xref: /qemu/hw/block/pflash_cfi02.c (revision d9106341)
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 2.1 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 "hw/qdev-properties-system.h"
40 #include "qapi/error.h"
41 #include "qemu/error-report.h"
42 #include "qemu/bitmap.h"
43 #include "qemu/timer.h"
44 #include "sysemu/block-backend.h"
45 #include "qemu/host-utils.h"
46 #include "qemu/module.h"
47 #include "hw/sysbus.h"
48 #include "migration/vmstate.h"
49 #include "trace.h"
50 
51 #define PFLASH_DEBUG false
52 #define DPRINTF(fmt, ...)                                  \
53 do {                                                       \
54     if (PFLASH_DEBUG) {                                    \
55         fprintf(stderr, "PFLASH: " fmt, ## __VA_ARGS__);   \
56     }                                                      \
57 } while (0)
58 
59 #define PFLASH_LAZY_ROMD_THRESHOLD 42
60 
61 /*
62  * The size of the cfi_table indirectly depends on this and the start of the
63  * PRI table directly depends on it. 4 is the maximum size (and also what
64  * seems common) without changing the PRT table address.
65  */
66 #define PFLASH_MAX_ERASE_REGIONS 4
67 
68 /* Special write cycles for CFI queries. */
69 enum {
70     WCYCLE_CFI              = 7,
71     WCYCLE_AUTOSELECT_CFI   = 8,
72 };
73 
74 struct PFlashCFI02 {
75     /*< private >*/
76     SysBusDevice parent_obj;
77     /*< public >*/
78 
79     BlockBackend *blk;
80     uint32_t uniform_nb_blocs;
81     uint32_t uniform_sector_len;
82     uint32_t total_sectors;
83     uint32_t nb_blocs[PFLASH_MAX_ERASE_REGIONS];
84     uint32_t sector_len[PFLASH_MAX_ERASE_REGIONS];
85     uint32_t chip_len;
86     uint8_t mappings;
87     uint8_t width;
88     uint8_t be;
89     int wcycle; /* if 0, the flash is read normally */
90     int bypass;
91     int ro;
92     uint8_t cmd;
93     uint8_t status;
94     /* FIXME: implement array device properties */
95     uint16_t ident0;
96     uint16_t ident1;
97     uint16_t ident2;
98     uint16_t ident3;
99     uint16_t unlock_addr0;
100     uint16_t unlock_addr1;
101     uint8_t cfi_table[0x4d];
102     QEMUTimer timer;
103     /*
104      * The device replicates the flash memory across its memory space.  Emulate
105      * that by having a container (.mem) filled with an array of aliases
106      * (.mem_mappings) pointing to the flash memory (.orig_mem).
107      */
108     MemoryRegion mem;
109     MemoryRegion *mem_mappings;    /* array; one per mapping */
110     MemoryRegion orig_mem;
111     bool rom_mode;
112     int read_counter; /* used for lazy switch-back to rom mode */
113     int sectors_to_erase;
114     uint64_t erase_time_remaining;
115     unsigned long *sector_erase_map;
116     char *name;
117     void *storage;
118 };
119 
120 /*
121  * Toggle status bit DQ7.
122  */
123 static inline void toggle_dq7(PFlashCFI02 *pfl)
124 {
125     pfl->status ^= 0x80;
126 }
127 
128 /*
129  * Set status bit DQ7 to bit 7 of value.
130  */
131 static inline void set_dq7(PFlashCFI02 *pfl, uint8_t value)
132 {
133     pfl->status &= 0x7F;
134     pfl->status |= value & 0x80;
135 }
136 
137 /*
138  * Toggle status bit DQ6.
139  */
140 static inline void toggle_dq6(PFlashCFI02 *pfl)
141 {
142     pfl->status ^= 0x40;
143 }
144 
145 /*
146  * Turn on DQ3.
147  */
148 static inline void assert_dq3(PFlashCFI02 *pfl)
149 {
150     pfl->status |= 0x08;
151 }
152 
153 /*
154  * Turn off DQ3.
155  */
156 static inline void reset_dq3(PFlashCFI02 *pfl)
157 {
158     pfl->status &= ~0x08;
159 }
160 
161 /*
162  * Toggle status bit DQ2.
163  */
164 static inline void toggle_dq2(PFlashCFI02 *pfl)
165 {
166     pfl->status ^= 0x04;
167 }
168 
169 /*
170  * Set up replicated mappings of the same region.
