xref: /openbmc/qemu/hw/block/pflash_cfi02.c (revision d177892d)
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_LAZY_ROMD_THRESHOLD 42
52 
53 /*
54  * The size of the cfi_table indirectly depends on this and the start of the
55  * PRI table directly depends on it. 4 is the maximum size (and also what
56  * seems common) without changing the PRT table address.
57  */
58 #define PFLASH_MAX_ERASE_REGIONS 4
59 
60 /* Special write cycles for CFI queries. */
61 enum {
62     WCYCLE_CFI              = 7,
63     WCYCLE_AUTOSELECT_CFI   = 8,
64 };
65 
66 struct PFlashCFI02 {
67     /*< private >*/
68     SysBusDevice parent_obj;
69     /*< public >*/
70 
71     BlockBackend *blk;
72     uint32_t uniform_nb_blocs;
73     uint32_t uniform_sector_len;
74     uint32_t total_sectors;
75     uint32_t nb_blocs[PFLASH_MAX_ERASE_REGIONS];
76     uint32_t sector_len[PFLASH_MAX_ERASE_REGIONS];
77     uint32_t chip_len;
78     uint8_t mappings;
79     uint8_t width;
80     uint8_t be;
81     int wcycle; /* if 0, the flash is read normally */
82     int bypass;
83     int ro;
84     uint8_t cmd;
85     uint8_t status;
86     /* FIXME: implement array device properties */
87     uint16_t ident0;
88     uint16_t ident1;
89     uint16_t ident2;
90     uint16_t ident3;
91     uint16_t unlock_addr0;
92     uint16_t unlock_addr1;
93     uint8_t cfi_table[0x4d];
94     QEMUTimer timer;
95     /*
96      * The device replicates the flash memory across its memory space.  Emulate
97      * that by having a container (.mem) filled with an array of aliases
98      * (.mem_mappings) pointing to the flash memory (.orig_mem).
99      */
100     MemoryRegion mem;
101     MemoryRegion *mem_mappings;    /* array; one per mapping */
102     MemoryRegion orig_mem;
103     bool rom_mode;
104     int read_counter; /* used for lazy switch-back to rom mode */
105     int sectors_to_erase;
106     uint64_t erase_time_remaining;
107     unsigned long *sector_erase_map;
108     char *name;
109     void *storage;
110 };
111 
112 /*
113  * Toggle status bit DQ7.
114  */
115 static inline void toggle_dq7(PFlashCFI02 *pfl)
116 {
117     pfl->status ^= 0x80;
118 }
119 
120 /*
121  * Set status bit DQ7 to bit 7 of value.
122  */
123 static inline void set_dq7(PFlashCFI02 *pfl, uint8_t value)
124 {
125     pfl->status &= 0x7F;
126     pfl->status |= value & 0x80;
127 }
128 
129 /*
130  * Toggle status bit DQ6.
131  */
132 static inline void toggle_dq6(PFlashCFI02 *pfl)
133 {
134     pfl->status ^= 0x40;
135 }
136 
137 /*
138  * Turn on DQ3.
139  */
140 static inline void assert_dq3(PFlashCFI02 *pfl)
141 {
142     pfl->status |= 0x08;
143 }
144 
145 /*
146  * Turn off DQ3.
147  */
148 static inline void reset_dq3(PFlashCFI02 *pfl)
149 {
150     pfl->status &= ~0x08;
151 }
152 
153 /*
154  * Toggle status bit DQ2.
155  */
156 static inline void toggle_dq2(PFlashCFI02 *pfl)
157 {
158     pfl->status ^= 0x04;
159 }
160 
161 /*
162  * Set up replicated mappings of the same region.
