[U-Boot] [PATCH 3/3] mx6: synchronize SPL to u-boot offset

[Max Krummenacher]

2016-10-17 14:45 GMT+02:00 Marek Vasut <marex at denx.de>:
> On 10/17/2016 02:28 PM, Max Krummenacher wrote:
>> Hi Marek
>>
>>>>>>  #if defined(CONFIG_SPL_MMC_SUPPORT)
>>>>>>  #define CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR    138 /*
>>>>>> offset 69KB */
>>>>>> +#define CONFIG_SPL_PAD_TO                  0x11000 /* offset
>>>>>> 68KB */
>>>>>
>>>>> Does this mess up boards which can boot from both SD and other boot
>>>>> media (NAND, SPI NOR, PNOR...) ?
>>>>
>>>> Good point.
>>>> CONFIG_SPL_PAD_TO is used to create the combined SPL/U-Boot binary.
>>>> While I have not found any use of this by any config which includes
>>>> imx6_spl.h it might hinder future boards.
>>>> So it's probably best to define CONFIG_SPL_PAD_TO in the individual
>>>> board configs and skip this patch.
>>>
>>> So how did you come up with this patch ? What was the thought process?
>>>
>> I'm preparing patches for submission of new boards, Colibri iMX6, Apalis iMX6.
>> They rely on this patchset
>> https://www.mail-archive.com/u-boot@lists.denx.de/msg227944.html, so
>> the board patches are not yet ready for submission.
>
> OT: Can you make those boards load u-boot.img from extfs partition instead ?

I probably could but did not try.

Also it would change the way we use U-Boot across our module family
and I'm worried that we more often need to recover over USB due to a
corrupted filesystem.
On top of that I made some measurements on loading the kernel from an
ext2 instead of an fat fs and have seen differences bigger than 100ms.
So parsing into a filesystem twice would probably add even more
overhead.

Max

>
>> I forward ported from a downstream 2015.04 U-Boot where 'make
>> u-boot-with-spl.imx' used an offset of 68KB between SPL and U-Boot
>> binary matching the SPL code which later loads U-Boot.
>> With the current master it used an offset of 64KB resulting in an SPL
>> not loading U-Boot.
>> Probably the 4KB stem from now counting SPL_PAD_TO from the start of
>> the IVT/DCD region and earlier counting from the start of SPL.
>
> I see, thanks for clarifying.
>
>> Max
>>
>
>
> --
> Best regards,
> Marek Vasut