[PATCH v2] ARM: Define wfi() macro for v6 processors

[Dave Martin]

On Tue, Feb 8, 2011 at 4:20 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Tue, Feb 08, 2011 at 02:45:51PM +0000, Dave Martin wrote:
>> If support for a v6K processor is included, we have no way to know
>> from preprocessor definitions whether a plain v6 processor is also to
>> be supported.
>
> Yes we do.  See the v6 patches I've recently posted to various mailing
> lists.
>
> This patch series was created in the hope that it could be tested by a
> sufficient number of people so that it could go into -rc1 as at the
> moment, omap2plus_defconfig builds data-corrupting kernels.
>
> Unfortunately, the response was not as good as I was hoping - it's
> possible to count the number of testers on one hand.  So it's now
> scheduled for the next merge window.  What this means is that v2.6.37
> and v2.6.38 omap2plus_defconfig kernels _will_ _be_ _unsafe_ when run
> on SMP hardware, and will remain that way.  If a fix is not suitable for
> -rc, it most certainly isn't suitable for -stable.
> What the patch set does demonstrate that we can know at preprocessor
> time that plain v6 processors should be supported along side v6k and
> v7.

Fair enough--- I hadn't fully understood the implications there, since
I'm not really working with the v6 case for now.  Adding a
CPU_V6/CPU_V6K distinction does seem to solve that specific problem.
Unfortunately, I'm not in a position to test that easily...

I think I will alter my OMAP Thumb-2 support patches to avoid the
generic wfi() macro for now -- simply to decouple the dependency
pending discussion about system*.h.  This can be fixed later, if
appropriate.

Cheers
---Dave