163  */
164 static void pflash_setup_mappings(PFlashCFI02 *pfl)
165 {
166     unsigned i;
167     hwaddr size = memory_region_size(&pfl->orig_mem);
168 
169     memory_region_init(&pfl->mem, OBJECT(pfl), "pflash", pfl->mappings * size);
170     pfl->mem_mappings = g_new(MemoryRegion, pfl->mappings);
171     for (i = 0; i < pfl->mappings; ++i) {
172         memory_region_init_alias(&pfl->mem_mappings[i], OBJECT(pfl),
173                                  "pflash-alias", &pfl->orig_mem, 0, size);
174         memory_region_add_subregion(&pfl->mem, i * size, &pfl->mem_mappings[i]);
175     }
176     pfl->rom_mode = true;
177 }
178 
179 static void pflash_reset_state_machine(PFlashCFI02 *pfl)
180 {
181     trace_pflash_reset(pfl->name);
182     pfl->cmd = 0x00;
183     pfl->wcycle = 0;
184 }
185 
186 static void pflash_mode_read_array(PFlashCFI02 *pfl)
187 {
188     trace_pflash_mode_read_array(pfl->name);
189     pflash_reset_state_machine(pfl);
190     pfl->rom_mode = true;
191     memory_region_rom_device_set_romd(&pfl->orig_mem, true);
192 }
193 
194 static size_t pflash_regions_count(PFlashCFI02 *pfl)
195 {
196     return pfl->cfi_table[0x2c];
197 }
198 
199 /*
200  * Returns the time it takes to erase the number of sectors scheduled for
201  * erasure based on CFI address 0x21 which is "Typical timeout per individual
202  * block erase 2^N ms."
203  */
204 static uint64_t pflash_erase_time(PFlashCFI02 *pfl)
205 {
206     /*
207      * If there are no sectors to erase (which can happen if all of the sectors
208      * to be erased are protected), then erase takes 100 us. Protected sectors
209      * aren't supported so this should never happen.
210      */
211     return ((1ULL << pfl->cfi_table[0x21]) * pfl->sectors_to_erase) * SCALE_US;
212 }
213 
214 /*
215  * Returns true if the device is currently in erase suspend mode.
216  */
217 static inline bool pflash_erase_suspend_mode(PFlashCFI02 *pfl)
218 {
219     return pfl->erase_time_remaining > 0;
220 }
221 
222 static void pflash_timer(void *opaque)
223 {
224     PFlashCFI02 *pfl = opaque;
225 
226     trace_pflash_timer_expired(pfl->name, pfl->cmd);
227     if (pfl->cmd == 0x30) {
228         /*
229          * Sector erase. If DQ3 is 0 when the timer expires, then the 50
230          * us erase timeout has expired so we need to start the timer for the
231          * sector erase algorithm. Otherwise, the erase completed and we should
232          * go back to read array mode.
233          */
234         if ((pfl->status & 0x08) == 0) {
235             assert_dq3(pfl);
236             uint64_t timeout = pflash_erase_time(pfl);
237             timer_mod(&pfl->timer,
238                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
239             trace_pflash_erase_timeout(pfl->name, pfl->sectors_to_erase);
240             return;
241         }
242         trace_pflash_erase_complete(pfl->name);
243         bitmap_zero(pfl->sector_erase_map, pfl->total_sectors);
244         pfl->sectors_to_erase = 0;
245         reset_dq3(pfl);
246     }
247 
248     /* Reset flash */
249     toggle_dq7(pfl);
250     if (pfl->bypass) {
251         pfl->wcycle = 2;
252         pfl->cmd = 0;
253     } else {
254         pflash_mode_read_array(pfl);
255     }
256 }
257 
258 /*
259  * Read data from flash.
260  */
261 static uint64_t pflash_data_read(PFlashCFI02 *pfl, hwaddr offset,
262                                  unsigned int width)
263 {
264     uint8_t *p = (uint8_t *)pfl->storage + offset;
265     uint64_t ret = pfl->be ? ldn_be_p(p, width) : ldn_le_p(p, width);
266     trace_pflash_data_read(pfl->name, offset, width, ret);
267     return ret;
268 }
269 
270 typedef struct {
271     uint32_t len;
272     uint32_t num;
273 } SectorInfo;
274 
275 /*
276  * offset should be a byte offset of the QEMU device and _not_ a device
277  * offset.
278  */
279 static SectorInfo pflash_sector_info(PFlashCFI02 *pfl, hwaddr offset)
280 {
281     assert(offset < pfl->chip_len);
282     hwaddr addr = 0;
283     uint32_t sector_num = 0;
284     for (int i = 0; i < pflash_regions_count(pfl); ++i) {
285         uint64_t region_size = (uint64_t)pfl->nb_blocs[i] * pfl->sector_len[i];
286         if (addr <= offset && offset < addr + region_size) {
287             return (SectorInfo) {
288                 .len = pfl->sector_len[i],
289                 .num = sector_num + (offset - addr) / pfl->sector_len[i],
290             };
291         }
292         sector_num += pfl->nb_blocs[i];
293         addr += region_size;
294     }
295     abort();
296 }
297 
298 /*
299  * Returns true if the offset refers to a flash sector that is currently being
300  * erased.
