xref: /openbmc/qemu/hw/block/pflash_cfi02.c (revision 7acafcfa)
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/error-report.h"
41 #include "qemu/bitmap.h"
42 #include "qemu/timer.h"
43 #include "sysemu/block-backend.h"
44 #include "qemu/host-utils.h"
45 #include "qemu/module.h"
46 #include "hw/sysbus.h"
47 #include "migration/vmstate.h"
48 #include "trace.h"
49 
50 #define PFLASH_DEBUG false
51 #define DPRINTF(fmt, ...)                                  \
52 do {                                                       \
53     if (PFLASH_DEBUG) {                                    \
54         fprintf(stderr, "PFLASH: " fmt, ## __VA_ARGS__);   \
55     }                                                      \
56 } while (0)
57 
58 #define PFLASH_LAZY_ROMD_THRESHOLD 42
59 
60 /*
61  * The size of the cfi_table indirectly depends on this and the start of the
62  * PRI table directly depends on it. 4 is the maximum size (and also what
63  * seems common) without changing the PRT table address.
64  */
65 #define PFLASH_MAX_ERASE_REGIONS 4
66 
67 /* Special write cycles for CFI queries. */
68 enum {
69     WCYCLE_CFI              = 7,
70     WCYCLE_AUTOSELECT_CFI   = 8,
71 };
72 
73 struct PFlashCFI02 {
74     /*< private >*/
75     SysBusDevice parent_obj;
76     /*< public >*/
77 
78     BlockBackend *blk;
79     uint32_t uniform_nb_blocs;
80     uint32_t uniform_sector_len;
81     uint32_t total_sectors;
82     uint32_t nb_blocs[PFLASH_MAX_ERASE_REGIONS];
83     uint32_t sector_len[PFLASH_MAX_ERASE_REGIONS];
84     uint32_t chip_len;
85     uint8_t mappings;
86     uint8_t width;
87     uint8_t be;
88     int wcycle; /* if 0, the flash is read normally */
89     int bypass;
90     int ro;
91     uint8_t cmd;
92     uint8_t status;
93     /* FIXME: implement array device properties */
94     uint16_t ident0;
95     uint16_t ident1;
96     uint16_t ident2;
97     uint16_t ident3;
98     uint16_t unlock_addr0;
99     uint16_t unlock_addr1;
100     uint8_t cfi_table[0x4d];
101     QEMUTimer timer;
102     /* The device replicates the flash memory across its memory space.  Emulate
103      * that by having a container (.mem) filled with an array of aliases
104      * (.mem_mappings) pointing to the flash memory (.orig_mem).
105      */
106     MemoryRegion mem;
107     MemoryRegion *mem_mappings;    /* array; one per mapping */
108     MemoryRegion orig_mem;
109     int rom_mode;
110     int read_counter; /* used for lazy switch-back to rom mode */
111     int sectors_to_erase;
112     uint64_t erase_time_remaining;
113     unsigned long *sector_erase_map;
114     char *name;
115     void *storage;
116 };
117 
118 /*
119  * Toggle status bit DQ7.
120  */
121 static inline void toggle_dq7(PFlashCFI02 *pfl)
122 {
123     pfl->status ^= 0x80;
124 }
125 
126 /*
127  * Set status bit DQ7 to bit 7 of value.
128  */
129 static inline void set_dq7(PFlashCFI02 *pfl, uint8_t value)
130 {
131     pfl->status &= 0x7F;
132     pfl->status |= value & 0x80;
133 }
134 
135 /*
136  * Toggle status bit DQ6.
137  */
138 static inline void toggle_dq6(PFlashCFI02 *pfl)
139 {
140     pfl->status ^= 0x40;
141 }
142 
143 /*
144  * Turn on DQ3.
145  */
146 static inline void assert_dq3(PFlashCFI02 *pfl)
147 {
148     pfl->status |= 0x08;
149 }
150 
151 /*
152  * Turn off DQ3.
153  */
154 static inline void reset_dq3(PFlashCFI02 *pfl)
155 {
156     pfl->status &= ~0x08;
157 }
158 
159 /*
160  * Toggle status bit DQ2.
161  */
162 static inline void toggle_dq2(PFlashCFI02 *pfl)
163 {
164     pfl->status ^= 0x04;
165 }
166 
167 /*
168  * Set up replicated mappings of the same region.
