             pfl->width * 2, offset + sector_len - 1);
415     if (!pfl->ro) {
416         uint8_t *p = pfl->storage;
417         memset(p + offset, 0xff, sector_len);
418         pflash_update(pfl, offset, sector_len);
419     }
420     set_dq7(pfl, 0x00);
421     ++pfl->sectors_to_erase;
422     set_bit(sector_info.num, pfl->sector_erase_map);
423     /* Set (or reset) the 50 us timer for additional erase commands.  */
424     timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 50000);
425 }
426 
427 static void pflash_write(void *opaque, hwaddr offset, uint64_t value,
428                          unsigned int width)
429 {
430     PFlashCFI02 *pfl = opaque;
431     hwaddr boff;
432     uint8_t *p;
433     uint8_t cmd;
434 
435     trace_pflash_io_write(offset, width, value, pfl->wcycle);
436     cmd = value;
437     if (pfl->cmd != 0xA0) {
438         /* Reset does nothing during chip erase and sector erase. */
439         if (cmd == 0xF0 && pfl->cmd != 0x10 && pfl->cmd != 0x30) {
440             if (pfl->wcycle == WCYCLE_AUTOSELECT_CFI) {
441                 /* Return to autoselect mode. */
442                 pfl->wcycle = 3;
443                 pfl->cmd = 0x90;
444                 return;
445             }
446             goto reset_flash;
447         }
448     }
449     offset &= pfl->chip_len - 1;
450 
451     boff = offset;
452     if (pfl->width == 2) {
453         boff = boff >> 1;
454     } else if (pfl->width == 4) {
455         boff = boff >> 2;
456     }
457     /* Only the least-significant 11 bits are used in most cases. */
458     boff &= 0x7FF;
459     switch (pfl->wcycle) {
460     case 0:
461         /* Set the device in I/O access mode if required */
462         if (pfl->rom_mode)
463             pflash_register_memory(pfl, 0);
464         pfl->read_counter = 0;
465         /* We're in read mode */
466     check_unlock0:
467         if (boff == 0x55 && cmd == 0x98) {
468             /* Enter CFI query mode */
469             pfl->wcycle = WCYCLE_CFI;
470             pfl->cmd = 0x98;
471             return;
472         }
473         /* Handle erase resume in erase suspend mode, otherwise reset. */
474         if (cmd == 0x30) { /* Erase Resume */
475             if (pflash_erase_suspend_mode(pfl)) {
476                 /* Resume the erase. */
477                 timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
478                           pfl->erase_time_remaining);
479                 pfl->erase_time_remaining = 0;
480                 pfl->wcycle = 6;
481                 pfl->cmd = 0x30;
482                 set_dq7(pfl, 0x00);
483                 assert_dq3(pfl);
484                 return;
485             }
486             goto reset_flash;
487         }
488         /* Ignore erase suspend. */
489         if (cmd == 0xB0) { /* Erase Suspend */
490             return;
491         }
492         if (boff != pfl->unlock_addr0 || cmd != 0xAA) {
493             DPRINTF("%s: unlock0 failed " TARGET_FMT_plx " %02x %04x\n",
494                     __func__, boff, cmd, pfl->unlock_addr0);
495             goto reset_flash;
496         }
497         DPRINTF("%s: unlock sequence started\n", __func__);
498         break;
499     case 1:
500         /* We started an unlock sequence */
501     check_unlock1:
502         if (boff != pfl->unlock_addr1 || cmd != 0x55) {
503             DPRINTF("%s: unlock1 failed " TARGET_FMT_plx " %02x\n", __func__,
504                     boff, cmd);
505             goto reset_flash;
506         }
507         DPRINTF("%s: unlock sequence done\n", __func__);
508         break;
509     case 2:
510         /* We finished an unlock sequence */
511         if (!pfl->bypass && boff != pfl->unlock_addr0) {
512             DPRINTF("%s: command failed " TARGET_FMT_plx " %02x\n", __func__,
513                     boff, cmd);
514             goto reset_flash;
515         }
516         switch (cmd) {
517         case 0x20:
518             pfl->bypass = 1;
519             goto do_bypass;
520         case 0x80: /* Erase */
521         case 0x90: /* Autoselect */
522         case 0xA0: /* Program */
523             pfl->cmd = cmd;
524             DPRINTF("%s: starting command %02x\n", __func__, cmd);
525             break;
526         default:
527             DPRINTF("%s: unknown command %02x\n", __func__, cmd);
528             goto reset_flash;
529         }
530         break;
531     case 3:
532         switch (pfl->cmd) {
533         case 0x80: /* Erase */
534             /* We need another unlock sequence */
535             goto check_unlock0;
536         case 0xA0: /* Program */
537             if (pflash_erase_suspend_mode(pfl) &&
538                 pflash_sector_is_erasing(pfl, offset)) {
