Re: [PATCH 2/2] drm/i915: By default, enable RC6 on IVB and SNB when reasonable

On Fri, Dec 09, 2011 at 03:53:49PM -0800, Keith Packard wrote:

RC6 should always work on IVB, and should work on SNB whenever IO remapping is disabled. RC6 never works on Ironlake. Make the default value for the parameter follow these guidelines. Setting the value to either 0 or 1 will force the specified behavior.

I still don't like this. We're in a situation where we clearly have to disable one feature or the other on SNB - but we're disabling the one that's going to be useful to a large number of people, and leaving the niche feature enabled. If we're going to merge this then let's turn off iommu on SNB by default.