On Fri, 23 Mar 2012 11:57:19 -0300, Eugeni Dodonov <eugeni.dodonov at intel.com> wrote: > This is yet another chapter in the ongoing saga of bringing RC6 to Sandy > Bridge machines by default. > > Now that we have discovered that RC6 issues are triggered by RC6+ state, > let's try to disable it by default. Plain RC6 is the one responsible for > most energy savings, and so far it haven't given any problems - at least, > none we are aware of. > > So with this, when i915_enable_rc6=-1 (e.g., the default value), we'll > attempt to enable plain RC6 only on SNB. For Ivy Bridge, the behavior > stays the same as always - we enable both RC6 and deep RC6. > > Note that while this exact patch does not has explicit tested-by's, the > equivalent settings were fixed in 3.3 kernel by a smaller patch. And it > has also received considerable testing through Canonical RC6 task-force > testing at https://wiki.ubuntu.com/Kernel/PowerManagementRC6. Up to date, > it looks like all the known issues are gone. > > v2: improve description and reference a couple of open bugs related to > RC6 which seem to be fixed with this change. > > References: https://bugs.freedesktop.org/show_bug.cgi?id=41682 > References: https://bugs.freedesktop.org/show_bug.cgi?id=38567 > References: https://bugs.freedesktop.org/show_bug.cgi?id=44867 > Signed-off-by: Eugeni Dodonov <eugeni.dodonov at intel.com> Acked-by: Chris Wilson <chris at chris-wilson.co.uk> -Chris -- Chris Wilson, Intel Open Source Technology Centre
