Re: [PATCH] ARM: beaglebone: add delay in lowlevel.c

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

On 08.01.25 16:27, Konstantin Kletschke wrote:
> More like this?
> 
> On Wed, Jan 08, 2025 at 04:19:49PM +0100, Ahmad Fatoum wrote:
>>
>> It would be nice to have the comment more verbose. e.g. that this issue
>> was observed on new Seeed-produced BBBs is an intersting info IMO.
> 
>  arch/arm/boards/beaglebone/lowlevel.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/arch/arm/boards/beaglebone/lowlevel.c b/arch/arm/boards/beaglebone/lowlevel.c
> index 5dc49dfaaf..7dc338d03a 100644
> --- a/arch/arm/boards/beaglebone/lowlevel.c
> +++ b/arch/arm/boards/beaglebone/lowlevel.c
> @@ -97,6 +97,12 @@ extern char __dtb_z_am335x_boneblack_start[];
>  extern char __dtb_z_am335x_bone_common_start[];
>  extern char __dtb_z_am335x_bone_start[];
> 
> +static void __udelay(int us)
> +{
> +        volatile int i;
> +       for (i = 0; i < us; i++);
> +}
> +
>  /**
>   * @brief The basic entry point for board initialization.
>   *
> @@ -135,6 +141,12 @@ static noinline int beaglebone_sram_init(void)
>         am33xx_enable_uart0_pin_mux();
>         omap_debug_ll_init();
>         putc_ll('>');
> +       /*
> +        * Some (~5%) Beaglebone Black received from SEEED in batches
> +        * after autumn 2024 require a delay to be able to warm start
> +        * after reset

Sounds good. Please add

Link: https://lore.barebox.org/barebox/Z0gywL2hLcIDoLQ8@hephaistos/

to your commit message before the S-o-b and then it's good to go, I think.

Thanks,
Ahmad

> +        */
> +       __udelay(3000);
> 
>         barebox_arm_entry(0x80000000, sdram_size, fdt);
>  }
> 
> 
> 
> 
> 


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