[coreboot-gerrit] Patch merged into coreboot/master: bb932c5 nyan*: I2C: Implement bus clear when 'ARB_LOST' error occurs

[gerrit at coreboot.org]

the following patch was just integrated into master:
commit bb932c56f0ba7890697fe2666cc63d2a215d95f1
Author: Tom Warren <twarren at nvidia.com>
Date:   Wed Apr 30 14:51:38 2014 -0700

    nyan*: I2C: Implement bus clear when 'ARB_LOST' error occurs
    
    This is a fix for the 'Lost arb' we're seeing on Nyan* during
    reboot stress testing. It occurs when we are slamming the
    default PMIC registers with pmic_write_reg().
    
    Currently, I've only captured this a few times, and the bus
    clear seemed to work, as the PMIC writes continued (where
    they'd hang the system before bus clear) for a couple of regs,
    then it hangs hard, no messages, no 2nd lost arb, etc. So
    I've added code to the PMIC write function that will reset the
    SoC if any I2C error occurs. That seems to recover OK, i.e. on
    the next reboot the PMIC writes all go thru, boot is OK, kernel
    loads, etc.
    
    BUG=chrome-os-partner:28323
    BRANCH=nyan
    TEST=Tested on nyan. Built for nyan and nyan_big.
    
    Original-Change-Id: I1ac5e3023ae22c015105b7f0fb7849663b4aa982
    Original-Signed-off-by: Tom Warren <twarren at nvidia.com>
    Original-Reviewed-on: https://chromium-review.googlesource.com/197732
    Original-Reviewed-by: Julius Werner <jwerner at chromium.org>
    Original-Reviewed-by: Jimmy Zhang <jimmzhang at nvidia.com>
    (cherry picked from commit f445127e2d9e223a5ef9117008a7ac7631a7980c)
    Signed-off-by: Marc Jones <marc.jones at se-eng.com>
    
    Change-Id: I584d55b99d65f1e278961db6bdde1845cb01f3bc
    Reviewed-on: http://review.coreboot.org/7897
    Tested-by: build bot (Jenkins)
    Reviewed-by: David Hendricks <dhendrix at chromium.org>


See http://review.coreboot.org/7897 for details.

-gerrit