In order to save the bootcounter on raw flash device, this commit introduces a new bootcount driver, enabled using the CONFIG_BOOTCOUNT_FLASH option.
The bootcounter is stored at address CONFIG_SYS_BOOTCOUNT_FLASH_ADDR (absolute address, can also be computed from CONFIG_SYS_BOOTCOUNT_FLASH_OFFSET), and it uses a data structure providing several useful enhancements: - a `flags` field, used to check whether the bootcounter should be written to flash (similar to the `upgrade_available` environment variable) - a `crc` field to ensure integrity of the structure, which will be used later on when adding redundancy support - a `data` field, which can be used to store and pass user data between u-boot and the OS (e.g boot partition selection)
Signed-off-by: Arnaud Ferraris arnaud.ferraris@collabora.com ---
drivers/bootcount/Kconfig | 14 ++++++ drivers/bootcount/Makefile | 1 + drivers/bootcount/bootcount_flash.c | 78 +++++++++++++++++++++++++++++ include/bootcount.h | 12 +++++ scripts/config_whitelist.txt | 2 + 5 files changed, 107 insertions(+) create mode 100644 drivers/bootcount/bootcount_flash.c
diff --git a/drivers/bootcount/Kconfig b/drivers/bootcount/Kconfig index 0e506c9ea2..94de3f5ef8 100644 --- a/drivers/bootcount/Kconfig +++ b/drivers/bootcount/Kconfig @@ -66,6 +66,20 @@ config BOOTCOUNT_I2C CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for the bootcounter.
+config BOOTCOUNT_FLASH + bool "Boot counter on flash device" + help + Store the bootcounter on raw flash. The bootcounter will be stored + as a structure using one flash sector, and will only be written when + a specific flag is set in the structure. Additionnally, this driver + relies on one of the following to be defined: + + CONFIG_SYS_BOOTCOUNT_FLASH_ADDR = address used for storing the + bootcounter on flash. + or + CONFIG_SYS_BOOTCOUNT_FLASH_OFFSET = bootcounter offset on flash + (relative to SYS_FLASH_BASE). + config BOOTCOUNT_AT91 bool "Boot counter for Atmel AT91SAM9XE" depends on AT91SAM9XE diff --git a/drivers/bootcount/Makefile b/drivers/bootcount/Makefile index 73ccfb5a08..bddcd136f3 100644 --- a/drivers/bootcount/Makefile +++ b/drivers/bootcount/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_BOOTCOUNT_RAM) += bootcount_ram.o obj-$(CONFIG_BOOTCOUNT_ENV) += bootcount_env.o obj-$(CONFIG_BOOTCOUNT_I2C) += bootcount_i2c.o obj-$(CONFIG_BOOTCOUNT_EXT) += bootcount_ext.o +obj-$(CONFIG_BOOTCOUNT_FLASH) += bootcount_flash.o
obj-$(CONFIG_DM_BOOTCOUNT) += bootcount-uclass.o obj-$(CONFIG_DM_BOOTCOUNT_RTC) += rtc.o diff --git a/drivers/bootcount/bootcount_flash.c b/drivers/bootcount/bootcount_flash.c new file mode 100644 index 0000000000..1222bb4ae0 --- /dev/null +++ b/drivers/bootcount/bootcount_flash.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2020 Collabora Ltd. All rights reserved. + */ + +#include <bootcount.h> +#include <common.h> +#include <asm/io.h> +#include <u-boot/crc.h> +#include <flash.h> + +#ifndef CONFIG_SYS_BOOTCOUNT_FLASH_ADDR +# ifdef CONFIG_SYS_BOOTCOUNT_FLASH_OFFSET +# define CONFIG_SYS_BOOTCOUNT_FLASH_ADDR \ + (CONFIG_SYS_FLASH_BASE + CONFIG_SYS_BOOTCOUNT_FLASH_OFFSET) +# else +# error "Either CONFIG_SYS_BOOTCOUNT_FLASH_ADDR or " \ + "CONFIG_SYS_BOOTCOUNT_FLASH_OFFSET should be defined!" +# endif +#endif + +#define BOOTCOUNT_CRC_SIZE (sizeof(*bootcount) - sizeof(bootcount->crc)) + +static struct bootcount *bootcount = (void *)CONFIG_SYS_BOOTCOUNT_ADDR; +static ulong bc_flash = CONFIG_SYS_BOOTCOUNT_FLASH_ADDR; +static ulong bc_flash_end = + CONFIG_SYS_BOOTCOUNT_FLASH_ADDR + CONFIG_SYS_FLASH_SECT_SIZE - 1; + +static void bootcount_write(void) +{ + if (flash_sect_protect(0, bc_flash, bc_flash_end)) + return; + + puts("Erasing Flash...\n"); + if (flash_sect_erase(bc_flash, bc_flash_end)) + return; + + puts("Writing bootcount to Flash...\n"); + if (flash_write((char *)bootcount, bc_flash, sizeof(*bootcount))) + return; + + flash_sect_protect(1, bc_flash, bc_flash_end); +} + +static void bootcount_init(void) +{ + memset(bootcount, 0, sizeof(*bootcount)); + bootcount->magic = CONFIG_SYS_BOOTCOUNT_MAGIC; + bootcount->crc = crc32(0, (uchar *)bootcount, BOOTCOUNT_CRC_SIZE); + bootcount_write(); +} + +void bootcount_store(ulong a) +{ + bootcount->count = a; + bootcount->crc = crc32(0, (uchar *)bootcount, BOOTCOUNT_CRC_SIZE); + if (bootcount->flags & BOOTCOUNT_FLAGS_UPDATE) + bootcount_write(); +} + +ulong bootcount_load(void) +{ + static int initialized; + u32 crc; + + if (!initialized) { + memcpy(bootcount, (void *)bc_flash, sizeof(*bootcount)); + initialized = 1; + } + + crc = crc32(0, (uchar *)bootcount, BOOTCOUNT_CRC_SIZE); + if (bootcount->magic != CONFIG_SYS_BOOTCOUNT_MAGIC || + bootcount->crc != crc) { + bootcount_init(); + } + + return bootcount->count; +} diff --git a/include/bootcount.h b/include/bootcount.h index cd30403984..5698bd3239 100644 --- a/include/bootcount.h +++ b/include/bootcount.h @@ -79,6 +79,18 @@ ulong bootcount_load(void); # endif #endif
+#ifdef CONFIG_BOOTCOUNT_FLASH +struct bootcount { + u32 magic; + u32 count; + u32 flags; + u32 data; + u32 crc; +}; + +#define BOOTCOUNT_FLAGS_UPDATE 0x1 +#endif + #ifdef CONFIG_SYS_BOOTCOUNT_LE static inline void raw_bootcount_store(volatile u32 *addr, u32 data) { diff --git a/scripts/config_whitelist.txt b/scripts/config_whitelist.txt index 6908431d03..672483f040 100644 --- a/scripts/config_whitelist.txt +++ b/scripts/config_whitelist.txt @@ -1829,6 +1829,8 @@ CONFIG_SYS_BOARD_NAME CONFIG_SYS_BOARD_OMAP3_HA CONFIG_SYS_BOOK3E_HV CONFIG_SYS_BOOTCOUNT_BE +CONFIG_SYS_BOOTCOUNT_FLASH_ADDR +CONFIG_SYS_BOOTCOUNT_FLASH_OFFSET CONFIG_SYS_BOOTCOUNT_LE CONFIG_SYS_BOOTFILE_PREFIX CONFIG_SYS_BOOTMAPSZ