/*
* Simulate a SPI flash
*
* Copyright (c) 2011-2013 The Chromium OS Authors.
* See file CREDITS for list of people who contributed to this
* project.
*
* Licensed under the GPL-2 or later.
*/
#include <common.h>
#include <dm.h>
#include <malloc.h>
#include <spi.h>
#include <os.h>
#include <spi_flash.h>
#include "sf_internal.h"
#include <asm/getopt.h>
#include <asm/spi.h>
#include <asm/state.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <dm/uclass-internal.h>
/*
* The different states that our SPI flash transitions between.
* We need to keep track of this across multiple xfer calls since
* the SPI bus could possibly call down into us multiple times.
*/
enum sandbox_sf_state {
SF_CMD, /* default state -- we're awaiting a command */
SF_ID, /* read the flash's (jedec) ID code */
SF_ADDR, /* processing the offset in the flash to read/etc... */
SF_READ, /* reading data from the flash */
SF_WRITE, /* writing data to the flash, i.e. page programming */
SF_ERASE, /* erase the flash */
SF_READ_STATUS, /* read the flash's status register */
SF_READ_STATUS1, /* read the flash's status register upper 8 bits*/
SF_WRITE_STATUS, /* write the flash's status register */
};
static const char *sandbox_sf_state_name(enum sandbox_sf_state state)
{
static const char * const states[] = {
"CMD", "ID", "ADDR", "READ", "WRITE", "ERASE", "READ_STATUS",
"READ_STATUS1", "WRITE_STATUS",
};
return states[state];
}
/* Bits for the status register */
#define STAT_WIP (1 << 0)
#define STAT_WEL (1 << 1)
/* Assume all SPI flashes have 3 byte addresses since they do atm */
#define SF_ADDR_LEN 3
#define IDCODE_LEN 3
/* Used to quickly bulk erase backing store */
static u8 sandbox_sf_0xff[0x1000];
/* Internal state data for each SPI flash */
struct sandbox_spi_flash {
unsigned int cs; /* Chip select we are attached to */
/*
* As we receive data over the SPI bus, our flash transitions
* between states. For example, we start off in the SF_CMD
* state where the first byte tells us what operation to perform
* (such as read or write the flash). But the operation itself
* can go through a few states such as first reading in the
* offset in the flash to perform the requested operation.
* Thus "state" stores the exact state that our machine is in
* while "cmd" stores the overall command we're processing.
*/
enum sandbox_sf_state state;
uint cmd;
/* Erase size of current erase command */
uint erase_size;
/* Current position in the flash; used when reading/writing/etc... */
uint off;
/* How many address bytes we've consumed */
uint addr_bytes, pad_addr_bytes;
/* The current flash status (see STAT_XXX defines above) */
u16 status;
/* Data describing the flash we're emulating */
const struct spi_flash_info *data;
/* The file on disk to serv up data from */
int fd;
};
struct sandbox_spi_flash_plat_data {
const char *filename;
const char *device_name;
int bus;
int cs;
};
/**
* This is a very strange probe function. If it has platform data (which may
* have come from the device tree) then this function gets the filename and
* device type from there. Failing that it looks at the command line
* parameter.
