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pflash_cfi02.c (33756B)


      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 }
    177 
    178 static void pflash_reset_state_machine(PFlashCFI02 *pfl)
    179 {
    180     trace_pflash_reset(pfl->name);
    181     pfl->cmd = 0x00;
    182     pfl->wcycle = 0;
    183 }
    184 
    185 static void pflash_mode_read_array(PFlashCFI02 *pfl)
    186 {
    187     trace_pflash_mode_read_array(pfl->name);
    188     pflash_reset_state_machine(pfl);
    189     pfl->rom_mode = true;
    190     memory_region_rom_device_set_romd(&pfl->orig_mem, true);
    191 }
    192 
    193 static size_t pflash_regions_count(PFlashCFI02 *pfl)
    194 {
    195     return pfl->cfi_table[0x2c];
    196 }
    197 
    198 /*
    199  * Returns the time it takes to erase the number of sectors scheduled for
    200  * erasure based on CFI address 0x21 which is "Typical timeout per individual
    201  * block erase 2^N ms."
    202  */
    203 static uint64_t pflash_erase_time(PFlashCFI02 *pfl)
    204 {
    205     /*
    206      * If there are no sectors to erase (which can happen if all of the sectors
    207      * to be erased are protected), then erase takes 100 us. Protected sectors
    208      * aren't supported so this should never happen.
    209      */
    210     return ((1ULL << pfl->cfi_table[0x21]) * pfl->sectors_to_erase) * SCALE_US;
    211 }
    212 
    213 /*
    214  * Returns true if the device is currently in erase suspend mode.
    215  */
    216 static inline bool pflash_erase_suspend_mode(PFlashCFI02 *pfl)
    217 {
    218     return pfl->erase_time_remaining > 0;
    219 }
    220 
    221 static void pflash_timer(void *opaque)
    222 {
    223     PFlashCFI02 *pfl = opaque;
    224 
    225     trace_pflash_timer_expired(pfl->name, pfl->cmd);
    226     if (pfl->cmd == 0x30) {
    227         /*
    228          * Sector erase. If DQ3 is 0 when the timer expires, then the 50
    229          * us erase timeout has expired so we need to start the timer for the
    230          * sector erase algorithm. Otherwise, the erase completed and we should
    231          * go back to read array mode.
    232          */
    233         if ((pfl->status & 0x08) == 0) {
    234             assert_dq3(pfl);
    235             uint64_t timeout = pflash_erase_time(pfl);
    236             timer_mod(&pfl->timer,
    237                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
    238             trace_pflash_erase_timeout(pfl->name, pfl->sectors_to_erase);
    239             return;
    240         }
    241         trace_pflash_erase_complete(pfl->name);
    242         bitmap_zero(pfl->sector_erase_map, pfl->total_sectors);
    243         pfl->sectors_to_erase = 0;
    244         reset_dq3(pfl);
    245     }
    246 
    247     /* Reset flash */
    248     toggle_dq7(pfl);
    249     if (pfl->bypass) {
    250         pfl->wcycle = 2;
    251         pfl->cmd = 0;
    252     } else {
    253         pflash_mode_read_array(pfl);
    254     }
    255 }
    256 
    257 /*
    258  * Read data from flash.
    259  */
    260 static uint64_t pflash_data_read(PFlashCFI02 *pfl, hwaddr offset,
    261                                  unsigned int width)
    262 {
    263     uint8_t *p = (uint8_t *)pfl->storage + offset;
    264     uint64_t ret = pfl->be ? ldn_be_p(p, width) : ldn_le_p(p, width);
    265     trace_pflash_data_read(pfl->name, offset, width, ret);
    266     return ret;
    267 }
    268 
    269 typedef struct {
    270     uint32_t len;
    271     uint32_t num;
    272 } SectorInfo;
    273 
    274 /*
    275  * offset should be a byte offset of the QEMU device and _not_ a device
    276  * offset.