301  */
302 static bool pflash_sector_is_erasing(PFlashCFI02 *pfl, hwaddr offset)
303 {
304     long sector_num = pflash_sector_info(pfl, offset).num;
305     return test_bit(sector_num, pfl->sector_erase_map);
306 }
307 
308 static uint64_t pflash_read(void *opaque, hwaddr offset, unsigned int width)
309 {
310     PFlashCFI02 *pfl = opaque;
311     hwaddr boff;
312     uint64_t ret;
313 
314     /* Lazy reset to ROMD mode after a certain amount of read accesses */
315     if (!pfl->rom_mode && pfl->wcycle == 0 &&
316         ++pfl->read_counter > PFLASH_LAZY_ROMD_THRESHOLD) {
317         pflash_mode_read_array(pfl);
318     }
319     offset &= pfl->chip_len - 1;
320     boff = offset & 0xFF;
321     if (pfl->width == 2) {
322         boff = boff >> 1;
323     } else if (pfl->width == 4) {
324         boff = boff >> 2;
325     }
326     switch (pfl->cmd) {
327     default:
328         /* This should never happen : reset state & treat it as a read*/
329         trace_pflash_read_unknown_state(pfl->name, pfl->cmd);
330         pflash_reset_state_machine(pfl);
331         /* fall through to the read code */
332     case 0x80: /* Erase (unlock) */
333         /* We accept reads during second unlock sequence... */
334     case 0x00:
335         if (pflash_erase_suspend_mode(pfl) &&
336             pflash_sector_is_erasing(pfl, offset)) {
337             /* Toggle bit 2, but not 6. */
338             toggle_dq2(pfl);
339             /* Status register read */
340             ret = pfl->status;
341             trace_pflash_read_status(pfl->name, ret);
342             break;
343         }
344         /* Flash area read */
345         ret = pflash_data_read(pfl, offset, width);
346         break;
347     case 0x90: /* flash ID read */
348         switch (boff) {
349         case 0x00:
350         case 0x01:
351             ret = boff & 0x01 ? pfl->ident1 : pfl->ident0;
352             break;
353         case 0x02:
354             ret = 0x00; /* Pretend all sectors are unprotected */
355             break;
356         case 0x0E:
357         case 0x0F:
358             ret = boff & 0x01 ? pfl->ident3 : pfl->ident2;
359             if (ret != (uint8_t)-1) {
360                 break;
361             }
362             /* Fall through to data read. */
363         default:
364             ret = pflash_data_read(pfl, offset, width);
365         }
366         trace_pflash_read_done(pfl->name, boff, ret);
367         break;
368     case 0x10: /* Chip Erase */
369     case 0x30: /* Sector Erase */
370         /* Toggle bit 2 during erase, but not program. */
371         toggle_dq2(pfl);
372         /* fall through */
373     case 0xA0: /* Program */
374         /* Toggle bit 6 */
375         toggle_dq6(pfl);
376         /* Status register read */
377         ret = pfl->status;
378         trace_pflash_read_status(pfl->name, ret);
379         break;
380     case 0x98:
381         /* CFI query mode */
382         if (boff < sizeof(pfl->cfi_table)) {
383             ret = pfl->cfi_table[boff];
384         } else {
385             ret = 0;
386         }
387         break;
388     }
389     trace_pflash_io_read(pfl->name, offset, width, ret, pfl->cmd, pfl->wcycle);
390 
391     return ret;
392 }
393 
394 /* update flash content on disk */
395 static void pflash_update(PFlashCFI02 *pfl, int offset, int size)
396 {
397     int offset_end;
398     int ret;
399     if (pfl->blk) {
400         offset_end = offset + size;
401         /* widen to sector boundaries */
402         offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
403         offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
404         ret = blk_pwrite(pfl->blk, offset, pfl->storage + offset,
405                    offset_end - offset, 0);
406         if (ret < 0) {
407             /* TODO set error bit in status */
408             error_report("Could not update PFLASH: %s", strerror(-ret));
409         }
410     }
411 }
412 
413 static void pflash_sector_erase(PFlashCFI02 *pfl, hwaddr offset)
414 {
415     SectorInfo sector_info = pflash_sector_info(pfl, offset);
416     uint64_t sector_len = sector_info.len;
417     offset &= ~(sector_len - 1);
418     trace_pflash_sector_erase_start(pfl->name, 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(pfl->name, 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             pfl->rom_mode = false;
469             memory_region_rom_device_set_romd(&pfl->orig_mem, false);
470         }
471         pfl->read_counter = 0;
472         /* We're in read mode */
473     check_unlock0:
474         if (boff == 0x55 && cmd == 0x98) {
475             /* Enter CFI query mode */
476             pfl->wcycle = WCYCLE_CFI;
