Commit aceb365c authored by Shobhit Kumar's avatar Shobhit Kumar Committed by Daniel Vetter
Browse files

drm/i915/vlv: Update the DSI ULPS entry/exit sequence 

We should keep DEVICE_READY bit set in the ULPS enter sequence. In
exit sequence also we should set DEVICE_READY, but thats causing
blankout for me. Also exit sequence is simplified as per hw team
recommendation.

This should fix -
[drm:intel_dsi_clear_device_ready] *ERROR* DSI LP not going Low

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=80818


Signed-off-by: default avatarShobhit Kumar <shobhit.kumar@intel.com>
Tested-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
parent a799a978

drivers/gpu/drm/i915/intel_dsi.c

+15 −14
Original line number Diff line number Diff line
@@ -117,17 +117,18 @@ static void intel_dsi_device_ready(struct intel_encoder *encoder) 
	/* bandgap reset is needed after everytime we do power gate */

	band_gap_reset(dev_priv);



	I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_ENTER);

	usleep_range(2500, 3000);



	val = I915_READ(MIPI_PORT_CTRL(pipe));

	I915_WRITE(MIPI_PORT_CTRL(pipe), val | LP_OUTPUT_HOLD);

	usleep_range(1000, 1500);

	I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY | ULPS_STATE_EXIT);

	usleep_range(2000, 2500);

	I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY);

	usleep_range(2000, 2500);

	I915_WRITE(MIPI_DEVICE_READY(pipe), 0x00);

	usleep_range(2000, 2500);



	I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_EXIT);

	usleep_range(2500, 3000);



	I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY);

	usleep_range(2000, 2500);

	usleep_range(2500, 3000);

}



static void intel_dsi_enable(struct intel_encoder *encoder)
@@ -271,23 +272,23 @@ static void intel_dsi_clear_device_ready(struct intel_encoder *encoder) 


	DRM_DEBUG_KMS("\n");



	I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_ENTER);

	I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY | ULPS_STATE_ENTER);

	usleep_range(2000, 2500);



	I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_EXIT);

	I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY | ULPS_STATE_EXIT);

	usleep_range(2000, 2500);



	I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_ENTER);

	I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY | ULPS_STATE_ENTER);

	usleep_range(2000, 2500);



	val = I915_READ(MIPI_PORT_CTRL(pipe));

	I915_WRITE(MIPI_PORT_CTRL(pipe), val & ~LP_OUTPUT_HOLD);

	usleep_range(1000, 1500);



	if (wait_for(((I915_READ(MIPI_PORT_CTRL(pipe)) & AFE_LATCHOUT)

					== 0x00000), 30))

		DRM_ERROR("DSI LP not going Low\n");



	val = I915_READ(MIPI_PORT_CTRL(pipe));

	I915_WRITE(MIPI_PORT_CTRL(pipe), val & ~LP_OUTPUT_HOLD);

	usleep_range(1000, 1500);



	I915_WRITE(MIPI_DEVICE_READY(pipe), 0x00);

	usleep_range(2000, 2500);

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