drm/vc4: hdmi: Enable 10/12 bpc output

The BCM2711 supports higher bpc count than just 8, so let's support it in
our driver.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215154243.540115-10-maxime@cerno.tech

Author: mripard

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -76,6 +76,17 @@
 #define VC5_HDMI_VERTB_VSPO_SHIFT		16
 #define VC5_HDMI_VERTB_VSPO_MASK		VC4_MASK(29, 16)
 
+#define VC5_HDMI_DEEP_COLOR_CONFIG_1_INIT_PACK_PHASE_SHIFT	8
+#define VC5_HDMI_DEEP_COLOR_CONFIG_1_INIT_PACK_PHASE_MASK	VC4_MASK(10, 8)
+
+#define VC5_HDMI_DEEP_COLOR_CONFIG_1_COLOR_DEPTH_SHIFT		0
+#define VC5_HDMI_DEEP_COLOR_CONFIG_1_COLOR_DEPTH_MASK		VC4_MASK(3, 0)
+
+#define VC5_HDMI_GCP_CONFIG_GCP_ENABLE		BIT(31)
+
+#define VC5_HDMI_GCP_WORD_1_GCP_SUBPACKET_BYTE_1_SHIFT	8
+#define VC5_HDMI_GCP_WORD_1_GCP_SUBPACKET_BYTE_1_MASK	VC4_MASK(15, 8)
+
 # define VC4_HD_M_SW_RST			BIT(2)
 # define VC4_HD_M_ENABLE			BIT(0)
 
@@ -186,6 +197,8 @@ static void vc4_hdmi_connector_reset(struct drm_connector *connector)
 	if (!new_state)
 		return;
 
+	new_state->base.max_bpc = 8;
+	new_state->base.max_requested_bpc = 8;
 	drm_atomic_helper_connector_tv_reset(connector);
 }
 
@@ -232,12 +245,20 @@ static int vc4_hdmi_connector_init(struct drm_device *dev,
 				    vc4_hdmi->ddc);
 	drm_connector_helper_add(connector, &vc4_hdmi_connector_helper_funcs);
 
+	/*
+	 * Some of the properties below require access to state, like bpc.
+	 * Allocate some default initial connector state with our reset helper.
+	 */
+	if (connector->funcs->reset)
+		connector->funcs->reset(connector);
+
 	/* Create and attach TV margin props to this connector. */
 	ret = drm_mode_create_tv_margin_properties(dev);
 	if (ret)
 		return ret;
 
 	drm_connector_attach_tv_margin_properties(connector);
+	drm_connector_attach_max_bpc_property(connector, 8, 12);
 
 	connector->polled = (DRM_CONNECTOR_POLL_CONNECT |
 			     DRM_CONNECTOR_POLL_DISCONNECT);
@@ -506,6 +527,7 @@ static void vc5_hdmi_csc_setup(struct vc4_hdmi *vc4_hdmi, bool enable)
 }
 
 static void vc4_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
+				 struct drm_connector_state *state,
 				 struct drm_display_mode *mode)
 {
 	bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
@@ -549,7 +571,9 @@ static void vc4_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
 	HDMI_WRITE(HDMI_VERTB0, vertb_even);
 	HDMI_WRITE(HDMI_VERTB1, vertb);
 }
+
 static void vc5_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
+				 struct drm_connector_state *state,
 				 struct drm_display_mode *mode)
 {
 	bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
@@ -569,6 +593,9 @@ static void vc5_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
 					mode->crtc_vsync_end -
 					interlaced,
 					VC4_HDMI_VERTB_VBP));
+	unsigned char gcp;
+	bool gcp_en;
+	u32 reg;
 
 	HDMI_WRITE(HDMI_VEC_INTERFACE_XBAR, 0x354021);
 	HDMI_WRITE(HDMI_HORZA,
@@ -594,6 +621,39 @@ static void vc5_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
 	HDMI_WRITE(HDMI_VERTB0, vertb_even);
 	HDMI_WRITE(HDMI_VERTB1, vertb);
 
