drm: rcar-du: lvds: Add R-Car Gen3 support

The LVDS encoder differs slightly in Gen3 SoCs in its PLL configuration.
Add support for the Gen3 LVDS PLL parameters and startup procedure.
Signed-off-by: Koji Matsuoka <koji.matsuoka.xm@renesas.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

drivers/gpu/drm/rcar-du/Kconfig

@@ -21,10 +21,8 @@ config DRM_RCAR_HDMI
 config DRM_RCAR_LVDS
 	bool "R-Car DU LVDS Encoder Support"
 	depends on DRM_RCAR_DU
-	depends on ARCH_R8A7790 || ARCH_R8A7791 || COMPILE_TEST
 	help
-	  Enable support for the R-Car Display Unit embedded LVDS encoders
-	  (currently only on R8A7790 and R8A7791).
+	  Enable support for the R-Car Display Unit embedded LVDS encoders.
 
 config DRM_RCAR_VSP
 	bool "R-Car DU VSP Compositor Support"

drivers/gpu/drm/rcar-du/rcar_du_drv.c

@@ -140,15 +140,21 @@ static const struct rcar_du_device_info rcar_du_r8a7795_info = {
 		  | RCAR_DU_FEATURE_VSP1_SOURCE,
 	.num_crtcs = 4,
 	.routes = {
-		/* R8A7795 has one RGB output, and two HDMI and one LVDS
-		 * (currently unsupported) outputs
+		/* R8A7795 has one RGB output, one LVDS output and two
+		 * (currently unsupported) HDMI outputs.
 		 */
 		[RCAR_DU_OUTPUT_DPAD0] = {
 			.possible_crtcs = BIT(3),
 			.encoder_type = DRM_MODE_ENCODER_NONE,
 			.port = 0,
 		},
+		[RCAR_DU_OUTPUT_LVDS0] = {
+			.possible_crtcs = BIT(0),
+			.encoder_type = DRM_MODE_ENCODER_LVDS,
+			.port = 3,
+		},
 	},
+	.num_lvds = 1,
 };
 
 static const struct of_device_id rcar_du_of_table[] = {

drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c

@@ -38,22 +38,13 @@ static void rcar_lvds_write(struct rcar_du_lvdsenc *lvds, u32 reg, u32 data)
 	iowrite32(data, lvds->mmio + reg);
 }
 
-static int rcar_du_lvdsenc_start(struct rcar_du_lvdsenc *lvds,
-				 struct rcar_du_crtc *rcrtc)
+static void rcar_du_lvdsenc_start_gen2(struct rcar_du_lvdsenc *lvds,
+				       struct rcar_du_crtc *rcrtc)
 {
 	const struct drm_display_mode *mode = &rcrtc->crtc.mode;
 	unsigned int freq = mode->clock;
 	u32 lvdcr0;
-	u32 lvdhcr;
 	u32 pllcr;
-	int ret;
-
-	if (lvds->enabled)
-		return 0;
-
-	ret = clk_prepare_enable(lvds->clock);
-	if (ret < 0)
-		return ret;
 
 	/* PLL clock configuration */
 	if (freq < 39000)
@@ -67,26 +58,6 @@ static int rcar_du_lvdsenc_start(struct rcar_du_lvdsenc *lvds,
 
 	rcar_lvds_write(lvds, LVDPLLCR, pllcr);
 
-	/* Hardcode the channels and control signals routing for now.
-	 *
-	 * HSYNC -> CTRL0
-	 * VSYNC -> CTRL1
-	 * DISP  -> CTRL2
-	 * 0     -> CTRL3
-	 */
-	rcar_lvds_write(lvds, LVDCTRCR, LVDCTRCR_CTR3SEL_ZERO |
-			LVDCTRCR_CTR2SEL_DISP | LVDCTRCR_CTR1SEL_VSYNC |
-			LVDCTRCR_CTR0SEL_HSYNC);
-
-	if (rcar_du_needs(lvds->dev, RCAR_DU_QUIRK_LVDS_LANES))
-		lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 3)
-		       | LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 1);
-	else
-		lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 1)
-		       | LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 3);
-
-	rcar_lvds_write(lvds, LVDCHCR, lvdhcr);
-
 	/* Select the input, hardcode mode 0, enable LVDS operation and turn
 	 * bias circuitry on.
 	 */
@@ -96,8 +67,10 @@ static int rcar_du_lvdsenc_start(struct rcar_du_lvdsenc *lvds,
 	rcar_lvds_write(lvds, LVDCR0, lvdcr0);
 
