[coreboot-gerrit] Patch merged into coreboot/master: 9482498 arm64: Add support for save/restore registers for CPU startup.

[gerrit at coreboot.org]

the following patch was just integrated into master:
commit 9482498003d500db6aced4c94bf4ab3485cab18e
Author: Furquan Shaikh <furquan at google.com>
Date:   Fri Nov 21 15:42:40 2014 -0800

    arm64: Add support for save/restore registers for CPU startup.
    
    startup.c provides function to enable CPU in any stage to save register data
    that can be used by secondary CPU (for normal boot) or any CPU (for resume
    boot). stage_entry.S defines space for saving arm64_startup_data. This can be
    filled by:
    1) Primary CPU before bringing up secondary CPUs so that the secondary can use
    register values to initialize MMU-related and other required registers to
    appropriate values.
    2) CPU suspend path to ensure that on resume the values which were saved are
    restored appropriately.
    
    stage_entry.S provides a common path for both normal and resume boot to
    initialize saved registers. For resume path, it is important to set the
    secondary entry point for startup since x26 needs to be 1 for enabling MMU and
    cache.
    
    This also ensures that we do not fall into false memory cache errors which
    caused CPU to fail during normal / resume boot. Thus, we can get rid of the
    stack cache invalidate for secondary CPUs.
    
    BUG=chrome-os-partner:33962
    BRANCH=None
    TEST=Compiles and boots both CPU0 and CPU1 on ryu without mmu_enable and stack
    cache invalidate for CPU1.
    
    Change-Id: Ia4ca0e7d35c0738dbbaa926cce4268143c6f9de3
    Signed-off-by: Patrick Georgi <pgeorgi at chromium.org>
    Original-Commit-Id: 9f5e78469313ddd144ad7cf5abc3e07cb712183a
    Original-Signed-off-by: Furquan Shaikh <furquan at google.com>
    Original-Change-Id: I527a95779cf3fed37392b6605b096f54f8286d64
    Original-Reviewed-on: https://chromium-review.googlesource.com/231561
    Original-Reviewed-by: Aaron Durbin <adurbin at chromium.org>
    Original-Tested-by: Furquan Shaikh <furquan at chromium.org>
    Original-Commit-Queue: Furquan Shaikh <furquan at chromium.org>
    Reviewed-on: http://review.coreboot.org/9540
    Tested-by: build bot (Jenkins)
    Reviewed-by: Stefan Reinauer <stefan.reinauer at coreboot.org>


See http://review.coreboot.org/9540 for details.

-gerrit