    277  */
    278 static SectorInfo pflash_sector_info(PFlashCFI02 *pfl, hwaddr offset)
    279 {
    280     assert(offset < pfl->chip_len);
    281     hwaddr addr = 0;
    282     uint32_t sector_num = 0;
    283     for (int i = 0; i < pflash_regions_count(pfl); ++i) {
    284         uint64_t region_size = (uint64_t)pfl->nb_blocs[i] * pfl->sector_len[i];
    285         if (addr <= offset && offset < addr + region_size) {
    286             return (SectorInfo) {
    287                 .len = pfl->sector_len[i],
    288                 .num = sector_num + (offset - addr) / pfl->sector_len[i],
    289             };
    290         }
    291         sector_num += pfl->nb_blocs[i];
    292         addr += region_size;
    293     }
    294     abort();
    295 }
    296 
    297 /*
    298  * Returns true if the offset refers to a flash sector that is currently being
    299  * erased.
    300  */
    301 static bool pflash_sector_is_erasing(PFlashCFI02 *pfl, hwaddr offset)
    302 {
    303     long sector_num = pflash_sector_info(pfl, offset).num;
    304     return test_bit(sector_num, pfl->sector_erase_map);
    305 }
    306 
    307 static uint64_t pflash_read(void *opaque, hwaddr offset, unsigned int width)
    308 {
    309     PFlashCFI02 *pfl = opaque;
    310     hwaddr boff;
    311     uint64_t ret;
    312 
    313     /* Lazy reset to ROMD mode after a certain amount of read accesses */
    314     if (!pfl->rom_mode && pfl->wcycle == 0 &&
    315         ++pfl->read_counter > PFLASH_LAZY_ROMD_THRESHOLD) {
    316         pflash_mode_read_array(pfl);
    317     }
    318     offset &= pfl->chip_len - 1;
    319     boff = offset & 0xFF;
    320     if (pfl->width == 2) {
    321         boff = boff >> 1;
    322     } else if (pfl->width == 4) {
    323         boff = boff >> 2;
    324     }
    325     switch (pfl->cmd) {
    326     default:
    327         /* This should never happen : reset state & treat it as a read*/
    328         trace_pflash_read_unknown_state(pfl->name, pfl->cmd);
    329         pflash_reset_state_machine(pfl);
    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             trace_pflash_read_status(pfl->name, 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         trace_pflash_read_done(pfl->name, 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         trace_pflash_read_status(pfl->name, 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(pfl->name, 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, offset_end - offset,
    404                          pfl->storage + 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     trace_pflash_sector_erase_start(pfl->name, pfl->width * 2, offset,
    418                                     pfl->width * 2, offset + sector_len - 1);
    419     if (!pfl->ro) {
    420         uint8_t *p = pfl->storage;
    421         memset(p + offset, 0xff, sector_len);
    422         pflash_update(pfl, offset, sector_len);
    423     }
    424     set_dq7(pfl, 0x00);
    425     ++pfl->sectors_to_erase;
    426     set_bit(sector_info.num, pfl->sector_erase_map);
    427     /* Set (or reset) the 50 us timer for additional erase commands.  */
    428     timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 50000);
    429 }
    430 
    431 static void pflash_write(void *opaque, hwaddr offset, uint64_t value,
    432                          unsigned int width)
    433 {
    434     PFlashCFI02 *pfl = opaque;
    435     hwaddr boff;
    436     uint8_t *p;
    437     uint8_t cmd;
    438 
    439     trace_pflash_io_write(pfl->name, offset, width, value, pfl->wcycle);
    440     cmd = value;
    441     if (pfl->cmd != 0xA0) {
    442         /* Reset does nothing during chip erase and sector erase. */
    443         if (cmd == 0xF0 && pfl->cmd != 0x10 && pfl->cmd != 0x30) {
    444             if (pfl->wcycle == WCYCLE_AUTOSELECT_CFI) {
    445                 /* Return to autoselect mode. */
    446                 pfl->wcycle = 3;
    447                 pfl->cmd = 0x90;
    448                 return;
    449             }
    450             goto reset_flash;
    451         }
    452     }
    453     offset &= pfl->chip_len - 1;
    454 
    455     boff = offset;
    456     if (pfl->width == 2) {
    457         boff = boff >> 1;
    458     } else if (pfl->width == 4) {
    459         boff = boff >> 2;
    460     }
    461     /* Only the least-significant 11 bits are used in most cases. */
    462     boff &= 0x7FF;
    463     switch (pfl->wcycle) {
    464     case 0:
    465         /* Set the device in I/O access mode if required */
    466         if (pfl->rom_mode) {
    467             pfl->rom_mode = false;
    468             memory_region_rom_device_set_romd(&pfl->orig_mem, false);
    469         }
    470         pfl->read_counter = 0;
    471         /* We're in read mode */
    472     check_unlock0:
    473         if (boff == 0x55 && cmd == 0x98) {
    474             /* Enter CFI query mode */
    475             pfl->wcycle = WCYCLE_CFI;
    476             pfl->cmd = 0x98;
    477             return;
    478         }
    479         /* Handle erase resume in erase suspend mode, otherwise reset. */
    480         if (cmd == 0x30) { /* Erase Resume */
    481             if (pflash_erase_suspend_mode(pfl)) {
    482                 /* Resume the erase. */
    483                 timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
    484                           pfl->erase_time_remaining);
    485                 pfl->erase_time_remaining = 0;
    486                 pfl->wcycle = 6;
    487                 pfl->cmd = 0x30;
    488                 set_dq7(pfl, 0x00);
    489                 assert_dq3(pfl);
    490                 return;
    491             }
    492             goto reset_flash;
    493         }
    494         /* Ignore erase suspend. */
    495         if (cmd == 0xB0) { /* Erase Suspend */
    496             return;
    497         }
    498         if (boff != pfl->unlock_addr0 || cmd != 0xAA) {
    499             trace_pflash_unlock0_failed(pfl->name, boff,
    500                                         cmd, pfl->unlock_addr0);
    501             goto reset_flash;
    502         }
    503         trace_pflash_write(pfl->name, "unlock sequence started");
    504         break;
    505     case 1:
    506         /* We started an unlock sequence */
    507     check_unlock1:
    508         if (boff != pfl->unlock_addr1 || cmd != 0x55) {
    509             trace_pflash_unlock1_failed(pfl->name, boff, cmd);
    510             goto reset_flash;
    511         }
    512         trace_pflash_write(pfl->name, "unlock sequence done");
    513         break;
    514     case 2:
    515         /* We finished an unlock sequence */
    516         if (!pfl->bypass && boff != pfl->unlock_addr0) {
    517             trace_pflash_write_failed(pfl->name, boff, cmd);
    518             goto reset_flash;
    519         }
    520         switch (cmd) {
    521         case 0x20:
    522             pfl->bypass = 1;
    523             goto do_bypass;
    524         case 0x80: /* Erase */
    525         case 0x90: /* Autoselect */
    526         case 0xA0: /* Program */
    527             pfl->cmd = cmd;
    528             trace_pflash_write_start(pfl->name, cmd);
    529             break;
    530         default:
    531             trace_pflash_write_unknown(pfl->name, cmd);
    532             goto reset_flash;
    533         }
    534         break;
    535     case 3:
    536         switch (pfl->cmd) {
    537         case 0x80: /* Erase */
    538             /* We need another unlock sequence */
    539             goto check_unlock0;
    540         case 0xA0: /* Program */
    541             if (pflash_erase_suspend_mode(pfl) &&
    542                 pflash_sector_is_erasing(pfl, offset)) {
    543                 /* Ignore writes to erasing sectors. */
    544                 if (pfl->bypass) {
    545                     goto do_bypass;
    546                 }
    547                 goto reset_flash;
    548             }
    549             trace_pflash_data_write(pfl->name, offset, width, value, 0);
    550             if (!pfl->ro) {
    551                 p = (uint8_t *)pfl->storage + offset;
    552                 if (pfl->be) {
    553                     uint64_t current = ldn_be_p(p, width);
    554                     stn_be_p(p, width, current & value);
    555                 } else {
    556                     uint64_t current = ldn_le_p(p, width);
    557                     stn_le_p(p, width, current & value);
    558                 }
    559                 pflash_update(pfl, offset, width);
    560             }
    561             /*
    562              * While programming, status bit DQ7 should hold the opposite
    563              * value from how it was programmed.
    564              */
    565             set_dq7(pfl, ~value);
    566             /* Let's pretend write is immediate */
    567             if (pfl->bypass)
    568                 goto do_bypass;
    569             goto reset_flash;
    570         case 0x90: /* Autoselect */
    571             if (pfl->bypass && cmd == 0x00) {
    572                 /* Unlock bypass reset */
    573                 goto reset_flash;
    574             }
    575             /*
    576              * We can enter CFI query mode from autoselect mode, but we must
    577              * return to autoselect mode after a reset.
