drm/meson: vclk: add support for YUV420 setup

This patch adds clocking support for the YUV420 output from the
Amlogic Meson SoCs Video Processing Unit to the HDMI Controller.

The YUV420 is obtained by generating a YUV444 pixel stream like
the classic HDMI display modes, but then the Video Encoder output
can be configured to down-sample the YUV444 pixel stream to a YUV420
stream.

This mode needs a different clock generation scheme since the TMDS PHY
clock must match the 10x ratio with the YUV420 pixel clock, but
the video encoder must run at 2x the pixel clock.

This patch adds the TMDS PHY clock value in all the video clock setup
in order to better support these specific uses cases and switch
to the Common Clock framework for clocks handling in the future.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Jernej Škrabec <jernej.skrabec@siol.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304104052.17196-11-narmstrong@baylibre.com

1 files changed, 71 insertions, 22 deletions

diff --git a/drivers/gpu/drm/meson/meson_vclk.c b/drivers/gpu/drm/meson/meson_vclk.c
index f690793ae2d5..fdf26dac9fa8 100644
--- a/drivers/gpu/drm/meson/meson_vclk.c
+++ b/drivers/gpu/drm/meson/meson_vclk.c
@@ -354,12 +354,17 @@ enum {
 /* 2970 /1 /1 /1 /5 /2  => /1 /1 */
 	MESON_VCLK_HDMI_297000,
 /* 5940 /1 /1 /2 /5 /1  => /1 /1 */
-	MESON_VCLK_HDMI_594000
+	MESON_VCLK_HDMI_594000,
+/* 2970 /1 /1 /1 /5 /1  => /1 /2 */
+	MESON_VCLK_HDMI_594000_YUV420,
 };
 
 struct meson_vclk_params {
+	unsigned int pll_freq;
+	unsigned int phy_freq;
+	unsigned int vclk_freq;
+	unsigned int venc_freq;
 	unsigned int pixel_freq;
-	unsigned int pll_base_freq;
 	unsigned int pll_od1;
 	unsigned int pll_od2;
 	unsigned int pll_od3;
@@ -367,8 +372,11 @@ struct meson_vclk_params {
 	unsigned int vclk_div;
 } params[] = {
 	[MESON_VCLK_HDMI_ENCI_54000] = {
+		.pll_freq = 4320000,
+		.phy_freq = 270000,
+		.vclk_freq = 54000,
+		.venc_freq = 54000,
 		.pixel_freq = 54000,
-		.pll_base_freq = 4320000,
 		.pll_od1 = 4,
 		.pll_od2 = 4,
 		.pll_od3 = 1,
@@ -376,8 +384,11 @@ struct meson_vclk_params {
 		.vclk_div = 1,
 	},
 	[MESON_VCLK_HDMI_DDR_54000] = {
-		.pixel_freq = 54000,
-		.pll_base_freq = 4320000,
+		.pll_freq = 4320000,
+		.phy_freq = 270000,
+		.vclk_freq = 54000,
+		.venc_freq = 54000,
+		.pixel_freq = 27000,
 		.pll_od1 = 4,
 		.pll_od2 = 4,
 		.pll_od3 = 1,
@@ -385,8 +396,11 @@ struct meson_vclk_params {
 		.vclk_div = 1,
 	},
 	[MESON_VCLK_HDMI_DDR_148500] = {
-		.pixel_freq = 148500,
-		.pll_base_freq = 2970000,
+		.pll_freq = 2970000,
+		.phy_freq = 742500,
+		.vclk_freq = 148500,
+		.venc_freq = 148500,
+		.pixel_freq = 74250,
 		.pll_od1 = 4,
 		.pll_od2 = 1,
 		.pll_od3 = 1,
@@ -394,8 +408,11 @@ struct meson_vclk_params {
 		.vclk_div = 1,
 	},
 	[MESON_VCLK_HDMI_74250] = {
+		.pll_freq = 2970000,
+		.phy_freq = 742500,
+		.vclk_freq = 74250,
+		.venc_freq = 74250,
 		.pixel_freq = 74250,
-		.pll_base_freq = 2970000,
 		.pll_od1 = 2,
 		.pll_od2 = 2,
 		.pll_od3 = 2,
@@ -403,8 +420,11 @@ struct meson_vclk_params {
 		.vclk_div = 1,
 	},
 	[MESON_VCLK_HDMI_148500] = {
+		.pll_freq = 2970000,
+		.phy_freq = 1485000,
+		.vclk_freq = 148500,
+		.venc_freq = 148500,
 		.pixel_freq = 148500,
-		.pll_base_freq = 2970000,
 		.pll_od1 = 1,
 		.pll_od2 = 2,
 		.pll_od3 = 2,
@@ -412,8 +432,11 @@ struct meson_vclk_params {
 		.vclk_div = 1,
 	},
 	[MESON_VCLK_HDMI_297000] = {
+		.pll_freq = 5940000,
+		.phy_freq = 2970000,
+		.venc_freq = 297000,
+		.vclk_freq = 297000,
 		.pixel_freq = 297000,
-		.pll_base_freq = 5940000,
 		.pll_od1 = 2,
 		.pll_od2 = 1,
 		.pll_od3 = 1,
@@ -421,14 +444,29 @@ struct meson_vclk_params {
 		.vclk_div = 2,
 	},
 	[MESON_VCLK_HDMI_594000] = {
+		.pll_freq = 5940000,
+		.phy_freq = 5940000,
+		.venc_freq = 594000,
+		.vclk_freq = 594000,
 		.pixel_freq = 594000,
-		.pll_base_freq = 5940000,
 		.pll_od1 = 1,
 		.pll_od2 = 1,
 		.pll_od3 = 2,
 		.vid_pll_div = VID_PLL_DIV_5,
 		.vclk_div = 1,
 	},
+	[MESON_VCLK_HDMI_594000_YUV420] = {
+		.pll_freq = 5940000,
+		.phy_freq = 2970000,
+		.venc_freq = 594000,
+		.vclk_freq = 594000,
+		.pixel_freq = 297000,
+		.pll_od1 = 2,
+		.pll_od2 = 1,
+		.pll_od3 = 1,
+		.vid_pll_div = VID_PLL_DIV_5,
+		.vclk_div = 1,
+	},
 	{ /* sentinel */ },
 };
 