 	/* Turn all the channels on. */
-	rcar_lvds_write(lvds, LVDCR1, LVDCR1_CHSTBY(3) | LVDCR1_CHSTBY(2) |
-			LVDCR1_CHSTBY(1) | LVDCR1_CHSTBY(0) | LVDCR1_CLKSTBY);
+	rcar_lvds_write(lvds, LVDCR1,
+			LVDCR1_CHSTBY_GEN2(3) | LVDCR1_CHSTBY_GEN2(2) |
+			LVDCR1_CHSTBY_GEN2(1) | LVDCR1_CHSTBY_GEN2(0) |
+			LVDCR1_CLKSTBY_GEN2);
 
 	/* Turn the PLL on, wait for the startup delay, and turn the output
 	 * on.
@@ -109,8 +82,90 @@ static int rcar_du_lvdsenc_start(struct rcar_du_lvdsenc *lvds,
 
 	lvdcr0 |= LVDCR0_LVRES;
 	rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+}
+
+static void rcar_du_lvdsenc_start_gen3(struct rcar_du_lvdsenc *lvds,
+				       struct rcar_du_crtc *rcrtc)
+{
+	const struct drm_display_mode *mode = &rcrtc->crtc.mode;
+	unsigned int freq = mode->clock;
+	u32 lvdcr0;
+	u32 pllcr;
+
+	/* PLL clock configuration */
+	if (freq < 42000)
+		pllcr = LVDPLLCR_PLLDIVCNT_42M;
+	else if (freq < 85000)
+		pllcr = LVDPLLCR_PLLDIVCNT_85M;
+	else if (freq < 128000)
+		pllcr = LVDPLLCR_PLLDIVCNT_128M;
+	else
+		pllcr = LVDPLLCR_PLLDIVCNT_148M;
+
+	rcar_lvds_write(lvds, LVDPLLCR, pllcr);
+
+	/* Turn the PLL on, set it to LVDS normal mode, wait for the startup
+	 * delay and turn the output on.
+	 */
+	lvdcr0 = LVDCR0_PLLON;
+	rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+
+	lvdcr0 |= LVDCR0_PWD;
+	rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+
+	usleep_range(100, 150);
+
+	lvdcr0 |= LVDCR0_LVRES;
+	rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+
+	/* Turn all the channels on. */
+	rcar_lvds_write(lvds, LVDCR1,
+			LVDCR1_CHSTBY_GEN3(3) | LVDCR1_CHSTBY_GEN3(2) |
+			LVDCR1_CHSTBY_GEN3(1) | LVDCR1_CHSTBY_GEN3(0) |
+			LVDCR1_CLKSTBY_GEN3);
+}
+
+static int rcar_du_lvdsenc_start(struct rcar_du_lvdsenc *lvds,
+				 struct rcar_du_crtc *rcrtc)
+{
+	u32 lvdhcr;
+	int ret;
+
+	if (lvds->enabled)
+		return 0;
+
+	ret = clk_prepare_enable(lvds->clock);
+	if (ret < 0)
+		return ret;
+
+	/* Hardcode the channels and control signals routing for now.
+	 *
+	 * HSYNC -> CTRL0
+	 * VSYNC -> CTRL1
+	 * DISP  -> CTRL2
+	 * 0     -> CTRL3
+	 */
+	rcar_lvds_write(lvds, LVDCTRCR, LVDCTRCR_CTR3SEL_ZERO |
+			LVDCTRCR_CTR2SEL_DISP | LVDCTRCR_CTR1SEL_VSYNC |
+			LVDCTRCR_CTR0SEL_HSYNC);
+
+	if (rcar_du_needs(lvds->dev, RCAR_DU_QUIRK_LVDS_LANES))
+		lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 3)
+		       | LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 1);
+	else
+		lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 1)
+		       | LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 3);
+
+	rcar_lvds_write(lvds, LVDCHCR, lvdhcr);
+
+	/* Perform generation-specific initialization. */
+	if (lvds->dev->info->gen < 3)
+		rcar_du_lvdsenc_start_gen2(lvds, rcrtc);
+	else
+		rcar_du_lvdsenc_start_gen3(lvds, rcrtc);
 