    578              */
    579             if (boff == 0x55 && cmd == 0x98) {
    580                 /* Enter autoselect CFI query mode */
    581                 pfl->wcycle = WCYCLE_AUTOSELECT_CFI;
    582                 pfl->cmd = 0x98;
    583                 return;
    584             }
    585             /* fall through */
    586         default:
    587             trace_pflash_write_invalid(pfl->name, pfl->cmd);
    588             goto reset_flash;
    589         }
    590     case 4:
    591         switch (pfl->cmd) {
    592         case 0xA0: /* Program */
    593             /* Ignore writes while flash data write is occurring */
    594             /* As we suppose write is immediate, this should never happen */
    595             return;
    596         case 0x80: /* Erase */
    597             goto check_unlock1;
    598         default:
    599             /* Should never happen */
    600             trace_pflash_write_invalid_state(pfl->name, pfl->cmd, 5);
    601             goto reset_flash;
    602         }
    603         break;
    604     case 5:
    605         if (pflash_erase_suspend_mode(pfl)) {
    606             /* Erasing is not supported in erase suspend mode. */
    607             goto reset_flash;
    608         }
    609         switch (cmd) {
    610         case 0x10: /* Chip Erase */
    611             if (boff != pfl->unlock_addr0) {
    612                 trace_pflash_chip_erase_invalid(pfl->name, offset);
    613                 goto reset_flash;
    614             }
    615             /* Chip erase */
    616             trace_pflash_chip_erase_start(pfl->name);
    617             if (!pfl->ro) {
    618                 memset(pfl->storage, 0xff, pfl->chip_len);
    619                 pflash_update(pfl, 0, pfl->chip_len);
    620             }
    621             set_dq7(pfl, 0x00);
    622             /* Wait the time specified at CFI address 0x22. */
    623             timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
    624                       (1ULL << pfl->cfi_table[0x22]) * SCALE_MS);
    625             break;
    626         case 0x30: /* Sector erase */
    627             pflash_sector_erase(pfl, offset);
    628             break;
    629         default:
    630             trace_pflash_write_invalid_command(pfl->name, cmd);
    631             goto reset_flash;
    632         }
    633         pfl->cmd = cmd;
    634         break;
    635     case 6:
    636         switch (pfl->cmd) {
    637         case 0x10: /* Chip Erase */
    638             /* Ignore writes during chip erase */
    639             return;
    640         case 0x30: /* Sector erase */
    641             if (cmd == 0xB0) {
    642                 /*
    643                  * If erase suspend happens during the erase timeout (so DQ3 is
    644                  * 0), then the device suspends erasing immediately. Set the
    645                  * remaining time to be the total time to erase. Otherwise,
    646                  * there is a maximum amount of time it can take to enter
    647                  * suspend mode. Let's ignore that and suspend immediately and
    648                  * set the remaining time to the actual time remaining on the
    649                  * timer.
    650                  */
    651                 if ((pfl->status & 0x08) == 0) {
    652                     pfl->erase_time_remaining = pflash_erase_time(pfl);
    653                 } else {
    654                     int64_t delta = timer_expire_time_ns(&pfl->timer) -
    655                         qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
    656                     /* Make sure we have a positive time remaining. */
    657                     pfl->erase_time_remaining = delta <= 0 ? 1 : delta;
    658                 }
    659                 reset_dq3(pfl);
    660                 timer_del(&pfl->timer);
    661                 pflash_reset_state_machine(pfl);
    662                 return;
    663             }
    664             /*
    665              * If DQ3 is 0, additional sector erase commands can be
    666              * written and anything else (other than an erase suspend) resets
    667              * the device.
