[U-Boot] [PATCH] ARM: mx6ul: Apply ERR011115 errata workaround

[Stefano Babic]

Hi Marcin,

On 19/07/2018 13:37, Marcin Niestroj wrote:
> ERR011115 in IMX6UL errata says to use OCRAM memory above
> 0x908000 (instead of 0x907000) for silicon revision 1.2 shipped
> prior date code 1740.
> 
> As we cannot check affected targets in runtime, apply that
> workaround by default for all IMX6UL platforms. Leave possibility
> to disable that workaround for non-affected targets, so more OCRAM
> area can be used by SPL (e.g. for featureful SPL images).
> 


I had a project with this issue - anyway, I disagree to apply the
work-around for all MX6UL.

Rather, we have no possibilities to detect and solve this at runtime.
SPL is already loaded. But NXP has already fixed this in later
production. Companies already know if there production is affected or
not, and they can enable MX6UL_ERR011115 for their products.

We are already fighting with the OCRAM size, specially if other features
(HAB and secure boot, further filesystems) are enabled. Reducing size is
ok for some products (they cannot do in other way if they have some of
these broken devices), it is not ok for other ones.

I will propose to not set it as default for MX6UL.

> Signed-off-by: Marcin Niestroj <m.niestroj at grinn-global.com>
> ---
>  arch/arm/mach-imx/mx6/Kconfig |  9 +++++++++
>  include/configs/imx6_spl.h    | 11 +++++++++--
>  2 files changed, 18 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/mach-imx/mx6/Kconfig b/arch/arm/mach-imx/mx6/Kconfig
> index 521fad74b5..61708a0526 100644
> --- a/arch/arm/mach-imx/mx6/Kconfig
> +++ b/arch/arm/mach-imx/mx6/Kconfig
> @@ -58,6 +58,15 @@ config MX6UL
>  	select SYSCOUNTER_TIMER
>  	bool
>  
> +config MX6UL_ERR011115
> +	bool "Workaround for ERR011115 in IMX6UL Errata"
> +	depends on MX6UL
> +	default MX6UL
> +	help
> +	  Say N here if you are sure that your platform is not affected
> +	  with ERR011115. Doing so might be useful in case of featureful
> +	  (big) SPL images.

Boards Maintainer should decide themselves instead of setting this as
default.

> +
>  config MX6UL_LITESOM
>  	bool
>  	select MX6UL
> diff --git a/include/configs/imx6_spl.h b/include/configs/imx6_spl.h
> index 720ff045a7..42d12c7503 100644
> --- a/include/configs/imx6_spl.h
> +++ b/include/configs/imx6_spl.h
> @@ -19,16 +19,23 @@
>   *    which consists of a 4K header in front of us that contains the IVT, DCD
>   *    and some padding thus 'our' max size is really 0x00908000 - 0x00918000
>   *    or 64KB
> + *  - Use 0x00909000 as start of OCRAM Free Area as a workaround for
> + *    ERR011115 in IMX6UL Errata
>   */
> +#ifdef CONFIG_MX6UL_ERR011115
> +#define CONFIG_SPL_TEXT_BASE		0x00909000
> +#else
>  #define CONFIG_SPL_TEXT_BASE		0x00908000
> -#define CONFIG_SPL_MAX_SIZE		0x10000
> +#endif
> +
> +#define CONFIG_SPL_MAX_SIZE		(0x00918000 - CONFIG_SPL_TEXT_BASE)

Sebastian has already reported that this is wrong. Anyway, even if this
was correct, it would be another issue and should be fixed in a separate
patch. The issue in the commit messsage is fixed just moving
CONFIG_MX6UL_ERR011115.

>  #define CONFIG_SPL_STACK		0x0091FFB8
>  /*
>   * Pad SPL to 68KB (4KB header + 64KB max size). This allows to write the
>   * SPL/U-Boot combination generated with u-boot-with-spl.imx directly to a
>   * boot media (given that boot media specific offset is configured properly).
>   */
> -#define CONFIG_SPL_PAD_TO		0x11000
> +#define CONFIG_SPL_PAD_TO		(CONFIG_SPL_MAX_SIZE + 0x1000)
>  
>  /* MMC support */
>  #if defined(CONFIG_SPL_MMC_SUPPORT)
> 

Best regards,
Stefano Babic

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