Re: [PATCH v9 07/15] FWU: STM32MP1: Add support to read boot index from backup register

Etienne Carriere
2022-09-06T07:27:47Z

Hi Sughosh,

I have a last comment on this series, related to the below patch and
patch "test: dm: Add test cases for FWU Metadata uclass".

On Fri, 26 Aug 2022 at 11:58, Sughosh Ganu <sughosh.ganu@linaro.org> wrote:
>
> The FWU Multi Bank Update feature allows the platform to boot the
> firmware images from one of the partitions(banks). The first stage
> bootloader(fsbl) passes the value of the boot index, i.e. the bank
> from which the firmware images were booted from to U-Boot. On the
> STM32MP157C-DK2 board, this value is passed through one of the SoC's
> backup register. Add a function to read the boot index value from the
> backup register.
>
> Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
> Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
> Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
> ---
> Changes since V8: None
>
> arch/arm/mach-stm32mp/include/mach/stm32.h | 5 +++++
> board/st/stm32mp1/stm32mp1.c | 23 ++++++++++++++++++++++
> include/fwu.h | 12 +++++++++++
> 3 files changed, 40 insertions(+)
>
> diff --git a/arch/arm/mach-stm32mp/include/mach/stm32.h b/arch/arm/mach-stm32mp/include/mach/stm32.h
> index c70375a723..c85ae6a34e 100644
> --- a/arch/arm/mach-stm32mp/include/mach/stm32.h
> +++ b/arch/arm/mach-stm32mp/include/mach/stm32.h
> @@ -112,11 +112,16 @@ enum boot_device {
> #ifdef CONFIG_STM32MP15x
> #define TAMP_BACKUP_MAGIC_NUMBER TAMP_BACKUP_REGISTER(4)
> #define TAMP_BACKUP_BRANCH_ADDRESS TAMP_BACKUP_REGISTER(5)
> +#define TAMP_FWU_BOOT_INFO_REG TAMP_BACKUP_REGISTER(10)
> #define TAMP_COPRO_RSC_TBL_ADDRESS TAMP_BACKUP_REGISTER(17)
> #define TAMP_COPRO_STATE TAMP_BACKUP_REGISTER(18)
> #define TAMP_BOOT_CONTEXT TAMP_BACKUP_REGISTER(20)
> #define TAMP_BOOTCOUNT TAMP_BACKUP_REGISTER(21)
>
> +#define TAMP_FWU_BOOT_IDX_MASK GENMASK(3, 0)
> +
> +#define TAMP_FWU_BOOT_IDX_OFFSET 0
> +
> #define TAMP_COPRO_STATE_OFF 0
> #define TAMP_COPRO_STATE_INIT 1
> #define TAMP_COPRO_STATE_CRUN 2
> diff --git a/board/st/stm32mp1/stm32mp1.c b/board/st/stm32mp1/stm32mp1.c
> index bfec0a710d..dd95babb49 100644
> --- a/board/st/stm32mp1/stm32mp1.c
> +++ b/board/st/stm32mp1/stm32mp1.c
> @@ -966,3 +966,26 @@ static void board_copro_image_process(ulong fw_image, size_t fw_size)
> }
>
> U_BOOT_FIT_LOADABLE_HANDLER(IH_TYPE_COPRO, board_copro_image_process);
> +
> +#if defined(CONFIG_FWU_MULTI_BANK_UPDATE)
> +
> +#include <fwu.h>
> +
> +/**
> + * fwu_plat_get_bootidx() - Get the value of the boot index
> + * @boot_idx: Boot index value
> + *
> + * Get the value of the bank(partition) from which the platform
> + * has booted. This value is passed to U-Boot from the earlier
> + * stage bootloader which loads and boots all the relevant
> + * firmware images
> + *
> + */
> +void fwu_plat_get_bootidx(void *boot_idx)
> +{
> + u32 *bootidx = boot_idx;
> +
> + *bootidx = (readl(TAMP_FWU_BOOT_INFO_REG) >>
> + TAMP_FWU_BOOT_IDX_OFFSET) & TAMP_FWU_BOOT_IDX_MASK;
> +}
> +#endif /* CONFIG_FWU_MULTI_BANK_UPDATE */
> diff --git a/include/fwu.h b/include/fwu.h
> index 7ebd3a7115..b8c207deaf 100644
> --- a/include/fwu.h
> +++ b/include/fwu.h
> @@ -240,4 +240,16 @@ int fwu_plat_get_alt_num(struct udevice *dev, efi_guid_t *image_guid,
> *
> */
> int fwu_plat_get_update_index(uint *update_idx);
> +
> +/**
> + * fwu_plat_get_bootidx() - Get the value of the boot index
> + * @boot_idx: Boot index value
> + *
> + * Get the value of the bank(partition) from which the platform
> + * has booted. This value is passed to U-Boot from the earlier
> + * stage bootloader which loads and boots all the relevant
> + * firmware images
> + *
> + */
> +void fwu_plat_get_bootidx(void *boot_idx);

It's maybe not clean to pass a void * to something callee shall write to.
Could the reference be passed with an explicit type pointer as 'unsigned int *'?

Best regards,
Etienne

> #endif /* _FWU_H_ */
> --
> 2.34.1
>