/*
* CFI parallel flash with AMD command set emulation
*
* Copyright (c) 2005 Jocelyn Mayer
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
* For now, this code can emulate flashes of 1, 2 or 4 bytes width.
* Supported commands/modes are:
* - flash read
* - flash write
* - flash ID read
* - sector erase
* - chip erase
* - unlock bypass command
* - CFI queries
*
* It does not support flash interleaving.
* It does not implement boot blocs with reduced size
* It does not implement software data protection as found in many real chips
* It does not implement erase suspend/resume commands
* It does not implement multiple sectors erase
*/
#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/block/block.h"
#include "hw/block/flash.h"
#include "qapi/error.h"
#include "qemu/timer.h"
#include "sysemu/block-backend.h"
#include "qemu/host-utils.h"
#include "qemu/module.h"
#include "hw/sysbus.h"
#include "trace.h"
#define PFLASH_DEBUG false
#define DPRINTF(fmt, ...) \
do { \
if (PFLASH_DEBUG) { \
fprintf(stderr, "PFLASH: " fmt, ## __VA_ARGS__); \
} \
} while (0)
#define PFLASH_LAZY_ROMD_THRESHOLD 42
/* Special write cycles for CFI queries. */
enum {
WCYCLE_CFI = 7,
};
struct PFlashCFI02 {
/*< private >*/
SysBusDevice parent_obj;
/*< public >*/
BlockBackend *blk;
uint32_t sector_len;
uint32_t nb_blocs;
uint32_t chip_len;
uint8_t mappings;
uint8_t width;
uint8_t be;
int wcycle; /* if 0, the flash is read normally */
int bypass;
int ro;
uint8_t cmd;
uint8_t status;
/* FIXME: implement array device properties */
uint16_t ident0;
uint16_t ident1;
uint16_t ident2;
uint16_t ident3;
uint16_t unlock_addr0;
uint16_t unlock_addr1;
uint8_t cfi_table[0x52];
QEMUTimer timer;
/* The device replicates the flash memory across its memory space. Emulate
* that by having a container (.mem) filled with an array of aliases
* (.mem_mappings) pointing to the flash memory (.orig_mem).
*/
MemoryRegion mem;
MemoryRegion *mem_mappings; /* array; one per mapping */
MemoryRegion orig_mem;
int rom_mode;
int read_counter; /* used for lazy switch-back to rom mode */
char *name;
void *storage;
};
/*
* Toggle status bit DQ7.
*/
static inline void toggle_dq7(PFlashCFI02 *pfl)
{
pfl->status ^= 0x80;
}
/*
* Set status bit DQ7 to bit 7 of value.
*/
static inline void set_dq7(PFlashCFI02 *pfl, uint8_t value)
{
pfl->status &= 0x7F;
pfl->status |= value & 0x80;
}
/*
* Toggle status bit DQ6.
*/
static inline void toggle_dq6(PFlashCFI02 *pfl)
{
pfl->status ^= 0x40;
}
/*
* Set up replicated mappings of the same region.
*/
static void pflash_setup_mappings(PFlashCFI02 *pfl)
{
unsigned i;
hwaddr size = memory_region_size(&pfl->orig_mem);
memory_region_init(&pfl->mem, OBJECT(pfl), "pflash", pfl->mappings * size);
pfl->mem_mappings = g_new(MemoryRegion, pfl->mappings);
for (i = 0; i < pfl->mappings; ++i) {
memory_region_init_alias(&pfl->mem_mappings[i], OBJECT(pfl),
"pflash-alias", &pfl->orig_mem, 0, size);
memory_region_add_subregion(&pfl->mem, i * size, &pfl->mem_mappings[i]);
}
}
static void pflash_register_memory(PFlashCFI02 *pfl, int rom_mode)
{
memory_region_rom_device_set_romd(&pfl->orig_mem, rom_mode);
pfl->rom_mode = rom_mode;
}
static void pflash_timer (void *opaque)
{
PFlashCFI02 *pfl = opaque;
trace_pflash_timer_expired(pfl->cmd);
/* Reset flash */
toggle_dq7(pfl);
if (pfl->bypass) {
pfl->wcycle = 2;
} else {
pflash_register_memory(pfl, 1);
pfl->wcycle = 0;
}
pfl->cmd = 0;
}
/*
* Read data from flash.