171  */
172 static void pflash_setup_mappings(PFlashCFI02 *pfl)
173 {
174     unsigned i;
175     hwaddr size = memory_region_size(&pfl->orig_mem);
176 
177     memory_region_init(&pfl->mem, OBJECT(pfl), "pflash", pfl->mappings * size);
178     pfl->mem_mappings = g_new(MemoryRegion, pfl->mappings);
179     for (i = 0; i < pfl->mappings; ++i) {
180         memory_region_init_alias(&pfl->mem_mappings[i], OBJECT(pfl),
181                                  "pflash-alias", &pfl->orig_mem, 0, size);
182         memory_region_add_subregion(&pfl->mem, i * size, &pfl->mem_mappings[i]);
183     }
184     pfl->rom_mode = true;
185 }
186 
187 static void pflash_reset_state_machine(PFlashCFI02 *pfl)
188 {
189     trace_pflash_reset();
190     pfl->cmd = 0x00;
191     pfl->wcycle = 0;
192 }
193 
194 static void pflash_mode_read_array(PFlashCFI02 *pfl)
195 {
196     trace_pflash_mode_read_array();
197     pflash_reset_state_machine(pfl);
198     pfl->rom_mode = true;
199     memory_region_rom_device_set_romd(&pfl->orig_mem, true);
200 }
201 
202 static size_t pflash_regions_count(PFlashCFI02 *pfl)
203 {
204     return pfl->cfi_table[0x2c];
205 }
206 
207 /*
208  * Returns the time it takes to erase the number of sectors scheduled for
209  * erasure based on CFI address 0x21 which is "Typical timeout per individual
210  * block erase 2^N ms."
211  */
212 static uint64_t pflash_erase_time(PFlashCFI02 *pfl)
213 {
214     /*
215      * If there are no sectors to erase (which can happen if all of the sectors
216      * to be erased are protected), then erase takes 100 us. Protected sectors
217      * aren't supported so this should never happen.
218      */
219     return ((1ULL << pfl->cfi_table[0x21]) * pfl->sectors_to_erase) * SCALE_US;
220 }
221 
222 /*
223  * Returns true if the device is currently in erase suspend mode.
224  */
225 static inline bool pflash_erase_suspend_mode(PFlashCFI02 *pfl)
226 {
227     return pfl->erase_time_remaining > 0;
228 }
229 
230 static void pflash_timer(void *opaque)
231 {
232     PFlashCFI02 *pfl = opaque;
233 
234     trace_pflash_timer_expired(pfl->cmd);
235     if (pfl->cmd == 0x30) {
236         /*
237          * Sector erase. If DQ3 is 0 when the timer expires, then the 50
238          * us erase timeout has expired so we need to start the timer for the
239          * sector erase algorithm. Otherwise, the erase completed and we should
240          * go back to read array mode.
241          */
242         if ((pfl->status & 0x08) == 0) {
243             assert_dq3(pfl);
244             uint64_t timeout = pflash_erase_time(pfl);
245             timer_mod(&pfl->timer,
246                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
247             DPRINTF("%s: erase timeout fired; erasing %d sectors\n",
248                     __func__, pfl->sectors_to_erase);
249             return;
250         }
251         DPRINTF("%s: sector erase complete\n", __func__);
252         bitmap_zero(pfl->sector_erase_map, pfl->total_sectors);
253         pfl->sectors_to_erase = 0;
254         reset_dq3(pfl);
255     }
256 
257     /* Reset flash */
258     toggle_dq7(pfl);
259     if (pfl->bypass) {
260         pfl->wcycle = 2;
261         pfl->cmd = 0;
262     } else {
263         pflash_mode_read_array(pfl);
264     }
265 }
266 
267 /*
268  * Read data from flash.
269  */
270 static uint64_t pflash_data_read(PFlashCFI02 *pfl, hwaddr offset,
271                                  unsigned int width)
272 {
273     uint8_t *p = (uint8_t *)pfl->storage + offset;
274     uint64_t ret = pfl->be ? ldn_be_p(p, width) : ldn_le_p(p, width);
275     trace_pflash_data_read(offset, width, ret);
276     return ret;
277 }
278 
279 typedef struct {
280     uint32_t len;
281     uint32_t num;
282 } SectorInfo;
283 
284 /*
285  * offset should be a byte offset of the QEMU device and _not_ a device
286  * offset.
287  */
288 static SectorInfo pflash_sector_info(PFlashCFI02 *pfl, hwaddr offset)
289 {
290     assert(offset < pfl->chip_len);
291     hwaddr addr = 0;
292     uint32_t sector_num = 0;
293     for (int i = 0; i < pflash_regions_count(pfl); ++i) {
294         uint64_t region_size = (uint64_t)pfl->nb_blocs[i] * pfl->sector_len[i];
295         if (addr <= offset && offset < addr + region_size) {
296             return (SectorInfo) {
297                 .len = pfl->sector_len[i],
298                 .num = sector_num + (offset - addr) / pfl->sector_len[i],
299             };
300         }
301         sector_num += pfl->nb_blocs[i];
302         addr += region_size;
303     }
304     abort();
305 }
306 
307 /*
308  * Returns true if the offset refers to a flash sector that is currently being
309  * erased.