*/
static int sandbox_sf_probe(struct udevice *dev)
{
/* spec = idcode:file */
struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
const char *file;
size_t len, idname_len;
const struct spi_flash_info *data;
struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev);
struct sandbox_state *state = state_get_current();
struct udevice *bus = dev->parent;
const char *spec = NULL;
int ret = 0;
int cs = -1;
int i;
debug("%s: bus %d, looking for emul=%p: ", __func__, bus->seq, dev);
if (bus->seq >= 0 && bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS) {
for (i = 0; i < CONFIG_SANDBOX_SPI_MAX_CS; i++) {
if (state->spi[bus->seq][i].emul == dev)
cs = i;
}
}
if (cs == -1) {
printf("Error: Unknown chip select for device '%s'\n",
dev->name);
return -EINVAL;
}
debug("found at cs %d\n", cs);
if (!pdata->filename) {
struct sandbox_state *state = state_get_current();
assert(bus->seq != -1);
if (bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS)
spec = state->spi[bus->seq][cs].spec;
if (!spec) {
debug("%s: No spec found for bus %d, cs %d\n",
__func__, bus->seq, cs);
ret = -ENOENT;
goto error;
}
file = strchr(spec, ':');
if (!file) {
printf("%s: unable to parse file\n", __func__);
ret = -EINVAL;
goto error;
}
idname_len = file - spec;
pdata->filename = file + 1;
pdata->device_name = spec;
++file;
} else {
spec = strchr(pdata->device_name, ',');
if (spec)
spec++;
else
spec = pdata->device_name;
idname_len = strlen(spec);
}
debug("%s: device='%s'\n", __func__, spec);
for (data = spi_flash_ids; data->name; data++) {
len = strlen(data->name);
if (idname_len != len)
continue;
if (!strncasecmp(spec, data->name, len))
break;
}
if (!data->name) {
printf("%s: unknown flash '%*s'\n", __func__, (int)idname_len,
spec);
ret = -EINVAL;
goto error;
}
if (sandbox_sf_0xff[0] == 0x00)
memset(sandbox_sf_0xff, 0xff, sizeof(sandbox_sf_0xff));
sbsf->fd = os_open(pdata->filename, 02);
if (sbsf->fd == -1) {
printf("%s: unable to open file '%s'\n", __func__,
pdata->filename);
ret = -EIO;
goto error;
}
sbsf->data = data;
sbsf->cs = cs;
return 0;
error:
debug("%s: Got error %d\n", __func__, ret);
return ret;
}
static int sandbox_sf_remove(struct udevice *dev)
{
struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
os_close(sbsf->fd);
return 0;
}
static void sandbox_sf_cs_activate(struct udevice *dev)
{
struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
debug("sandbox_sf: CS activated; state is fresh!\n");
/* CS is asserted, so reset state */
sbsf->off = 0;
sbsf->addr_bytes = 0;
sbsf->pad_addr_bytes = 0;
sbsf->state = SF_CMD;
sbsf->cmd = SF_CMD;
}
static void sandbox_sf_cs_deactivate(struct udevice *dev)
{
debug("sandbox_sf: CS deactivated; cmd done processing!\n");
}
/*
* There are times when the data lines are allowed to tristate. What
* is actually sensed on the line depends on the hardware. It could
* always be 0xFF/0x00 (if there are pull ups/downs), or things could
* float and so we'd get garbage back. This func encapsulates that
* scenario so we can worry about the details here.
*/
static void sandbox_spi_tristate(u8 *buf, uint len)
{
/* XXX: make this into a user config option ? */
memset(buf, 0xff, len);
}
/* Figure out what command this stream is telling us to do */
static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx,
u8 *tx)
{
enum sandbox_sf_state oldstate = sbsf->state;
/* We need to output a byte for the cmd byte we just ate */
if (tx)
sandbox_spi_tristate(tx, 1);
sbsf->cmd = rx[0];
switch (sbsf->cmd) {
case CMD_READ_ID:
sbsf->state = SF_ID;
sbsf->cmd = SF_ID;
break;
case CMD_READ_ARRAY_FAST:
sbsf->pad_addr_bytes = 1;
case CMD_READ_ARRAY_SLOW:
case CMD_PAGE_PROGRAM:
sbsf->state = SF_ADDR;
break;
case CMD_WRITE_DISABLE:
debug(" write disabled\n");
sbsf->status &= ~STAT_WEL;
break;
case CMD_READ_STATUS:
sbsf->state = SF_READ_STATUS;
break;
case CMD_READ_STATUS1:
sbsf->state = SF_READ_STATUS1;
break;
case CMD_WRITE_ENABLE:
debug(" write enabled\n");
sbsf->status |= STAT_WEL;
break;
case CMD_WRITE_STATUS:
sbsf->state = SF_WRITE_STATUS;
break;
default: {
int flags = sbsf->data->flags;
/* we only support erase here */
if (sbsf->cmd == CMD_ERASE_CHIP) {
sbsf->erase_size = sbsf->data->sector_size *
sbsf->data->n_sectors;
} else if (sbsf->cmd == CMD_ERASE_4K && (flags & SECT_4K)) {
sbsf->erase_size = 4 << 10;
} else if (sbsf->cmd == CMD_ERASE_64K && !(flags & SECT_4K)) {
sbsf->erase_size = 64 << 10;
} else {
debug(" cmd unknown: %#x\n", sbsf->cmd);
return -EIO;
}
sbsf->state = SF_ADDR;
break;
}
}
if (oldstate != sbsf->state)
debug(" cmd: transition to %s state\n",
sandbox_sf_state_name(sbsf->state));
return 0;
}
int sandbox_erase_part(struct sandbox_spi_flash *sbsf, int size)
{
int todo;
int ret;
while (size > 0) {
todo = min(size, (int)sizeof(sandbox_sf_0xff));
ret = os_write(sbsf->fd, sandbox_sf_0xff, todo);
if (ret != todo)
return ret;
size -= todo;
}
return 0;
}
static int sandbox_sf_xfer(struct udevice *dev, unsigned int bitlen,
const void *rxp, void *txp, unsigned long flags)
{
struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
const uint8_t *rx = rxp;
uint8_t *tx = txp;
uint cnt, pos = 0;
int bytes = bitlen / 8;
int ret;
debug("sandbox_sf: state:%x(%s) bytes:%u\n", sbsf->state,
sandbox_sf_state_name(sbsf->state), bytes);
if ((flags & SPI_XFER_BEGIN))
sandbox_sf_cs_activate(dev);
if (sbsf->state == SF_CMD) {
/* Figure out the initial state */
ret = sandbox_sf_process_cmd(sbsf, rx, tx);
if (ret)
return ret;
++pos;
}
/* Process the remaining data */
while (pos < bytes) {
switch (sbsf->state) {
case SF_ID: {
u8 id;
debug(" id: off:%u tx:", sbsf->off);
if (sbsf->off < IDCODE_LEN) {
/* Extract correct byte from ID 0x00aabbcc */
id = ((JEDEC_MFR(sbsf->data) << 16) |
JEDEC_ID(sbsf->data)) >>
(8 * (IDCODE_LEN - 1 - sbsf->off));
} else {
id = 0;
}
debug("%d %02x\n", sbsf->off, id);
tx[pos++] = id;
++sbsf->off;
break;
}
case SF_ADDR:
debug(" addr: bytes:%u rx:%02x ", sbsf->addr_bytes,
rx[pos]);
if (sbsf->addr_bytes++ < SF_ADDR_LEN)
sbsf->off = (sbsf->off << 8) | rx[pos];
debug("addr:%06x\n", sbsf->off);
if (tx)
sandbox_spi_tristate(&tx[pos], 1);
pos++;
/* See if we're done processing */
if (sbsf->addr_bytes <
SF_ADDR_LEN + sbsf->pad_addr_bytes)
break;
/* Next state! */
if (os_lseek(sbsf->fd, sbsf->off, OS_SEEK_SET) < 0) {
puts("sandbox_sf: os_lseek() failed");
return -EIO;
}
switch (sbsf->cmd) {
case CMD_READ_ARRAY_FAST:
case CMD_READ_ARRAY_SLOW:
sbsf->state = SF_READ;
break;
case CMD_PAGE_PROGRAM:
sbsf->state = SF_WRITE;
break;
default:
/* assume erase state ... */
sbsf->state = SF_ERASE;
goto case_sf_erase;
}
debug(" cmd: transition to %s state\n",
sandbox_sf_state_name(sbsf->state));
break;
case SF_READ:
/*
* XXX: need to handle exotic behavior:
* - reading past end of device
*/
cnt = bytes - pos;
debug(" tx: read(%u)\n", cnt);
assert(tx);
ret = os_read(sbsf->fd, tx + pos, cnt);
if (ret < 0) {
puts("sandbox_sf: os_read() failed\n");
return -EIO;
}
pos += ret;
break;
case SF_READ_STATUS:
debug(" read status: %#x\n", sbsf->status);
cnt = bytes - pos;
memset(tx + pos, sbsf->status, cnt);
pos += cnt;
break;
case SF_READ_STATUS1:
debug(" read status: %#x\n", sbsf->status);
cnt = bytes - pos;
memset(tx + pos, sbsf->status >> 8, cnt);
pos += cnt;
break;
case SF_WRITE_STATUS:
debug(" write status: %#x (ignored)\n", rx[pos]);
pos = bytes;
break;
case SF_WRITE:
/*
* XXX: need to handle exotic behavior:
* - unaligned addresses
* - more than a page (256) worth of data
* - reading past end of device
*/
if (!(sbsf->status & STAT_WEL)) {
puts("sandbox_sf: write enable not set before write\n");
goto done;
}
cnt = bytes - pos;
debug(" rx: write(%u)\n", cnt);
if (tx)
sandbox_spi_tristate(&tx[pos], cnt);
ret = os_write(sbsf->fd, rx + pos, cnt);
if (ret < 0) {
puts("sandbox_spi: os_write() failed\n");
return -EIO;
}
pos += ret;
sbsf->status &= ~STAT_WEL;
break;
case SF_ERASE:
case_sf_erase: {
if (!(sbsf->status & STAT_WEL)) {
puts("sandbox_sf: write enable not set before erase\n");
goto done;
}
/* verify address is aligned */
if (sbsf->off & (sbsf->erase_size - 1)) {
debug(" sector erase: cmd:%#x needs align:%#x, but we got %#x\n",
sbsf->cmd, sbsf->erase_size,
sbsf->off);
sbsf->status &= ~STAT_WEL;
goto done;
}
debug(" sector erase addr: %u, size: %u\n", sbsf->off,
sbsf->erase_size);
cnt = bytes - pos;
if (tx)
sandbox_spi_tristate(&tx[pos], cnt);
pos += cnt;
/*
* TODO(vapier@gentoo.org): latch WIP in status, and
* delay before clearing it ?
*/
ret = sandbox_erase_part(sbsf, sbsf->erase_size);
sbsf->status &= ~STAT_WEL;
if (ret) {
debug("sandbox_sf: Erase failed\n");
goto done;
}
goto done;
}
default:
debug(" ??? no idea what to do ???\n");
goto done;
}
}
done:
if (flags & SPI_XFER_END)
sandbox_sf_cs_deactivate(dev);
return pos == bytes ? 0 : -EIO;
}
int sandbox_sf_ofdata_to_platdata(struct udevice *dev)
{
struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev);
pdata->filename = dev_read_string(dev, "sandbox,filename");
pdata->device_name = dev_read_string(dev, "compatible");
if (!pdata->filename || !pdata->device_name) {
debug("%s: Missing properties, filename=%s, device_name=%s\n",
__func__, pdata->filename, pdata->device_name);
return -EINVAL;
}
return 0;
}
static const struct dm_spi_emul_ops sandbox_sf_emul_ops = {
.xfer = sandbox_sf_xfer,
};
#ifdef CONFIG_SPI_FLASH
static int sandbox_cmdline_cb_spi_sf(struct sandbox_state *state,
const char *arg)
{
unsigned long bus, cs;
const char *spec = sandbox_spi_parse_spec(arg, &bus, &cs);
if (!spec)
return 1;
/*
* It is safe to not make a copy of 'spec' because it comes from the
* command line.
*
* TODO(sjg@chromium.org): It would be nice if we could parse the
* spec here, but the problem is that no U-Boot init has been done
* yet. Perhaps we can figure something out.