*/
static uint64_t pflash_data_read(PFlashCFI02 *pfl, hwaddr offset,
unsigned int width)
{
uint8_t *p = (uint8_t *)pfl->storage + offset;
uint64_t ret = pfl->be ? ldn_be_p(p, width) : ldn_le_p(p, width);
trace_pflash_data_read(offset, width << 1, ret);
return ret;
}
static uint64_t pflash_read(void *opaque, hwaddr offset, unsigned int width)
{
PFlashCFI02 *pfl = opaque;
hwaddr boff;
uint64_t ret;
ret = -1;
/* Lazy reset to ROMD mode after a certain amount of read accesses */
if (!pfl->rom_mode && pfl->wcycle == 0 &&
++pfl->read_counter > PFLASH_LAZY_ROMD_THRESHOLD) {
pflash_register_memory(pfl, 1);
}
offset &= pfl->chip_len - 1;
boff = offset & 0xFF;
if (pfl->width == 2)
boff = boff >> 1;
else if (pfl->width == 4)
boff = boff >> 2;
switch (pfl->cmd) {
default:
/* This should never happen : reset state & treat it as a read*/
DPRINTF("%s: unknown command state: %x\n", __func__, pfl->cmd);
pfl->wcycle = 0;
pfl->cmd = 0;
/* fall through to the read code */
case 0x80:
/* We accept reads during second unlock sequence... */
case 0x00:
/* Flash area read */
ret = pflash_data_read(pfl, offset, width);
break;
case 0x90:
/* flash ID read */
switch (boff) {
case 0x00:
case 0x01:
ret = boff & 0x01 ? pfl->ident1 : pfl->ident0;
break;
case 0x02:
ret = 0x00; /* Pretend all sectors are unprotected */
break;
case 0x0E:
case 0x0F:
ret = boff & 0x01 ? pfl->ident3 : pfl->ident2;
if (ret != (uint8_t)-1) {
break;
}
/* Fall through to data read. */
default:
ret = pflash_data_read(pfl, offset, width);
}
DPRINTF("%s: ID " TARGET_FMT_plx " %" PRIx64 "\n", __func__, boff, ret);
break;
case 0xA0:
case 0x10:
case 0x30:
/* Status register read */
ret = pfl->status;
DPRINTF("%s: status %" PRIx64 "\n", __func__, ret);
toggle_dq6(pfl);
break;
case 0x98:
/* CFI query mode */
if (boff < sizeof(pfl->cfi_table)) {
ret = pfl->cfi_table[boff];
} else {
ret = 0;
}
break;
}
trace_pflash_io_read(offset, width, width << 1, ret, pfl->cmd, pfl->wcycle);
return ret;
}
/* update flash content on disk */
static void pflash_update(PFlashCFI02 *pfl, int offset, int size)
{
int offset_end;
if (pfl->blk) {
offset_end = offset + size;
/* widen to sector boundaries */
offset = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
offset_end = QEMU_ALIGN_UP(offset_end, BDRV_SECTOR_SIZE);
blk_pwrite(pfl->blk, offset, pfl->storage + offset,
offset_end - offset, 0);
}
}
static void pflash_write(void *opaque, hwaddr offset, uint64_t value,
unsigned int width)
{
PFlashCFI02 *pfl = opaque;
hwaddr boff;
uint8_t *p;
uint8_t cmd;
trace_pflash_io_write(offset, width, width << 1, value, pfl->wcycle);
cmd = value;
if (pfl->cmd != 0xA0 && cmd == 0xF0) {
goto reset_flash;
}
offset &= pfl->chip_len - 1;
boff = offset;
if (pfl->width == 2)
boff = boff >> 1;
else if (pfl->width == 4)
boff = boff >> 2;
/* Only the least-significant 11 bits are used in most cases. */
boff &= 0x7FF;
switch (pfl->wcycle) {
case 0:
/* Set the device in I/O access mode if required */
if (pfl->rom_mode)
pflash_register_memory(pfl, 0);
pfl->read_counter = 0;
/* We're in read mode */
check_unlock0:
if (boff == 0x55 && cmd == 0x98) {
enter_CFI_mode:
/* Enter CFI query mode */
pfl->wcycle = WCYCLE_CFI;
pfl->cmd = 0x98;
return;
}
if (boff != pfl->unlock_addr0 || cmd != 0xAA) {
DPRINTF("%s: unlock0 failed " TARGET_FMT_plx " %02x %04x\n",
__func__, boff, cmd, pfl->unlock_addr0);
goto reset_flash;
}
DPRINTF("%s: unlock sequence started\n", __func__);
break;
case 1:
/* We started an unlock sequence */