310  */
311 static bool pflash_sector_is_erasing(PFlashCFI02 *pfl, hwaddr offset)
312 {
313     long sector_num = pflash_sector_info(pfl, offset).num;
314     return test_bit(sector_num, pfl->sector_erase_map);
315 }
316 
317 static uint64_t pflash_read(void *opaque, hwaddr offset, unsigned int width)
318 {
319     PFlashCFI02 *pfl = opaque;
320     hwaddr boff;
321     uint64_t ret;
322 
323     /* Lazy reset to ROMD mode after a certain amount of read accesses */
324     if (!pfl->rom_mode && pfl->wcycle == 0 &&
325         ++pfl->read_counter > PFLASH_LAZY_ROMD_THRESHOLD) {
326         pflash_mode_read_array(pfl);
327     }
328     offset &= pfl->chip_len - 1;
329     boff = offset & 0xFF;
330     if (pfl->width == 2) {
331         boff = boff >> 1;
332     } else if (pfl->width == 4) {
333         boff = boff >> 2;
334     }
335     switch (pfl->cmd) {
336     default:
337         /* This should never happen : reset state & treat it as a read*/
338         DPRINTF("%s: unknown command state: %x\n", __func__, pfl->cmd);
339         pflash_reset_state_machine(pfl);
340         /* fall through to the read code */
341     case 0x80: /* Erase (unlock) */
342         /* We accept reads during second unlock sequence... */
343     case 0x00:
344         if (pflash_erase_suspend_mode(pfl) &&
345             pflash_sector_is_erasing(pfl, offset)) {
346             /* Toggle bit 2, but not 6. */
347             toggle_dq2(pfl);
348             /* Status register read */
349             ret = pfl->status;
350             DPRINTF("%s: status %" PRIx64 "\n", __func__, ret);
351             break;
352         }
353         /* Flash area read */
354         ret = pflash_data_read(pfl, offset, width);
355         break;
356     case 0x90: /* flash ID read */
357         switch (boff) {
358         case 0x00:
359         case 0x01:
360             ret = boff & 0x01 ? pfl->ident1 : pfl->ident0;
361             break;
362         case 0x02:
363             ret = 0x00; /* Pretend all sectors are unprotected */
364             break;
365         case 0x0E:
366         case 0x0F:
367             ret = boff & 0x01 ? pfl->ident3 : pfl->ident2;
368             if (ret != (uint8_t)-1) {
369                 break;
370             }
371             /* Fall through to data read. */
372         default:
373             ret = pflash_data_read(pfl, offset, width);
374         }
375         DPRINTF("%s: ID " TARGET_FMT_plx " %" PRIx64 "\n", __func__, boff, ret);
376         break;
377     case 0x10: /* Chip Erase */
378     case 0x30: /* Sector Erase */
379         /* Toggle bit 2 during erase, but not program. */
380         toggle_dq2(pfl);
381         /* fall through */
382     case 0xA0: /* Program */
383         /* Toggle bit 6 */
384         toggle_dq6(pfl);
385         /* Status register read */
386         ret = pfl->status;
387         DPRINTF("%s: status %" PRIx64 "\n", __func__, ret);
388         break;
389     case 0x98:
390         /* CFI query mode */
391         if (boff < sizeof(pfl->cfi_table)) {
392             ret = pfl->cfi_table[boff];
393         } else {
394             ret = 0;
395         }
396         break;
397     }
398     trace_pflash_io_read(offset, width, ret, pfl->cmd, pfl->wcycle);
399 
400     return ret;
401 }
402 
403 /* update flash content on disk */
404 static void pflash_update(PFlashCFI02 *pfl, int offset, int size)
405 {
406     int offset_end;
407     int ret;
408     if (pfl->blk) {
409         offset_end = offset + size;
410         /* widen to sector boundaries */
411         offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
412         offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
413         ret = blk_pwrite(pfl->blk, offset, pfl->storage + offset,
414                    offset_end - offset, 0);
415         if (ret < 0) {
416             /* TODO set error bit in status */
417             error_report("Could not update PFLASH: %s", strerror(-ret));
418         }
419     }
420 }
421 
422 static void pflash_sector_erase(PFlashCFI02 *pfl, hwaddr offset)
423 {
424     SectorInfo sector_info = pflash_sector_info(pfl, offset);
425     uint64_t sector_len = sector_info.len;
426     offset &= ~(sector_len - 1);
427     DPRINTF("%s: start sector erase at %0*" PRIx64 "-%0*" PRIx64 "\n",
428             __func__, pfl->width * 2, offset,
429             pfl->width * 2, offset + sector_len - 1);
430     if (!pfl->ro) {
431         uint8_t *p = pfl->storage;
432         memset(p + offset, 0xff, sector_len);
433         pflash_update(pfl, offset, sector_len);
434     }
435     set_dq7(pfl, 0x00);
436     ++pfl->sectors_to_erase;
437     set_bit(sector_info.num, pfl->sector_erase_map);
438     /* Set (or reset) the 50 us timer for additional erase commands.  */
439     timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 50000);
440 }
441 
442 static void pflash_write(void *opaque, hwaddr offset, uint64_t value,
443                          unsigned int width)
444 {
445     PFlashCFI02 *pfl = opaque;
446     hwaddr boff;
