[coreboot-gerrit] Patch merged into coreboot/master: c09cf0b libpayload: arm: Pass the coreboot table location to the payload.

[gerrit at coreboot.org]

the following patch was just integrated into master:
commit c09cf0b7e17cc48576d09d3c48df8625ea5c990b
Author: Gabe Black <gabeblack at google.com>
Date:   Sat Feb 8 06:30:49 2014 -0800

    libpayload: arm: Pass the coreboot table location to the payload.
    
    To find the coreboot tables, the payload has historically searched for their
    signature in a predefined region of memory. This is a little clumsy on x86,
    but it works because you can assume certain regions are RAM. Also, there are
    areas which are set aside for the firmware by convention. On x86 there's a
    forwarding entry which goes in one of those fairly small conventional areas
    and which points to the CBMEM area at the end of memory.
    
    On ARM there aren't areas like that, so we've left out the forwarding entry and
    gone directly to CBMEM. RAM may not start at the beginning of the address space
    or go to its end, and that means there isn't really anywhere fixed you can put
    the coreboot tables. That's meant that libpayload has to be configured on a
    per board basis to know where to look for CBMEM.
    
    Now that we have boards that don't have fixed amounts of memory, the location
    of the end of RAM isn't fixed even on a per board level which means even that
    workaround will no longer cut it.
    
    This change makes coreboot pass the location of the coreboot tables to
    libpayload using r0, the first argument register. That means we'll be able to
    find them no matter where CBMEM is, and we can get rid of the per board search
    ranges.
    
    We can extend this mechanism to x86 as well, but there may be more
    complications and it's less necessary there. It would be a good thing to do
    eventually though.
    
    BUG=None
    TEST=Built and booted on nyan. Changed the size of memory and saw that the
    payload could still find the coreboot tables where before it couldn't. Built
    for pit, snow, and big.
    BRANCH=None
    
    Original-Change-Id: I7218afd999da1662b0db8172fd8125670ceac471
    Original-Signed-off-by: Gabe Black <gabeblack at google.com>
    Original-Reviewed-on: https://chromium-review.googlesource.com/185572
    Original-Reviewed-by: Julius Werner <jwerner at chromium.org>
    Original-Commit-Queue: Gabe Black <gabeblack at chromium.org>
    Original-Tested-by: Gabe Black <gabeblack at chromium.org>
    (cherry picked from commit ca88f39c21158b59abe3001f986207a292359cf5)
    Signed-off-by: Marc Jones <marc.jones at se-eng.com>
    
    Change-Id: Iab14e9502b6ce7a55f0a72e190fa582f89f11a1e
    Reviewed-on: http://review.coreboot.org/7655
    Tested-by: build bot (Jenkins)
    Reviewed-by: Paul Menzel <paulepanter at users.sourceforge.net>
    Reviewed-by: Patrick Georgi <pgeorgi at google.com>


See http://review.coreboot.org/7655 for details.

-gerrit