169  */
170 static void pflash_setup_mappings(PFlashCFI02 *pfl)
171 {
172     unsigned i;
173     hwaddr size = memory_region_size(&pfl->orig_mem);
174 
175     memory_region_init(&pfl->mem, OBJECT(pfl), "pflash", pfl->mappings * size);
176     pfl->mem_mappings = g_new(MemoryRegion, pfl->mappings);
177     for (i = 0; i < pfl->mappings; ++i) {
178         memory_region_init_alias(&pfl->mem_mappings[i], OBJECT(pfl),
179                                  "pflash-alias", &pfl->orig_mem, 0, size);
180         memory_region_add_subregion(&pfl->mem, i * size, &pfl->mem_mappings[i]);
181     }
182 }
183 
184 static void pflash_register_memory(PFlashCFI02 *pfl, int rom_mode)
185 {
186     memory_region_rom_device_set_romd(&pfl->orig_mem, rom_mode);
187     pfl->rom_mode = rom_mode;
188 }
189 
190 static size_t pflash_regions_count(PFlashCFI02 *pfl)
191 {
192     return pfl->cfi_table[0x2c];
193 }
194 
195 /*
196  * Returns the time it takes to erase the number of sectors scheduled for
197  * erasure based on CFI address 0x21 which is "Typical timeout per individual
198  * block erase 2^N ms."
199  */
200 static uint64_t pflash_erase_time(PFlashCFI02 *pfl)
201 {
202     /*
203      * If there are no sectors to erase (which can happen if all of the sectors
204      * to be erased are protected), then erase takes 100 us. Protected sectors
205      * aren't supported so this should never happen.
206      */
207     return ((1ULL << pfl->cfi_table[0x21]) * pfl->sectors_to_erase) * SCALE_US;
208 }
209 
210 /*
211  * Returns true if the device is currently in erase suspend mode.
212  */
213 static inline bool pflash_erase_suspend_mode(PFlashCFI02 *pfl)
214 {
215     return pfl->erase_time_remaining > 0;
216 }
217 
218 static void pflash_timer(void *opaque)
219 {
220     PFlashCFI02 *pfl = opaque;
221 
222     trace_pflash_timer_expired(pfl->cmd);
223     if (pfl->cmd == 0x30) {
224         /*
225          * Sector erase. If DQ3 is 0 when the timer expires, then the 50
226          * us erase timeout has expired so we need to start the timer for the
227          * sector erase algorithm. Otherwise, the erase completed and we should
228          * go back to read array mode.
229          */
230         if ((pfl->status & 0x08) == 0) {
231             assert_dq3(pfl);
232             uint64_t timeout = pflash_erase_time(pfl);
233             timer_mod(&pfl->timer,
234                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
235             DPRINTF("%s: erase timeout fired; erasing %d sectors\n",
236                     __func__, pfl->sectors_to_erase);
237             return;
238         }
239         DPRINTF("%s: sector erase complete\n", __func__);
240         bitmap_zero(pfl->sector_erase_map, pfl->total_sectors);
241         pfl->sectors_to_erase = 0;
242         reset_dq3(pfl);
243     }
244 
245     /* Reset flash */
246     toggle_dq7(pfl);
247     if (pfl->bypass) {
248         pfl->wcycle = 2;
249     } else {
250         pflash_register_memory(pfl, 1);
251         pfl->wcycle = 0;
252     }
253     pfl->cmd = 0;
254 }
255 
256 /*
257  * Read data from flash.
258  */
259 static uint64_t pflash_data_read(PFlashCFI02 *pfl, hwaddr offset,
260                                  unsigned int width)
261 {
262     uint8_t *p = (uint8_t *)pfl->storage + offset;
263     uint64_t ret = pfl->be ? ldn_be_p(p, width) : ldn_le_p(p, width);
264     trace_pflash_data_read(offset, width, ret);
265     return ret;
266 }
267 
268 typedef struct {
269     uint32_t len;
270     uint32_t num;
271 } SectorInfo;
272 
273 /*
274  * offset should be a byte offset of the QEMU device and _not_ a device
275  * offset.
276  */
277 static SectorInfo pflash_sector_info(PFlashCFI02 *pfl, hwaddr offset)
278 {
279     assert(offset < pfl->chip_len);
280     hwaddr addr = 0;
281     uint32_t sector_num = 0;
282     for (int i = 0; i < pflash_regions_count(pfl); ++i) {
283         uint64_t region_size = (uint64_t)pfl->nb_blocs[i] * pfl->sector_len[i];
284         if (addr <= offset && offset < addr + region_size) {
285             return (SectorInfo) {
286                 .len = pfl->sector_len[i],
287                 .num = sector_num + (offset - addr) / pfl->sector_len[i],
288             };
289         }
290         sector_num += pfl->nb_blocs[i];
291         addr += region_size;
292     }
293     abort();
294 }
295 
296 /*
297  * Returns true if the offset refers to a flash sector that is currently being
298  * erased.
