[meta-xilinx] [U-BOOT PATCH] zynq_common: Add uEnv.txt boot environment load support

[Michal Simek]

On 09/04/2013 07:21 AM, Nathan Rossi wrote:
>> -----Original Message-----
>> From: Michal Simek [mailto:michal.simek at xilinx.com]
>> Sent: Wednesday, September 04, 2013 2:42 PM
>> To: Philip Balister
>> Cc: Michal Simek; Nathan Rossi; git; meta-xilinx at yoctoproject.org;
>> Jagannadha Sutradharudu Teki
>> Subject: Re: [U-BOOT PATCH] zynq_common: Add uEnv.txt boot environment
>> load support
>>
>> On 09/03/2013 09:43 PM, Philip Balister wrote:
>>> On 09/02/2013 03:40 AM, Michal Simek wrote:
>>>> Hi,
>>>>
>>>> On 08/30/2013 08:13 AM, Nathan Rossi wrote:
>>>>> Add support for using a uEnv.txt file for loading and or modifying the
>>>>> existing boot environment during a Zynq "sdboot". If the environment
>>>>> fails to load during the "sdboot" continue booting from SD normally.
>>>>>
>>>>> This uEnv.txt and bootenv/uenv default environment variables are based
>>>>> on the implementation used in omap3_beagle.h.
>>>>>
>>>>> Signed-off-by: Nathan Rossi <nathan.rossi at xilinx.com>
>>>>> ---
>>>>> Hi All,
>>>>>
>>>>> This is a feature that has been requested by some users of the meta-
>> xilinx
>>>>> layer. It is the additional of an optional 'uEnv.txt' boot environment
>> file
>>>>> which allows the modification of the SD boot. It is very useful for
>> development
>>>>> purposes and also in production environments. (There are also some
>> specific
>>>>> development boards that would greatly benefit from this, specifcally
>> the
>>>>> Parallella board which cannot directly boot from SD card due to its
>> use of SD_1
>>>>> instead of SD_0, this would make boot environment modifications
>> significantly
>>>>> easier)
>>>>>
>>>>> Philip has done an initial implementation of this feature see:
>>>>> https://github.com/balister/meta-
>> xilinx/commit/8b66cb1edb65c34c332888e907aec4333422af6b#L1R1
>>>>>
>>>>> However I would like to see this accepted into the u-boot-xlnx for the
>> next
>>>>> release. So I have reworked Philip's initial implementation (based on
>> some
>>>>> comments from Michal).
>>>>>
>>>>> When this is accepted into the master-next branch of u-boot-xlnx I
>> will backport
>>>>> it for use in the Yocto meta-xilinx layer.
>>>>>
>>>>> Regards,
>>>>> Nathan
>>>>> ---
>>>>>  include/configs/zynq_common.h |   28 ++++++++++++++++++++++------
>>>>>  1 file changed, 22 insertions(+), 6 deletions(-)
>>>>
>>>> Applied to the master-next.
>>>
>>> I built u-boot-2013.07 + this patch and it failed to ru the commands
>>> from the uEnv.txt file until I increased the value of SYS_MAXARGS.
>>>
>>
>> Nathan: Have you tested that patch?
>>
>> Thanks,
>> Michal
>>
>>
> 
> Hi Michal,
> 
> Yes I tested the patch, however I did not test long environment variables which appears to be the issue that Philip has. This is the uEnv.txt he is using. https://github.com/balister/meta-xilinx/blob/boot-bin-1/recipes-bsp/u-boot/u-boot-xlnx/zedboard-zynq7/uEnv.txt-sd-boot
> 
> Which is not an issue with the uEnv commands, but merely an issue with environment variables in u-boot in general. Other platforms that use the uEnv.txt implementation tend to increase the CONFIG_SYS_MAXARGS definition to a value above the default but not all do.
> 
> omap3_beagle (which increases it to 32)
> http://git.denx.de/?p=u-boot.git;a=blob;f=include/configs/omap3_beagle.h;h=c1245e7b841e1c633b217ba0daf933abe363df0f;hb=HEAD#l324
> omap3_mvblx.h (which sets it to 16)
> http://git.denx.de/?p=u-boot.git;a=blob;f=include/configs/omap3_mvblx.h;h=0c88419f245eff14a7b8cd2b3244fec6d05fc088;hb=HEAD#l220
> 
> Is 'CONFIG_SYS_MAXARGS' something that u-boot-xlnx would want to have increased, or does it affect the expectations of U-Boot to significantly?

ok - Let's increase this value to 32.
Philip is 32 enough for your purpose?

Thanks,
Michal