447     uint8_t *p;
448     uint8_t cmd;
449 
450     trace_pflash_io_write(offset, width, value, pfl->wcycle);
451     cmd = value;
452     if (pfl->cmd != 0xA0) {
453         /* Reset does nothing during chip erase and sector erase. */
454         if (cmd == 0xF0 && pfl->cmd != 0x10 && pfl->cmd != 0x30) {
455             if (pfl->wcycle == WCYCLE_AUTOSELECT_CFI) {
456                 /* Return to autoselect mode. */
457                 pfl->wcycle = 3;
458                 pfl->cmd = 0x90;
459                 return;
460             }
461             goto reset_flash;
462         }
463     }
464     offset &= pfl->chip_len - 1;
465 
466     boff = offset;
467     if (pfl->width == 2) {
468         boff = boff >> 1;
469     } else if (pfl->width == 4) {
470         boff = boff >> 2;
471     }
472     /* Only the least-significant 11 bits are used in most cases. */
473     boff &= 0x7FF;
474     switch (pfl->wcycle) {
475     case 0:
476         /* Set the device in I/O access mode if required */
477         if (pfl->rom_mode) {
478             pfl->rom_mode = false;
479             memory_region_rom_device_set_romd(&pfl->orig_mem, false);
480         }
481         pfl->read_counter = 0;
482         /* We're in read mode */
483     check_unlock0:
484         if (boff == 0x55 && cmd == 0x98) {
485             /* Enter CFI query mode */
486             pfl->wcycle = WCYCLE_CFI;
487             pfl->cmd = 0x98;
488             return;
489         }
490         /* Handle erase resume in erase suspend mode, otherwise reset. */
491         if (cmd == 0x30) { /* Erase Resume */
492             if (pflash_erase_suspend_mode(pfl)) {
493                 /* Resume the erase. */
494                 timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
495                           pfl->erase_time_remaining);
496                 pfl->erase_time_remaining = 0;
497                 pfl->wcycle = 6;
498                 pfl->cmd = 0x30;
499                 set_dq7(pfl, 0x00);
500                 assert_dq3(pfl);
501                 return;
502             }
503             goto reset_flash;
504         }
505         /* Ignore erase suspend. */
506         if (cmd == 0xB0) { /* Erase Suspend */
507             return;
508         }
509         if (boff != pfl->unlock_addr0 || cmd != 0xAA) {
510             DPRINTF("%s: unlock0 failed " TARGET_FMT_plx " %02x %04x\n",
511                     __func__, boff, cmd, pfl->unlock_addr0);
512             goto reset_flash;
513         }
514         DPRINTF("%s: unlock sequence started\n", __func__);
515         break;
516     case 1:
517         /* We started an unlock sequence */
518     check_unlock1:
519         if (boff != pfl->unlock_addr1 || cmd != 0x55) {
520             DPRINTF("%s: unlock1 failed " TARGET_FMT_plx " %02x\n", __func__,
521                     boff, cmd);
522             goto reset_flash;
523         }
524         DPRINTF("%s: unlock sequence done\n", __func__);
525         break;
526     case 2:
527         /* We finished an unlock sequence */
528         if (!pfl->bypass && boff != pfl->unlock_addr0) {
529             DPRINTF("%s: command failed " TARGET_FMT_plx " %02x\n", __func__,
530                     boff, cmd);
531             goto reset_flash;
532         }
533         switch (cmd) {
534         case 0x20:
535             pfl->bypass = 1;
536             goto do_bypass;
537         case 0x80: /* Erase */
538         case 0x90: /* Autoselect */
539         case 0xA0: /* Program */
540             pfl->cmd = cmd;
541             DPRINTF("%s: starting command %02x\n", __func__, cmd);
542             break;
543         default:
544             DPRINTF("%s: unknown command %02x\n", __func__, cmd);
545             goto reset_flash;
546         }
547         break;
548     case 3:
549         switch (pfl->cmd) {
550         case 0x80: /* Erase */
551             /* We need another unlock sequence */
552             goto check_unlock0;
553         case 0xA0: /* Program */
554             if (pflash_erase_suspend_mode(pfl) &&
555                 pflash_sector_is_erasing(pfl, offset)) {
556                 /* Ignore writes to erasing sectors. */
557                 if (pfl->bypass) {
558                     goto do_bypass;
559                 }
560                 goto reset_flash;
561             }
562             trace_pflash_data_write(offset, width, value, 0);
563             if (!pfl->ro) {
564                 p = (uint8_t *)pfl->storage + offset;
565                 if (pfl->be) {
566                     uint64_t current = ldn_be_p(p, width);
567                     stn_be_p(p, width, current & value);
568                 } else {
569                     uint64_t current = ldn_le_p(p, width);
570                     stn_le_p(p, width, current & value);
571                 }
572                 pflash_update(pfl, offset, width);
573             }
574             /*
575              * While programming, status bit DQ7 should hold the opposite
576              * value from how it was programmed.