@@ -701,6 +739,7 @@ static void meson_hdmi_pll_generic_set(struct meson_drm *priv,
 	unsigned int od, m, frac, od1, od2, od3;
 
 	if (meson_hdmi_pll_find_params(priv, pll_freq, &m, &frac, &od)) {
+		/* OD2 goes to the PHY, and needs to be *10, so keep OD3=1 */
 		od3 = 1;
 		if (od < 4) {
 			od1 = 2;
@@ -723,21 +762,28 @@ static void meson_hdmi_pll_generic_set(struct meson_drm *priv,
 }
 
 enum drm_mode_status
-meson_vclk_vic_supported_freq(unsigned int freq)
+meson_vclk_vic_supported_freq(unsigned int phy_freq,
+			      unsigned int vclk_freq)
 {
 	int i;
 
-	DRM_DEBUG_DRIVER("freq = %d\n", freq);
+	DRM_DEBUG_DRIVER("phy_freq = %d vclk_freq = %d\n",
+			 phy_freq, vclk_freq);
 
 	for (i = 0 ; params[i].pixel_freq ; ++i) {
 		DRM_DEBUG_DRIVER("i = %d pixel_freq = %d alt = %d\n",
 				 i, params[i].pixel_freq,
 				 FREQ_1000_1001(params[i].pixel_freq));
+		DRM_DEBUG_DRIVER("i = %d phy_freq = %d alt = %d\n",
+				 i, params[i].phy_freq,
+				 FREQ_1000_1001(params[i].phy_freq/10)*10);
 		/* Match strict frequency */
-		if (freq == params[i].pixel_freq)
+		if (phy_freq == params[i].phy_freq &&
+		    vclk_freq == params[i].vclk_freq)
 			return MODE_OK;
 		/* Match 1000/1001 variant */
-		if (freq == FREQ_1000_1001(params[i].pixel_freq))
+		if (phy_freq == (FREQ_1000_1001(params[i].phy_freq/10)*10) &&
+		    vclk_freq == FREQ_1000_1001(params[i].vclk_freq))
 			return MODE_OK;
 	}
 
@@ -965,8 +1011,9 @@ static void meson_vclk_set(struct meson_drm *priv, unsigned int pll_base_freq,
 }
 
 void meson_vclk_setup(struct meson_drm *priv, unsigned int target,
-		      unsigned int vclk_freq, unsigned int venc_freq,
-		      unsigned int dac_freq, bool hdmi_use_enci)
+		      unsigned int phy_freq, unsigned int vclk_freq,
+		      unsigned int venc_freq, unsigned int dac_freq,
+		      bool hdmi_use_enci)
 {
 	bool vic_alternate_clock = false;
 	unsigned int freq;
@@ -986,7 +1033,7 @@ void meson_vclk_setup(struct meson_drm *priv, unsigned int target,
 		 * - venc_div = 1
 		 * - encp encoder
 		 */
-		meson_vclk_set(priv, vclk_freq * 10, 0, 0, 0,
+		meson_vclk_set(priv, phy_freq, 0, 0, 0,
 			       VID_PLL_DIV_5, 2, 1, 1, false, false);
 		return;
 	}
@@ -1008,9 +1055,11 @@ void meson_vclk_setup(struct meson_drm *priv, unsigned int target,
 	}
 
 	for (freq = 0 ; params[freq].pixel_freq ; ++freq) {
-		if (vclk_freq == params[freq].pixel_freq ||
-		    vclk_freq == FREQ_1000_1001(params[freq].pixel_freq)) {
-			if (vclk_freq != params[freq].pixel_freq)
+		if ((phy_freq == params[freq].phy_freq ||
+		     phy_freq == FREQ_1000_1001(params[freq].phy_freq/10)*10) &&
+		    (vclk_freq == params[freq].vclk_freq ||
+		     vclk_freq == FREQ_1000_1001(params[freq].vclk_freq))) {
+			if (vclk_freq != params[freq].vclk_freq)
 				vic_alternate_clock = true;
 			else
 				vic_alternate_clock = false;
@@ -1039,7 +1088,7 @@ void meson_vclk_setup(struct meson_drm *priv, unsigned int target,
 		return;
 	}
 
-	meson_vclk_set(priv, params[freq].pll_base_freq,
+	meson_vclk_set(priv, params[freq].pll_freq,
 		       params[freq].pll_od1, params[freq].pll_od2,
 		       params[freq].pll_od3, params[freq].vid_pll_div,
 		       params[freq].vclk_div, hdmi_tx_div, venc_div,