[U-Boot-Users] Flash boot issues with MPC8272ADS and PQ2FADS

[Yuli Barcohen]

>>>>> Keath Milligan writes:

    Keath> We are using several PQ2FADS-VR and MPC8272ADS boards for a
    Keath> Linux project and are experiencing a high occurrence of
    Keath> boards that get into a state where they will not boot or
    Keath> behave erratically during boot.

    Keath> The symptoms are usually that board continually resets in
    Keath> u-boot. See below for output examples. In other cases, the
    Keath> system will get to the point of attempting to load a kernel,
    Keath> but will claim the checksum is bad, or will start booting the
    Keath> kernel and crash shortly thereafter.

    Keath> When folks bring me systems in this state, my "fix" has been
    Keath> to replace the 8MB flash SIMM. This usually gets them going
    Keath> again, but I honestly don't think the SIMM is the real
    Keath> problem. I have one PQ2FADS board that I have put four
    Keath> different SIMMs in and can not get it to boot. In most other
    Keath> cases, I can take the "bad" SIMM, put it in another board,
    Keath> reprogram it and it will work again (for a while).

    Keath> In all of these cases, we are using known good u-boots (built
    Keath> from unmodified 1.1.2 source for either the PQ2FADS or
    Keath> MPC8272ADS) and known good, tested kernels. Typically, users
    Keath> will have been working for weeks without a problem until they
    Keath> run into this.

MPC8272ADS is very unstable. We had to change three boards until we got
one which can work for some time without random reboots. Try to get the
board replaced by Freescale. PQ2FADS is much better though not perfect
as you noted:) We've got PQ2FADS-ZU (not VR) which can work for weeks
without reboots. First of all, I'd suggest checking the clocks. The
MPC8280 erratum regarding MF>=3.5 is in many cases the source of the
instability. Try to use MF<=3.

-- 
========================================================================
 Yuli Barcohen       | Phone +972-9-765-1788 |  Software Project Leader
 yuli at arabellasw.com | Fax   +972-9-765-7494 | Arabella Software, Israel
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