Commits
Tom O'Rourke committed 93ee29203f5
drm/i915: Use efficient frequency for HSW/BDW Added gen6_init_rps_frequencies() to initialize the rps frequency values. This function replaces parse_rp_state_cap(). In addition to reading RPn, RP0, and RP1 from RP_STATE_CAP register, the new function reads efficient frequency (aka RPe) from pcode for Haswell and Broadwell and sets the turbo softlimits. The turbo minimum frequency softlimit is set to RPe for Haswell and Broadwell and to RPn otherwise. For RPe, the efficiency is based on the frequency/power ratio (MHz/W); this is considering GT power and not package power. The efficent frequency is the highest frequency for which the frequency/power ratio is within some threshold of the highest frequency/power ratio. A fixed decrease in frequency results in smaller decrease in power at frequencies less than RPe than at frequencies above RPe. v2: Following suggestions from Chris Wilson and Daniel Vetter to extend and rename parse_rp_state_cap and to open-code a poorly named function. Signed-off-by: Tom O'Rourke <Tom.O'Rourke@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> [danvet: Remove unused variables.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>