477             pfl->cmd = 0x98;
478             return;
479         }
480         /* Handle erase resume in erase suspend mode, otherwise reset. */
481         if (cmd == 0x30) { /* Erase Resume */
482             if (pflash_erase_suspend_mode(pfl)) {
483                 /* Resume the erase. */
484                 timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
485                           pfl->erase_time_remaining);
486                 pfl->erase_time_remaining = 0;
487                 pfl->wcycle = 6;
488                 pfl->cmd = 0x30;
489                 set_dq7(pfl, 0x00);
490                 assert_dq3(pfl);
491                 return;
492             }
493             goto reset_flash;
494         }
495         /* Ignore erase suspend. */
496         if (cmd == 0xB0) { /* Erase Suspend */
497             return;
498         }
499         if (boff != pfl->unlock_addr0 || cmd != 0xAA) {
500             trace_pflash_unlock0_failed(pfl->name, boff,
501                                         cmd, pfl->unlock_addr0);
502             goto reset_flash;
503         }
504         trace_pflash_write(pfl->name, "unlock sequence started");
505         break;
506     case 1:
507         /* We started an unlock sequence */
508     check_unlock1:
509         if (boff != pfl->unlock_addr1 || cmd != 0x55) {
510             trace_pflash_unlock1_failed(pfl->name, boff, cmd);
511             goto reset_flash;
512         }
513         trace_pflash_write(pfl->name, "unlock sequence done");
514         break;
515     case 2:
516         /* We finished an unlock sequence */
517         if (!pfl->bypass && boff != pfl->unlock_addr0) {
518             trace_pflash_write_failed(pfl->name, 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             trace_pflash_write_start(pfl->name, cmd);
530             break;
531         default:
532             trace_pflash_write_unknown(pfl->name, 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(pfl->name, 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             trace_pflash_write_invalid(pfl->name, pfl->cmd);
589             goto reset_flash;
590         }
591     case 4:
592         switch (pfl->cmd) {
593         case 0xA0: /* Program */
594             /* Ignore writes while flash data write is occurring */
595             /* As we suppose write is immediate, this should never happen */
596             return;
597         case 0x80: /* Erase */
598             goto check_unlock1;
599         default:
600             /* Should never happen */
601             trace_pflash_write_invalid_state(pfl->name, pfl->cmd, 5);
602             goto reset_flash;
603         }
604         break;
605     case 5:
606         if (pflash_erase_suspend_mode(pfl)) {
607             /* Erasing is not supported in erase suspend mode. */
608             goto reset_flash;
609         }
610         switch (cmd) {
611         case 0x10: /* Chip Erase */
612             if (boff != pfl->unlock_addr0) {
613                 trace_pflash_chip_erase_invalid(pfl->name, offset);
614                 goto reset_flash;
615             }
616             /* Chip erase */
617             trace_pflash_chip_erase_start(pfl->name);
618             if (!pfl->ro) {
619                 memset(pfl->storage, 0xff, pfl->chip_len);
620                 pflash_update(pfl, 0, pfl->chip_len);
621             }
622             set_dq7(pfl, 0x00);
623             /* Wait the time specified at CFI address 0x22. */
624             timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
625                       (1ULL << pfl->cfi_table[0x22]) * SCALE_MS);
626             break;
627         case 0x30: /* Sector erase */
628             pflash_sector_erase(pfl, offset);
629             break;
630         default:
631             trace_pflash_write_invalid_command(pfl->name, cmd);
632             goto reset_flash;
633         }
634         pfl->cmd = cmd;
635         break;
636     case 6:
637         switch (pfl->cmd) {
638         case 0x10: /* Chip Erase */
639             /* Ignore writes during chip erase */
640             return;
641         case 0x30: /* Sector erase */
642             if (cmd == 0xB0) {
643                 /*
644                  * If erase suspend happens during the erase timeout (so DQ3 is
645                  * 0), then the device suspends erasing immediately. Set the
646                  * remaining time to be the total time to erase. Otherwise,
647                  * there is a maximum amount of time it can take to enter
648                  * suspend mode. Let's ignore that and suspend immediately and
649                  * set the remaining time to the actual time remaining on the
650                  * timer.
