Re: [DistroKit] [PATCH 11/11] v7a: barebox: enable HWRNG drivers and allow fallback to PRNG

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hi Roland,

On 5/26/25 12:11, Roland Hieber wrote:
> Without ALLOW_PRNG_FALLBACK, barebox prints an unsightly error message
> on boot:
> 
>     ERROR: no HWRNG available!

Is this because of the stack protector? Which platforms lack the RNG?

Cheers,
Ahmad

> 
> Since we don't have HWRNG drivers for all available platforms, enable
> those that we have (RPi and AM33xx). For the other platforms allow
> fallback to the PRNG, which will at least only print a warning on boot
> on platforms without HWRNG:
> 
>     WARNING: falling back to Pseudo RNG source!
> 
> … but in this case, this is expected.
> 
> Signed-off-by: Roland Hieber <rhi@pengutronix.de>
> ---
>  configs/platform-v7a/barebox.config | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/configs/platform-v7a/barebox.config b/configs/platform-v7a/barebox.config
> index 4780b6493a7a..86cb40acbf17 100644
> --- a/configs/platform-v7a/barebox.config
> +++ b/configs/platform-v7a/barebox.config
> @@ -1106,9 +1106,9 @@ CONFIG_HWRNG=y
>  # CONFIG_HW_RANDOM_TIMERIOMEM is not set
>  CONFIG_HWRNG_STM32=y
>  CONFIG_HW_RANDOM_OPTEE=y
> -# CONFIG_HW_RANDOM_BCM2835 is not set
> +CONFIG_HW_RANDOM_BCM2835=y
>  # CONFIG_HW_RANDOM_IPROC_RNG200 is not set
> -# CONFIG_HW_RANDOM_OMAP is not set
> +CONFIG_HW_RANDOM_OMAP=y
>  
>  #
>  # DMA support
> @@ -1380,7 +1380,7 @@ CONFIG_IMAGE_SPARSE=y
>  CONFIG_STMP_DEVICE=y
>  CONFIG_LIBFDT=y
>  # CONFIG_RATP is not set
> -# CONFIG_ALLOW_PRNG_FALLBACK is not set
> +CONFIG_ALLOW_PRNG_FALLBACK=y
>  # CONFIG_CRC_CCITT is not set
>  CONFIG_CRC8=y
>  

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