539                 /* Ignore writes to erasing sectors. */
540                 if (pfl->bypass) {
541                     goto do_bypass;
542                 }
543                 goto reset_flash;
544             }
545             trace_pflash_data_write(offset, width, value, 0);
546             if (!pfl->ro) {
547                 p = (uint8_t *)pfl->storage + offset;
548                 if (pfl->be) {
549                     uint64_t current = ldn_be_p(p, width);
550                     stn_be_p(p, width, current & value);
551                 } else {
552                     uint64_t current = ldn_le_p(p, width);
553                     stn_le_p(p, width, current & value);
554                 }
555                 pflash_update(pfl, offset, width);
556             }
557             /*
558              * While programming, status bit DQ7 should hold the opposite
559              * value from how it was programmed.
560              */
561             set_dq7(pfl, ~value);
562             /* Let's pretend write is immediate */
563             if (pfl->bypass)
564                 goto do_bypass;
565             goto reset_flash;
566         case 0x90: /* Autoselect */
567             if (pfl->bypass && cmd == 0x00) {
568                 /* Unlock bypass reset */
569                 goto reset_flash;
570             }
571             /*
572              * We can enter CFI query mode from autoselect mode, but we must
573              * return to autoselect mode after a reset.
574              */
575             if (boff == 0x55 && cmd == 0x98) {
576                 /* Enter autoselect CFI query mode */
577                 pfl->wcycle = WCYCLE_AUTOSELECT_CFI;
578                 pfl->cmd = 0x98;
579                 return;
580             }
581             /* fall through */
582         default:
583             DPRINTF("%s: invalid write for command %02x\n",
584                     __func__, pfl->cmd);
585             goto reset_flash;
586         }
587     case 4:
588         switch (pfl->cmd) {
589         case 0xA0: /* Program */
590             /* Ignore writes while flash data write is occurring */
591             /* As we suppose write is immediate, this should never happen */
592             return;
593         case 0x80: /* Erase */
594             goto check_unlock1;
595         default:
596             /* Should never happen */
597             DPRINTF("%s: invalid command state %02x (wc 4)\n",
598                     __func__, pfl->cmd);
599             goto reset_flash;
600         }
601         break;
602     case 5:
603         if (pflash_erase_suspend_mode(pfl)) {
604             /* Erasing is not supported in erase suspend mode. */
605             goto reset_flash;
606         }
607         switch (cmd) {
608         case 0x10: /* Chip Erase */
609             if (boff != pfl->unlock_addr0) {
610                 DPRINTF("%s: chip erase: invalid address " TARGET_FMT_plx "\n",
611                         __func__, offset);
612                 goto reset_flash;
613             }
614             /* Chip erase */
615             DPRINTF("%s: start chip erase\n", __func__);
616             if (!pfl->ro) {
617                 memset(pfl->storage, 0xff, pfl->chip_len);
618                 pflash_update(pfl, 0, pfl->chip_len);
619             }
620             set_dq7(pfl, 0x00);
621             /* Wait the time specified at CFI address 0x22. */
622             timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
623                       (1ULL << pfl->cfi_table[0x22]) * SCALE_MS);
624             break;
625         case 0x30: /* Sector erase */
626             pflash_sector_erase(pfl, offset);
627             break;
628         default:
629             DPRINTF("%s: invalid command %02x (wc 5)\n", __func__, cmd);
630             goto reset_flash;
631         }
632         pfl->cmd = cmd;
633         break;
634     case 6:
635         switch (pfl->cmd) {
636         case 0x10: /* Chip Erase */
637             /* Ignore writes during chip erase */
638             return;
639         case 0x30: /* Sector erase */
640             if (cmd == 0xB0) {
641                 /*
642                  * If erase suspend happens during the erase timeout (so DQ3 is
643                  * 0), then the device suspends erasing immediately. Set the
644                  * remaining time to be the total time to erase. Otherwise,
645                  * there is a maximum amount of time it can take to enter
646                  * suspend mode. Let's ignore that and suspend immediately and
647                  * set the remaining time to the actual time remaining on the
648                  * timer.