651                  */
652                 if ((pfl->status & 0x08) == 0) {
653                     pfl->erase_time_remaining = pflash_erase_time(pfl);
654                 } else {
655                     int64_t delta = timer_expire_time_ns(&pfl->timer) -
656                         qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
657                     /* Make sure we have a positive time remaining. */
658                     pfl->erase_time_remaining = delta <= 0 ? 1 : delta;
659                 }
660                 reset_dq3(pfl);
661                 timer_del(&pfl->timer);
662                 pflash_reset_state_machine(pfl);
663                 return;
664             }
665             /*
666              * If DQ3 is 0, additional sector erase commands can be
667              * written and anything else (other than an erase suspend) resets
668              * the device.
669              */
670             if ((pfl->status & 0x08) == 0) {
671                 if (cmd == 0x30) {
672                     pflash_sector_erase(pfl, offset);
673                 } else {
674                     goto reset_flash;
675                 }
676             }
677             /* Ignore writes during the actual erase. */
678             return;
679         default:
680             /* Should never happen */
681             trace_pflash_write_invalid_state(pfl->name, pfl->cmd, 6);
682             goto reset_flash;
683         }
684         break;
685     /* Special values for CFI queries */
686     case WCYCLE_CFI:
687     case WCYCLE_AUTOSELECT_CFI:
688         trace_pflash_write(pfl->name, "invalid write in CFI query mode");
689         goto reset_flash;
690     default:
691         /* Should never happen */
692         trace_pflash_write(pfl->name, "invalid write state (wc 7)");
693         goto reset_flash;
694     }
695     pfl->wcycle++;
696 
697     return;
698 
699     /* Reset flash */
700  reset_flash:
701     pfl->bypass = 0;
702     pflash_reset_state_machine(pfl);
703     return;
704 
705  do_bypass:
706     pfl->wcycle = 2;
707     pfl->cmd = 0;
708 }
709 
710 static const MemoryRegionOps pflash_cfi02_ops = {
711     .read = pflash_read,
712     .write = pflash_write,
713     .valid.min_access_size = 1,
714     .valid.max_access_size = 4,
715     .endianness = DEVICE_NATIVE_ENDIAN,
716 };
717 
718 static void pflash_cfi02_fill_cfi_table(PFlashCFI02 *pfl, int nb_regions)
719 {
720     /* Hardcoded CFI table (mostly from SG29 Spansion flash) */
721     const uint16_t pri_ofs = 0x40;
722     /* Standard "QRY" string */
723     pfl->cfi_table[0x10] = 'Q';
724     pfl->cfi_table[0x11] = 'R';
725     pfl->cfi_table[0x12] = 'Y';
726     /* Command set (AMD/Fujitsu) */
727     pfl->cfi_table[0x13] = 0x02;
728     pfl->cfi_table[0x14] = 0x00;
729     /* Primary extended table address */
730     pfl->cfi_table[0x15] = pri_ofs;
731     pfl->cfi_table[0x16] = pri_ofs >> 8;
732     /* Alternate command set (none) */
733     pfl->cfi_table[0x17] = 0x00;
734     pfl->cfi_table[0x18] = 0x00;
735     /* Alternate extended table (none) */
736     pfl->cfi_table[0x19] = 0x00;
737     pfl->cfi_table[0x1A] = 0x00;
738     /* Vcc min */
739     pfl->cfi_table[0x1B] = 0x27;
740     /* Vcc max */
741     pfl->cfi_table[0x1C] = 0x36;
742     /* Vpp min (no Vpp pin) */
743     pfl->cfi_table[0x1D] = 0x00;
744     /* Vpp max (no Vpp pin) */
745     pfl->cfi_table[0x1E] = 0x00;
746     /* Timeout per single byte/word write (128 ms) */
747     pfl->cfi_table[0x1F] = 0x07;
748     /* Timeout for min size buffer write (NA) */
749     pfl->cfi_table[0x20] = 0x00;
750     /* Typical timeout for block erase (512 ms) */
751     pfl->cfi_table[0x21] = 0x09;
752     /* Typical timeout for full chip erase (4096 ms) */
