[Intel-gfx] [PATCH 05/11] drm/i915: Add support for port enable/disable for dual link configuration

[Gaurav K Singh]

For Dual Link MIPI Panels, both Port A and Port C should be enabled
during the MIPI encoder enabling sequence. Similarly, during the
disabling sequence, both ports needs to be disabled.

Signed-off-by: Gaurav K Singh <gaurav.k.singh at intel.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h            |    1 +
 drivers/gpu/drm/i915/intel_dsi.c           |   55 ++++++++++++++++++++++------
 drivers/gpu/drm/i915/intel_dsi.h           |    1 +
 drivers/gpu/drm/i915/intel_dsi_panel_vbt.c |    1 +
 4 files changed, 47 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 021f72b..b2fc92b 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -6403,6 +6403,7 @@ enum punit_power_well {
 #define  DPI_ENABLE					(1 << 31) /* A + B */
 #define  MIPIA_MIPI4DPHY_DELAY_COUNT_SHIFT		27
 #define  MIPIA_MIPI4DPHY_DELAY_COUNT_MASK		(0xf << 27)
+#define  DUAL_LINK_MODE_SHIFT				26
 #define  DUAL_LINK_MODE_MASK				(1 << 26)
 #define  DUAL_LINK_MODE_FRONT_BACK			(0 << 26)
 #define  DUAL_LINK_MODE_PIXEL_ALTERNATIVE		(1 << 26)
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 69828c3..2c30b61 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -108,14 +108,33 @@ static void intel_dsi_port_enable(struct intel_encoder *encoder)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+	enum pipe pipe = intel_crtc->pipe;
 	int port = PIPE_MAPPED_TO_MIPI_PORT(intel_crtc->pipe);
-	u32 temp;
-
-	/* assert ip_tg_enable signal */
-	temp = I915_READ(MIPI_PORT_CTRL(port)) & ~LANE_CONFIGURATION_MASK;
-	temp = temp | intel_dsi->port_bits;
-	I915_WRITE(MIPI_PORT_CTRL(port), temp | DPI_ENABLE);
-	POSTING_READ(MIPI_PORT_CTRL(port));
+	u32 temp, port_control = 0;
+
+	if (intel_dsi->dual_link) {
+		port_control = (intel_dsi->dual_link - 1)
+					<< DUAL_LINK_MODE_SHIFT;
+		port_control |= pipe ? LANE_CONFIGURATION_DUAL_LINK_B :
+					LANE_CONFIGURATION_DUAL_LINK_A;
+		/*For Port A */
+		temp = I915_READ(MIPI_PORT_CTRL(0));
+		temp = temp | port_control;
+		I915_WRITE(MIPI_PORT_CTRL(0), temp | DPI_ENABLE);
+		POSTING_READ(MIPI_PORT_CTRL(0));
+
+		/* For Port C */
+		temp = I915_READ(MIPI_PORT_CTRL(1));
+		I915_WRITE(MIPI_PORT_CTRL(1), temp | DPI_ENABLE);
+		POSTING_READ(MIPI_PORT_CTRL(1));
+	} else {
+		/* assert ip_tg_enable signal */
+		temp = I915_READ(MIPI_PORT_CTRL(port)) &
+						~LANE_CONFIGURATION_MASK;
+		temp = temp | intel_dsi->port_bits;
+		I915_WRITE(MIPI_PORT_CTRL(port), temp | DPI_ENABLE);
+		POSTING_READ(MIPI_PORT_CTRL(port));
+	}
 }
 
 static void intel_dsi_port_disable(struct intel_encoder *encoder)
@@ -123,13 +142,26 @@ static void intel_dsi_port_disable(struct intel_encoder *encoder)
 	struct drm_device *dev = encoder->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
 	int port = PIPE_MAPPED_TO_MIPI_PORT(intel_crtc->pipe);
 	u32 temp;
 
-	/* de-assert ip_tg_enable signal */
-	temp = I915_READ(MIPI_PORT_CTRL(port));
-	I915_WRITE(MIPI_PORT_CTRL(port), temp & ~DPI_ENABLE);
-	POSTING_READ(MIPI_PORT_CTRL(port));
+	if (intel_dsi->dual_link) {
+		/*For Port A */
+		temp = I915_READ(MIPI_PORT_CTRL(0));
+		I915_WRITE(MIPI_PORT_CTRL(0), temp & ~DPI_ENABLE);
+		POSTING_READ(MIPI_PORT_CTRL(0));
+
+		/* For Port C */
+		temp = I915_READ(MIPI_PORT_CTRL(1));
+		I915_WRITE(MIPI_PORT_CTRL(1), temp & ~DPI_ENABLE);
+		POSTING_READ(MIPI_PORT_CTRL(1));
+	} else {
+		/* de-assert ip_tg_enable signal */
+		temp = I915_READ(MIPI_PORT_CTRL(port));
+		I915_WRITE(MIPI_PORT_CTRL(port), temp & ~DPI_ENABLE);
+		POSTING_READ(MIPI_PORT_CTRL(port));
+	}
 }
 
 static void intel_dsi_device_ready(struct intel_encoder *encoder)
@@ -505,6 +537,7 @@ static void intel_dsi_prepare(struct intel_encoder *intel_encoder)
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
 	struct drm_display_mode *adjusted_mode =
 		&intel_crtc->config.adjusted_mode;
+	enum pipe pipe = intel_crtc->pipe;
 	int port = PIPE_MAPPED_TO_MIPI_PORT(intel_crtc->pipe);
 	unsigned int bpp = intel_crtc->config.pipe_bpp;
 	u32 val, tmp;
diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
index 587e71f..950ab41 100644
--- a/drivers/gpu/drm/i915/intel_dsi.h
+++ b/drivers/gpu/drm/i915/intel_dsi.h
@@ -101,6 +101,7 @@ struct intel_dsi {
 	u8 clock_stop;
 
 	u8 escape_clk_div;
+	u8 dual_link;
 	u32 port_bits;
 	u32 bw_timer;
 	u32 dphy_reg;
diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
index 051bfff..d424ebc 100644
--- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
+++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
@@ -283,6 +283,7 @@ static bool generic_init(struct intel_dsi_device *dsi)
 	intel_dsi->lane_count = mipi_config->lane_cnt + 1;
 	intel_dsi->pixel_format = mipi_config->videomode_color_format << 7;
 	intel_dsi->port = 0;
+	intel_dsi->dual_link = mipi_config->dual_link;
 
 	if (intel_dsi->pixel_format == VID_MODE_FORMAT_RGB666)
 		bits_per_pixel = 18;
-- 
1.7.9.5