[PATCH V4] ARM: tegra: disable LP2 cpuidle state if PCIe is enabled

[thierry.reding@gmail.com (Thierry Reding)]

On Mon, Aug 12, 2013 at 10:00:04AM -0600, Stephen Warren wrote:
> From: Stephen Warren <swarren@nvidia.com>
> 
> Tegra20 HW appears to have a bug such that PCIe device interrupts,
> whether they are legacy IRQs or MSI, are lost when LP2 is enabled. To
> work around this, simply disable LP2 if any PCIe devices with interrupts
> are present. Detect this via the IRQ domain map operation. This is
> slightly over-conservative; if a device with an interrupt is present but
> the driver does not actually use them, LP2 will still be disabled.
> However, this is a reasonable trade-off which enables a simpler
> workaround.
> 
> Signed-off-by: Stephen Warren <swarren@nvidia.com>
> Tested-by: Thierry Reding <treding@nvidia.com>
> Acked-by: Thierry Reding <treding@nvidia.com>
> ---
> v4: Add missing tegra-cpuidle.h, re-write commit description. Add acks.
> 
> v3: Only disable LP2 if a PCIe device that requests an interrupt is
> actually present. This prevents the loss of power-saving when the WAR
> isn't required.

Great, looks good to me and I see that you've applied it to your tree
already. This has been in the works for (literally!) years and it's
quite a relief to see it finally merged.

Thanks a lot!

Thierry
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