This driver allows to use SPI flash as backing store for
boot counter values with DM enabled.
Signed-off-by: Sebastian Reichel <sebastian.reic...@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,
+};
--
2.28.0