577              */
578             set_dq7(pfl, ~value);
579             /* Let's pretend write is immediate */
580             if (pfl->bypass)
581                 goto do_bypass;
582             goto reset_flash;
583         case 0x90: /* Autoselect */
584             if (pfl->bypass && cmd == 0x00) {
585                 /* Unlock bypass reset */
586                 goto reset_flash;
587             }
588             /*
589              * We can enter CFI query mode from autoselect mode, but we must
590              * return to autoselect mode after a reset.
591              */
592             if (boff == 0x55 && cmd == 0x98) {
593                 /* Enter autoselect CFI query mode */
594                 pfl->wcycle = WCYCLE_AUTOSELECT_CFI;
595                 pfl->cmd = 0x98;
596                 return;
597             }
598             /* fall through */
599         default:
600             DPRINTF("%s: invalid write for command %02x\n",
601                     __func__, pfl->cmd);
602             goto reset_flash;
603         }
604     case 4:
605         switch (pfl->cmd) {
606         case 0xA0: /* Program */
607             /* Ignore writes while flash data write is occurring */
608             /* As we suppose write is immediate, this should never happen */
609             return;
610         case 0x80: /* Erase */
611             goto check_unlock1;
612         default:
613             /* Should never happen */
614             DPRINTF("%s: invalid command state %02x (wc 4)\n",
615                     __func__, pfl->cmd);
616             goto reset_flash;
617         }
618         break;
619     case 5:
620         if (pflash_erase_suspend_mode(pfl)) {
621             /* Erasing is not supported in erase suspend mode. */
622             goto reset_flash;
623         }
624         switch (cmd) {
625         case 0x10: /* Chip Erase */
626             if (boff != pfl->unlock_addr0) {
627                 DPRINTF("%s: chip erase: invalid address " TARGET_FMT_plx "\n",
628                         __func__, offset);
629                 goto reset_flash;
630             }
631             /* Chip erase */
632             DPRINTF("%s: start chip erase\n", __func__);
633             if (!pfl->ro) {
634                 memset(pfl->storage, 0xff, pfl->chip_len);
635                 pflash_update(pfl, 0, pfl->chip_len);
636             }
637             set_dq7(pfl, 0x00);
638             /* Wait the time specified at CFI address 0x22. */
639             timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
640                       (1ULL << pfl->cfi_table[0x22]) * SCALE_MS);
641             break;
642         case 0x30: /* Sector erase */
643             pflash_sector_erase(pfl, offset);
644             break;
645         default:
646             DPRINTF("%s: invalid command %02x (wc 5)\n", __func__, cmd);
647             goto reset_flash;
648         }
649         pfl->cmd = cmd;
650         break;
651     case 6:
652         switch (pfl->cmd) {
653         case 0x10: /* Chip Erase */
654             /* Ignore writes during chip erase */
655             return;
656         case 0x30: /* Sector erase */
657             if (cmd == 0xB0) {
658                 /*
659                  * If erase suspend happens during the erase timeout (so DQ3 is
660                  * 0), then the device suspends erasing immediately. Set the
661                  * remaining time to be the total time to erase. Otherwise,
662                  * there is a maximum amount of time it can take to enter
663                  * suspend mode. Let's ignore that and suspend immediately and
664                  * set the remaining time to the actual time remaining on the
665                  * timer.
666                  */
667                 if ((pfl->status & 0x08) == 0) {
668                     pfl->erase_time_remaining = pflash_erase_time(pfl);
669                 } else {
670                     int64_t delta = timer_expire_time_ns(&pfl->timer) -
671                         qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
672                     /* Make sure we have a positive time remaining. */
673                     pfl->erase_time_remaining = delta <= 0 ? 1 : delta;
674                 }
675                 reset_dq3(pfl);
676                 timer_del(&pfl->timer);
677                 pflash_reset_state_machine(pfl);
678                 return;
679             }
680             /*
681              * If DQ3 is 0, additional sector erase commands can be
682              * written and anything else (other than an erase suspend) resets
683              * the device.