*/
state->spi[bus][cs].spec = spec;
debug("%s: Setting up spec '%s' for bus %ld, cs %ld\n", __func__,
spec, bus, cs);
return 0;
}
SANDBOX_CMDLINE_OPT(spi_sf, 1, "connect a SPI flash: <bus>:<cs>:<id>:<file>");
int sandbox_sf_bind_emul(struct sandbox_state *state, int busnum, int cs,
struct udevice *bus, int of_offset, const char *spec)
{
struct udevice *emul;
char name[20], *str;
struct driver *drv;
int ret;
/* now the emulator */
strncpy(name, spec, sizeof(name) - 6);
name[sizeof(name) - 6] = '\0';
strcat(name, "-emul");
drv = lists_driver_lookup_name("sandbox_sf_emul");
if (!drv) {
puts("Cannot find sandbox_sf_emul driver\n");
return -ENOENT;
}
str = strdup(name);
if (!str)
return -ENOMEM;
ret = device_bind(bus, drv, str, NULL, of_offset, &emul);
if (ret) {
free(str);
printf("Cannot create emul device for spec '%s' (err=%d)\n",
spec, ret);
return ret;
}
state->spi[busnum][cs].emul = emul;
return 0;
}
void sandbox_sf_unbind_emul(struct sandbox_state *state, int busnum, int cs)
{
struct udevice *dev;
dev = state->spi[busnum][cs].emul;
device_remove(dev, DM_REMOVE_NORMAL);
device_unbind(dev);
state->spi[busnum][cs].emul = NULL;
}
static int sandbox_sf_bind_bus_cs(struct sandbox_state *state, int busnum,
int cs, const char *spec)
{
struct udevice *bus, *slave;
int ret;
ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, true, &bus);
if (ret) {
printf("Invalid bus %d for spec '%s' (err=%d)\n", busnum,
spec, ret);
return ret;
}
ret = spi_find_chip_select(bus, cs, &slave);
if (!ret) {
printf("Chip select %d already exists for spec '%s'\n", cs,
spec);
return -EEXIST;
}
ret = device_bind_driver(bus, "spi_flash_std", spec, &slave);
if (ret)
return ret;
return sandbox_sf_bind_emul(state, busnum, cs, bus, -1, spec);
}
int sandbox_spi_get_emul(struct sandbox_state *state,
struct udevice *bus, struct udevice *slave,
struct udevice **emulp)
{
struct sandbox_spi_info *info;
int busnum = bus->seq;
int cs = spi_chip_select(slave);
int ret;
info = &state->spi[busnum][cs];
if (!info->emul) {
/* Use the same device tree node as the SPI flash device */
debug("%s: busnum=%u, cs=%u: binding SPI flash emulation: ",
__func__, busnum, cs);
ret = sandbox_sf_bind_emul(state, busnum, cs, bus,
dev_of_offset(slave), slave->name);
if (ret) {
debug("failed (err=%d)\n", ret);
return ret;
}
debug("OK\n");
}
*emulp = info->emul;
return 0;
}
int dm_scan_other(bool pre_reloc_only)
{
struct sandbox_state *state = state_get_current();
int busnum, cs;
if (pre_reloc_only)
return 0;
for (busnum = 0; busnum < CONFIG_SANDBOX_SPI_MAX_BUS; busnum++) {
for (cs = 0; cs < CONFIG_SANDBOX_SPI_MAX_CS; cs++) {
const char *spec = state->spi[busnum][cs].spec;
int ret;
if (spec) {
ret = sandbox_sf_bind_bus_cs(state, busnum,
cs, spec);
if (ret) {
debug("%s: Bind failed for bus %d, cs %d\n",
__func__, busnum, cs);
return ret;
}
debug("%s: Setting up spec '%s' for bus %d, cs %d\n",
__func__, spec, busnum, cs);
}
}
}
return 0;
}
#endif
static const struct udevice_id sandbox_sf_ids[] = {
{ .compatible = "sandbox,spi-flash" },
{ }
};
U_BOOT_DRIVER(sandbox_sf_emul) = {
.name = "sandbox_sf_emul",
.id = UCLASS_SPI_EMUL,
.of_match = sandbox_sf_ids,
.ofdata_to_platdata = sandbox_sf_ofdata_to_platdata,
.probe = sandbox_sf_probe,
.remove = sandbox_sf_remove,
.priv_auto_alloc_size = sizeof(struct sandbox_spi_flash),
.platdata_auto_alloc_size = sizeof(struct sandbox_spi_flash_plat_data),
.ops = &sandbox_sf_emul_ops,
};