This driver allows to use SPI flash as backing store for boot counter values with DM enabled.
Signed-off-by: Sebastian Reichel sebastian.reichel@collabora.com --- drivers/bootcount/Kconfig | 10 +++ drivers/bootcount/Makefile | 1 + drivers/bootcount/spi-flash.c | 125 ++++++++++++++++++++++++++++++++++ 3 files changed, 136 insertions(+) create mode 100644 drivers/bootcount/spi-flash.c
diff --git a/drivers/bootcount/Kconfig b/drivers/bootcount/Kconfig index c8e6fa7f8925..b5ccea0d9c20 100644 --- a/drivers/bootcount/Kconfig +++ b/drivers/bootcount/Kconfig @@ -108,6 +108,16 @@ config DM_BOOTCOUNT_I2C_EEPROM pointing to the underlying i2c eeprom device) and an optional 'offset' property are supported.
+config DM_BOOTCOUNT_SPI_FLASH + bool "Support SPI flash devices as a backing store for bootcount" + depends on DM_SPI_FLASH + help + Enabled reading/writing the bootcount in a DM SPI flash device. + The wrapper device is to be specified with the compatible string + 'u-boot,bootcount-spi-flash' and the 'spi-flash'-property (a phandle + pointing to the underlying SPI flash device) and an optional 'offset' + property are supported. + config BOOTCOUNT_MEM bool "Support memory based bootcounter" help diff --git a/drivers/bootcount/Makefile b/drivers/bootcount/Makefile index 059d40d16b0c..51d860b00e18 100644 --- a/drivers/bootcount/Makefile +++ b/drivers/bootcount/Makefile @@ -12,3 +12,4 @@ obj-$(CONFIG_BOOTCOUNT_EXT) += bootcount_ext.o obj-$(CONFIG_DM_BOOTCOUNT) += bootcount-uclass.o obj-$(CONFIG_DM_BOOTCOUNT_RTC) += rtc.o obj-$(CONFIG_DM_BOOTCOUNT_I2C_EEPROM) += i2c-eeprom.o +obj-$(CONFIG_DM_BOOTCOUNT_SPI_FLASH) += spi-flash.o diff --git a/drivers/bootcount/spi-flash.c b/drivers/bootcount/spi-flash.c new file mode 100644 index 000000000000..7cd388e6616c --- /dev/null +++ b/drivers/bootcount/spi-flash.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2019 Collabora + * (C) Copyright 2019 GE + */ + +#include <common.h> +#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_alloc_size = sizeof(struct bootcount_spi_flash_priv), + .probe = bootcount_spi_flash_probe, + .of_match = bootcount_spi_flash_ids, + .ops = &bootcount_spi_flash_ops, +};