check_unlock1:
if (boff != pfl->unlock_addr1 || cmd != 0x55) {
DPRINTF("%s: unlock1 failed " TARGET_FMT_plx " %02x\n", __func__,
boff, cmd);
goto reset_flash;
}
DPRINTF("%s: unlock sequence done\n", __func__);
break;
case 2:
/* We finished an unlock sequence */
if (!pfl->bypass && boff != pfl->unlock_addr0) {
DPRINTF("%s: command failed " TARGET_FMT_plx " %02x\n", __func__,
boff, cmd);
goto reset_flash;
}
switch (cmd) {
case 0x20:
pfl->bypass = 1;
goto do_bypass;
case 0x80:
case 0x90:
case 0xA0:
pfl->cmd = cmd;
DPRINTF("%s: starting command %02x\n", __func__, cmd);
break;
default:
DPRINTF("%s: unknown command %02x\n", __func__, cmd);
goto reset_flash;
}
break;
case 3:
switch (pfl->cmd) {
case 0x80:
/* We need another unlock sequence */
goto check_unlock0;
case 0xA0:
trace_pflash_data_write(offset, width << 1, value, 0);
if (!pfl->ro) {
p = (uint8_t *)pfl->storage + offset;
if (pfl->be) {
uint64_t current = ldn_be_p(p, width);
stn_be_p(p, width, current & value);
} else {
uint64_t current = ldn_le_p(p, width);
stn_le_p(p, width, current & value);
}
pflash_update(pfl, offset, width);
}
/*
* While programming, status bit DQ7 should hold the opposite
* value from how it was programmed.
*/
set_dq7(pfl, ~value);
/* Let's pretend write is immediate */
if (pfl->bypass)
goto do_bypass;
goto reset_flash;
case 0x90:
if (pfl->bypass && cmd == 0x00) {
/* Unlock bypass reset */
goto reset_flash;
}
/* We can enter CFI query mode from autoselect mode */
if (boff == 0x55 && cmd == 0x98)
goto enter_CFI_mode;
/* No break here */
default:
DPRINTF("%s: invalid write for command %02x\n",
__func__, pfl->cmd);
goto reset_flash;
}
case 4:
switch (pfl->cmd) {
case 0xA0:
/* Ignore writes while flash data write is occurring */
/* As we suppose write is immediate, this should never happen */
return;
case 0x80:
goto check_unlock1;
default:
/* Should never happen */
DPRINTF("%s: invalid command state %02x (wc 4)\n",
__func__, pfl->cmd);
goto reset_flash;
}
break;
case 5:
switch (cmd) {
case 0x10:
if (boff != pfl->unlock_addr0) {
DPRINTF("%s: chip erase: invalid address " TARGET_FMT_plx "\n",
__func__, offset);
goto reset_flash;
}
/* Chip erase */
DPRINTF("%s: start chip erase\n", __func__);
if (!pfl->ro) {
memset(pfl->storage, 0xff, pfl->chip_len);
pflash_update(pfl, 0, pfl->chip_len);
}
set_dq7(pfl, 0x00);
/* Let's wait 5 seconds before chip erase is done */
timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
(NANOSECONDS_PER_SECOND * 5));
break;
case 0x30:
/* Sector erase */
p = pfl->storage;
offset &= ~(pfl->sector_len - 1);
DPRINTF("%s: start sector erase at " TARGET_FMT_plx "\n", __func__,
offset);
if (!pfl->ro) {
memset(p + offset, 0xFF, pfl->sector_len);
pflash_update(pfl, offset, pfl->sector_len);
}
set_dq7(pfl, 0x00);
/* Let's wait 1/2 second before sector erase is done */
timer_mod(&pfl->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
(NANOSECONDS_PER_SECOND / 2));
break;
default:
DPRINTF("%s: invalid command %02x (wc 5)\n", __func__, cmd);
goto reset_flash;
}
pfl->cmd = cmd;
break;
case 6:
switch (pfl->cmd) {
case 0x10:
/* Ignore writes during chip erase */
return;
case 0x30:
/* Ignore writes during sector erase */
return;
default:
/* Should never happen */
DPRINTF("%s: invalid command state %02x (wc 6)\n",
__func__, pfl->cmd);
goto reset_flash;
}
break;
/* Special values for CFI queries */
case WCYCLE_CFI:
DPRINTF("%s: invalid write in CFI query mode\n", __func__);
goto reset_flash;
default:
