[U-Boot] [RFC] Proposal on changing raw boot mode

[Sam Protsenko]

Hi guys,

I'd like to make two changes on how raw MMC address and size of U-Boot
are represented. But I think it's better to discuss it first, so we
are on the same page about it.

Basically I want to review two config options here.

1. CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS

    Simple grep shows us that noone actually uses this constant
(despite it's being defined for multiple boards). So I'm thinking to
remove it altogether. What do you think about that?

2. CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR

    For TI boards it's defined in common file:
include/configs/ti_armv7_common.h . So if some board has another
U-Boot partition address (on MMC), it must redefine that option after
including ti_armv7_common.h.

    Historical background: actually I tried to change this address
before, because DRA7 EVM and AM57x EVM / X15 boards are broken in
mainline U-Boot right now. My attempt [1] turned out to be
ill-designed, as it broke other boards (IIRC, it was BeagleBone
Black): [2]. Which further led to reverting my patch: [3].

    It remains to be a problem, though. So I see 2 possible ways how to fix it:

    (a) Just re-define this address in corresponding board configs (headers).
    (b) Convert this option to Kconfig and define it correctly in each
board's defconfig.

It would be great to hear your thoughts about those two items, so we
can avoid resending/discarding of patches due to under-communication.

Thanks!

[1] http://lists.denx.de/pipermail/u-boot/2016-April/252060.html
[2] http://lists.denx.de/pipermail/u-boot/2016-May/253407.html
[3] http://lists.denx.de/pipermail/u-boot/2016-May/253408.html