blob: 155d0323ee78477d2f52ff9785b1ff90d05c523d [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2019 Collabora
* (C) Copyright 2019 GE
*/
#include <bootcount.h>
#include <dm.h>
#include <spi_flash.h>
static const u8 bootcount_magic = 0xbc;
struct bootcount_spi_flash_priv {
struct udevice *spi_flash;
u32 offset;
};
static int bootcount_spi_flash_update(struct udevice *dev, u32 offset, u32 len, const void *buf)
{
struct spi_flash *flash = dev_get_uclass_priv(dev);
u32 sector_size = flash->sector_size;
u32 sector_offset = offset % sector_size;
u32 sector = offset - sector_offset;
int err = 0;
/* code only supports updating a single sector */
if (sector_offset + len > sector_size)
return -ENOSYS;
u8 *buffer = malloc(sector_size);
if (!buffer)
return -ENOMEM;
err = spi_flash_read_dm(dev, sector, sector_size, buffer);
if (err < 0)
goto out;
memcpy(buffer + sector_offset, buf, len);
err = spi_flash_erase_dm(dev, sector, sector_size);
if (err < 0)
goto out;
err = spi_flash_write_dm(dev, sector, sector_size, buffer);
if (err < 0)
goto out;
out:
free(buffer);
return err;
}
static int bootcount_spi_flash_set(struct udevice *dev, const u32 a)
{
struct bootcount_spi_flash_priv *priv = dev_get_priv(dev);
const u16 val = bootcount_magic << 8 | (a & 0xff);
if (bootcount_spi_flash_update(priv->spi_flash, priv->offset, 2, &val) < 0) {
debug("%s: write failed\n", __func__);
return -EIO;
}
return 0;
}
static int bootcount_spi_flash_get(struct udevice *dev, u32 *a)
{
struct bootcount_spi_flash_priv *priv = dev_get_priv(dev);
u16 val;
if (spi_flash_read_dm(priv->spi_flash, priv->offset, 2, &val) < 0) {
debug("%s: read failed\n", __func__);
return -EIO;
}
if (val >> 8 == bootcount_magic) {
*a = val & 0xff;
return 0;
}
debug("%s: bootcount magic does not match on %04x\n", __func__, val);
return -EIO;
}
static int bootcount_spi_flash_probe(struct udevice *dev)
{
struct ofnode_phandle_args phandle_args;
struct bootcount_spi_flash_priv *priv = dev_get_priv(dev);
struct udevice *spi_flash;
if (dev_read_phandle_with_args(dev, "spi-flash", NULL, 0, 0, &phandle_args)) {
debug("%s: spi-flash backing device not specified\n", dev->name);
return -ENOENT;
}
if (uclass_get_device_by_ofnode(UCLASS_SPI_FLASH, phandle_args.node, &spi_flash)) {
debug("%s: could not get backing device\n", dev->name);
return -ENODEV;
}
priv->spi_flash = spi_flash;
priv->offset = dev_read_u32_default(dev, "offset", 0);
return 0;
}
static const struct bootcount_ops bootcount_spi_flash_ops = {
.get = bootcount_spi_flash_get,
.set = bootcount_spi_flash_set,
};
static const struct udevice_id bootcount_spi_flash_ids[] = {
{ .compatible = "u-boot,bootcount-spi-flash" },
{ }
};
U_BOOT_DRIVER(bootcount_spi_flash) = {
.name = "bootcount-spi-flash",
.id = UCLASS_BOOTCOUNT,
.priv_auto = sizeof(struct bootcount_spi_flash_priv),
.probe = bootcount_spi_flash_probe,
.of_match = bootcount_spi_flash_ids,
.ops = &bootcount_spi_flash_ops,
};