299  */
300 static bool pflash_sector_is_erasing(PFlashCFI02 *pfl, hwaddr offset)
301 {
302     long sector_num = pflash_sector_info(pfl, offset).num;
303     return test_bit(sector_num, pfl->sector_erase_map);
304 }
305 
306 static uint64_t pflash_read(void *opaque, hwaddr offset, unsigned int width)
307 {
308     PFlashCFI02 *pfl = opaque;
309     hwaddr boff;
310     uint64_t ret;
311 
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     int ret;
398     if (pfl->blk) {
399         offset_end = offset + size;
400         /* widen to sector boundaries */
401         offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
402         offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
403         ret = blk_pwrite(pfl->blk, offset, pfl->storage + offset,
404                    offset_end - offset, 0);
405         if (ret < 0) {
406             /* TODO set error bit in status */
407             error_report("Could not update PFLASH: %s", strerror(-ret));
408         }
409     }
410 }
411 
412 static void pflash_sector_erase(PFlashCFI02 *pfl, hwaddr offset)
413 {
414     SectorInfo sector_info = pflash_sector_info(pfl, offset);
415     uint64_t sector_len = sector_info.len;
416     offset &= ~(sector_len - 1);
417     DPRINTF("%s: start sector erase at %0*" PRIx64 "-%0*" PRIx64 "\n",
418             __func__, pfl->width * 2, offset,
419             pfl->width * 2, offset + sector_len - 1);
420     if (!pfl->ro) {
421         uint8_t *p = pfl->storage;
422         memset(p + offset, 0xff, sector_len);
423         pflash_update(pfl, offset, sector_len);
424     }
425     set_dq7(pfl, 0x00);
426     ++pfl->sectors_to_erase;
427     set_bit(sector_info.num, pfl->sector_erase_map);
428     /* Set (or reset) the 50 us timer for additional erase commands.  */
429     timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 50000);
430 }
431 
432 static void pflash_write(void *opaque, hwaddr offset, uint64_t value,
433                          unsigned int width)
434 {
435     PFlashCFI02 *pfl = opaque;
436     hwaddr boff;
437     uint8_t *p;
438     uint8_t cmd;
439 
440     trace_pflash_io_write(offset, width, value, pfl->wcycle);
441     cmd = value;
442     if (pfl->cmd != 0xA0) {
443         /* Reset does nothing during chip erase and sector erase. */
444         if (cmd == 0xF0 && pfl->cmd != 0x10 && pfl->cmd != 0x30) {
445             if (pfl->wcycle == WCYCLE_AUTOSELECT_CFI) {
446                 /* Return to autoselect mode. */
447                 pfl->wcycle = 3;
448                 pfl->cmd = 0x90;
449                 return;
450             }
451             goto reset_flash;
452         }
453     }
454     offset &= pfl->chip_len - 1;
455 
456     boff = offset;
457     if (pfl->width == 2) {
458         boff = boff >> 1;
459     } else if (pfl->width == 4) {
460         boff = boff >> 2;
461     }
462     /* Only the least-significant 11 bits are used in most cases. */
463     boff &= 0x7FF;
464     switch (pfl->wcycle) {
465     case 0:
466         /* Set the device in I/O access mode if required */
467         if (pfl->rom_mode)
468             pflash_register_memory(pfl, 0);
469         pfl->read_counter = 0;
470         /* We're in read mode */
471     check_unlock0:
472         if (boff == 0x55 && cmd == 0x98) {
473             /* Enter CFI query mode */
474             pfl->wcycle = WCYCLE_CFI;
475             pfl->cmd = 0x98;
476             return;
477         }
478         /* Handle erase resume in erase suspend mode, otherwise reset. */
479         if (cmd == 0x30) { /* Erase Resume */
480             if (pflash_erase_suspend_mode(pfl)) {
481                 /* Resume the erase. */
482                 timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
483                           pfl->erase_time_remaining);