684              */
685             if ((pfl->status & 0x08) == 0) {
686                 if (cmd == 0x30) {
687                     pflash_sector_erase(pfl, offset);
688                 } else {
689                     goto reset_flash;
690                 }
691             }
692             /* Ignore writes during the actual erase. */
693             return;
694         default:
695             /* Should never happen */
696             DPRINTF("%s: invalid command state %02x (wc 6)\n",
697                     __func__, pfl->cmd);
698             goto reset_flash;
699         }
700         break;
701     /* Special values for CFI queries */
702     case WCYCLE_CFI:
703     case WCYCLE_AUTOSELECT_CFI:
704         DPRINTF("%s: invalid write in CFI query mode\n", __func__);
705         goto reset_flash;
706     default:
707         /* Should never happen */
708         DPRINTF("%s: invalid write state (wc 7)\n",  __func__);
709         goto reset_flash;
710     }
711     pfl->wcycle++;
712 
713     return;
714 
715     /* Reset flash */
716  reset_flash:
717     pfl->bypass = 0;
718     pflash_reset_state_machine(pfl);
719     return;
720 
721  do_bypass:
722     pfl->wcycle = 2;
723     pfl->cmd = 0;
724 }
725 
726 static const MemoryRegionOps pflash_cfi02_ops = {
727     .read = pflash_read,
728     .write = pflash_write,
729     .valid.min_access_size = 1,
730     .valid.max_access_size = 4,
731     .endianness = DEVICE_NATIVE_ENDIAN,
732 };
733 
734 static void pflash_cfi02_fill_cfi_table(PFlashCFI02 *pfl, int nb_regions)
735 {
736     /* Hardcoded CFI table (mostly from SG29 Spansion flash) */
737     const uint16_t pri_ofs = 0x40;
738     /* Standard "QRY" string */
739     pfl->cfi_table[0x10] = 'Q';
740     pfl->cfi_table[0x11] = 'R';
741     pfl->cfi_table[0x12] = 'Y';
742     /* Command set (AMD/Fujitsu) */
743     pfl->cfi_table[0x13] = 0x02;
744     pfl->cfi_table[0x14] = 0x00;
745     /* Primary extended table address */
746     pfl->cfi_table[0x15] = pri_ofs;
747     pfl->cfi_table[0x16] = pri_ofs >> 8;
748     /* Alternate command set (none) */
749     pfl->cfi_table[0x17] = 0x00;
750     pfl->cfi_table[0x18] = 0x00;
751     /* Alternate extended table (none) */
752     pfl->cfi_table[0x19] = 0x00;
753     pfl->cfi_table[0x1A] = 0x00;
754     /* Vcc min */
755     pfl->cfi_table[0x1B] = 0x27;
756     /* Vcc max */
757     pfl->cfi_table[0x1C] = 0x36;
758     /* Vpp min (no Vpp pin) */
759     pfl->cfi_table[0x1D] = 0x00;
760     /* Vpp max (no Vpp pin) */
761     pfl->cfi_table[0x1E] = 0x00;
762     /* Timeout per single byte/word write (128 ms) */
763     pfl->cfi_table[0x1F] = 0x07;
764     /* Timeout for min size buffer write (NA) */
765     pfl->cfi_table[0x20] = 0x00;
766     /* Typical timeout for block erase (512 ms) */
767     pfl->cfi_table[0x21] = 0x09;
768     /* Typical timeout for full chip erase (4096 ms) */
769     pfl->cfi_table[0x22] = 0x0C;
770     /* Reserved */
771     pfl->cfi_table[0x23] = 0x01;
772     /* Max timeout for buffer write (NA) */
773     pfl->cfi_table[0x24] = 0x00;
774     /* Max timeout for block erase */
775     pfl->cfi_table[0x25] = 0x0A;
776     /* Max timeout for chip erase */
777     pfl->cfi_table[0x26] = 0x0D;
778     /* Device size */
779     pfl->cfi_table[0x27] = ctz32(pfl->chip_len);
780     /* Flash device interface (8 & 16 bits) */
781     pfl->cfi_table[0x28] = 0x02;
782     pfl->cfi_table[0x29] = 0x00;
783     /* Max number of bytes in multi-bytes write */
784     /*
785      * XXX: disable buffered write as it's not supported
786      * pfl->cfi_table[0x2A] = 0x05;
787      */
788     pfl->cfi_table[0x2A] = 0x00;
789     pfl->cfi_table[0x2B] = 0x00;
790     /* Number of erase block regions */
791     pfl->cfi_table[0x2c] = nb_regions;
792     /* Erase block regions */
793     for (int i = 0; i < nb_regions; ++i) {
794         uint32_t sector_len_per_device = pfl->sector_len[i];
795         pfl->cfi_table[0x2d + 4 * i] = pfl->nb_blocs[i] - 1;
796         pfl->cfi_table[0x2e + 4 * i] = (pfl->nb_blocs[i] - 1) >> 8;
797         pfl->cfi_table[0x2f + 4 * i] = sector_len_per_device >> 8;
798         pfl->cfi_table[0x30 + 4 * i] = sector_len_per_device >> 16;
799     }
800     assert(0x2c + 4 * nb_regions < pri_ofs);
801 
802     /* Extended */
803     pfl->cfi_table[0x00 + pri_ofs] = 'P';
804     pfl->cfi_table[0x01 + pri_ofs] = 'R';
805     pfl->cfi_table[0x02 + pri_ofs] = 'I';
806 
807     /* Extended version 1.0 */
808     pfl->cfi_table[0x03 + pri_ofs] = '1';
809     pfl->cfi_table[0x04 + pri_ofs] = '0';
810 
811     /* Address sensitive unlock required. */
812     pfl->cfi_table[0x05 + pri_ofs] = 0x00;
813     /* Erase suspend to read/write. */
