[U-Boot] [PATCH] PowerPC MPC85xx: don't hang on read exception

[Liu Dave-R63238]

> I agree that this is the better approach, and I would be delighted if
> somebody would write and submit that code for both u-boot and Linux.
> It's a few hundred lines and takes careful testing, as we found with
> our proprietary OS.

In fact. u-boot has some support for these error events, check the
cpu/mpc85xx/interrupts, 8548cds, 8544ds board file and drivers/pci
/fsl-pci...c. beside they has not good framework.

Linux kernel has the EDAC driver for 85xx platform in main tree, include
most of error case.

> In the meantime, both u-boot and Linux are susceptible to processor
> stalls.  This one-line patch replaces those stalls with exceptions.
> The machine check exception handler won't diagnose the problem (e.g.,
> it won't display "localbus parity error,") but at least we know that
> something happened and we have a register dump with which to begin
> analyzing the problem.

What is error you usually happened? L2 cache, ECM mapping, PCI[x,ex]
error
or local bus error?