649                  */
650                 if ((pfl->status & 0x08) == 0) {
651                     pfl->erase_time_remaining = pflash_erase_time(pfl);
652                 } else {
653                     int64_t delta = timer_expire_time_ns(&pfl->timer) -
654                         qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
655                     /* Make sure we have a positive time remaining. */
656                     pfl->erase_time_remaining = delta <= 0 ? 1 : delta;
657                 }
658                 reset_dq3(pfl);
659                 timer_del(&pfl->timer);
660                 pfl->wcycle = 0;
661                 pfl->cmd = 0;
662                 return;
663             }
664             /*
665              * If DQ3 is 0, additional sector erase commands can be
666              * written and anything else (other than an erase suspend) resets
667              * the device.
668              */
669             if ((pfl->status & 0x08) == 0) {
670                 if (cmd == 0x30) {
671                     pflash_sector_erase(pfl, offset);
672                 } else {
673                     goto reset_flash;
674                 }
675             }
676             /* Ignore writes during the actual erase. */
677             return;
678         default:
679             /* Should never happen */
680             DPRINTF("%s: invalid command state %02x (wc 6)\n",
681                     __func__, pfl->cmd);
682             goto reset_flash;
683         }
684         break;
685     /* Special values for CFI queries */
686     case WCYCLE_CFI:
687     case WCYCLE_AUTOSELECT_CFI:
688         DPRINTF("%s: invalid write in CFI query mode\n", __func__);
689         goto reset_flash;
690     default:
691         /* Should never happen */
692         DPRINTF("%s: invalid write state (wc 7)\n",  __func__);
693         goto reset_flash;
694     }
695     pfl->wcycle++;
696 
697     return;
698 
699     /* Reset flash */
700  reset_flash:
701     trace_pflash_reset();
702     pfl->bypass = 0;
703     pfl->wcycle = 0;
704     pfl->cmd = 0;
705     return;
706 
707  do_bypass:
708     pfl->wcycle = 2;
709     pfl->cmd = 0;
710 }
711 
712 static const MemoryRegionOps pflash_cfi02_ops = {
713     .read = pflash_read,
714     .write = pflash_write,
715     .valid.min_access_size = 1,
716     .valid.max_access_size = 4,
717     .endianness = DEVICE_NATIVE_ENDIAN,
718 };
719 
720 static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
721 {
722     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
723     int ret;
724     Error *local_err = NULL;
725 
726     if (pfl->uniform_sector_len == 0 && pfl->sector_len[0] == 0) {
727         error_setg(errp, "attribute \"sector-length\" not specified or zero.");
728         return;
729     }
730     if (pfl->uniform_nb_blocs == 0 && pfl->nb_blocs[0] == 0) {
731         error_setg(errp, "attribute \"num-blocks\" not specified or zero.");
732         return;
733     }
734     if (pfl->name == NULL) {
735         error_setg(errp, "attribute \"name\" not specified.");
736         return;
737     }
738 
739     int nb_regions;
740     pfl->chip_len = 0;
741     pfl->total_sectors = 0;
742     for (nb_regions = 0; nb_regions < PFLASH_MAX_ERASE_REGIONS; ++nb_regions) {
743         if (pfl->nb_blocs[nb_regions] == 0) {
744             break;
745         }
746         pfl->total_sectors += pfl->nb_blocs[nb_regions];
747         uint64_t sector_len_per_device = pfl->sector_len[nb_regions];
748 
749         /*
750          * The size of each flash sector must be a power of 2 and it must be
751          * aligned at the same power of 2.
