drm/i915/icl: Program DSI clock and data lane timing params

This patch programs D-PHY timing parameters for the
clock and data lane (in escape clocks) of DSI
controller (DSI port 0 and 1).
These programmed timings would be used by DSI Controller
to calculate link transition latencies of the data and
clock lanes.

v2: Use newly defined bitfields for data and clock lane

v3 by Jani:
 - Rebase on dphy abstraction
 - Reduce local variables
 - Remove unrelated comment changes (Ville)
 - Use the same style for range checks as VLV (Ville)
 - Assign, don't OR dphy_reg contents
Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/70d491e2357f328a63b67ea3c43cb57a1d469c15.1539613303.git.jani.nikula@intel.com

drivers/gpu/drm/i915/icl_dsi.c

@@ -291,6 +291,24 @@ static void gen11_dsi_setup_dphy_timings(struct intel_encoder *encoder)
 		tmp |= intel_dsi->init_count;
 		I915_WRITE(ICL_DSI_T_INIT_MASTER(port), tmp);
 	}
+
+	/* Program DPHY clock lanes timings */
+	for_each_dsi_port(port, intel_dsi->ports) {
+		I915_WRITE(DPHY_CLK_TIMING_PARAM(port), intel_dsi->dphy_reg);
+
+		/* shadow register inside display core */
+		I915_WRITE(DSI_CLK_TIMING_PARAM(port), intel_dsi->dphy_reg);
+	}
+
+	/* Program DPHY data lanes timings */
+	for_each_dsi_port(port, intel_dsi->ports) {
+		I915_WRITE(DPHY_DATA_TIMING_PARAM(port),
+			   intel_dsi->dphy_data_lane_reg);
+
+		/* shadow register inside display core */
+		I915_WRITE(DSI_DATA_TIMING_PARAM(port),
+			   intel_dsi->dphy_data_lane_reg);
+	}
 }
 
 static void gen11_dsi_enable_port_and_phy(struct intel_encoder *encoder)

drivers/gpu/drm/i915/intel_dsi.h

@@ -85,6 +85,9 @@ struct intel_dsi {
 	u32 port_bits;
 	u32 bw_timer;
 	u32 dphy_reg;
+
+	/* data lanes dphy timing */
+	u32 dphy_data_lane_reg;
 	u32 video_frmt_cfg_bits;
 	u16 lp_byte_clk;
 

drivers/gpu/drm/i915/intel_dsi_vbt.c

@@ -510,6 +510,111 @@ int intel_dsi_vbt_get_modes(struct intel_dsi *intel_dsi)
 	return 1;
 }
 
