Thread (1 message) 1 message, 1 author, 2019-01-10

Re: [PATCH 1/9] drm/mediatek: recalculate hdmi phy clock of MT2701 by querying hardware

From: CK Hu <hidden>
Date: 2019-01-10 01:47:29
Also in: dri-devel, linux-clk, linux-mediatek, lkml

Hi, Chunhui:


On Fri, 2019-01-04 at 15:03 +0800, chunhui dai wrote:
quoted hunk
Recalculate the rate of this clock, by querying hardware.

Signed-off-by: chunhui dai <redacted>
---
 drivers/gpu/drm/mediatek/mtk_hdmi_phy.c        |  7 ++--
 drivers/gpu/drm/mediatek/mtk_hdmi_phy.h        |  3 +-
 drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c | 49 ++++++++++++++++++++++++++
 drivers/gpu/drm/mediatek/mtk_mt8173_hdmi_phy.c |  8 +++++
 4 files changed, 61 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c
index 4ef9c57..79e737d 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c
@@ -29,12 +29,11 @@ long mtk_hdmi_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 	return rate;
 }
 
-unsigned long mtk_hdmi_pll_recalc_rate(struct clk_hw *hw,
-				       unsigned long parent_rate)
+u32 mtk_hdmi_phy_read(struct mtk_hdmi_phy *hdmi_phy, u32 offset)
 {
-	struct mtk_hdmi_phy *hdmi_phy = to_mtk_hdmi_phy(hw);
+	void __iomem *reg = hdmi_phy->regs + offset;
 
-	return hdmi_phy->pll_rate;
+	return readl(reg);
reg is used only once, so

return readl(hdmi_phy->regs + offset);
quoted hunk
 }
 
 void mtk_hdmi_phy_clear_bits(struct mtk_hdmi_phy *hdmi_phy, u32 offset,
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h
index f39b1fc..fdad8b1 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h
@@ -41,6 +41,7 @@ struct mtk_hdmi_phy {
 	unsigned int ibias_up;
 };
 
+u32 mtk_hdmi_phy_read(struct mtk_hdmi_phy *hdmi_phy, u32 offset);
 void mtk_hdmi_phy_clear_bits(struct mtk_hdmi_phy *hdmi_phy, u32 offset,
 			     u32 bits);
 void mtk_hdmi_phy_set_bits(struct mtk_hdmi_phy *hdmi_phy, u32 offset,
@@ -50,8 +51,6 @@ void mtk_hdmi_phy_mask(struct mtk_hdmi_phy *hdmi_phy, u32 offset,
 struct mtk_hdmi_phy *to_mtk_hdmi_phy(struct clk_hw *hw);
 long mtk_hdmi_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 			     unsigned long *parent_rate);
-unsigned long mtk_hdmi_pll_recalc_rate(struct clk_hw *hw,
-				       unsigned long parent_rate);
 
 extern struct platform_driver mtk_hdmi_phy_driver;
 extern struct mtk_hdmi_phy_conf mtk_hdmi_phy_8173_conf;
diff --git a/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c b/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c
index fcc42dc..b5ed6b7 100644
--- a/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c
+++ b/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c
@@ -153,6 +153,55 @@ static int mtk_hdmi_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 			  RG_HDMITX_DRV_IBIAS_MASK);
 	return 0;
 }
+static unsigned long mtk_hdmi_pll_recalc_rate(struct clk_hw *hw,
+				       unsigned long parent_rate)
+{
+	struct mtk_hdmi_phy *hdmi_phy = to_mtk_hdmi_phy(hw);
+	unsigned long out_rate, val;
+
+	val = (mtk_hdmi_phy_read(hdmi_phy, HDMI_CON6)
+			& RG_HTPLL_PREDIV_MASK) >> RG_HTPLL_PREDIV;
+	switch (val) {
+	case 0x00:
+		out_rate = parent_rate;
+		break;
+	case 0x01:
+		out_rate = parent_rate / 2;
+		break;
+	default:
+		out_rate = parent_rate / 4;
+		break;
If the val would not be 3, maybe out_rate could be calculate as

out_rate >>= val;
+	}
+
+	val = (mtk_hdmi_phy_read(hdmi_phy, HDMI_CON6)
+			& RG_HTPLL_FBKDIV_MASK) >> RG_HTPLL_FBKDIV;
+	out_rate = out_rate * (val + 1) * 2;
out_rate *= (val + 1) * 2;
+	val = (mtk_hdmi_phy_read(hdmi_phy, HDMI_CON2)
+			& RG_HDMITX_TX_POSDIV_MASK) >> RG_HDMITX_TX_POSDIV;
+	switch (val) {
+	case 0x00:
+		out_rate = out_rate;
+		break;
+	case 0x01:
+		out_rate = out_rate / 2;
+		break;
+	case 0x02:
+		out_rate = out_rate / 4;
+		break;
+	case 0x03:
+		out_rate = out_rate / 8;
+		break;
+	default:
+		break;
+	}
out_rate >>= val;

Regards,
CK
quoted hunk
+
+	if (mtk_hdmi_phy_read(hdmi_phy, HDMI_CON2) & RG_HDMITX_EN_TX_POSDIV)
+		out_rate = out_rate / 5;
+
+	hdmi_phy->pll_rate = out_rate;
+
+	return hdmi_phy->pll_rate;
+}
 
 static const struct clk_ops mtk_hdmi_phy_pll_ops = {
 	.prepare = mtk_hdmi_pll_prepare,
diff --git a/drivers/gpu/drm/mediatek/mtk_mt8173_hdmi_phy.c b/drivers/gpu/drm/mediatek/mtk_mt8173_hdmi_phy.c
index ed5916b..cb23c1e 100644
--- a/drivers/gpu/drm/mediatek/mtk_mt8173_hdmi_phy.c
+++ b/drivers/gpu/drm/mediatek/mtk_mt8173_hdmi_phy.c
@@ -285,6 +285,14 @@ static int mtk_hdmi_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 	return 0;
 }
 
+static unsigned long mtk_hdmi_pll_recalc_rate(struct clk_hw *hw,
+				       unsigned long parent_rate)
+{
+	struct mtk_hdmi_phy *hdmi_phy = to_mtk_hdmi_phy(hw);
+
+	return hdmi_phy->pll_rate;
+}
+
 static const struct clk_ops mtk_hdmi_phy_pll_ops = {
 	.prepare = mtk_hdmi_pll_prepare,
 	.unprepare = mtk_hdmi_pll_unprepare,


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