drm/i915/dsi: Add check for periodic command mode

If the GOP has programmed periodic command mode,
we need to disable that which would need a
deconfigure and configure sequence.

v2: Fix sparse error, pass only intel_dsi (Jani)
v3: Use intel_de_read

Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200312053841.2794-5-vandita.kulkarni@intel.com

diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
index 17aa3fd780a8796149da0788d1c643c30d059ca8..949f4867402baf388c5cc905e493fe26d559fe15 100644 (file)
--- a/drivers/gpu/drm/i915/display/icl_dsi.c
+++ b/drivers/gpu/drm/i915/display/icl_dsi.c
@@ -1423,6 +1423,22 @@ static void gen11_dsi_get_timings(struct intel_encoder *encoder,
        adjusted_mode->crtc_vblank_end = adjusted_mode->crtc_vtotal;
 }
 
+static bool gen11_dsi_is_periodic_cmd_mode(struct intel_dsi *intel_dsi)
+{
+       struct drm_device *dev = intel_dsi->base.base.dev;
+       struct drm_i915_private *dev_priv = to_i915(dev);
+       enum transcoder dsi_trans;
+       u32 val;
+
+       if (intel_dsi->ports == BIT(PORT_B))
+               dsi_trans = TRANSCODER_DSI_1;
+       else
+               dsi_trans = TRANSCODER_DSI_0;
+
+       val = intel_de_read(dev_priv, DSI_TRANS_FUNC_CONF(dsi_trans));
+       return (val & DSI_PERIODIC_FRAME_UPDATE_ENABLE);
+}
+
 static void gen11_dsi_get_config(struct intel_encoder *encoder,
                                 struct intel_crtc_state *pipe_config)
 {
@@ -1443,6 +1459,10 @@ static void gen11_dsi_get_config(struct intel_encoder *encoder,
        gen11_dsi_get_timings(encoder, pipe_config);
        pipe_config->output_types |= BIT(INTEL_OUTPUT_DSI);
        pipe_config->pipe_bpp = bdw_get_pipemisc_bpp(crtc);
+
+       if (gen11_dsi_is_periodic_cmd_mode(intel_dsi))
+               pipe_config->hw.adjusted_mode.private_flags |=
+                                       I915_MODE_FLAG_DSI_PERIODIC_CMD_MODE;
 }
 
 static int gen11_dsi_dsc_compute_config(struct intel_encoder *encoder,
@@ -1526,6 +1546,10 @@ static int gen11_dsi_compute_config(struct intel_encoder *encoder,
 
        pipe_config->port_clock = afe_clk(encoder, pipe_config) / 5;
 
+       /* We would not operate in periodic command mode */
+       pipe_config->hw.adjusted_mode.private_flags &=
+                                       ~I915_MODE_FLAG_DSI_PERIODIC_CMD_MODE;
+
        return 0;
 }