814     pfl->cfi_table[0x06 + pri_ofs] = 0x02;
815     /* Sector protect not supported. */
816     pfl->cfi_table[0x07 + pri_ofs] = 0x00;
817     /* Temporary sector unprotect not supported. */
818     pfl->cfi_table[0x08 + pri_ofs] = 0x00;
819 
820     /* Sector protect/unprotect scheme. */
821     pfl->cfi_table[0x09 + pri_ofs] = 0x00;
822 
823     /* Simultaneous operation not supported. */
824     pfl->cfi_table[0x0a + pri_ofs] = 0x00;
825     /* Burst mode not supported. */
826     pfl->cfi_table[0x0b + pri_ofs] = 0x00;
827     /* Page mode not supported. */
828     pfl->cfi_table[0x0c + pri_ofs] = 0x00;
829     assert(0x0c + pri_ofs < ARRAY_SIZE(pfl->cfi_table));
830 }
831 
832 static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
833 {
834     ERRP_GUARD();
835     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
836     int ret;
837 
838     if (pfl->uniform_sector_len == 0 && pfl->sector_len[0] == 0) {
839         error_setg(errp, "attribute \"sector-length\" not specified or zero.");
840         return;
841     }
842     if (pfl->uniform_nb_blocs == 0 && pfl->nb_blocs[0] == 0) {
843         error_setg(errp, "attribute \"num-blocks\" not specified or zero.");
844         return;
845     }
846     if (pfl->name == NULL) {
847         error_setg(errp, "attribute \"name\" not specified.");
848         return;
849     }
850 
851     int nb_regions;
852     pfl->chip_len = 0;
853     pfl->total_sectors = 0;
854     for (nb_regions = 0; nb_regions < PFLASH_MAX_ERASE_REGIONS; ++nb_regions) {
855         if (pfl->nb_blocs[nb_regions] == 0) {
856             break;
857         }
858         pfl->total_sectors += pfl->nb_blocs[nb_regions];
859         uint64_t sector_len_per_device = pfl->sector_len[nb_regions];
860 
861         /*
862          * The size of each flash sector must be a power of 2 and it must be
863          * aligned at the same power of 2.
864          */
865         if (sector_len_per_device & 0xff ||
866             sector_len_per_device >= (1 << 24) ||
867             !is_power_of_2(sector_len_per_device))
868         {
869             error_setg(errp, "unsupported configuration: "
870                        "sector length[%d] per device = %" PRIx64 ".",
871                        nb_regions, sector_len_per_device);
872             return;
873         }
874         if (pfl->chip_len & (sector_len_per_device - 1)) {
875             error_setg(errp, "unsupported configuration: "
876                        "flash region %d not correctly aligned.",
877                        nb_regions);
878             return;
879         }
880 
881         pfl->chip_len += (uint64_t)pfl->sector_len[nb_regions] *
882                           pfl->nb_blocs[nb_regions];
883     }
884 
885     uint64_t uniform_len = (uint64_t)pfl->uniform_nb_blocs *
886                            pfl->uniform_sector_len;
887     if (nb_regions == 0) {
888         nb_regions = 1;
889         pfl->nb_blocs[0] = pfl->uniform_nb_blocs;
890         pfl->sector_len[0] = pfl->uniform_sector_len;
891         pfl->chip_len = uniform_len;
892         pfl->total_sectors = pfl->uniform_nb_blocs;
893     } else if (uniform_len != 0 && uniform_len != pfl->chip_len) {
894         error_setg(errp, "\"num-blocks\"*\"sector-length\" "
895                    "different from \"num-blocks0\"*\'sector-length0\" + ... + "
896                    "\"num-blocks3\"*\"sector-length3\"");
897         return;
898     }
899 
900     memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
901                                   &pflash_cfi02_ops, pfl, pfl->name,
902                                   pfl->chip_len, errp);
903     if (*errp) {
904         return;
905     }
906 
907     pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem);
908 
909     if (pfl->blk) {
910         uint64_t perm;
911         pfl->ro = !blk_supports_write_perm(pfl->blk);
912         perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE);
913         ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp);
914         if (ret < 0) {
915             return;
916         }
917     } else {
918         pfl->ro = 0;
919     }
920 
921     if (pfl->blk) {
922         if (!blk_check_size_and_read_all(pfl->blk, pfl->storage,
923                                          pfl->chip_len, errp)) {
924             vmstate_unregister_ram(&pfl->orig_mem, DEVICE(pfl));
925             return;
926         }
927     }
928 
929     /* Only 11 bits are used in the comparison. */
930     pfl->unlock_addr0 &= 0x7FF;
931     pfl->unlock_addr1 &= 0x7FF;
932 
933     /* Allocate memory for a bitmap for sectors being erased. */
934     pfl->sector_erase_map = bitmap_new(pfl->total_sectors);
935 
936     pflash_setup_mappings(pfl);