    668              */
    669             if ((pfl->status & 0x08) == 0) {
    670                 if (cmd == 0x30) {
    671                     pflash_sector_erase(pfl, offset);
    672                 } else {
    673                     goto reset_flash;
    674                 }
    675             }
    676             /* Ignore writes during the actual erase. */
    677             return;
    678         default:
    679             /* Should never happen */
    680             trace_pflash_write_invalid_state(pfl->name, pfl->cmd, 6);
    681             goto reset_flash;
    682         }
    683         break;
    684     /* Special values for CFI queries */
    685     case WCYCLE_CFI:
    686     case WCYCLE_AUTOSELECT_CFI:
    687         trace_pflash_write(pfl->name, "invalid write in CFI query mode");
    688         goto reset_flash;
    689     default:
    690         /* Should never happen */
    691         trace_pflash_write(pfl->name, "invalid write state (wc 7)");
    692         goto reset_flash;
    693     }
    694     pfl->wcycle++;
    695 
    696     return;
    697 
    698     /* Reset flash */
    699  reset_flash:
    700     pfl->bypass = 0;
    701     pflash_reset_state_machine(pfl);
    702     return;
    703 
    704  do_bypass:
    705     pfl->wcycle = 2;
    706     pfl->cmd = 0;
    707 }
    708 
    709 static const MemoryRegionOps pflash_cfi02_ops = {
    710     .read = pflash_read,
    711     .write = pflash_write,
    712     .valid.min_access_size = 1,
    713     .valid.max_access_size = 4,
    714     .endianness = DEVICE_NATIVE_ENDIAN,
    715 };
    716 
    717 static void pflash_cfi02_fill_cfi_table(PFlashCFI02 *pfl, int nb_regions)
    718 {
    719     /* Hardcoded CFI table (mostly from SG29 Spansion flash) */
    720     const uint16_t pri_ofs = 0x40;
    721     /* Standard "QRY" string */
    722     pfl->cfi_table[0x10] = 'Q';
    723     pfl->cfi_table[0x11] = 'R';
    724     pfl->cfi_table[0x12] = 'Y';
    725     /* Command set (AMD/Fujitsu) */
    726     pfl->cfi_table[0x13] = 0x02;
    727     pfl->cfi_table[0x14] = 0x00;
    728     /* Primary extended table address */
    729     pfl->cfi_table[0x15] = pri_ofs;
    730     pfl->cfi_table[0x16] = pri_ofs >> 8;
    731     /* Alternate command set (none) */
    732     pfl->cfi_table[0x17] = 0x00;
    733     pfl->cfi_table[0x18] = 0x00;
    734     /* Alternate extended table (none) */
    735     pfl->cfi_table[0x19] = 0x00;
    736     pfl->cfi_table[0x1A] = 0x00;
    737     /* Vcc min */
    738     pfl->cfi_table[0x1B] = 0x27;
    739     /* Vcc max */
    740     pfl->cfi_table[0x1C] = 0x36;
    741     /* Vpp min (no Vpp pin) */
    742     pfl->cfi_table[0x1D] = 0x00;
    743     /* Vpp max (no Vpp pin) */
    744     pfl->cfi_table[0x1E] = 0x00;
    745     /* Timeout per single byte/word write (128 ms) */
    746     pfl->cfi_table[0x1F] = 0x07;
    747     /* Timeout for min size buffer write (NA) */
    748     pfl->cfi_table[0x20] = 0x00;
    749     /* Typical timeout for block erase (512 ms) */
    750     pfl->cfi_table[0x21] = 0x09;
    751     /* Typical timeout for full chip erase (4096 ms) */
    752     pfl->cfi_table[0x22] = 0x0C;
    753     /* Reserved */
    754     pfl->cfi_table[0x23] = 0x01;
    755     /* Max timeout for buffer write (NA) */
    756     pfl->cfi_table[0x24] = 0x00;
    757     /* Max timeout for block erase */
    758     pfl->cfi_table[0x25] = 0x0A;
    759     /* Max timeout for chip erase */
    760     pfl->cfi_table[0x26] = 0x0D;
    761     /* Device size */
    762     pfl->cfi_table[0x27] = ctz32(pfl->chip_len);