752          */
753         if (sector_len_per_device & 0xff ||
754             sector_len_per_device >= (1 << 24) ||
755             !is_power_of_2(sector_len_per_device))
756         {
757             error_setg(errp, "unsupported configuration: "
758                        "sector length[%d] per device = %" PRIx64 ".",
759                        nb_regions, sector_len_per_device);
760             return;
761         }
762         if (pfl->chip_len & (sector_len_per_device - 1)) {
763             error_setg(errp, "unsupported configuration: "
764                        "flash region %d not correctly aligned.",
765                        nb_regions);
766             return;
767         }
768 
769         pfl->chip_len += (uint64_t)pfl->sector_len[nb_regions] *
770                           pfl->nb_blocs[nb_regions];
771     }
772 
773     uint64_t uniform_len = (uint64_t)pfl->uniform_nb_blocs *
774                            pfl->uniform_sector_len;
775     if (nb_regions == 0) {
776         nb_regions = 1;
777         pfl->nb_blocs[0] = pfl->uniform_nb_blocs;
778         pfl->sector_len[0] = pfl->uniform_sector_len;
779         pfl->chip_len = uniform_len;
780         pfl->total_sectors = pfl->uniform_nb_blocs;
781     } else if (uniform_len != 0 && uniform_len != pfl->chip_len) {
782         error_setg(errp, "\"num-blocks\"*\"sector-length\" "
783                    "different from \"num-blocks0\"*\'sector-length0\" + ... + "
784                    "\"num-blocks3\"*\"sector-length3\"");
785         return;
786     }
787 
788     memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
789                                   &pflash_cfi02_ops, pfl, pfl->name,
790                                   pfl->chip_len, &local_err);
791     if (local_err) {
792         error_propagate(errp, local_err);
793         return;
794     }
795 
796     pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem);
797 
798     if (pfl->blk) {
799         uint64_t perm;
800         pfl->ro = blk_is_read_only(pfl->blk);
801         perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE);
802         ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp);
803         if (ret < 0) {
804             return;
805         }
806     } else {
807         pfl->ro = 0;
808     }
809 
810     if (pfl->blk) {
811         if (!blk_check_size_and_read_all(pfl->blk, pfl->storage,
812                                          pfl->chip_len, errp)) {
813             vmstate_unregister_ram(&pfl->orig_mem, DEVICE(pfl));
814             return;
815         }
816     }
817 
818     /* Only 11 bits are used in the comparison. */
819     pfl->unlock_addr0 &= 0x7FF;
820     pfl->unlock_addr1 &= 0x7FF;
821 
822     /* Allocate memory for a bitmap for sectors being erased. */
823     pfl->sector_erase_map = bitmap_new(pfl->total_sectors);
824 
825     pflash_setup_mappings(pfl);
826     pfl->rom_mode = 1;
827     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem);
828 
829     timer_init_ns(&pfl->timer, QEMU_CLOCK_VIRTUAL, pflash_timer, pfl);
830     pfl->wcycle = 0;
831     pfl->cmd = 0;
832     pfl->status = 0;
833 
834     /* Hardcoded CFI table (mostly from SG29 Spansion flash) */
835     const uint16_t pri_ofs = 0x40;
836     /* Standard "QRY" string */
837     pfl->cfi_table[0x10] = 'Q';
838     pfl->cfi_table[0x11] = 'R';
839     pfl->cfi_table[0x12] = 'Y';
840     /* Command set (AMD/Fujitsu) */
841     pfl->cfi_table[0x13] = 0x02;
842     pfl->cfi_table[0x14] = 0x00;
843     /* Primary extended table address */
844     pfl->cfi_table[0x15] = pri_ofs;
845     pfl->cfi_table[0x16] = pri_ofs >> 8;
846     /* Alternate command set (none) */
847     pfl->cfi_table[0x17] = 0x00;