/* Should never happen */
DPRINTF("%s: invalid write state (wc 7)\n", __func__);
goto reset_flash;
}
pfl->wcycle++;
return;
/* Reset flash */
reset_flash:
trace_pflash_reset();
pfl->bypass = 0;
pfl->wcycle = 0;
pfl->cmd = 0;
return;
do_bypass:
pfl->wcycle = 2;
pfl->cmd = 0;
}
static const MemoryRegionOps pflash_cfi02_ops = {
.read = pflash_read,
.write = pflash_write,
.valid.min_access_size = 1,
.valid.max_access_size = 4,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
{
PFlashCFI02 *pfl = PFLASH_CFI02(dev);
int ret;
Error *local_err = NULL;
if (pfl->sector_len == 0) {
error_setg(errp, "attribute \"sector-length\" not specified or zero.");
return;
}
if (pfl->nb_blocs == 0) {
error_setg(errp, "attribute \"num-blocks\" not specified or zero.");
return;
}
if (pfl->name == NULL) {
error_setg(errp, "attribute \"name\" not specified.");
return;
}
pfl->chip_len = pfl->sector_len * pfl->nb_blocs;
memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
&pflash_cfi02_ops, pfl, pfl->name,
pfl->chip_len, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem);
if (pfl->blk) {
uint64_t perm;
pfl->ro = blk_is_read_only(pfl->blk);
perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE);
ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp);
if (ret < 0) {
return;
}
} else {
pfl->ro = 0;
}
if (pfl->blk) {
if (!blk_check_size_and_read_all(pfl->blk, pfl->storage,
pfl->chip_len, errp)) {
vmstate_unregister_ram(&pfl->orig_mem, DEVICE(pfl));
return;
}
}
/* Only 11 bits are used in the comparison. */
pfl->unlock_addr0 &= 0x7FF;
pfl->unlock_addr1 &= 0x7FF;
pflash_setup_mappings(pfl);
pfl->rom_mode = 1;
sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem);
timer_init_ns(&pfl->timer, QEMU_CLOCK_VIRTUAL, pflash_timer, pfl);
pfl->wcycle = 0;
pfl->cmd = 0;
pfl->status = 0;
/* Hardcoded CFI table (mostly from SG29 Spansion flash) */
/* Standard "QRY" string */
pfl->cfi_table[0x10] = 'Q';
pfl->cfi_table[0x11] = 'R';
pfl->cfi_table[0x12] = 'Y';
/* Command set (AMD/Fujitsu) */
pfl->cfi_table[0x13] = 0x02;
pfl->cfi_table[0x14] = 0x00;
/* Primary extended table address */
pfl->cfi_table[0x15] = 0x31;
pfl->cfi_table[0x16] = 0x00;
/* Alternate command set (none) */
pfl->cfi_table[0x17] = 0x00;
pfl->cfi_table[0x18] = 0x00;
/* Alternate extended table (none) */
pfl->cfi_table[0x19] = 0x00;
pfl->cfi_table[0x1A] = 0x00;
/* Vcc min */
pfl->cfi_table[0x1B] = 0x27;
/* Vcc max */
pfl->cfi_table[0x1C] = 0x36;
/* Vpp min (no Vpp pin) */
pfl->cfi_table[0x1D] = 0x00;
/* Vpp max (no Vpp pin) */
pfl->cfi_table[0x1E] = 0x00;
/* Timeout per single byte/word write (128 ms) */
pfl->cfi_table[0x1F] = 0x07;
/* Timeout for min size buffer write (NA) */
pfl->cfi_table[0x20] = 0x00;
/* Typical timeout for block erase (512 ms) */
pfl->cfi_table[0x21] = 0x09;
/* Typical timeout for full chip erase (4096 ms) */
pfl->cfi_table[0x22] = 0x0C;
/* Reserved */
pfl->cfi_table[0x23] = 0x01;
/* Max timeout for buffer write (NA) */
pfl->cfi_table[0x24] = 0x00;
/* Max timeout for block erase */
pfl->cfi_table[0x25] = 0x0A;
/* Max timeout for chip erase */
pfl->cfi_table[0x26] = 0x0D;
/* Device size */
pfl->cfi_table[0x27] = ctz32(pfl->chip_len);
/* Flash device interface (8 & 16 bits) */
pfl->cfi_table[0x28] = 0x02;
pfl->cfi_table[0x29] = 0x00;
/* Max number of bytes in multi-bytes write */
/* XXX: disable buffered write as it's not supported */
// pfl->cfi_table[0x2A] = 0x05;
pfl->cfi_table[0x2A] = 0x00;
pfl->cfi_table[0x2B] = 0x00;
/* Number of erase block regions (uniform) */