    763     /* Flash device interface (8 & 16 bits) */
    764     pfl->cfi_table[0x28] = 0x02;
    765     pfl->cfi_table[0x29] = 0x00;
    766     /* Max number of bytes in multi-bytes write */
    767     /*
    768      * XXX: disable buffered write as it's not supported
    769      * pfl->cfi_table[0x2A] = 0x05;
    770      */
    771     pfl->cfi_table[0x2A] = 0x00;
    772     pfl->cfi_table[0x2B] = 0x00;
    773     /* Number of erase block regions */
    774     pfl->cfi_table[0x2c] = nb_regions;
    775     /* Erase block regions */
    776     for (int i = 0; i < nb_regions; ++i) {
    777         uint32_t sector_len_per_device = pfl->sector_len[i];
    778         pfl->cfi_table[0x2d + 4 * i] = pfl->nb_blocs[i] - 1;
    779         pfl->cfi_table[0x2e + 4 * i] = (pfl->nb_blocs[i] - 1) >> 8;
    780         pfl->cfi_table[0x2f + 4 * i] = sector_len_per_device >> 8;
    781         pfl->cfi_table[0x30 + 4 * i] = sector_len_per_device >> 16;
    782     }
    783     assert(0x2c + 4 * nb_regions < pri_ofs);
    784 
    785     /* Extended */
    786     pfl->cfi_table[0x00 + pri_ofs] = 'P';
    787     pfl->cfi_table[0x01 + pri_ofs] = 'R';
    788     pfl->cfi_table[0x02 + pri_ofs] = 'I';
    789 
    790     /* Extended version 1.0 */
    791     pfl->cfi_table[0x03 + pri_ofs] = '1';
    792     pfl->cfi_table[0x04 + pri_ofs] = '0';
    793 
    794     /* Address sensitive unlock required. */
    795     pfl->cfi_table[0x05 + pri_ofs] = 0x00;
    796     /* Erase suspend to read/write. */
    797     pfl->cfi_table[0x06 + pri_ofs] = 0x02;
    798     /* Sector protect not supported. */
    799     pfl->cfi_table[0x07 + pri_ofs] = 0x00;
    800     /* Temporary sector unprotect not supported. */
    801     pfl->cfi_table[0x08 + pri_ofs] = 0x00;
    802 
    803     /* Sector protect/unprotect scheme. */
    804     pfl->cfi_table[0x09 + pri_ofs] = 0x00;
    805 
    806     /* Simultaneous operation not supported. */
    807     pfl->cfi_table[0x0a + pri_ofs] = 0x00;
    808     /* Burst mode not supported. */
    809     pfl->cfi_table[0x0b + pri_ofs] = 0x00;
    810     /* Page mode not supported. */
    811     pfl->cfi_table[0x0c + pri_ofs] = 0x00;
    812     assert(0x0c + pri_ofs < ARRAY_SIZE(pfl->cfi_table));
    813 }
    814 
    815 static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
    816 {
    817     ERRP_GUARD();
    818     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
    819     int ret;
    820 
    821     if (pfl->uniform_sector_len == 0 && pfl->sector_len[0] == 0) {
    822         error_setg(errp, "attribute \"sector-length\" not specified or zero.");
    823         return;
    824     }
    825     if (pfl->uniform_nb_blocs == 0 && pfl->nb_blocs[0] == 0) {
    826         error_setg(errp, "attribute \"num-blocks\" not specified or zero.");
    827         return;
    828     }
    829     if (pfl->name == NULL) {
    830         error_setg(errp, "attribute \"name\" not specified.");
    831         return;
    832     }
    833 
    834     int nb_regions;
    835     pfl->chip_len = 0;
    836     pfl->total_sectors = 0;
    837     for (nb_regions = 0; nb_regions < PFLASH_MAX_ERASE_REGIONS; ++nb_regions) {
    838         if (pfl->nb_blocs[nb_regions] == 0) {
    839             break;
    840         }
    841         pfl->total_sectors += pfl->nb_blocs[nb_regions];
    842         uint64_t sector_len_per_device = pfl->sector_len[nb_regions];
    843 
    844         /*
    845          * The size of each flash sector must be a power of 2 and it must be
    846          * aligned at the same power of 2.