484                 pfl->erase_time_remaining = 0;
485                 pfl->wcycle = 6;
486                 pfl->cmd = 0x30;
487                 set_dq7(pfl, 0x00);
488                 assert_dq3(pfl);
489                 return;
490             }
491             goto reset_flash;
492         }
493         /* Ignore erase suspend. */
494         if (cmd == 0xB0) { /* Erase Suspend */
495             return;
496         }
497         if (boff != pfl->unlock_addr0 || cmd != 0xAA) {
498             DPRINTF("%s: unlock0 failed " TARGET_FMT_plx " %02x %04x\n",
499                     __func__, boff, cmd, pfl->unlock_addr0);
500             goto reset_flash;
501         }
502         DPRINTF("%s: unlock sequence started\n", __func__);
503         break;
504     case 1:
505         /* We started an unlock sequence */
506     check_unlock1:
507         if (boff != pfl->unlock_addr1 || cmd != 0x55) {
508             DPRINTF("%s: unlock1 failed " TARGET_FMT_plx " %02x\n", __func__,
509                     boff, cmd);
510             goto reset_flash;
511         }
512         DPRINTF("%s: unlock sequence done\n", __func__);
513         break;
514     case 2:
515         /* We finished an unlock sequence */
516         if (!pfl->bypass && boff != pfl->unlock_addr0) {
517             DPRINTF("%s: command failed " TARGET_FMT_plx " %02x\n", __func__,
518                     boff, cmd);
519             goto reset_flash;
520         }
521         switch (cmd) {
522         case 0x20:
523             pfl->bypass = 1;
524             goto do_bypass;
525         case 0x80: /* Erase */
526         case 0x90: /* Autoselect */
527         case 0xA0: /* Program */
528             pfl->cmd = cmd;
529             DPRINTF("%s: starting command %02x\n", __func__, cmd);
530             break;
531         default:
532             DPRINTF("%s: unknown command %02x\n", __func__, cmd);
533             goto reset_flash;
534         }
535         break;
536     case 3:
537         switch (pfl->cmd) {
538         case 0x80: /* Erase */
539             /* We need another unlock sequence */
540             goto check_unlock0;
541         case 0xA0: /* Program */
542             if (pflash_erase_suspend_mode(pfl) &&
543                 pflash_sector_is_erasing(pfl, offset)) {
544                 /* Ignore writes to erasing sectors. */
545                 if (pfl->bypass) {
546                     goto do_bypass;
547                 }
548                 goto reset_flash;
549             }
550             trace_pflash_data_write(offset, width, value, 0);
551             if (!pfl->ro) {
552                 p = (uint8_t *)pfl->storage + offset;
553                 if (pfl->be) {
554                     uint64_t current = ldn_be_p(p, width);
555                     stn_be_p(p, width, current & value);
556                 } else {
557                     uint64_t current = ldn_le_p(p, width);
558                     stn_le_p(p, width, current & value);
559                 }
560                 pflash_update(pfl, offset, width);
561             }
562             /*
563              * While programming, status bit DQ7 should hold the opposite
564              * value from how it was programmed.
565              */
566             set_dq7(pfl, ~value);
567             /* Let's pretend write is immediate */
568             if (pfl->bypass)
569                 goto do_bypass;
570             goto reset_flash;
571         case 0x90: /* Autoselect */
572             if (pfl->bypass && cmd == 0x00) {
573                 /* Unlock bypass reset */
574                 goto reset_flash;
575             }
576             /*
577              * We can enter CFI query mode from autoselect mode, but we must
578              * return to autoselect mode after a reset.
