drm: rcar-du: Support multiple sources from the same VSP

On R-Car H3 ES2.0, DU channels 0 and 3 are served by two separate
pipelines from the same VSP. Support this in the DU driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>

1 files changed, 78 insertions, 11 deletions

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_kms.c b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
index 1a0a0ce..99adf53 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_kms.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
@@ -435,6 +435,81 @@ static int rcar_du_properties_init(struct rcar_du_device *rcdu)
 	return 0;
 }
 
+static int rcar_du_vsps_init(struct rcar_du_device *rcdu)
+{
+	const struct device_node *np = rcdu->dev->of_node;
+	struct of_phandle_args args;
+	struct {
+		struct device_node *np;
+		unsigned int crtcs_mask;
+	} vsps[RCAR_DU_MAX_VSPS] = { { 0, }, };
+	unsigned int vsps_count = 0;
+	unsigned int cells;
+	unsigned int i;
+	int ret;
+
+	/*
+	 * First parse the DT vsps property to populate the list of VSPs. Each
+	 * entry contains a pointer to the VSP DT node and a bitmask of the
+	 * connected DU CRTCs.
+	 */
+	cells = of_property_count_u32_elems(np, "vsps") / rcdu->num_crtcs - 1;
+	if (cells > 1)
+		return -EINVAL;
+
+	for (i = 0; i < rcdu->num_crtcs; ++i) {
+		unsigned int j;
+
+		ret = of_parse_phandle_with_fixed_args(np, "vsps", cells, i,
+						       &args);
+		if (ret < 0)
+			goto error;
+
+		/*
+		 * Add the VSP to the list or update the corresponding existing
+		 * entry if the VSP has already been added.
+		 */
+		for (j = 0; j < vsps_count; ++j) {
+			if (vsps[j].np == args.np)
+				break;
+		}
+
+		if (j < vsps_count)
+			of_node_put(args.np);
+		else
+			vsps[vsps_count++].np = args.np;
+
+		vsps[j].crtcs_mask |= BIT(i);
+
+		/* Store the VSP pointer and pipe index in the CRTC. */
+		rcdu->crtcs[i].vsp = &rcdu->vsps[j];
+		rcdu->crtcs[i].vsp_pipe = cells >= 1 ? args.args[0] : 0;
+	}
+
+	/*
+	 * Then initialize all the VSPs from the node pointers and CRTCs bitmask
+	 * computed previously.
+	 */
+	for (i = 0; i < vsps_count; ++i) {
+		struct rcar_du_vsp *vsp = &rcdu->vsps[i];
+
+		vsp->index = i;
+		vsp->dev = rcdu;
+
+		ret = rcar_du_vsp_init(vsp, vsps[i].np, vsps[i].crtcs_mask);
+		if (ret < 0)
+			goto error;
+	}
+
+	return 0;
+
+error:
+	for (i = 0; i < ARRAY_SIZE(vsps); ++i)
+		of_node_put(vsps[i].np);
+
+	return ret;
+}
+
 int rcar_du_modeset_init(struct rcar_du_device *rcdu)
 {
 	static const unsigned int mmio_offsets[] = {
@@ -504,17 +579,9 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu)
 
 	/* Initialize the compositors. */
 	if (rcar_du_has(rcdu, RCAR_DU_FEATURE_VSP1_SOURCE)) {
-		for (i = 0; i < rcdu->num_crtcs; ++i) {
-			struct rcar_du_vsp *vsp = &rcdu->vsps[i];
-
-			vsp->index = i;
-			vsp->dev = rcdu;
-			rcdu->crtcs[i].vsp = vsp;
-
-			ret = rcar_du_vsp_init(vsp);
-			if (ret < 0)
-				return ret;
-		}
+		ret = rcar_du_vsps_init(rcdu);
+		if (ret < 0)
+			return ret;
 	}
 
 	/* Create the CRTCs. */