    847          */
    848         if (sector_len_per_device & 0xff ||
    849             sector_len_per_device >= (1 << 24) ||
    850             !is_power_of_2(sector_len_per_device))
    851         {
    852             error_setg(errp, "unsupported configuration: "
    853                        "sector length[%d] per device = %" PRIx64 ".",
    854                        nb_regions, sector_len_per_device);
    855             return;
    856         }
    857         if (pfl->chip_len & (sector_len_per_device - 1)) {
    858             error_setg(errp, "unsupported configuration: "
    859                        "flash region %d not correctly aligned.",
    860                        nb_regions);
    861             return;
    862         }
    863 
    864         pfl->chip_len += (uint64_t)pfl->sector_len[nb_regions] *
    865                           pfl->nb_blocs[nb_regions];
    866     }
    867 
    868     uint64_t uniform_len = (uint64_t)pfl->uniform_nb_blocs *
    869                            pfl->uniform_sector_len;
    870     if (nb_regions == 0) {
    871         nb_regions = 1;
    872         pfl->nb_blocs[0] = pfl->uniform_nb_blocs;
    873         pfl->sector_len[0] = pfl->uniform_sector_len;
    874         pfl->chip_len = uniform_len;
    875         pfl->total_sectors = pfl->uniform_nb_blocs;
    876     } else if (uniform_len != 0 && uniform_len != pfl->chip_len) {
    877         error_setg(errp, "\"num-blocks\"*\"sector-length\" "
    878                    "different from \"num-blocks0\"*\'sector-length0\" + ... + "
    879                    "\"num-blocks3\"*\"sector-length3\"");
    880         return;
    881     }
    882 
    883     memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
    884                                   &pflash_cfi02_ops, pfl, pfl->name,
    885                                   pfl->chip_len, errp);
    886     if (*errp) {
    887         return;
    888     }
    889 
    890     pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem);
    891 
    892     if (pfl->blk) {
    893         uint64_t perm;
    894         pfl->ro = !blk_supports_write_perm(pfl->blk);
    895         perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE);
    896         ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp);
    897         if (ret < 0) {
    898             return;
    899         }
    900     } else {
    901         pfl->ro = 0;
    902     }
    903 
    904     if (pfl->blk) {
    905         if (!blk_check_size_and_read_all(pfl->blk, pfl->storage,
    906                                          pfl->chip_len, errp)) {
    907             vmstate_unregister_ram(&pfl->orig_mem, DEVICE(pfl));
    908             return;
    909         }
    910     }
    911 
    912     /* Only 11 bits are used in the comparison. */
    913     pfl->unlock_addr0 &= 0x7FF;
    914     pfl->unlock_addr1 &= 0x7FF;
    915 
    916     /* Allocate memory for a bitmap for sectors being erased. */
    917     pfl->sector_erase_map = bitmap_new(pfl->total_sectors);
    918 
    919     pfl->rom_mode = true;
    920     if (pfl->mappings > 1) {
    921         pflash_setup_mappings(pfl);
    922         sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem);
    923     } else {
    924         sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->orig_mem);
    925     }
    926 
    927     timer_init_ns(&pfl->timer, QEMU_CLOCK_VIRTUAL, pflash_timer, pfl);
    928     pfl->status = 0;
    929 
    930     pflash_cfi02_fill_cfi_table(pfl, nb_regions);
    931 }
    932 
    933 static void pflash_cfi02_reset(DeviceState *dev)
    934 {
    935     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
    936 
    937     pflash_reset_state_machine(pfl);
    938 }
    939 
    940 static Property pflash_cfi02_properties[] = {
    941     DEFINE_PROP_DRIVE("drive", PFlashCFI02, blk),
    942     DEFINE_PROP_UINT32("num-blocks", PFlashCFI02, uniform_nb_blocs, 0),
    943     DEFINE_PROP_UINT32("sector-length", PFlashCFI02, uniform_sector_len, 0),
    944     DEFINE_PROP_UINT32("num-blocks0", PFlashCFI02, nb_blocs[0], 0),
