[d-kernel] [PATCH 6/7] drm/rockchip: vop2: Improve display modes handling on RK3588 HDMI1

[Daniil Gnusarev <gnusarevda@basealt.ru>]

From: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>

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@75Hz, 2048x1152@60Hz, 1024x768@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@60Hz.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20250223-vop2-hdmi1-disp-modes-v2-1-f4cec5e06fbe@collabora.com
(cherry picked from commit f8dd7fc9ba88bc4a6ea85269287a51fb756440e2)
Signed-off-by: Daniil Gnusarev <gnusarevda@basealt.ru>
---
 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 a551458ad4340..221b8e47f4f8b 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
@@ -213,6 +213,7 @@ struct vop2 {
 	struct clk *aclk;
 	struct clk *pclk;
 	struct clk *pll_hdmiphy0;
+	struct clk *pll_hdmiphy1;
 
 	/* optional internal rgb encoder */
 	struct rockchip_rgb *rgb;
@@ -2082,11 +2083,14 @@ static void vop2_crtc_atomic_enable(struct drm_crtc *crtc,
 	 * Switch to HDMI PHY PLL as DCLK source for display modes up
 	 * to 4K@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);
 
@@ -2096,6 +2100,20 @@ 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;
+			}
 		}
 	}
 
@@ -3276,6 +3294,11 @@ 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");
-- 
2.42.2