579              */
580             if (boff == 0x55 && cmd == 0x98) {
581                 /* Enter autoselect CFI query mode */
582                 pfl->wcycle = WCYCLE_AUTOSELECT_CFI;
583                 pfl->cmd = 0x98;
584                 return;
585             }
586             /* fall through */
587         default:
588             DPRINTF("%s: invalid write for command %02x\n",
589                     __func__, pfl->cmd);
590             goto reset_flash;
591         }
592     case 4:
593         switch (pfl->cmd) {
594         case 0xA0: /* Program */
595             /* Ignore writes while flash data write is occurring */
596             /* As we suppose write is immediate, this should never happen */
597             return;
598         case 0x80: /* Erase */
599             goto check_unlock1;
600         default:
601             /* Should never happen */
602             DPRINTF("%s: invalid command state %02x (wc 4)\n",
603                     __func__, pfl->cmd);
604             goto reset_flash;
605         }
606         break;
607     case 5:
608         if (pflash_erase_suspend_mode(pfl)) {
609             /* Erasing is not supported in erase suspend mode. */
610             goto reset_flash;
611         }
612         switch (cmd) {
613         case 0x10: /* Chip Erase */
614             if (boff != pfl->unlock_addr0) {
615                 DPRINTF("%s: chip erase: invalid address " TARGET_FMT_plx "\n",
616                         __func__, offset);
617                 goto reset_flash;
618             }
619             /* Chip erase */
620             DPRINTF("%s: start chip erase\n", __func__);
621             if (!pfl->ro) {
622                 memset(pfl->storage, 0xff, pfl->chip_len);
623                 pflash_update(pfl, 0, pfl->chip_len);
624             }
625             set_dq7(pfl, 0x00);
626             /* Wait the time specified at CFI address 0x22. */
627             timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
628                       (1ULL << pfl->cfi_table[0x22]) * SCALE_MS);
629             break;
630         case 0x30: /* Sector erase */
631             pflash_sector_erase(pfl, offset);
632             break;
633         default:
634             DPRINTF("%s: invalid command %02x (wc 5)\n", __func__, cmd);
635             goto reset_flash;
636         }
637         pfl->cmd = cmd;
638         break;
639     case 6:
640         switch (pfl->cmd) {
641         case 0x10: /* Chip Erase */
642             /* Ignore writes during chip erase */
643             return;
644         case 0x30: /* Sector erase */
645             if (cmd == 0xB0) {
646                 /*
647                  * If erase suspend happens during the erase timeout (so DQ3 is
648                  * 0), then the device suspends erasing immediately. Set the
649                  * remaining time to be the total time to erase. Otherwise,
650                  * there is a maximum amount of time it can take to enter
651                  * suspend mode. Let's ignore that and suspend immediately and
652                  * set the remaining time to the actual time remaining on the
653                  * timer.
654                  */
655                 if ((pfl->status & 0x08) == 0) {
656                     pfl->erase_time_remaining = pflash_erase_time(pfl);
657                 } else {
658                     int64_t delta = timer_expire_time_ns(&pfl->timer) -
659                         qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
660                     /* Make sure we have a positive time remaining. */
661                     pfl->erase_time_remaining = delta <= 0 ? 1 : delta;
662                 }
663                 reset_dq3(pfl);
664                 timer_del(&pfl->timer);
665                 pfl->wcycle = 0;
666                 pfl->cmd = 0;
667                 return;
668             }
669             /*
670              * If DQ3 is 0, additional sector erase commands can be
671              * written and anything else (other than an erase suspend) resets
672              * the device.
673              */
674             if ((pfl->status & 0x08) == 0) {
675                 if (cmd == 0x30) {
676                     pflash_sector_erase(pfl, offset);
677                 } else {
678                     goto reset_flash;
679                 }
680             }
681             /* Ignore writes during the actual erase. */
682             return;
683         default:
684             /* Should never happen */
685             DPRINTF("%s: invalid command state %02x (wc 6)\n",
686                     __func__, pfl->cmd);
687             goto reset_flash;
688         }
689         break;
690     /* Special values for CFI queries */
691     case WCYCLE_CFI:
692     case WCYCLE_AUTOSELECT_CFI:
693         DPRINTF("%s: invalid write in CFI query mode\n", __func__);
694         goto reset_flash;
695     default:
696         /* Should never happen */
697         DPRINTF("%s: invalid write state (wc 7)\n",  __func__);
698         goto reset_flash;
699     }
700     pfl->wcycle++;
701 
702     return;
703 
704     /* Reset flash */
705  reset_flash:
706     trace_pflash_reset();
707     pfl->bypass = 0;
708     pfl->wcycle = 0;
709     pfl->cmd = 0;
710     return;
711 
712  do_bypass:
713     pfl->wcycle = 2;
714     pfl->cmd = 0;
715 }
716 
717 static const MemoryRegionOps pflash_cfi02_ops = {
718     .read = pflash_read,
719     .write = pflash_write,
720     .valid.min_access_size = 1,
721     .valid.max_access_size = 4,
722     .endianness = DEVICE_NATIVE_ENDIAN,
723 };
724 
725 static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
726 {
727     ERRP_GUARD();
728     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
729     int ret;
730 
731     if (pfl->uniform_sector_len == 0 && pfl->sector_len[0] == 0) {
732         error_setg(errp, "attribute \"sector-length\" not specified or zero.");
733         return;
734     }
735     if (pfl->uniform_nb_blocs == 0 && pfl->nb_blocs[0] == 0) {
736         error_setg(errp, "attribute \"num-blocks\" not specified or zero.");
737         return;
738     }
739     if (pfl->name == NULL) {
740         error_setg(errp, "attribute \"name\" not specified.");
741         return;
742     }
743 
744     int nb_regions;
745     pfl->chip_len = 0;
746     pfl->total_sectors = 0;
747     for (nb_regions = 0; nb_regions < PFLASH_MAX_ERASE_REGIONS; ++nb_regions) {
748         if (pfl->nb_blocs[nb_regions] == 0) {
749             break;
750         }
751         pfl->total_sectors += pfl->nb_blocs[nb_regions];
752         uint64_t sector_len_per_device = pfl->sector_len[nb_regions];
753 
754         /*
755          * The size of each flash sector must be a power of 2 and it must be
756          * aligned at the same power of 2.