753     pfl->cfi_table[0x22] = 0x0C;
754     /* Reserved */
755     pfl->cfi_table[0x23] = 0x01;
756     /* Max timeout for buffer write (NA) */
757     pfl->cfi_table[0x24] = 0x00;
758     /* Max timeout for block erase */
759     pfl->cfi_table[0x25] = 0x0A;
760     /* Max timeout for chip erase */
761     pfl->cfi_table[0x26] = 0x0D;
762     /* Device size */
763     pfl->cfi_table[0x27] = ctz32(pfl->chip_len);
764     /* Flash device interface (8 & 16 bits) */
765     pfl->cfi_table[0x28] = 0x02;
766     pfl->cfi_table[0x29] = 0x00;
767     /* Max number of bytes in multi-bytes write */
768     /*
769      * XXX: disable buffered write as it's not supported
770      * pfl->cfi_table[0x2A] = 0x05;
771      */
772     pfl->cfi_table[0x2A] = 0x00;
773     pfl->cfi_table[0x2B] = 0x00;
774     /* Number of erase block regions */
775     pfl->cfi_table[0x2c] = nb_regions;
776     /* Erase block regions */
777     for (int i = 0; i < nb_regions; ++i) {
778         uint32_t sector_len_per_device = pfl->sector_len[i];
779         pfl->cfi_table[0x2d + 4 * i] = pfl->nb_blocs[i] - 1;
780         pfl->cfi_table[0x2e + 4 * i] = (pfl->nb_blocs[i] - 1) >> 8;
781         pfl->cfi_table[0x2f + 4 * i] = sector_len_per_device >> 8;
782         pfl->cfi_table[0x30 + 4 * i] = sector_len_per_device >> 16;
783     }
784     assert(0x2c + 4 * nb_regions < pri_ofs);
785 
786     /* Extended */
787     pfl->cfi_table[0x00 + pri_ofs] = 'P';
788     pfl->cfi_table[0x01 + pri_ofs] = 'R';
789     pfl->cfi_table[0x02 + pri_ofs] = 'I';
790 
791     /* Extended version 1.0 */
792     pfl->cfi_table[0x03 + pri_ofs] = '1';
793     pfl->cfi_table[0x04 + pri_ofs] = '0';
794 
795     /* Address sensitive unlock required. */
796     pfl->cfi_table[0x05 + pri_ofs] = 0x00;
797     /* Erase suspend to read/write. */
798     pfl->cfi_table[0x06 + pri_ofs] = 0x02;
799     /* Sector protect not supported. */
800     pfl->cfi_table[0x07 + pri_ofs] = 0x00;
801     /* Temporary sector unprotect not supported. */
802     pfl->cfi_table[0x08 + pri_ofs] = 0x00;
803 
804     /* Sector protect/unprotect scheme. */
805     pfl->cfi_table[0x09 + pri_ofs] = 0x00;
806 
807     /* Simultaneous operation not supported. */
808     pfl->cfi_table[0x0a + pri_ofs] = 0x00;
809     /* Burst mode not supported. */
810     pfl->cfi_table[0x0b + pri_ofs] = 0x00;
811     /* Page mode not supported. */
812     pfl->cfi_table[0x0c + pri_ofs] = 0x00;
813     assert(0x0c + pri_ofs < ARRAY_SIZE(pfl->cfi_table));
814 }
815 
816 static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
817 {
818     ERRP_GUARD();
819     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
820     int ret;
821 
822     if (pfl->uniform_sector_len == 0 && pfl->sector_len[0] == 0) {
823         error_setg(errp, "attribute \"sector-length\" not specified or zero.");
824         return;
825     }
826     if (pfl->uniform_nb_blocs == 0 && pfl->nb_blocs[0] == 0) {
827         error_setg(errp, "attribute \"num-blocks\" not specified or zero.");
828         return;
829     }
830     if (pfl->name == NULL) {
831         error_setg(errp, "attribute \"name\" not specified.");
832         return;
833     }
834 
835     int nb_regions;
836     pfl->chip_len = 0;
837     pfl->total_sectors = 0;
838     for (nb_regions = 0; nb_regions < PFLASH_MAX_ERASE_REGIONS; ++nb_regions) {
839         if (pfl->nb_blocs[nb_regions] == 0) {
840             break;
841         }
842         pfl->total_sectors += pfl->nb_blocs[nb_regions];
843         uint64_t sector_len_per_device = pfl->sector_len[nb_regions];
844 
845         /*
846          * The size of each flash sector must be a power of 2 and it must be
847          * aligned at the same power of 2.
