[U-Boot] [PATCH v2 3/7] stm32: stm32f7: add spl build support

[Vikas MANOCHA]

Hi,

> On Aug 18, 2017, at 6:31 PM, Robert Nelson <robertcnelson at gmail.com> wrote:
> 
>> On Fri, Aug 18, 2017 at 4:28 PM, Vikas MANOCHA <vikas.manocha at st.com> wrote:
>> Hi Bo,
>> 
>>> -----Original Message-----
>>> From: Bo Shen [mailto:voice.shen at gmail.com]
>>> Sent: Thursday, August 17, 2017 10:07 PM
>>> To: Robert Nelson <robertcnelson at gmail.com>; Vikas MANOCHA <vikas.manocha at st.com>
>>> Cc: U-Boot-Denx <u-boot at lists.denx.de>; Christophe PRIOUZEAU <christophe.priouzeau at st.com>; Alexandre TORGUE
>>> <alexandre.torgue at st.com>
>>> Subject: Re: [U-Boot] [PATCH v2 3/7] stm32: stm32f7: add spl build support
>>> 
>>> 
>>> Hi Vikas,
>>>   Try to remove this magic (press 'c' on the keyboard when at the boot time),
>> 
>> It helps to select between U-Boot or OS booting.
>> 
>>> I'd suggest to add a follow-up patch to move all the
>>> selected SPL related configuration from "arch/arm/mach-stm32/Kconfig" under STM32F7 to default configuration file (stm32f746-
>>> disco_defconfig). Then if the people want just boot up u-boot itself, what they need to do is just run "make menuconfig" and then de-
>>> select "Activate Falcon Mode"
>>> (SPL_OS_BOOT). Then everything will be fine.
>> 
>> Yes, Agree. How about using "imply" instead of "select" for SPL_OS_BOOT to make it configurable.
> 
> Well, we really need a /doc/README.stm32 that explains this
> "different" default..  It's definitely different then
> omap/imx/tegra/atmel in this tree. But the processor is also more
> handicapped, so not wasting time in normal u-boot just booting the
> kernel via spl/falcon more makes sense.

That's the current configuration with one additional key entry check which is insignificant in terms of any overhead.

Making SPL_OS_BOOT configurable is also adding option to compile spl to boot UBoot directly without any overhead.

Cheers,
Vikas 

> 
> Regards,
> 
> -- 
> Robert Nelson
> https://rcn-ee.com/