937     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem);
938 
939     timer_init_ns(&pfl->timer, QEMU_CLOCK_VIRTUAL, pflash_timer, pfl);
940     pfl->status = 0;
941 
942     pflash_cfi02_fill_cfi_table(pfl, nb_regions);
943 }
944 
945 static void pflash_cfi02_reset(DeviceState *dev)
946 {
947     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
948 
949     pflash_reset_state_machine(pfl);
950 }
951 
952 static Property pflash_cfi02_properties[] = {
953     DEFINE_PROP_DRIVE("drive", PFlashCFI02, blk),
954     DEFINE_PROP_UINT32("num-blocks", PFlashCFI02, uniform_nb_blocs, 0),
955     DEFINE_PROP_UINT32("sector-length", PFlashCFI02, uniform_sector_len, 0),
956     DEFINE_PROP_UINT32("num-blocks0", PFlashCFI02, nb_blocs[0], 0),
957     DEFINE_PROP_UINT32("sector-length0", PFlashCFI02, sector_len[0], 0),
958     DEFINE_PROP_UINT32("num-blocks1", PFlashCFI02, nb_blocs[1], 0),
959     DEFINE_PROP_UINT32("sector-length1", PFlashCFI02, sector_len[1], 0),
960     DEFINE_PROP_UINT32("num-blocks2", PFlashCFI02, nb_blocs[2], 0),
961     DEFINE_PROP_UINT32("sector-length2", PFlashCFI02, sector_len[2], 0),
962     DEFINE_PROP_UINT32("num-blocks3", PFlashCFI02, nb_blocs[3], 0),
963     DEFINE_PROP_UINT32("sector-length3", PFlashCFI02, sector_len[3], 0),
964     DEFINE_PROP_UINT8("width", PFlashCFI02, width, 0),
965     DEFINE_PROP_UINT8("mappings", PFlashCFI02, mappings, 0),
966     DEFINE_PROP_UINT8("big-endian", PFlashCFI02, be, 0),
967     DEFINE_PROP_UINT16("id0", PFlashCFI02, ident0, 0),
968     DEFINE_PROP_UINT16("id1", PFlashCFI02, ident1, 0),
969     DEFINE_PROP_UINT16("id2", PFlashCFI02, ident2, 0),
970     DEFINE_PROP_UINT16("id3", PFlashCFI02, ident3, 0),
971     DEFINE_PROP_UINT16("unlock-addr0", PFlashCFI02, unlock_addr0, 0),
972     DEFINE_PROP_UINT16("unlock-addr1", PFlashCFI02, unlock_addr1, 0),
973     DEFINE_PROP_STRING("name", PFlashCFI02, name),
974     DEFINE_PROP_END_OF_LIST(),
975 };
976 
977 static void pflash_cfi02_unrealize(DeviceState *dev)
978 {
979     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
980     timer_del(&pfl->timer);
981     g_free(pfl->sector_erase_map);
982 }
983 
984 static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
985 {
986     DeviceClass *dc = DEVICE_CLASS(klass);
987 
988     dc->realize = pflash_cfi02_realize;
989     dc->reset = pflash_cfi02_reset;
990     dc->unrealize = pflash_cfi02_unrealize;
991     device_class_set_props(dc, pflash_cfi02_properties);
992     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
993 }
994 
995 static const TypeInfo pflash_cfi02_info = {
996     .name           = TYPE_PFLASH_CFI02,
997     .parent         = TYPE_SYS_BUS_DEVICE,
998     .instance_size  = sizeof(PFlashCFI02),
999     .class_init     = pflash_cfi02_class_init,
1000 };
1001 
1002 static void pflash_cfi02_register_types(void)
1003 {
1004     type_register_static(&pflash_cfi02_info);
1005 }
1006 
1007 type_init(pflash_cfi02_register_types)
1008 
1009 PFlashCFI02 *pflash_cfi02_register(hwaddr base,
1010                                    const char *name,
1011                                    hwaddr size,
1012                                    BlockBackend *blk,
1013                                    uint32_t sector_len,
1014                                    int nb_mappings, int width,
1015                                    uint16_t id0, uint16_t id1,
1016                                    uint16_t id2, uint16_t id3,
1017                                    uint16_t unlock_addr0,
1018                                    uint16_t unlock_addr1,
1019                                    int be)
1020 {
1021     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI02);
1022 
1023     if (blk) {
1024         qdev_prop_set_drive(dev, "drive", blk);
1025     }
1026     assert(QEMU_IS_ALIGNED(size, sector_len));
1027     qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
1028     qdev_prop_set_uint32(dev, "sector-length", sector_len);
1029     qdev_prop_set_uint8(dev, "width", width);
1030     qdev_prop_set_uint8(dev, "mappings", nb_mappings);
1031     qdev_prop_set_uint8(dev, "big-endian", !!be);
1032     qdev_prop_set_uint16(dev, "id0", id0);
1033     qdev_prop_set_uint16(dev, "id1", id1);
1034     qdev_prop_set_uint16(dev, "id2", id2);
1035     qdev_prop_set_uint16(dev, "id3", id3);
1036     qdev_prop_set_uint16(dev, "unlock-addr0", unlock_addr0);
1037     qdev_prop_set_uint16(dev, "unlock-addr1", unlock_addr1);
1038     qdev_prop_set_string(dev, "name", name);
1039     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
1040 
1041     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
1042     return PFLASH_CFI02(dev);
1043 }
1044