848          */
849         if (sector_len_per_device & 0xff ||
850             sector_len_per_device >= (1 << 24) ||
851             !is_power_of_2(sector_len_per_device))
852         {
853             error_setg(errp, "unsupported configuration: "
854                        "sector length[%d] per device = %" PRIx64 ".",
855                        nb_regions, sector_len_per_device);
856             return;
857         }
858         if (pfl->chip_len & (sector_len_per_device - 1)) {
859             error_setg(errp, "unsupported configuration: "
860                        "flash region %d not correctly aligned.",
861                        nb_regions);
862             return;
863         }
864 
865         pfl->chip_len += (uint64_t)pfl->sector_len[nb_regions] *
866                           pfl->nb_blocs[nb_regions];
867     }
868 
869     uint64_t uniform_len = (uint64_t)pfl->uniform_nb_blocs *
870                            pfl->uniform_sector_len;
871     if (nb_regions == 0) {
872         nb_regions = 1;
873         pfl->nb_blocs[0] = pfl->uniform_nb_blocs;
874         pfl->sector_len[0] = pfl->uniform_sector_len;
875         pfl->chip_len = uniform_len;
876         pfl->total_sectors = pfl->uniform_nb_blocs;
877     } else if (uniform_len != 0 && uniform_len != pfl->chip_len) {
878         error_setg(errp, "\"num-blocks\"*\"sector-length\" "
879                    "different from \"num-blocks0\"*\'sector-length0\" + ... + "
880                    "\"num-blocks3\"*\"sector-length3\"");
881         return;
882     }
883 
884     memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
885                                   &pflash_cfi02_ops, pfl, pfl->name,
886                                   pfl->chip_len, errp);
887     if (*errp) {
888         return;
889     }
890 
891     pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem);
892 
893     if (pfl->blk) {
894         uint64_t perm;
895         pfl->ro = !blk_supports_write_perm(pfl->blk);
896         perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE);
897         ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp);
898         if (ret < 0) {
899             return;
900         }
901     } else {
902         pfl->ro = 0;
903     }
904 
905     if (pfl->blk) {
906         if (!blk_check_size_and_read_all(pfl->blk, pfl->storage,
907                                          pfl->chip_len, errp)) {
908             vmstate_unregister_ram(&pfl->orig_mem, DEVICE(pfl));
909             return;
910         }
911     }
912 
913     /* Only 11 bits are used in the comparison. */
914     pfl->unlock_addr0 &= 0x7FF;
915     pfl->unlock_addr1 &= 0x7FF;
916 
917     /* Allocate memory for a bitmap for sectors being erased. */
918     pfl->sector_erase_map = bitmap_new(pfl->total_sectors);
919 
920     pflash_setup_mappings(pfl);
921     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem);
922 
923     timer_init_ns(&pfl->timer, QEMU_CLOCK_VIRTUAL, pflash_timer, pfl);
924     pfl->status = 0;
925 
926     pflash_cfi02_fill_cfi_table(pfl, nb_regions);
927 }
928 
929 static void pflash_cfi02_reset(DeviceState *dev)
930 {
931     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
932 
933     pflash_reset_state_machine(pfl);
934 }
935 
936 static Property pflash_cfi02_properties[] = {
937     DEFINE_PROP_DRIVE("drive", PFlashCFI02, blk),
938     DEFINE_PROP_UINT32("num-blocks", PFlashCFI02, uniform_nb_blocs, 0),
939     DEFINE_PROP_UINT32("sector-length", PFlashCFI02, uniform_sector_len, 0),
940     DEFINE_PROP_UINT32("num-blocks0", PFlashCFI02, nb_blocs[0], 0),
941     DEFINE_PROP_UINT32("sector-length0", PFlashCFI02, sector_len[0], 0),
942     DEFINE_PROP_UINT32("num-blocks1", PFlashCFI02, nb_blocs[1], 0),
