[U-Boot] config: enable CONFIG_API in distro config

[Stephen Warren]

On 04/18/2014 09:35 AM, Tom Rini wrote:
> On Thu, Apr 10, 2014 at 03:55:48PM -0500, Rob Herring wrote:
> 
>> From: Rob Herring <robh at kernel.org>
>>
>> CONFIG_API is needed for u-boot apps such as grub2, so enable it for
>> distro config.
>>
>> Cc: Dennis Gilmore <dennis at ausil.us>
>> Signed-off-by: Rob Herring <robh at kernel.org>
> 
> This breaks a number of boards that have opted in to the distro config.
> The full list is:
> whistler trimslice beaver tec paz00 ventana cardhu harmony dalmore
> plutux medcom-wide rpi_b venice2 colibri_t20_iris tec-ng seaboard
> 
> How do you guys want to handle this?  I can apply now and they can be
> fixed up later, or I can wait for fixup patches to come out and apply
> them all at once.  Thanks!

I've sent patches that solve all the build problems on Tegra with
CONFIG_API enabled.

That said, I still conceptually object to config_distro_defaults.h
enabling API support in order to support grub; I believe the distros
need to get together and nail down a *single* boot mechanism to
standardize upon, rather than having Fedora support BootloaderSpec,
Ubuntu/Linaro(?) support Grub, something else support LILO, something
else support UEFI, etc. Without this, we'll force every U-Boot binary to
be bloated with all kinds of redundant code. Having a single standard
mechanism was always the point of config_distro_defaults.h in my mind.

BTW, does Grub work well for you? I did try it many months ago, and found:

a) It was excruciatingly slow, to the point of not being useful.

b) The binary had hard-coded memory layout, and hence couldn't be
generic across multiple boards, since SoCs put their RAM in different
places, boards have differing amounts of RAM, etc. This kinda defeats
the whole purpose, since distros would need to install board-specific
Grub binaries. Perhaps this could be solved similarly to the kernel's
CONFIG_ARM_PATCH_PHYS_VIRT?

If we really need Grub support, wouldn't it be better to have U-Boot
parse and execute grub.cfg, just like it does extlinux.cfg?