drm/i915/bxt: DSI disable and post-disable

This patch contains changes to support DSI disble sequence in BXT.
The changes are:
1. BXT specific changes in clear_device_ready function.
2. BXT specific changes in DSI disable and post-disable functions.
3. Add a new function to reset BXT Dphy clock and dividers
   (bxt_dsi_reset_clocks).
4. Moved some part of the vlv clock reset code, in a new function
   (vlv_dsi_reset_clocks) maintaining the exact same sequence.
5. Wrapper function to call corresponding reset clock function.

v2: Fixed Jani's review comments.

v3: Removed the GET_DSI_PORT_CTRL Macro for consistency with earlier
    implementations as per Jani's suggestion.

Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_dsi.c

@@ -417,12 +417,15 @@ static void intel_dsi_port_disable(struct intel_encoder *encoder)
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
 	enum port port;
 	u32 temp;
+	u32 port_ctrl;
 
 	for_each_dsi_port(port, intel_dsi->ports) {
 		/* 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));
+		port_ctrl = IS_BROXTON(dev) ? BXT_MIPI_PORT_CTRL(port) :
+						MIPI_PORT_CTRL(port);
+		temp = I915_READ(port_ctrl);
+		I915_WRITE(port_ctrl, temp & ~DPI_ENABLE);
+		POSTING_READ(port_ctrl);
 	}
 }
 
@@ -554,12 +557,7 @@ static void intel_dsi_disable(struct intel_encoder *encoder)
 		/* Panel commands can be sent when clock is in LP11 */
 		I915_WRITE(MIPI_DEVICE_READY(port), 0x0);
 
-		temp = I915_READ(MIPI_CTRL(port));
-		temp &= ~ESCAPE_CLOCK_DIVIDER_MASK;
-		I915_WRITE(MIPI_CTRL(port), temp |
-			   intel_dsi->escape_clk_div <<
-			   ESCAPE_CLOCK_DIVIDER_SHIFT);
-
+		intel_dsi_reset_clocks(encoder, port);
 		I915_WRITE(MIPI_EOT_DISABLE(port), CLOCKSTOP);
 
 		temp = I915_READ(MIPI_DSI_FUNC_PRG(port));
@@ -578,10 +576,12 @@ static void intel_dsi_disable(struct intel_encoder *encoder)
 
 static void intel_dsi_clear_device_ready(struct intel_encoder *encoder)
 {
+	struct drm_device *dev = encoder->base.dev;
 	struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
 	enum port port;
 	u32 val;
+	u32 port_ctrl = 0;
 
 	DRM_DEBUG_KMS("\n");
 	for_each_dsi_port(port, intel_dsi->ports) {
@@ -598,18 +598,22 @@ static void intel_dsi_clear_device_ready(struct intel_encoder *encoder)
 							ULPS_STATE_ENTER);
 		usleep_range(2000, 2500);
 
+		if (IS_BROXTON(dev))
+			port_ctrl = BXT_MIPI_PORT_CTRL(port);
+		else if (IS_VALLEYVIEW(dev))
+			/* Common bit for both MIPI Port A & MIPI Port C */
+			port_ctrl = MIPI_PORT_CTRL(PORT_A);
+
 		/* Wait till Clock lanes are in LP-00 state for MIPI Port A
 		 * only. MIPI Port C has no similar bit for checking
 		 */
-		if (wait_for(((I915_READ(MIPI_PORT_CTRL(PORT_A)) & AFE_LATCHOUT)
-							== 0x00000), 30))
+		if (wait_for(((I915_READ(port_ctrl) & AFE_LATCHOUT)
+						== 0x00000), 30))
 			DRM_ERROR("DSI LP not going Low\n");
 
-		/* Disable MIPI PHY transparent latch
-		 * Common bit for both MIPI Port A & MIPI Port C
-		 */
-		val = I915_READ(MIPI_PORT_CTRL(PORT_A));
-		I915_WRITE(MIPI_PORT_CTRL(PORT_A), val & ~LP_OUTPUT_HOLD);
+		/* Disable MIPI PHY transparent latch */
+		val = I915_READ(port_ctrl);
+		I915_WRITE(port_ctrl, val & ~LP_OUTPUT_HOLD);
 		usleep_range(1000, 1500);
 
 		I915_WRITE(MIPI_DEVICE_READY(port), 0x00);

drivers/gpu/drm/i915/intel_dsi.h

@@ -127,6 +127,8 @@ static inline struct intel_dsi *enc_to_intel_dsi(struct drm_encoder *encoder)
 extern void intel_enable_dsi_pll(struct intel_encoder *encoder);
 extern void intel_disable_dsi_pll(struct intel_encoder *encoder);
 extern u32 vlv_get_dsi_pclk(struct intel_encoder *encoder, int pipe_bpp);
+extern void intel_dsi_reset_clocks(struct intel_encoder *encoder,
+							enum port port);
 
 struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id);
 

drivers/gpu/drm/i915/intel_dsi_pll.c

@@ -384,6 +384,19 @@ u32 vlv_get_dsi_pclk(struct intel_encoder *encoder, int pipe_bpp)
 	return pclk;
 }
 
+void vlv_dsi_reset_clocks(struct intel_encoder *encoder, enum port port)
+{
+	u32 temp;
+	struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+
+	temp = I915_READ(MIPI_CTRL(port));
+	temp &= ~ESCAPE_CLOCK_DIVIDER_MASK;
+	I915_WRITE(MIPI_CTRL(port), temp |
+			intel_dsi->escape_clk_div <<
+			ESCAPE_CLOCK_DIVIDER_SHIFT);
+}
+
 /* Program BXT Mipi clocks and dividers */
 static void bxt_dsi_program_clocks(struct drm_device *dev, enum port port)
 {
@@ -528,3 +541,29 @@ void intel_disable_dsi_pll(struct intel_encoder *encoder)
 	else if (IS_BROXTON(dev))
 		bxt_disable_dsi_pll(encoder);
 }
+
+void bxt_dsi_reset_clocks(struct intel_encoder *encoder, enum port port)
+{
+	u32 tmp;
+	struct drm_device *dev = encoder->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	/* Clear old configurations */
+	tmp = I915_READ(BXT_MIPI_CLOCK_CTL);
+	tmp &= ~(BXT_MIPI_TX_ESCLK_FIXDIV_MASK(port));
+	tmp &= ~(BXT_MIPI_RX_ESCLK_FIXDIV_MASK(port));
+	tmp &= ~(BXT_MIPI_ESCLK_VAR_DIV_MASK(port));
+	tmp &= ~(BXT_MIPI_DPHY_DIVIDER_MASK(port));
+	I915_WRITE(BXT_MIPI_CLOCK_CTL, tmp);
+	I915_WRITE(MIPI_EOT_DISABLE(port), CLOCKSTOP);
+}
+
+void intel_dsi_reset_clocks(struct intel_encoder *encoder, enum port port)
+{
+	struct drm_device *dev = encoder->base.dev;
+
+	if (IS_BROXTON(dev))
+		bxt_dsi_reset_clocks(encoder, port);
+	else if (IS_VALLEYVIEW(dev))
+		vlv_dsi_reset_clocks(encoder, port);
+}