 	lvds->enabled = true;
+
 	return 0;
 }
 
@@ -143,10 +198,16 @@ int rcar_du_lvdsenc_enable(struct rcar_du_lvdsenc *lvds, struct drm_crtc *crtc,
 void rcar_du_lvdsenc_atomic_check(struct rcar_du_lvdsenc *lvds,
 				  struct drm_display_mode *mode)
 {
-	/* The internal LVDS encoder has a clock frequency operating range of
-	 * 30MHz to 150MHz. Clamp the clock accordingly.
+	struct rcar_du_device *rcdu = lvds->dev;
+
+	/* The internal LVDS encoder has a restricted clock frequency operating
+	 * range (30MHz to 150MHz on Gen2, 25.175MHz to 148.5MHz on Gen3). Clamp
+	 * the clock accordingly.
 	 */
-	mode->clock = clamp(mode->clock, 30000, 150000);
+	if (rcdu->info->gen < 3)
+		mode->clock = clamp(mode->clock, 30000, 150000);
+	else
+		mode->clock = clamp(mode->clock, 25175, 148500);
 }
 
 static int rcar_du_lvdsenc_get_resources(struct rcar_du_lvdsenc *lvds,

drivers/gpu/drm/rcar-du/rcar_lvds_regs.h

 /*
  * rcar_lvds_regs.h  --  R-Car LVDS Interface Registers Definitions
  *
- * Copyright (C) 2013 Renesas Electronics Corporation
+ * Copyright (C) 2013-2015 Renesas Electronics Corporation
  *
  * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
  *
@@ -15,28 +15,38 @@
 
 #define LVDCR0				0x0000
 #define LVDCR0_DUSEL			(1 << 15)
-#define LVDCR0_DMD			(1 << 12)
+#define LVDCR0_DMD			(1 << 12)		/* Gen2 only */
 #define LVDCR0_LVMD_MASK		(0xf << 8)
 #define LVDCR0_LVMD_SHIFT		8
 #define LVDCR0_PLLON			(1 << 4)
-#define LVDCR0_BEN			(1 << 2)
-#define LVDCR0_LVEN			(1 << 1)
+#define LVDCR0_PWD			(1 << 2)		/* Gen3 only */
+#define LVDCR0_BEN			(1 << 2)		/* Gen2 only */
+#define LVDCR0_LVEN			(1 << 1)		/* Gen2 only */
 #define LVDCR0_LVRES			(1 << 0)
 
 #define LVDCR1				0x0004
-#define LVDCR1_CKSEL			(1 << 15)
-#define LVDCR1_CHSTBY(n)		(3 << (2 + (n) * 2))
-#define LVDCR1_CLKSTBY			(3 << 0)
+#define LVDCR1_CKSEL			(1 << 15)		/* Gen2 only */
+#define LVDCR1_CHSTBY_GEN2(n)		(3 << (2 + (n) * 2))	/* Gen2 only */
+#define LVDCR1_CHSTBY_GEN3(n)		(1 << (2 + (n) * 2))	/* Gen3 only */
+#define LVDCR1_CLKSTBY_GEN2		(3 << 0)		/* Gen2 only */
+#define LVDCR1_CLKSTBY_GEN3		(1 << 0)		/* Gen3 only */
 
 #define LVDPLLCR			0x0008
 #define LVDPLLCR_CEEN			(1 << 14)
 #define LVDPLLCR_FBEN			(1 << 13)
 #define LVDPLLCR_COSEL			(1 << 12)
+/* Gen2 */
 #define LVDPLLCR_PLLDLYCNT_150M		(0x1bf << 0)
 #define LVDPLLCR_PLLDLYCNT_121M		(0x22c << 0)
 #define LVDPLLCR_PLLDLYCNT_60M		(0x77b << 0)
 #define LVDPLLCR_PLLDLYCNT_38M		(0x69a << 0)
 #define LVDPLLCR_PLLDLYCNT_MASK		(0x7ff << 0)
+/* Gen3 */
+#define LVDPLLCR_PLLDIVCNT_42M		(0x014cb << 0)
+#define LVDPLLCR_PLLDIVCNT_85M		(0x00a45 << 0)
+#define LVDPLLCR_PLLDIVCNT_128M		(0x006c3 << 0)
+#define LVDPLLCR_PLLDIVCNT_148M		(0x046c1 << 0)
+#define LVDPLLCR_PLLDIVCNT_MASK		(0x7ffff << 0)
 
 #define LVDCTRCR			0x000c
 #define LVDCTRCR_CTR3SEL_ZERO		(0 << 12)