+#define ICL_PREPARE_CNT_MAX	0x7
+#define ICL_CLK_ZERO_CNT_MAX	0xf
+#define ICL_TRAIL_CNT_MAX	0x7
+#define ICL_TCLK_PRE_CNT_MAX	0x3
+#define ICL_TCLK_POST_CNT_MAX	0x7
+#define ICL_HS_ZERO_CNT_MAX	0xf
+#define ICL_EXIT_ZERO_CNT_MAX	0x7
+
+static void icl_dphy_param_init(struct intel_dsi *intel_dsi)
+{
+	struct drm_device *dev = intel_dsi->base.base.dev;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct mipi_config *mipi_config = dev_priv->vbt.dsi.config;
+	u32 tlpx_ns;
+	u32 prepare_cnt, exit_zero_cnt, clk_zero_cnt, trail_cnt;
+	u32 ths_prepare_ns, tclk_trail_ns;
+	u32 hs_zero_cnt;
+	u32 tclk_pre_cnt, tclk_post_cnt;
+
+	tlpx_ns = intel_dsi_tlpx_ns(intel_dsi);
+
+	tclk_trail_ns = max(mipi_config->tclk_trail, mipi_config->ths_trail);
+	ths_prepare_ns = max(mipi_config->ths_prepare,
+			     mipi_config->tclk_prepare);
+
+	/*
+	 * prepare cnt in escape clocks
+	 * this field represents a hexadecimal value with a precision
+	 * of 1.2 – i.e. the most significant bit is the integer
+	 * and the least significant 2 bits are fraction bits.
+	 * so, the field can represent a range of 0.25 to 1.75
+	 */
+	prepare_cnt = DIV_ROUND_UP(ths_prepare_ns * 4, tlpx_ns);
+	if (prepare_cnt > ICL_PREPARE_CNT_MAX) {
+		DRM_DEBUG_KMS("prepare_cnt out of range (%d)\n", prepare_cnt);
+		prepare_cnt = ICL_PREPARE_CNT_MAX;
+	}
+
+	/* clk zero count in escape clocks */
+	clk_zero_cnt = DIV_ROUND_UP(mipi_config->tclk_prepare_clkzero -
+				    ths_prepare_ns, tlpx_ns);
+	if (clk_zero_cnt > ICL_CLK_ZERO_CNT_MAX) {
+		DRM_DEBUG_KMS("clk_zero_cnt out of range (%d)\n", clk_zero_cnt);
+		clk_zero_cnt = ICL_CLK_ZERO_CNT_MAX;
+	}
+
+	/* trail cnt in escape clocks*/
+	trail_cnt = DIV_ROUND_UP(tclk_trail_ns, tlpx_ns);
+	if (trail_cnt > ICL_TRAIL_CNT_MAX) {
+		DRM_DEBUG_KMS("trail_cnt out of range (%d)\n", trail_cnt);
+		trail_cnt = ICL_TRAIL_CNT_MAX;
+	}
+
+	/* tclk pre count in escape clocks */
+	tclk_pre_cnt = DIV_ROUND_UP(mipi_config->tclk_pre, tlpx_ns);
+	if (tclk_pre_cnt > ICL_TCLK_PRE_CNT_MAX) {
+		DRM_DEBUG_KMS("tclk_pre_cnt out of range (%d)\n", tclk_pre_cnt);
+		tclk_pre_cnt = ICL_TCLK_PRE_CNT_MAX;
+	}
+
+	/* tclk post count in escape clocks */
+	tclk_post_cnt = DIV_ROUND_UP(mipi_config->tclk_post, tlpx_ns);
+	if (tclk_post_cnt > ICL_TCLK_POST_CNT_MAX) {
+		DRM_DEBUG_KMS("tclk_post_cnt out of range (%d)\n", tclk_post_cnt);
+		tclk_post_cnt = ICL_TCLK_POST_CNT_MAX;
+	}
+
+	/* hs zero cnt in escape clocks */
+	hs_zero_cnt = DIV_ROUND_UP(mipi_config->ths_prepare_hszero -
+				   ths_prepare_ns, tlpx_ns);
+	if (hs_zero_cnt > ICL_HS_ZERO_CNT_MAX) {
+		DRM_DEBUG_KMS("hs_zero_cnt out of range (%d)\n", hs_zero_cnt);
+		hs_zero_cnt = ICL_HS_ZERO_CNT_MAX;
+	}
+
+	/* hs exit zero cnt in escape clocks */
+	exit_zero_cnt = DIV_ROUND_UP(mipi_config->ths_exit, tlpx_ns);
+	if (exit_zero_cnt > ICL_EXIT_ZERO_CNT_MAX) {
+		DRM_DEBUG_KMS("exit_zero_cnt out of range (%d)\n", exit_zero_cnt);
+		exit_zero_cnt = ICL_EXIT_ZERO_CNT_MAX;
+	}
+
+	/* clock lane dphy timings */
+	intel_dsi->dphy_reg = (CLK_PREPARE_OVERRIDE |
+			       CLK_PREPARE(prepare_cnt) |
+			       CLK_ZERO_OVERRIDE |
+			       CLK_ZERO(clk_zero_cnt) |
+			       CLK_PRE_OVERRIDE |
+			       CLK_PRE(tclk_pre_cnt) |
+			       CLK_POST_OVERRIDE |
+			       CLK_POST(tclk_post_cnt) |
+			       CLK_TRAIL_OVERRIDE |
+			       CLK_TRAIL(trail_cnt));
+
+	/* data lanes dphy timings */
+	intel_dsi->dphy_data_lane_reg = (HS_PREPARE_OVERRIDE |
+					 HS_PREPARE(prepare_cnt) |
+					 HS_ZERO_OVERRIDE |
+					 HS_ZERO(hs_zero_cnt) |
+					 HS_TRAIL_OVERRIDE |
+					 HS_TRAIL(trail_cnt) |
+					 HS_EXIT_OVERRIDE |
+					 HS_EXIT(exit_zero_cnt));
+}
+
 static void vlv_dphy_param_init(struct intel_dsi *intel_dsi)
 {
 	struct drm_device *dev = intel_dsi->base.base.dev;
@@ -743,7 +848,10 @@ bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
 
 	intel_dsi->burst_mode_ratio = burst_mode_ratio;
 
-	vlv_dphy_param_init(intel_dsi);
+	if (IS_ICELAKE(dev_priv))
+		icl_dphy_param_init(intel_dsi);
+	else
+		vlv_dphy_param_init(intel_dsi);
 
 	DRM_DEBUG_KMS("Pclk %d\n", intel_dsi->pclk);
 	DRM_DEBUG_KMS("Pixel overlap %d\n", intel_dsi->pixel_overlap);