Re: [PATCH 2/8] stm32mp: stm32prog: add CONFIG_CMD_STM32PROG_OTP

[Patrice CHOTARD <patrice.chotard@foss.st.com>]

On 3/28/22 19:25, Patrick Delaunay wrote:
> Add a configuration flag CONFIG_CMD_STM32PROG_OTP to enable the support of
> OTP update in stm32prog command.
> 
> This new configuration allows to deactivate this feature for security reason
> and it is a preliminary step for support of OPT update with the OP-TEE
> provisioning TA.
> 
> Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
> ---
> 
>  arch/arm/mach-stm32mp/cmd_stm32prog/Kconfig   |  7 ++
>  .../mach-stm32mp/cmd_stm32prog/stm32prog.c    | 66 +++++++++++--------
>  2 files changed, 46 insertions(+), 27 deletions(-)
> 
> diff --git a/arch/arm/mach-stm32mp/cmd_stm32prog/Kconfig b/arch/arm/mach-stm32mp/cmd_stm32prog/Kconfig
> index dd166a1f91..81d2b87035 100644
> --- a/arch/arm/mach-stm32mp/cmd_stm32prog/Kconfig
> +++ b/arch/arm/mach-stm32mp/cmd_stm32prog/Kconfig
> @@ -31,3 +31,10 @@ config CMD_STM32PROG_SERIAL
>  		activate the command "stm32prog serial" for STM32MP soc family
>  		with the tools STM32CubeProgrammer using U-Boot serial device
>  		and UART protocol.
> +
> +config CMD_STM32PROG_OTP
> +	bool "support stm32prog for OTP update"
> +	depends on CMD_STM32PROG
> +	default y if ARM_SMCCC
> +	help
> +		Support the OTP update with the command "stm32prog" for STM32MP
> diff --git a/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c b/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c
> index d513a60efb..3e9354b51d 100644
> --- a/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c
> +++ b/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c
> @@ -1154,7 +1154,9 @@ static int dfu_init_entities(struct stm32prog_data *data)
>  	struct dfu_entity *dfu;
>  	int alt_nb;
>  
> -	alt_nb = 2; /* number of virtual = CMD, OTP*/
> +	alt_nb = 1; /* number of virtual = CMD*/
> +	if (IS_ENABLED(CONFIG_CMD_STM32PROG_OTP))
> +		alt_nb++; /* OTP*/
>  	if (CONFIG_IS_ENABLED(DM_PMIC))
>  		alt_nb++; /* PMIC NVMEM*/
>  
> @@ -1205,7 +1207,7 @@ static int dfu_init_entities(struct stm32prog_data *data)
>  	if (!ret)
>  		ret = stm32prog_alt_add_virt(dfu, "virtual", PHASE_CMD, CMD_SIZE);
>  
> -	if (!ret)
> +	if (!ret && IS_ENABLED(CONFIG_CMD_STM32PROG_OTP)) {
>  		ret = stm32prog_alt_add_virt(dfu, "OTP", PHASE_OTP, OTP_SIZE);
>  
>  	if (!ret && CONFIG_IS_ENABLED(DM_PMIC))
> @@ -1226,6 +1228,11 @@ int stm32prog_otp_write(struct stm32prog_data *data, u32 offset, u8 *buffer,
>  {
>  	log_debug("%s: %x %lx\n", __func__, offset, *size);
>  
> +	if (!IS_ENABLED(CONFIG_CMD_STM32PROG_OTP)) {
> +		stm32prog_err("OTP update not supported");
> +
> +		return -EOPNOTSUPP;
> +	}
>  	if (!data->otp_part) {
>  		data->otp_part = memalign(CONFIG_SYS_CACHELINE_SIZE, OTP_SIZE);
>  		if (!data->otp_part)
> @@ -1248,10 +1255,10 @@ int stm32prog_otp_read(struct stm32prog_data *data, u32 offset, u8 *buffer,
>  {
>  	int result = 0;
>  
> -	if (!IS_ENABLED(CONFIG_ARM_SMCCC)) {
> +	if (!IS_ENABLED(CONFIG_CMD_STM32PROG_OTP)) {
>  		stm32prog_err("OTP update not supported");
>  
> -		return -1;
> +		return -EOPNOTSUPP;
>  	}
>  
>  	log_debug("%s: %x %lx\n", __func__, offset, *size);
> @@ -1270,8 +1277,10 @@ int stm32prog_otp_read(struct stm32prog_data *data, u32 offset, u8 *buffer,
>  		memset(data->otp_part, 0, OTP_SIZE);
>  
>  		/* call the service */
> -		result = stm32_smc_exec(STM32_SMC_BSEC, STM32_SMC_READ_ALL,
> -					(u32)data->otp_part, 0);
> +		result = -EOPNOTSUPP;
> +		if (IS_ENABLED(CONFIG_ARM_SMCCC))
> +			result = stm32_smc_exec(STM32_SMC_BSEC, STM32_SMC_READ_ALL,
> +						(u32)data->otp_part, 0);
>  		if (result)
>  			goto end_otp_read;
>  	}
> @@ -1296,10 +1305,10 @@ int stm32prog_otp_start(struct stm32prog_data *data)
>  	int result = 0;
>  	struct arm_smccc_res res;
>  
> -	if (!IS_ENABLED(CONFIG_ARM_SMCCC)) {
> +	if (!IS_ENABLED(CONFIG_CMD_STM32PROG_OTP)) {
>  		stm32prog_err("OTP update not supported");
>  
> -		return -1;
> +		return -EOPNOTSUPP;
>  	}
>  
>  	if (!data->otp_part) {
> @@ -1307,28 +1316,31 @@ int stm32prog_otp_start(struct stm32prog_data *data)
>  		return -1;
>  	}
>  
> -	arm_smccc_smc(STM32_SMC_BSEC, STM32_SMC_WRITE_ALL,
> -		      (u32)data->otp_part, 0, 0, 0, 0, 0, &res);
> +	result = -EOPNOTSUPP;
> +	if (IS_ENABLED(CONFIG_ARM_SMCCC)) {
> +		arm_smccc_smc(STM32_SMC_BSEC, STM32_SMC_WRITE_ALL,
> +			      (u32)data->otp_part, 0, 0, 0, 0, 0, &res);
>  
> -	if (!res.a0) {
> -		switch (res.a1) {
> -		case 0:
> -			result = 0;
> -			break;
> -		case 1:
> -			stm32prog_err("Provisioning");
> -			result = 0;
> -			break;
> -		default:
> -			log_err("%s: OTP incorrect value (err = %ld)\n",
> -				__func__, res.a1);
> +		if (!res.a0) {
> +			switch (res.a1) {
> +			case 0:
> +				result = 0;
> +				break;
> +			case 1:
> +				stm32prog_err("Provisioning");
> +				result = 0;
> +				break;
> +			default:
> +				log_err("%s: OTP incorrect value (err = %ld)\n",
> +					__func__, res.a1);
> +				result = -EINVAL;
> +				break;
> +			}
> +		} else {
> +			log_err("%s: Failed to exec svc=%x op=%x in secure mode (err = %ld)\n",
> +				__func__, STM32_SMC_BSEC, STM32_SMC_WRITE_ALL, res.a0);
>  			result = -EINVAL;
> -			break;
>  		}
> -	} else {
> -		log_err("%s: Failed to exec svc=%x op=%x in secure mode (err = %ld)\n",
> -			__func__, STM32_SMC_BSEC, STM32_SMC_WRITE_ALL, res.a0);
> -		result = -EINVAL;
>  	}
>  
>  	free(data->otp_part);
Applied to u-boot-stm32

Thanks
Patrice