[PATCH v2 1/5] drm/rockchip: vop2: Improve display modes handling on RK3588 HDMI1

[Cristian Ciocaltea]

The RK3588 specific implementation is currently quite limited in terms
of handling the full range of display modes supported by the connected
screens, e.g. 2560x1440 at 75Hz, 2048x1152 at 60Hz, 1024x768 at 60Hz are just a
few of them.

Additionally, it doesn't cope well with non-integer refresh rates like
59.94, 29.97, 23.98, etc.

Make use of HDMI1 PHY PLL as a more accurate DCLK source to handle
all display modes up to 4K at 60Hz.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
---
 drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
index afc946ead87091373605e59dbca281a9e91bea57..14e039e9143ab855f32c392c5b097b97bcba70b8 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
@@ -216,6 +216,7 @@ struct vop2 {
 	struct clk *aclk;
 	struct clk *pclk;
 	struct clk *pll_hdmiphy0;
+	struct clk *pll_hdmiphy1;
 
 	/* optional internal rgb encoder */
 	struct rockchip_rgb *rgb;
@@ -2270,11 +2271,14 @@ static void vop2_crtc_atomic_enable(struct drm_crtc *crtc,
 	 * Switch to HDMI PHY PLL as DCLK source for display modes up
 	 * to 4K at 60Hz, if available, otherwise keep using the system CRU.
 	 */
-	if (vop2->pll_hdmiphy0 && clock <= VOP2_MAX_DCLK_RATE) {
+	if ((vop2->pll_hdmiphy0 || vop2->pll_hdmiphy1) && clock <= VOP2_MAX_DCLK_RATE) {
 		drm_for_each_encoder_mask(encoder, crtc->dev, crtc_state->encoder_mask) {
 			struct rockchip_encoder *rkencoder = to_rockchip_encoder(encoder);
 
 			if (rkencoder->crtc_endpoint_id == ROCKCHIP_VOP2_EP_HDMI0) {
+				if (!vop2->pll_hdmiphy0)
+					break;
+
 				if (!vp->dclk_src)
 					vp->dclk_src = clk_get_parent(vp->dclk);
 
@@ -2284,6 +2288,20 @@ static void vop2_crtc_atomic_enable(struct drm_crtc *crtc,
 						 "Could not switch to HDMI0 PHY PLL: %d\n", ret);
 				break;
 			}
+
+			if (rkencoder->crtc_endpoint_id == ROCKCHIP_VOP2_EP_HDMI1) {
+				if (!vop2->pll_hdmiphy1)
+					break;
+
+				if (!vp->dclk_src)
+					vp->dclk_src = clk_get_parent(vp->dclk);
+
+				ret = clk_set_parent(vp->dclk, vop2->pll_hdmiphy1);
+				if (ret < 0)
+					drm_warn(vop2->drm,
+						 "Could not switch to HDMI1 PHY PLL: %d\n", ret);
+				break;
+			}
 		}
 	}
 
@@ -3733,6 +3751,11 @@ static int vop2_bind(struct device *dev, struct device *master, void *data)
 		return PTR_ERR(vop2->pll_hdmiphy0);
 	}
 
+	vop2->pll_hdmiphy1 = devm_clk_get_optional(vop2->dev, "pll_hdmiphy1");
+	if (IS_ERR(vop2->pll_hdmiphy1))
+		return dev_err_probe(drm->dev, PTR_ERR(vop2->pll_hdmiphy1),
+				     "failed to get pll_hdmiphy1\n");
+
 	vop2->irq = platform_get_irq(pdev, 0);
 	if (vop2->irq < 0) {
 		drm_err(vop2->drm, "cannot find irq for vop2\n");

-- 
2.48.1