[PATCH 0/2] Errata workaround updates

On Wed, Feb 01, 2012 at 04:26:18PM +0000, Nicolas Pitre wrote:

On Wed, 1 Feb 2012, Will Deacon wrote:

quoted

Hello,

After Russell pointed out that we weren't applying an erratum workaround
in all cases that it was required:

http://lists.infradead.org/pipermail/linux-arm-kernel/2012-January/082730.html

I went back through the documents for PL310 and Cortex-A9 to check that
what we have in Linux matches the latest workarounds.

Ideally, you should not limit the workaround only to those revisions 
known to be broken but to any revision.  Only when a particular revision 
is known to be fixed then should it be disabled.

For the general case I'd be inclined to agree, but when it involves poking
undocumented diagnostic registers I get scared and would rather only do it
when we know it's safe (since it could easily cause more problems on other
versions of the CPU).

Will