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Description of problem:
Kernel problems related to the newest revision of the Apple G5 Dual Processor Systems.

Reference:

http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.12-rc5

Benjamin Herrenschmidt <benh@kernel.crashing.org>:
    [PATCH] ppc64: Fix booting on latest G5 models

    The latest speedbumped Apple G5 models have a "bug" in the Open Firmware
    device tree that lacks the proper interrupt routing information for the
    northbridge i2c controller.  Apple's driver silently falls back into a
    sub-optimal "polled" mode (heh, maybe they didn't even notice the bug
    because of that :), our driver didn't properly check and crashes :(

    This patch fixes our driver to not crash, and adds code to the
    prom_init() OF trampoline code that detects the "bug" and adds the
    missing information back for this chipset revision.  This fixes booting
    and thermal control on these models.

    Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Benjamin Herrenschmidt <benh@kernel.crashing.org>:
    [PATCH] ppc64: Fix g5 hw timebase sync

    The hardware sync of the timebase on SMP G5s uses a black magic
    incantation to the i2c clock chip that was inspired from what Darwin
    does.

    However, this was an earlier version of Darwin that was ...  buggy !
    heh.  This causes the latest models to break though when starting SMP,
    so it's worth fixing.

    Here's a new version of the incantation based on careful transcription
    of the said incantations as found in the latest version of apple's
    temple.

    Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Signed-off-by: Linus Torvalds <torvalds@osdl.org>



Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1.Boot any Linux PPC64 Kernel < 2.6.12
2.Kernel Panic After I2C Probe
 

Additional info: