From 1dd22d945a99fa35e387e01101c758ae7be3d9a4 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Tue, 15 Dec 2020 16:42:40 +0100
Subject: [PATCH] drm/vc4: hdmi: Store pixel frequency in the connector
 state

The pixel rate is for now quite simple to compute, but with more features
(30 and 36 bits output, YUV output, etc.) will depend on a bunch of
connectors properties.

Let's store the rate we have to run the pixel clock at in our custom
connector state, and compute it in atomic_check.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 26 +++++++++++++++++++++++++-
 drivers/gpu/drm/vc4/vc4_hdmi.h |  1 +
 2 files changed, 26 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -245,6 +245,7 @@ vc4_hdmi_connector_duplicate_state(struc
 	if (!new_state)
 		return NULL;
 
+	new_state->pixel_rate = vc4_state->pixel_rate;
 	__drm_atomic_helper_connector_duplicate_state(connector, &new_state->base);
 
 	return &new_state->base;
@@ -671,9 +672,29 @@ static void vc4_hdmi_recenter_fifo(struc
 		  "VC4_HDMI_FIFO_CTL_RECENTER_DONE");
 }
 
+static struct drm_connector_state *
+vc4_hdmi_encoder_get_connector_state(struct drm_encoder *encoder,
+				     struct drm_atomic_state *state)
+{
+	struct drm_connector_state *conn_state;
+	struct drm_connector *connector;
+	unsigned int i;
+
+	for_each_new_connector_in_state(state, connector, conn_state, i) {
+		if (conn_state->best_encoder == encoder)
+			return conn_state;
+	}
+
+	return NULL;
+}
+
 static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 						struct drm_atomic_state *state)
 {
+	struct drm_connector_state *conn_state =
+		vc4_hdmi_encoder_get_connector_state(encoder, state);
+	struct vc4_hdmi_connector_state *vc4_conn_state =
+		conn_state_to_vc4_hdmi_conn_state(conn_state);
 	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	unsigned long pixel_rate, hsm_rate;
@@ -685,7 +706,7 @@ static void vc4_hdmi_encoder_pre_crtc_co
 		return;
 	}
 
-	pixel_rate = mode->clock * 1000 * ((mode->flags & DRM_MODE_FLAG_DBLCLK) ? 2 : 1);
+	pixel_rate = vc4_conn_state->pixel_rate;
 	ret = clk_set_rate(vc4_hdmi->pixel_clock, pixel_rate);
 	if (ret) {
 		DRM_ERROR("Failed to set pixel clock rate: %d\n", ret);
@@ -847,6 +868,7 @@ static int vc4_hdmi_encoder_atomic_check
 					 struct drm_crtc_state *crtc_state,
 					 struct drm_connector_state *conn_state)
 {
+	struct vc4_hdmi_connector_state *vc4_state = conn_state_to_vc4_hdmi_conn_state(conn_state);
 	struct drm_display_mode *mode = &crtc_state->adjusted_mode;
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	unsigned long long pixel_rate = mode->clock * 1000;
@@ -878,6 +900,8 @@ static int vc4_hdmi_encoder_atomic_check
 	if (pixel_rate > vc4_hdmi->variant->max_pixel_clock)
 		return -EINVAL;
 
+	vc4_state->pixel_rate = pixel_rate;
+
 	return 0;
 }
 
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -189,6 +189,7 @@ encoder_to_vc4_hdmi(struct drm_encoder *
 
 struct vc4_hdmi_connector_state {
 	struct drm_connector_state	base;
+	unsigned long long		pixel_rate;
 };
 
 static inline struct vc4_hdmi_connector_state *