757          */
758         if (sector_len_per_device & 0xff ||
759             sector_len_per_device >= (1 << 24) ||
760             !is_power_of_2(sector_len_per_device))
761         {
762             error_setg(errp, "unsupported configuration: "
763                        "sector length[%d] per device = %" PRIx64 ".",
764                        nb_regions, sector_len_per_device);
765             return;
766         }
767         if (pfl->chip_len & (sector_len_per_device - 1)) {
768             error_setg(errp, "unsupported configuration: "
769                        "flash region %d not correctly aligned.",
770                        nb_regions);
771             return;
772         }
773 
774         pfl->chip_len += (uint64_t)pfl->sector_len[nb_regions] *
775                           pfl->nb_blocs[nb_regions];
776     }
777 
778     uint64_t uniform_len = (uint64_t)pfl->uniform_nb_blocs *
779                            pfl->uniform_sector_len;
780     if (nb_regions == 0) {
781         nb_regions = 1;
782         pfl->nb_blocs[0] = pfl->uniform_nb_blocs;
783         pfl->sector_len[0] = pfl->uniform_sector_len;
784         pfl->chip_len = uniform_len;
785         pfl->total_sectors = pfl->uniform_nb_blocs;
786     } else if (uniform_len != 0 && uniform_len != pfl->chip_len) {
787         error_setg(errp, "\"num-blocks\"*\"sector-length\" "
788                    "different from \"num-blocks0\"*\'sector-length0\" + ... + "
789                    "\"num-blocks3\"*\"sector-length3\"");
790         return;
791     }
792 
793     memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
794                                   &pflash_cfi02_ops, pfl, pfl->name,
795                                   pfl->chip_len, errp);
796     if (*errp) {
797         return;
798     }
799 
800     pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem);
801 
802     if (pfl->blk) {
803         uint64_t perm;
804         pfl->ro = blk_is_read_only(pfl->blk);
805         perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE);
806         ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp);
807         if (ret < 0) {
808             return;
809         }
810     } else {
811         pfl->ro = 0;
812     }
813 
814     if (pfl->blk) {
815         if (!blk_check_size_and_read_all(pfl->blk, pfl->storage,
816                                          pfl->chip_len, errp)) {
817             vmstate_unregister_ram(&pfl->orig_mem, DEVICE(pfl));
818             return;
819         }
820     }
821 
822     /* Only 11 bits are used in the comparison. */
823     pfl->unlock_addr0 &= 0x7FF;
824     pfl->unlock_addr1 &= 0x7FF;
825 
826     /* Allocate memory for a bitmap for sectors being erased. */
827     pfl->sector_erase_map = bitmap_new(pfl->total_sectors);
828 
829     pflash_setup_mappings(pfl);
830     pfl->rom_mode = 1;
831     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem);
832 
833     timer_init_ns(&pfl->timer, QEMU_CLOCK_VIRTUAL, pflash_timer, pfl);
834     pfl->wcycle = 0;
835     pfl->cmd = 0;
836     pfl->status = 0;
837 
838     /* Hardcoded CFI table (mostly from SG29 Spansion flash) */
839     const uint16_t pri_ofs = 0x40;
840     /* Standard "QRY" string */
841     pfl->cfi_table[0x10] = 'Q';
842     pfl->cfi_table[0x11] = 'R';
843     pfl->cfi_table[0x12] = 'Y';
844     /* Command set (AMD/Fujitsu) */
845     pfl->cfi_table[0x13] = 0x02;
846     pfl->cfi_table[0x14] = 0x00;
847     /* Primary extended table address */
848     pfl->cfi_table[0x15] = pri_ofs;
849     pfl->cfi_table[0x16] = pri_ofs >> 8;
850     /* Alternate command set (none) */
851     pfl->cfi_table[0x17] = 0x00;
852     pfl->cfi_table[0x18] = 0x00;