    945     DEFINE_PROP_UINT32("sector-length0", PFlashCFI02, sector_len[0], 0),
    946     DEFINE_PROP_UINT32("num-blocks1", PFlashCFI02, nb_blocs[1], 0),
    947     DEFINE_PROP_UINT32("sector-length1", PFlashCFI02, sector_len[1], 0),
    948     DEFINE_PROP_UINT32("num-blocks2", PFlashCFI02, nb_blocs[2], 0),
    949     DEFINE_PROP_UINT32("sector-length2", PFlashCFI02, sector_len[2], 0),
    950     DEFINE_PROP_UINT32("num-blocks3", PFlashCFI02, nb_blocs[3], 0),
    951     DEFINE_PROP_UINT32("sector-length3", PFlashCFI02, sector_len[3], 0),
    952     DEFINE_PROP_UINT8("width", PFlashCFI02, width, 0),
    953     DEFINE_PROP_UINT8("mappings", PFlashCFI02, mappings, 0),
    954     DEFINE_PROP_UINT8("big-endian", PFlashCFI02, be, 0),
    955     DEFINE_PROP_UINT16("id0", PFlashCFI02, ident0, 0),
    956     DEFINE_PROP_UINT16("id1", PFlashCFI02, ident1, 0),
    957     DEFINE_PROP_UINT16("id2", PFlashCFI02, ident2, 0),
    958     DEFINE_PROP_UINT16("id3", PFlashCFI02, ident3, 0),
    959     DEFINE_PROP_UINT16("unlock-addr0", PFlashCFI02, unlock_addr0, 0),
    960     DEFINE_PROP_UINT16("unlock-addr1", PFlashCFI02, unlock_addr1, 0),
    961     DEFINE_PROP_STRING("name", PFlashCFI02, name),
    962     DEFINE_PROP_END_OF_LIST(),
    963 };
    964 
    965 static void pflash_cfi02_unrealize(DeviceState *dev)
    966 {
    967     PFlashCFI02 *pfl = PFLASH_CFI02(dev);
    968     timer_del(&pfl->timer);
    969     g_free(pfl->sector_erase_map);
    970 }
    971 
    972 static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
    973 {
    974     DeviceClass *dc = DEVICE_CLASS(klass);
    975 
    976     dc->realize = pflash_cfi02_realize;
    977     dc->reset = pflash_cfi02_reset;
    978     dc->unrealize = pflash_cfi02_unrealize;
    979     device_class_set_props(dc, pflash_cfi02_properties);
    980     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
    981 }
    982 
    983 static const TypeInfo pflash_cfi02_info = {
    984     .name           = TYPE_PFLASH_CFI02,
    985     .parent         = TYPE_SYS_BUS_DEVICE,
    986     .instance_size  = sizeof(PFlashCFI02),
    987     .class_init     = pflash_cfi02_class_init,
    988 };
    989 
    990 static void pflash_cfi02_register_types(void)
    991 {
    992     type_register_static(&pflash_cfi02_info);
    993 }
    994 
    995 type_init(pflash_cfi02_register_types)
    996 
    997 PFlashCFI02 *pflash_cfi02_register(hwaddr base,
    998                                    const char *name,
    999                                    hwaddr size,
   1000                                    BlockBackend *blk,
   1001                                    uint32_t sector_len,
   1002                                    int nb_mappings, int width,
   1003                                    uint16_t id0, uint16_t id1,
   1004                                    uint16_t id2, uint16_t id3,
   1005                                    uint16_t unlock_addr0,
   1006                                    uint16_t unlock_addr1,
   1007                                    int be)
   1008 {
   1009     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI02);
   1010 
   1011     if (blk) {
   1012         qdev_prop_set_drive(dev, "drive", blk);
   1013     }
   1014     assert(QEMU_IS_ALIGNED(size, sector_len));
   1015     qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
   1016     qdev_prop_set_uint32(dev, "sector-length", sector_len);
   1017     qdev_prop_set_uint8(dev, "width", width);
   1018     qdev_prop_set_uint8(dev, "mappings", nb_mappings);
   1019     qdev_prop_set_uint8(dev, "big-endian", !!be);
   1020     qdev_prop_set_uint16(dev, "id0", id0);
   1021     qdev_prop_set_uint16(dev, "id1", id1);
   1022     qdev_prop_set_uint16(dev, "id2", id2);
   1023     qdev_prop_set_uint16(dev, "id3", id3);
   1024     qdev_prop_set_uint16(dev, "unlock-addr0", unlock_addr0);
   1025     qdev_prop_set_uint16(dev, "unlock-addr1", unlock_addr1);
   1026     qdev_prop_set_string(dev, "name", name);
   1027     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
   1028 
   1029     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
   1030     return PFLASH_CFI02(dev);
   1031 }