openwrt/target/linux/bcm27xx/patches-5.4/950-0275-drm-vc4-Query-firmware-for-custom-HDMI-mode.patch

From 6402d9c21c9b144d528c3248607589db94ecbce0 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.org>
Date: Wed, 3 Jul 2019 17:44:53 +0100
Subject: [PATCH] drm/vc4: Query firmware for custom HDMI mode

Allow custom HDMI modes to be specified from config.txt,
and these then override EDID parsing.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
---
 drivers/gpu/drm/vc4/vc4_firmware_kms.c | 130 ++++++++++++++-----------
 1 file changed, 75 insertions(+), 55 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_firmware_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_firmware_kms.c
@@ -1066,6 +1066,56 @@ vc4_fkms_connector_detect(struct drm_con
 	return connector_status_connected;
 }
 
+/* Queries the firmware to populate a drm_mode structure for this display */
+static int vc4_fkms_get_fw_mode(struct vc4_fkms_connector *fkms_connector,
+				struct drm_display_mode *mode)
+{
+	struct vc4_dev *vc4 = fkms_connector->vc4_dev;
+	struct set_timings timings = { 0 };
+	int ret;
+
+	timings.display = fkms_connector->display_number;
+
+	ret = rpi_firmware_property(vc4->firmware,
+				    RPI_FIRMWARE_GET_DISPLAY_TIMING, &timings,
+				    sizeof(timings));
+	if (ret || !timings.clock)
+		/* No mode returned - abort */
+		return -1;
+
+	/* Equivalent to DRM_MODE macro. */
+	memset(mode, 0, sizeof(*mode));
+	strncpy(mode->name, "FIXED_MODE", sizeof(mode->name));
+	mode->status = 0;
+	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
+	mode->clock = timings.clock;
+	mode->hdisplay = timings.hdisplay;
+	mode->hsync_start = timings.hsync_start;
+	mode->hsync_end = timings.hsync_end;
+	mode->htotal = timings.htotal;
+	mode->hskew = 0;
+	mode->vdisplay = timings.vdisplay;
+	mode->vsync_start = timings.vsync_start;
+	mode->vsync_end = timings.vsync_end;
+	mode->vtotal = timings.vtotal;
+	mode->vscan = timings.vscan;
+
+	if (timings.flags & TIMINGS_FLAGS_H_SYNC_POS)
+		mode->flags |= DRM_MODE_FLAG_PHSYNC;
+	else
+		mode->flags |= DRM_MODE_FLAG_NHSYNC;
+
+	if (timings.flags & TIMINGS_FLAGS_V_SYNC_POS)
+		mode->flags |= DRM_MODE_FLAG_PVSYNC;
+	else
+		mode->flags |= DRM_MODE_FLAG_NVSYNC;
+
+	if (timings.flags & TIMINGS_FLAGS_INTERLACE)
+		mode->flags |= DRM_MODE_FLAG_INTERLACE;
+
+	return 0;
+}
+
 static int vc4_fkms_get_edid_block(void *data, u8 *buf, unsigned int block,
 				   size_t len)
 {
@@ -1094,25 +1144,35 @@ static int vc4_fkms_connector_get_modes(
 					to_vc4_fkms_connector(connector);
 	struct drm_encoder *encoder = fkms_connector->encoder;
 	struct vc4_fkms_encoder *vc4_encoder = to_vc4_fkms_encoder(encoder);
-	int ret = 0;
+	struct drm_display_mode fw_mode;
+	struct drm_display_mode *mode;
 	struct edid *edid;
+	int num_modes;
 
-	edid = drm_do_get_edid(connector, vc4_fkms_get_edid_block,
-			       fkms_connector);
+	if (!vc4_fkms_get_fw_mode(fkms_connector, &fw_mode)) {
+		drm_mode_debug_printmodeline(&fw_mode);
+		mode = drm_mode_duplicate(connector->dev,
+					  &fw_mode);
+		drm_mode_probed_add(connector, mode);
+		num_modes = 1;	/* 1 mode */
+	} else {
+		edid = drm_do_get_edid(connector, vc4_fkms_get_edid_block,
+				       fkms_connector);
 