853     /* Alternate extended table (none) */
854     pfl->cfi_table[0x19] = 0x00;
855     pfl->cfi_table[0x1A] = 0x00;
856     /* Vcc min */
857     pfl->cfi_table[0x1B] = 0x27;
858     /* Vcc max */
859     pfl->cfi_table[0x1C] = 0x36;
860     /* Vpp min (no Vpp pin) */
861     pfl->cfi_table[0x1D] = 0x00;
862     /* Vpp max (no Vpp pin) */
863     pfl->cfi_table[0x1E] = 0x00;
864     /* Timeout per single byte/word write (128 ms) */
865     pfl->cfi_table[0x1F] = 0x07;
866     /* Timeout for min size buffer write (NA) */
867     pfl->cfi_table[0x20] = 0x00;
868     /* Typical timeout for block erase (512 ms) */
869     pfl->cfi_table[0x21] = 0x09;
870     /* Typical timeout for full chip erase (4096 ms) */
871     pfl->cfi_table[0x22] = 0x0C;
872     /* Reserved */
873     pfl->cfi_table[0x23] = 0x01;
874     /* Max timeout for buffer write (NA) */
875     pfl->cfi_table[0x24] = 0x00;
876     /* Max timeout for block erase */
877     pfl->cfi_table[0x25] = 0x0A;
878     /* Max timeout for chip erase */
879     pfl->cfi_table[0x26] = 0x0D;
880     /* Device size */
881     pfl->cfi_table[0x27] = ctz32(pfl->chip_len);
882     /* Flash device interface (8 & 16 bits) */
883     pfl->cfi_table[0x28] = 0x02;
884     pfl->cfi_table[0x29] = 0x00;
885     /* Max number of bytes in multi-bytes write */
886     /* XXX: disable buffered write as it's not supported */
887     //    pfl->cfi_table[0x2A] = 0x05;
888     pfl->cfi_table[0x2A] = 0x00;
889     pfl->cfi_table[0x2B] = 0x00;
890     /* Number of erase block regions */
891     pfl->cfi_table[0x2c] = nb_regions;
892     /* Erase block regions */
893     for (int i = 0; i < nb_regions; ++i) {
894         uint32_t sector_len_per_device = pfl->sector_len[i];
895         pfl->cfi_table[0x2d + 4 * i] = pfl->nb_blocs[i] - 1;
896         pfl->cfi_table[0x2e + 4 * i] = (pfl->nb_blocs[i] - 1) >> 8;
897         pfl->cfi_table[0x2f + 4 * i] = sector_len_per_device >> 8;
898         pfl->cfi_table[0x30 + 4 * i] = sector_len_per_device >> 16;
899     }
900     assert(0x2c + 4 * nb_regions < pri_ofs);
901 
902     /* Extended */
903     pfl->cfi_table[0x00 + pri_ofs] = 'P';
904     pfl->cfi_table[0x01 + pri_ofs] = 'R';
905     pfl->cfi_table[0x02 + pri_ofs] = 'I';
906 
907     /* Extended version 1.0 */
908     pfl->cfi_table[0x03 + pri_ofs] = '1';
909     pfl->cfi_table[0x04 + pri_ofs] = '0';
910 
911     /* Address sensitive unlock required. */
912     pfl->cfi_table[0x05 + pri_ofs] = 0x00;
913     /* Erase suspend to read/write. */
914     pfl->cfi_table[0x06 + pri_ofs] = 0x02;
915     /* Sector protect not supported. */
916     pfl->cfi_table[0x07 + pri_ofs] = 0x00;
917     /* Temporary sector unprotect not supported. */
918     pfl->cfi_table[0x08 + pri_ofs] = 0x00;
919 
920     /* Sector protect/unprotect scheme. */
921     pfl->cfi_table[0x09 + pri_ofs] = 0x00;
922 
923     /* Simultaneous operation not supported. */
924     pfl->cfi_table[0x0a + pri_ofs] = 0x00;
925     /* Burst mode not supported. */
926     pfl->cfi_table[0x0b + pri_ofs] = 0x00;
927     /* Page mode not supported. */
928     pfl->cfi_table[0x0c + pri_ofs] = 0x00;
929     assert(0x0c + pri_ofs < ARRAY_SIZE(pfl->cfi_table));
930 }
931 
932 static Property pflash_cfi02_properties[] = {
933     DEFINE_PROP_DRIVE("drive", PFlashCFI02, blk),
934     DEFINE_PROP_UINT32("num-blocks", PFlashCFI02, uniform_nb_blocs, 0),
935     DEFINE_PROP_UINT32("sector-length", PFlashCFI02, uniform_sector_len, 0),
936     DEFINE_PROP_UINT32("num-blocks0", PFlashCFI02, nb_blocs[0], 0),
937     DEFINE_PROP_UINT32("sector-length0", PFlashCFI02, sector_len[0], 0),
938     DEFINE_PROP_UINT32("num-blocks1", PFlashCFI02, nb_blocs[1], 0),
