On Tue, 07 Mar 2023 22:12:49 -0800, Belgaumkar, Vinay wrote: > Hi Vinay, > On 3/7/2023 9:33 PM, Ashutosh Dixit wrote: > > Using common freq functions with sysfs in PMU (but without taking > > forcewake) solves the following issues (a) missing support for MTL (b) > > For the requested_freq, we read it only if actual_freq is zero below > (meaning, GT is in C6). So then what is the point of reading it without a > force wake? It will also be zero, correct? Yes agreed. I had tested this and you do see values for requested freq which look correct even when actual freq is 0 even without taking forcewake. That is why I ended up writing Patch 2/3. However what I missed is what you pointed out that 0xa008 is a shadowed register which cannot be read without taking forcewake. It is probably returning the last value which was written to the shadowed write register. As a result I have dropped the "drm/i915/rps: Expose get_requested_frequency_fw for PMU" patch in v2 of this series. Thanks. -- Ashutosh