-	/* FIXME: Can we do CEC?
-	 * cec_s_phys_addr_from_edid(vc4->hdmi->cec_adap, edid);
-	 * if (!edid)
-	 *	return -ENODEV;
-	 */
-
-	vc4_encoder->hdmi_monitor = drm_detect_hdmi_monitor(edid);
-
-	drm_connector_update_edid_property(connector, edid);
-	ret = drm_add_edid_modes(connector, edid);
-	kfree(edid);
+		/* FIXME: Can we do CEC?
+		 * cec_s_phys_addr_from_edid(vc4->hdmi->cec_adap, edid);
+		 * if (!edid)
+		 *	return -ENODEV;
+		 */
+
+		vc4_encoder->hdmi_monitor = drm_detect_hdmi_monitor(edid);
+
+		drm_connector_update_edid_property(connector, edid);
+		num_modes = drm_add_edid_modes(connector, edid);
+		kfree(edid);
+	}
 
-	return ret;
+	return num_modes;
 }
 
 /* This is the DSI panel resolution. Use this as a default should the firmware
@@ -1130,55 +1190,15 @@ static int vc4_fkms_lcd_connector_get_mo
 {
 	struct vc4_fkms_connector *fkms_connector =
 					to_vc4_fkms_connector(connector);
-	struct vc4_dev *vc4 = fkms_connector->vc4_dev;
 	struct drm_display_mode *mode;
-	struct mailbox_set_mode mb = {
-		.tag1 = { RPI_FIRMWARE_GET_DISPLAY_TIMING,
-			  sizeof(struct set_timings), 0},
-		.timings = { .display = fkms_connector->display_number },
-	};
 	struct drm_display_mode fw_mode;
-	int ret = 0;
-
-	ret = rpi_firmware_property_list(vc4->firmware, &mb, sizeof(mb));
-	if (!ret) {
-		/* Equivalent to DRM_MODE macro. */
-		memset(&fw_mode, 0, sizeof(fw_mode));
-		strncpy(fw_mode.name, "LCD_MODE", sizeof(fw_mode.name));
-		fw_mode.status = 0;
-		fw_mode.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
-		fw_mode.clock = mb.timings.clock;
-		fw_mode.hdisplay = mb.timings.hdisplay;
-		fw_mode.hsync_start = mb.timings.hsync_start;
-		fw_mode.hsync_end = mb.timings.hsync_end;
-		fw_mode.htotal = mb.timings.htotal;
-		fw_mode.hskew = 0;
-		fw_mode.vdisplay = mb.timings.vdisplay;
-		fw_mode.vsync_start = mb.timings.vsync_start;
-		fw_mode.vsync_end = mb.timings.vsync_end;
-		fw_mode.vtotal = mb.timings.vtotal;
-		fw_mode.vscan = mb.timings.vscan;
-		if (mb.timings.flags & TIMINGS_FLAGS_H_SYNC_POS)
-			fw_mode.flags |= DRM_MODE_FLAG_PHSYNC;
-		else
-			fw_mode.flags |= DRM_MODE_FLAG_NHSYNC;
-		if (mb.timings.flags & TIMINGS_FLAGS_V_SYNC_POS)
-			fw_mode.flags |= DRM_MODE_FLAG_PVSYNC;
-		else
-			fw_mode.flags |= DRM_MODE_FLAG_NVSYNC;
-		if (mb.timings.flags & TIMINGS_FLAGS_V_SYNC_POS)
-			fw_mode.flags |= DRM_MODE_FLAG_PVSYNC;
-		else
-			fw_mode.flags |= DRM_MODE_FLAG_NVSYNC;
-		if (mb.timings.flags & TIMINGS_FLAGS_INTERLACE)
-			fw_mode.flags |= DRM_MODE_FLAG_INTERLACE;
 
+	if (!vc4_fkms_get_fw_mode(fkms_connector, &fw_mode) && fw_mode.clock)
 		mode = drm_mode_duplicate(connector->dev,
 					  &fw_mode);
-	} else {
+	else
 		mode = drm_mode_duplicate(connector->dev,
 					  &lcd_mode);
-	}
 
 	if (!mode) {
 		DRM_ERROR("Failed to create a new display mode\n");