pfl->cfi_table[0x2C] = 0x01;
/* Erase block region 1 */
pfl->cfi_table[0x2D] = pfl->nb_blocs - 1;
pfl->cfi_table[0x2E] = (pfl->nb_blocs - 1) >> 8;
pfl->cfi_table[0x2F] = pfl->sector_len >> 8;
pfl->cfi_table[0x30] = pfl->sector_len >> 16;
/* Extended */
pfl->cfi_table[0x31] = 'P';
pfl->cfi_table[0x32] = 'R';
pfl->cfi_table[0x33] = 'I';
/* Extended version 1.0 */
pfl->cfi_table[0x34] = '1';
pfl->cfi_table[0x35] = '0';
/* Address sensitive unlock required. */
pfl->cfi_table[0x36] = 0x00;
/* Erase suspend not supported. */
pfl->cfi_table[0x37] = 0x00;
/* Sector protect not supported. */
pfl->cfi_table[0x38] = 0x00;
/* Temporary sector unprotect not supported. */
pfl->cfi_table[0x39] = 0x00;
/* Sector protect/unprotect scheme. */
pfl->cfi_table[0x3a] = 0x00;
/* Simultaneous operation not supported. */
pfl->cfi_table[0x3b] = 0x00;
/* Burst mode not supported. */
pfl->cfi_table[0x3c] = 0x00;
}
static Property pflash_cfi02_properties[] = {
DEFINE_PROP_DRIVE("drive", PFlashCFI02, blk),
DEFINE_PROP_UINT32("num-blocks", PFlashCFI02, nb_blocs, 0),
DEFINE_PROP_UINT32("sector-length", PFlashCFI02, sector_len, 0),
DEFINE_PROP_UINT8("width", PFlashCFI02, width, 0),
DEFINE_PROP_UINT8("mappings", PFlashCFI02, mappings, 0),
DEFINE_PROP_UINT8("big-endian", PFlashCFI02, be, 0),
DEFINE_PROP_UINT16("id0", PFlashCFI02, ident0, 0),
DEFINE_PROP_UINT16("id1", PFlashCFI02, ident1, 0),
DEFINE_PROP_UINT16("id2", PFlashCFI02, ident2, 0),
DEFINE_PROP_UINT16("id3", PFlashCFI02, ident3, 0),
DEFINE_PROP_UINT16("unlock-addr0", PFlashCFI02, unlock_addr0, 0),
DEFINE_PROP_UINT16("unlock-addr1", PFlashCFI02, unlock_addr1, 0),
DEFINE_PROP_STRING("name", PFlashCFI02, name),
DEFINE_PROP_END_OF_LIST(),
};
static void pflash_cfi02_unrealize(DeviceState *dev, Error **errp)
{
PFlashCFI02 *pfl = PFLASH_CFI02(dev);
timer_del(&pfl->timer);
}
static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = pflash_cfi02_realize;
dc->unrealize = pflash_cfi02_unrealize;
dc->props = pflash_cfi02_properties;
set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
}
static const TypeInfo pflash_cfi02_info = {
.name = TYPE_PFLASH_CFI02,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(PFlashCFI02),
.class_init = pflash_cfi02_class_init,
};
static void pflash_cfi02_register_types(void)
{
type_register_static(&pflash_cfi02_info);
}
type_init(pflash_cfi02_register_types)
PFlashCFI02 *pflash_cfi02_register(hwaddr base,
const char *name,
hwaddr size,
BlockBackend *blk,
uint32_t sector_len,
int nb_mappings, int width,
uint16_t id0, uint16_t id1,
uint16_t id2, uint16_t id3,
uint16_t unlock_addr0,
uint16_t unlock_addr1,
int be)
{
DeviceState *dev = qdev_create(NULL, TYPE_PFLASH_CFI02);
if (blk) {
qdev_prop_set_drive(dev, "drive", blk, &error_abort);
}
assert(size % sector_len == 0);
qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
qdev_prop_set_uint32(dev, "sector-length", sector_len);
qdev_prop_set_uint8(dev, "width", width);
qdev_prop_set_uint8(dev, "mappings", nb_mappings);
qdev_prop_set_uint8(dev, "big-endian", !!be);
qdev_prop_set_uint16(dev, "id0", id0);
qdev_prop_set_uint16(dev, "id1", id1);
qdev_prop_set_uint16(dev, "id2", id2);
qdev_prop_set_uint16(dev, "id3", id3);
qdev_prop_set_uint16(dev, "unlock-addr0", unlock_addr0);
qdev_prop_set_uint16(dev, "unlock-addr1", unlock_addr1);
qdev_prop_set_string(dev, "name", name);
qdev_init_nofail(dev);
sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
return PFLASH_CFI02(dev);
}