848     pfl->cfi_table[0x18] = 0x00;
849     /* Alternate extended table (none) */
850     pfl->cfi_table[0x19] = 0x00;
851     pfl->cfi_table[0x1A] = 0x00;
852     /* Vcc min */
853     pfl->cfi_table[0x1B] = 0x27;
854     /* Vcc max */
855     pfl->cfi_table[0x1C] = 0x36;
856     /* Vpp min (no Vpp pin) */
857     pfl->cfi_table[0x1D] = 0x00;
858     /* Vpp max (no Vpp pin) */
859     pfl->cfi_table[0x1E] = 0x00;
860     /* Timeout per single byte/word write (128 ms) */
861     pfl->cfi_table[0x1F] = 0x07;
862     /* Timeout for min size buffer write (NA) */
863     pfl->cfi_table[0x20] = 0x00;
864     /* Typical timeout for block erase (512 ms) */
865     pfl->cfi_table[0x21] = 0x09;
866     /* Typical timeout for full chip erase (4096 ms) */
867     pfl->cfi_table[0x22] = 0x0C;
868     /* Reserved */
869     pfl->cfi_table[0x23] = 0x01;
870     /* Max timeout for buffer write (NA) */
871     pfl->cfi_table[0x24] = 0x00;
872     /* Max timeout for block erase */
873     pfl->cfi_table[0x25] = 0x0A;
874     /* Max timeout for chip erase */
875     pfl->cfi_table[0x26] = 0x0D;
876     /* Device size */
877     pfl->cfi_table[0x27] = ctz32(pfl->chip_len);
878     /* Flash device interface (8 & 16 bits) */
879     pfl->cfi_table[0x28] = 0x02;
880     pfl->cfi_table[0x29] = 0x00;
881     /* Max number of bytes in multi-bytes write */
882     /* XXX: disable buffered write as it's not supported */
883     //    pfl->cfi_table[0x2A] = 0x05;
884     pfl->cfi_table[0x2A] = 0x00;
885     pfl->cfi_table[0x2B] = 0x00;
886     /* Number of erase block regions */
887     pfl->cfi_table[0x2c] = nb_regions;
888     /* Erase block regions */
889     for (int i = 0; i < nb_regions; ++i) {
890         uint32_t sector_len_per_device = pfl->sector_len[i];
891         pfl->cfi_table[0x2d + 4 * i] = pfl->nb_blocs[i] - 1;
892         pfl->cfi_table[0x2e + 4 * i] = (pfl->nb_blocs[i] - 1) >> 8;
893         pfl->cfi_table[0x2f + 4 * i] = sector_len_per_device >> 8;
894         pfl->cfi_table[0x30 + 4 * i] = sector_len_per_device >> 16;
895     }
896     assert(0x2c + 4 * nb_regions < pri_ofs);
897 
898     /* Extended */
899     pfl->cfi_table[0x00 + pri_ofs] = 'P';
900     pfl->cfi_table[0x01 + pri_ofs] = 'R';
901     pfl->cfi_table[0x02 + pri_ofs] = 'I';
902 
903     /* Extended version 1.0 */
904     pfl->cfi_table[0x03 + pri_ofs] = '1';
905     pfl->cfi_table[0x04 + pri_ofs] = '0';
906 
907     /* Address sensitive unlock required. */
908     pfl->cfi_table[0x05 + pri_ofs] = 0x00;
909     /* Erase suspend to read/write. */
910     pfl->cfi_table[0x06 + pri_ofs] = 0x02;
911     /* Sector protect not supported. */
912     pfl->cfi_table[0x07 + pri_ofs] = 0x00;
913     /* Temporary sector unprotect not supported. */
914     pfl->cfi_table[0x08 + pri_ofs] = 0x00;
915 
916     /* Sector protect/unprotect scheme. */
917     pfl->cfi_table[0x09 + pri_ofs] = 0x00;
918 
919     /* Simultaneous operation not supported. */
920     pfl->cfi_table[0x0a + pri_ofs] = 0x00;
921     /* Burst mode not supported. */
922     pfl->cfi_table[0x0b + pri_ofs] = 0x00;
923     /* Page mode not supported. */
924     pfl->cfi_table[0x0c + pri_ofs] = 0x00;
925     assert(0x0c + pri_ofs < ARRAY_SIZE(pfl->cfi_table));
926 }
927 
928 static Property pflash_cfi02_properties[] = {
929     DEFINE_PROP_DRIVE("drive", PFlashCFI02, blk),
930     DEFINE_PROP_UINT32("num-blocks", PFlashCFI02, uniform_nb_blocs, 0),
931     DEFINE_PROP_UINT32("sector-length", PFlashCFI02, uniform_sector_len, 0),
932     DEFINE_PROP_UINT32("num-blocks0", PFlashCFI02, nb_blocs[0], 0),
933     DEFINE_PROP_UINT32("sector-length0", PFlashCFI02, sector_len[0], 0),
934     DEFINE_PROP_UINT32("num-blocks1", PFlashCFI02, nb_blocs[1], 0),
