Commits
Lyude committed f165d2834ce
drm/i915/ilk: Don't disable SSC source if it's in use Thanks to Ville Syrjälä for pointing me towards the cause of this issue. Unfortunately one of the sideaffects of having the refclk for a DPLL set to SSC is that as long as it's set to SSC, the GPU will prevent us from powering down any of the pipes or transcoders using it. A couple of BIOSes enable SSC in both PCH_DREF_CONTROL and in the DPLL configurations. This causes issues on the first modeset, since we don't expect SSC to be left on and as a result, can't successfully power down the pipes or the transcoders using it. Here's an example from this Dell OptiPlex 990: [drm:intel_modeset_init] SSC enabled by BIOS, overriding VBT which says disabled [drm:intel_modeset_init] 2 display pipes available. [drm:intel_update_cdclk] Current CD clock rate: 400000 kHz [drm:intel_update_max_cdclk] Max CD clock rate: 400000 kHz [drm:intel_update_max_cdclk] Max dotclock rate: 360000 kHz vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem [drm:intel_crt_reset] crt adpa set to 0xf40000 [drm:intel_dp_init_connector] Adding DP connector on port C [drm:intel_dp_aux_init] registering DPDDC-C bus for card0-DP-1 [drm:ironlake_init_pch_refclk] has_panel 0 has_lvds 0 has_ck505 0 [drm:ironlake_init_pch_refclk] Disabling SSC entirely … later we try committing the first modeset … [drm:intel_dump_pipe_config] [CRTC:26][modeset] config ffff88041b02e800 for pipe A [drm:intel_dump_pipe_config] cpu_transcoder: A … [drm:intel_dump_pipe_config] dpll_hw_state: dpll: 0xc4016001, dpll_md: 0x0, fp0: 0x20e08, fp1: 0x30d07 [drm:intel_dump_pipe_config] planes on this crtc [drm:intel_dump_pipe_config] STANDARD PLANE:23 plane: 0.0 idx: 0 enabled [drm:intel_dump_pipe_config] FB:42, fb = 800x600 format = 0x34325258 [drm:intel_dump_pipe_config] scaler:0 src (0, 0) 800x600 dst (0, 0) 800x600 [drm:intel_dump_pipe_config] CURSOR PLANE:25 plane: 0.1 idx: 1 disabled, scaler_id = 0 [drm:intel_dump_pipe_config] STANDARD PLANE:27 plane: 0.1 idx: 2 disabled, scaler_id = 0 [drm:intel_get_shared_dpll] CRTC:26 allocated PCH DPLL A [drm:intel_get_shared_dpll] using PCH DPLL A for pipe A [drm:ilk_audio_codec_disable] Disable audio codec on port C, pipe A [drm:intel_disable_pipe] disabling pipe A ------------[ cut here ]------------ WARNING: CPU: 1 PID: 130 at drivers/gpu/drm/i915/intel_display.c:1146 intel_disable_pipe+0x297/0x2d0 [i915] pipe_off wait timed out … ---[ end trace 94fc8aa03ae139e8 ]--- [drm:intel_dp_link_down] [drm:ironlake_crtc_disable [i915]] *ERROR* failed to disable transcoder A Later modesets succeed since they reset the DPLL's configuration anyway, but this is enough to get stuck with a big fat warning in dmesg. A better solution would be to add refcounts for the SSC source, but for now leaving the source clock on should suffice. Changes since v3: - Move temp variable into loop - Move checks for using_ssc_source to after we've figured out has_ck505 - Add using_ssc_source to debug output Changes since v2: - Fix debug output for when we disable the CPU source Changes since v1: - Leave the SSC source clock on instead of just shutting it off on all of the DPLL configurations. Cc: stable@vger.kernel.org Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Lyude <cpaul@redhat.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1464199863-9397-1-git-send-email-cpaul@redhat.com