+	switch (state->max_bpc) {
+	case 12:
+		gcp = 6;
+		gcp_en = true;
+		break;
+	case 10:
+		gcp = 5;
+		gcp_en = true;
+		break;
+	case 8:
+	default:
+		gcp = 4;
+		gcp_en = false;
+		break;
+	}
+
+	reg = HDMI_READ(HDMI_DEEP_COLOR_CONFIG_1);
+	reg &= ~(VC5_HDMI_DEEP_COLOR_CONFIG_1_INIT_PACK_PHASE_MASK |
+		 VC5_HDMI_DEEP_COLOR_CONFIG_1_COLOR_DEPTH_MASK);
+	reg |= VC4_SET_FIELD(2, VC5_HDMI_DEEP_COLOR_CONFIG_1_INIT_PACK_PHASE) |
+	       VC4_SET_FIELD(gcp, VC5_HDMI_DEEP_COLOR_CONFIG_1_COLOR_DEPTH);
+	HDMI_WRITE(HDMI_DEEP_COLOR_CONFIG_1, reg);
+
+	reg = HDMI_READ(HDMI_GCP_WORD_1);
+	reg &= ~VC5_HDMI_GCP_WORD_1_GCP_SUBPACKET_BYTE_1_MASK;
+	reg |= VC4_SET_FIELD(gcp, VC5_HDMI_GCP_WORD_1_GCP_SUBPACKET_BYTE_1);
+	HDMI_WRITE(HDMI_GCP_WORD_1, reg);
+
+	reg = HDMI_READ(HDMI_GCP_CONFIG);
+	reg &= ~VC5_HDMI_GCP_CONFIG_GCP_ENABLE;
+	reg |= gcp_en ? VC5_HDMI_GCP_CONFIG_GCP_ENABLE : 0;
+	HDMI_WRITE(HDMI_GCP_CONFIG, reg);
+
 	HDMI_WRITE(HDMI_CLOCK_STOP, 0);
 }
 
@@ -731,7 +791,7 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 		   VC4_HDMI_SCHEDULER_CONTROL_IGNORE_VSYNC_PREDICTS);
 
 	if (vc4_hdmi->variant->set_timings)
-		vc4_hdmi->variant->set_timings(vc4_hdmi, mode);
+		vc4_hdmi->variant->set_timings(vc4_hdmi, conn_state, mode);
 }
 
 static void vc4_hdmi_encoder_pre_crtc_enable(struct drm_encoder *encoder,
@@ -852,6 +912,14 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
 		pixel_rate = mode->clock * 1000;
 	}
 
+	if (conn_state->max_bpc == 12) {
+		pixel_rate = pixel_rate * 150;
+		do_div(pixel_rate, 100);
+	} else if (conn_state->max_bpc == 10) {
+		pixel_rate = pixel_rate * 125;
+		do_div(pixel_rate, 100);
+	}
+
 	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
 		pixel_rate = pixel_rate * 2;
 

drivers/gpu/drm/vc4/vc4_hdmi.h

@@ -77,6 +77,7 @@ struct vc4_hdmi_variant {
 
 	/* Callback to configure the video timings in the HDMI block */
 	void (*set_timings)(struct vc4_hdmi *vc4_hdmi,
+			    struct drm_connector_state *state,
 			    struct drm_display_mode *mode);
 
 	/* Callback to initialize the PHY according to the connector state */

drivers/gpu/drm/vc4/vc4_hdmi_regs.h

@@ -59,9 +59,12 @@ enum vc4_hdmi_field {
 	 */
 	HDMI_CTS_0,
 	HDMI_CTS_1,
+	HDMI_DEEP_COLOR_CONFIG_1,
 	HDMI_DVP_CTL,
 	HDMI_FIFO_CTL,
 	HDMI_FRAME_COUNT,
+	HDMI_GCP_CONFIG,
+	HDMI_GCP_WORD_1,
 	HDMI_HORZA,
 	HDMI_HORZB,
 	HDMI_HOTPLUG,
@@ -229,6 +232,9 @@ static const struct vc4_hdmi_register __maybe_unused vc5_hdmi_hdmi0_fields[] = {
 	VC4_HDMI_REG(HDMI_VERTB1, 0x0f8),
 	VC4_HDMI_REG(HDMI_MAI_CHANNEL_MAP, 0x09c),
 	VC4_HDMI_REG(HDMI_MAI_CONFIG, 0x0a0),
+	VC4_HDMI_REG(HDMI_DEEP_COLOR_CONFIG_1, 0x170),
+	VC4_HDMI_REG(HDMI_GCP_CONFIG, 0x178),
+	VC4_HDMI_REG(HDMI_GCP_WORD_1, 0x17c),
 	VC4_HDMI_REG(HDMI_HOTPLUG, 0x1a8),
 
 	VC5_DVP_REG(HDMI_CLOCK_STOP, 0x0bc),
@@ -305,6 +311,9 @@ static const struct vc4_hdmi_register __maybe_unused vc5_hdmi_hdmi1_fields[] = {
 	VC4_HDMI_REG(HDMI_VERTB1, 0x0f8),
 	VC4_HDMI_REG(HDMI_MAI_CHANNEL_MAP, 0x09c),
 	VC4_HDMI_REG(HDMI_MAI_CONFIG, 0x0a0),
+	VC4_HDMI_REG(HDMI_DEEP_COLOR_CONFIG_1, 0x170),
+	VC4_HDMI_REG(HDMI_GCP_CONFIG, 0x178),
+	VC4_HDMI_REG(HDMI_GCP_WORD_1, 0x17c),
 	VC4_HDMI_REG(HDMI_HOTPLUG, 0x1a8),
 
 	VC5_DVP_REG(HDMI_CLOCK_STOP, 0x0bc),