943     DEFINE_PROP_UINT32("sector-length1", PFlashCFI02, sector_len[1], 0),
944     DEFINE_PROP_UINT32("num-blocks2", PFlashCFI02, nb_blocs[2], 0),
945     DEFINE_PROP_UINT32("sector-length2", PFlashCFI02, sector_len[2], 0),
946     DEFINE_PROP_UINT32("num-blocks3", PFlashCFI02, nb_blocs[3], 0),
947     DEFINE_PROP_UINT32("sector-length3", PFlashCFI02, sector_len[3], 0),
948     DEFINE_PROP_UINT8("width", PFlashCFI02, width, 0),
949     DEFINE_PROP_UINT8("mappings", PFlashCFI02, mappings, 0),
950     DEFINE_PROP_UINT8("big-endian", PFlashCFI02, be, 0),
951     DEFINE_PROP_UINT16("id0", PFlashCFI02, ident0, 0),
952     DEFINE_PROP_UINT16("id1", PFlashCFI02, ident1, 0),
953     DEFINE_PROP_UINT16("id2", PFlashCFI02, ident2, 0),
954     DEFINE_PROP_UINT16("id3", PFlashCFI02, ident3, 0),
955     DEFINE_PROP_UINT16("unlock-addr0", PFlashCFI02, unlock_addr0, 0),
956     DEFINE_PROP_UINT16("unlock-addr1", PFlashCFI02, unlock_addr1, 0),
957     DEFINE_PROP_STRING("name", PFlashCFI02, name),
958     DEFINE_PROP_END_OF_LIST(),
959 };
960 
961 static void pflash_cfi02_unrealize(DeviceState *dev)
962 {
963     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
964     timer_del(&pfl->timer);
965     g_free(pfl->sector_erase_map);
966 }
967 
968 static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
969 {
970     DeviceClass *dc = DEVICE_CLASS(klass);
971 
972     dc->realize = pflash_cfi02_realize;
973     dc->reset = pflash_cfi02_reset;
974     dc->unrealize = pflash_cfi02_unrealize;
975     device_class_set_props(dc, pflash_cfi02_properties);
976     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
977 }
978 
979 static const TypeInfo pflash_cfi02_info = {
980     .name           = TYPE_PFLASH_CFI02,
981     .parent         = TYPE_SYS_BUS_DEVICE,
982     .instance_size  = sizeof(PFlashCFI02),
983     .class_init     = pflash_cfi02_class_init,
984 };
985 
986 static void pflash_cfi02_register_types(void)
987 {
988     type_register_static(&pflash_cfi02_info);
989 }
990 
991 type_init(pflash_cfi02_register_types)
992 
993 PFlashCFI02 *pflash_cfi02_register(hwaddr base,
994                                    const char *name,
995                                    hwaddr size,
996                                    BlockBackend *blk,
997                                    uint32_t sector_len,
998                                    int nb_mappings, int width,
999                                    uint16_t id0, uint16_t id1,
1000                                    uint16_t id2, uint16_t id3,
1001                                    uint16_t unlock_addr0,
1002                                    uint16_t unlock_addr1,
1003                                    int be)
1004 {
1005     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI02);
1006 
1007     if (blk) {
1008         qdev_prop_set_drive(dev, "drive", blk);
1009     }
1010     assert(QEMU_IS_ALIGNED(size, sector_len));
1011     qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
1012     qdev_prop_set_uint32(dev, "sector-length", sector_len);
1013     qdev_prop_set_uint8(dev, "width", width);
1014     qdev_prop_set_uint8(dev, "mappings", nb_mappings);
1015     qdev_prop_set_uint8(dev, "big-endian", !!be);
1016     qdev_prop_set_uint16(dev, "id0", id0);
1017     qdev_prop_set_uint16(dev, "id1", id1);
1018     qdev_prop_set_uint16(dev, "id2", id2);
1019     qdev_prop_set_uint16(dev, "id3", id3);
1020     qdev_prop_set_uint16(dev, "unlock-addr0", unlock_addr0);
1021     qdev_prop_set_uint16(dev, "unlock-addr1", unlock_addr1);
1022     qdev_prop_set_string(dev, "name", name);
1023     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
1024 
1025     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
1026     return PFLASH_CFI02(dev);
1027 }
1028