935     DEFINE_PROP_UINT32("sector-length1", PFlashCFI02, sector_len[1], 0),
936     DEFINE_PROP_UINT32("num-blocks2", PFlashCFI02, nb_blocs[2], 0),
937     DEFINE_PROP_UINT32("sector-length2", PFlashCFI02, sector_len[2], 0),
938     DEFINE_PROP_UINT32("num-blocks3", PFlashCFI02, nb_blocs[3], 0),
939     DEFINE_PROP_UINT32("sector-length3", PFlashCFI02, sector_len[3], 0),
940     DEFINE_PROP_UINT8("width", PFlashCFI02, width, 0),
941     DEFINE_PROP_UINT8("mappings", PFlashCFI02, mappings, 0),
942     DEFINE_PROP_UINT8("big-endian", PFlashCFI02, be, 0),
943     DEFINE_PROP_UINT16("id0", PFlashCFI02, ident0, 0),
944     DEFINE_PROP_UINT16("id1", PFlashCFI02, ident1, 0),
945     DEFINE_PROP_UINT16("id2", PFlashCFI02, ident2, 0),
946     DEFINE_PROP_UINT16("id3", PFlashCFI02, ident3, 0),
947     DEFINE_PROP_UINT16("unlock-addr0", PFlashCFI02, unlock_addr0, 0),
948     DEFINE_PROP_UINT16("unlock-addr1", PFlashCFI02, unlock_addr1, 0),
949     DEFINE_PROP_STRING("name", PFlashCFI02, name),
950     DEFINE_PROP_END_OF_LIST(),
951 };
952 
953 static void pflash_cfi02_unrealize(DeviceState *dev, Error **errp)
954 {
955     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
956     timer_del(&pfl->timer);
957     g_free(pfl->sector_erase_map);
958 }
959 
960 static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
961 {
962     DeviceClass *dc = DEVICE_CLASS(klass);
963 
964     dc->realize = pflash_cfi02_realize;
965     dc->unrealize = pflash_cfi02_unrealize;
966     device_class_set_props(dc, pflash_cfi02_properties);
967     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
968 }
969 
970 static const TypeInfo pflash_cfi02_info = {
971     .name           = TYPE_PFLASH_CFI02,
972     .parent         = TYPE_SYS_BUS_DEVICE,
973     .instance_size  = sizeof(PFlashCFI02),
974     .class_init     = pflash_cfi02_class_init,
975 };
976 
977 static void pflash_cfi02_register_types(void)
978 {
979     type_register_static(&pflash_cfi02_info);
980 }
981 
982 type_init(pflash_cfi02_register_types)
983 
984 PFlashCFI02 *pflash_cfi02_register(hwaddr base,
985                                    const char *name,
986                                    hwaddr size,
987                                    BlockBackend *blk,
988                                    uint32_t sector_len,
989                                    int nb_mappings, int width,
990                                    uint16_t id0, uint16_t id1,
991                                    uint16_t id2, uint16_t id3,
992                                    uint16_t unlock_addr0,
993                                    uint16_t unlock_addr1,
994                                    int be)
995 {
996     DeviceState *dev = qdev_create(NULL, TYPE_PFLASH_CFI02);
997 
998     if (blk) {
999         qdev_prop_set_drive(dev, "drive", blk, &error_abort);
1000     }
1001     assert(size % sector_len == 0);
1002     qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
1003     qdev_prop_set_uint32(dev, "sector-length", sector_len);
1004     qdev_prop_set_uint8(dev, "width", width);
1005     qdev_prop_set_uint8(dev, "mappings", nb_mappings);
1006     qdev_prop_set_uint8(dev, "big-endian", !!be);
1007     qdev_prop_set_uint16(dev, "id0", id0);
1008     qdev_prop_set_uint16(dev, "id1", id1);
1009     qdev_prop_set_uint16(dev, "id2", id2);
1010     qdev_prop_set_uint16(dev, "id3", id3);
1011     qdev_prop_set_uint16(dev, "unlock-addr0", unlock_addr0);
1012     qdev_prop_set_uint16(dev, "unlock-addr1", unlock_addr1);
1013     qdev_prop_set_string(dev, "name", name);
1014     qdev_init_nofail(dev);
1015 
1016     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
1017     return PFLASH_CFI02(dev);
1018 }
1019