Display Refresh Rate Switching (DRRS) is a power conservation feature which enables swtching between low and high refresh rates, dynamically, based on the usage scenario to save power. This feature is applicable for internal panels. Indication that the panel supports DRRS is given by the panel EDID, which would list multiple refresh rates for one resolution along with VBT fields like drrs_min_vrefresh. DRRS is of 2 types - static and seamless. Static needs full modeset. Which can be used in docking and undocking scenarios. Seamless DRRS involves changing RR without any visual effect to the user and can be used during normal system usage. This is done by programming certain registers. Support for static/seamless DRRS may be indicated in the VBT based on inputs from the panel spec. We have implemented two DRRS use case scenrios : 1. Idleness DRRS, 2. Media playback DRRS (Content's FPS based) Idleness DRRS:- The implementation is based on frontbuffer tracking implementation. When there is a disturbance on the screen triggered by user activity or a periodic system activity, DRRS is disabled (RR is changed to high RR). When there is no movement on screen, after a timeout, a switch to low RR is made. For integration with frontbuffer tracking code, intel_drrs_invalidate() and intel_drrs_flush() are called. Media playback DRRS (Content's FPS based): Based on the content's Frames Per Second, minimum required vrefresh is called in userspace. If the panel supports the minimum required vrefresh and if the DRRS is supported on the platform, userspace will make a modeset request with same mode and FB but with different vrefresh. Panel's vrefresh range will be exposed through connector's modelist and connector property is created to expose the DRRS capability to the userspace. In DRRS state machine Media plyabck DRRS holds the highest priority. Idleness DRRS is disabled as soon as Media playback DRRS is requested. Idleness DRRS is reenabled when the userspace indicates the exit of Media playback DRRS by requesting for highest vrefresh supported. NOTE: 1. DRM documentation will be made once the RFC is closed along with IGT. 2. Currently in RFC, platform support is developed only for VLV. it will be extended to other platform once the design is approved. 3. Basic design of DSI DRRS and Content based DRRS is functionally tested on Android(VLV & CHT). Ramalingam C (18): drm/i915: Removing the eDP specific DRRS implementation drm/i915: Generic DRRS state Machine drm/i915: Addition of the drrs_min_vrefresh in VBT drm/i915: Implementation of Generic DSI DRRS drm/i915: Adjusting the pclk for dual link and burst mode drm/i915: VLV dsi drrs support drm/i915: Generic eDP DRRS implementation drm/i915: VLV eDP DRRS methods drm/i915: Cloned mode check drm/i915: Initializing DRRS for all connectors drm/i915: Updating the crtc modes in DRRS transitions drm/i915: Redesigning dp_set_m_n to receive divider values drm/i915: MEDIA_RR support in general DRRS state machine drm/i915: MEDIA_RR support in eDP DRRS module drm/i915: MEDIA_RR support in DSI DRRS module drm/i915: Filtering media playback DRRS requests drm/i915: Addition of downclock mode to connector modelist drm/i915: Connector property for DRRS capability drivers/gpu/drm/i915/Makefile | 3 + drivers/gpu/drm/i915/i915_debugfs.c | 110 ----- drivers/gpu/drm/i915/i915_drv.h | 91 +++- drivers/gpu/drm/i915/i915_reg.h | 4 + drivers/gpu/drm/i915/intel_bios.c | 3 + drivers/gpu/drm/i915/intel_bios.h | 9 +- drivers/gpu/drm/i915/intel_ddi.c | 2 - drivers/gpu/drm/i915/intel_display.c | 57 ++- drivers/gpu/drm/i915/intel_dp.c | 397 +--------------- drivers/gpu/drm/i915/intel_drrs.c | 728 ++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_drrs.h | 38 ++ drivers/gpu/drm/i915/intel_drv.h | 45 +- drivers/gpu/drm/i915/intel_dsi.c | 29 +- drivers/gpu/drm/i915/intel_dsi.h | 3 + drivers/gpu/drm/i915/intel_dsi_drrs.c | 415 +++++++++++++++++ drivers/gpu/drm/i915/intel_dsi_drrs.h | 66 +++ drivers/gpu/drm/i915/intel_dsi_pll.c | 303 +++++++++++-- drivers/gpu/drm/i915/intel_edp_drrs.c | 196 ++++++++ drivers/gpu/drm/i915/intel_edp_drrs.h | 29 ++ drivers/gpu/drm/i915/intel_frontbuffer.c | 4 +- drivers/gpu/drm/i915/intel_modes.c | 28 ++ 21 files changed, 1959 insertions(+), 601 deletions(-) create mode 100644 drivers/gpu/drm/i915/intel_drrs.c create mode 100644 drivers/gpu/drm/i915/intel_drrs.h create mode 100644 drivers/gpu/drm/i915/intel_dsi_drrs.c create mode 100644 drivers/gpu/drm/i915/intel_dsi_drrs.h create mode 100644 drivers/gpu/drm/i915/intel_edp_drrs.c create mode 100644 drivers/gpu/drm/i915/intel_edp_drrs.h -- 1.7.9.5 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