939     DEFINE_PROP_UINT32("sector-length1", PFlashCFI02, sector_len[1], 0),
940     DEFINE_PROP_UINT32("num-blocks2", PFlashCFI02, nb_blocs[2], 0),
941     DEFINE_PROP_UINT32("sector-length2", PFlashCFI02, sector_len[2], 0),
942     DEFINE_PROP_UINT32("num-blocks3", PFlashCFI02, nb_blocs[3], 0),
943     DEFINE_PROP_UINT32("sector-length3", PFlashCFI02, sector_len[3], 0),
944     DEFINE_PROP_UINT8("width", PFlashCFI02, width, 0),
945     DEFINE_PROP_UINT8("mappings", PFlashCFI02, mappings, 0),
946     DEFINE_PROP_UINT8("big-endian", PFlashCFI02, be, 0),
947     DEFINE_PROP_UINT16("id0", PFlashCFI02, ident0, 0),
948     DEFINE_PROP_UINT16("id1", PFlashCFI02, ident1, 0),
949     DEFINE_PROP_UINT16("id2", PFlashCFI02, ident2, 0),
950     DEFINE_PROP_UINT16("id3", PFlashCFI02, ident3, 0),
951     DEFINE_PROP_UINT16("unlock-addr0", PFlashCFI02, unlock_addr0, 0),
952     DEFINE_PROP_UINT16("unlock-addr1", PFlashCFI02, unlock_addr1, 0),
953     DEFINE_PROP_STRING("name", PFlashCFI02, name),
954     DEFINE_PROP_END_OF_LIST(),
955 };
956 
957 static void pflash_cfi02_unrealize(DeviceState *dev)
958 {
959     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
960     timer_del(&pfl->timer);
961     g_free(pfl->sector_erase_map);
962 }
963 
964 static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
965 {
966     DeviceClass *dc = DEVICE_CLASS(klass);
967 
968     dc->realize = pflash_cfi02_realize;
969     dc->unrealize = pflash_cfi02_unrealize;
970     device_class_set_props(dc, pflash_cfi02_properties);
971     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
972 }
973 
974 static const TypeInfo pflash_cfi02_info = {
975     .name           = TYPE_PFLASH_CFI02,
976     .parent         = TYPE_SYS_BUS_DEVICE,
977     .instance_size  = sizeof(PFlashCFI02),
978     .class_init     = pflash_cfi02_class_init,
979 };
980 
981 static void pflash_cfi02_register_types(void)
982 {
983     type_register_static(&pflash_cfi02_info);
984 }
985 
986 type_init(pflash_cfi02_register_types)
987 
988 PFlashCFI02 *pflash_cfi02_register(hwaddr base,
989                                    const char *name,
990                                    hwaddr size,
991                                    BlockBackend *blk,
992                                    uint32_t sector_len,
993                                    int nb_mappings, int width,
994                                    uint16_t id0, uint16_t id1,
995                                    uint16_t id2, uint16_t id3,
996                                    uint16_t unlock_addr0,
997                                    uint16_t unlock_addr1,
998                                    int be)
999 {
1000     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI02);
1001 
1002     if (blk) {
1003         qdev_prop_set_drive(dev, "drive", blk);
1004     }
1005     assert(QEMU_IS_ALIGNED(size, sector_len));
1006     qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
1007     qdev_prop_set_uint32(dev, "sector-length", sector_len);
1008     qdev_prop_set_uint8(dev, "width", width);
1009     qdev_prop_set_uint8(dev, "mappings", nb_mappings);
1010     qdev_prop_set_uint8(dev, "big-endian", !!be);
1011     qdev_prop_set_uint16(dev, "id0", id0);
1012     qdev_prop_set_uint16(dev, "id1", id1);
1013     qdev_prop_set_uint16(dev, "id2", id2);
1014     qdev_prop_set_uint16(dev, "id3", id3);
1015     qdev_prop_set_uint16(dev, "unlock-addr0", unlock_addr0);
1016     qdev_prop_set_uint16(dev, "unlock-addr1", unlock_addr1);
1017     qdev_prop_set_string(dev, "name", name);
1018     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
1019 
1020     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
1021     return PFLASH_CFI02(dev);
1022 }
1023