[PATCH v3 3/4] media: rcar-csi2: Update start procedure for V4H

["Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>]

Prepare for adding D-PHY support to the driver by first updating the
generic startup procedure that covers both C-PHY and D-PHY operations.
The starting procedure where updated in later versions of the datasheet.

Most of the configuration is only documented as tables of magic values
in the documentation. Each step is however marked with a T<n> marker,
inject these markers in the comments to make it easier to map driver to
documentation.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
 drivers/media/platform/renesas/rcar-csi2.c | 84 +++++++++++++++-------
 1 file changed, 58 insertions(+), 26 deletions(-)

diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
index cdd358b4a973..7ba637d8683b 100644
--- a/drivers/media/platform/renesas/rcar-csi2.c
+++ b/drivers/media/platform/renesas/rcar-csi2.c
@@ -1199,7 +1199,8 @@ static int rcsi2_wait_phy_start_v4h(struct rcar_csi2 *priv, u32 match)
 	return -ETIMEDOUT;
 }
 
-static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
+static const struct rcsi2_cphy_setting *
+rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
 {
 	const struct rcsi2_cphy_setting *conf;
 	int msps;
@@ -1214,7 +1215,7 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
 
 	if (!conf->msps) {
 		dev_err(priv->dev, "Unsupported PHY speed for msps setting (%u Msps)", msps);
-		return -ERANGE;
+		return NULL;
 	}
 
 	/* C-PHY specific */
@@ -1278,27 +1279,14 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
 	/* TODO: This registers is not documented. */
 	rcsi2_write16(priv, V4H_CORE_DIG_CLANE_1_RW_HS_TX_6_REG, 0x5000);
 
-	/* Leave Shutdown mode */
-	rcsi2_write(priv, V4H_DPHY_RSTZ_REG, BIT(0));
-	rcsi2_write(priv, V4H_PHY_SHUTDOWNZ_REG, BIT(0));
-
-	/* Wait for calibration */
-	if (rcsi2_wait_phy_start_v4h(priv, V4H_ST_PHYST_ST_PHY_READY)) {
-		dev_err(priv->dev, "PHY calibration failed\n");
-		return -ETIMEDOUT;
-	}
-
-	/* C-PHY setting - analog programing*/
-	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 9), conf->lane29);
-	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 7), conf->lane27);
-
-	return 0;
+	return conf;
 }
 
 static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
 				    struct v4l2_subdev_state *state)
 {
 	const struct rcar_csi2_format *format;
+	const struct rcsi2_cphy_setting *cphy;
 	const struct v4l2_mbus_framefmt *fmt;
 	unsigned int lanes;
 	int mbps;
@@ -1318,24 +1306,35 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
 	if (mbps < 0)
 		return mbps;
 
-	/* Reset LINK and PHY*/
+	/* T0: Reset LINK and PHY*/
 	rcsi2_write(priv, V4H_CSI2_RESETN_REG, 0);
 	rcsi2_write(priv, V4H_DPHY_RSTZ_REG, 0);
 	rcsi2_write(priv, V4H_PHY_SHUTDOWNZ_REG, 0);
 
-	/* PHY static setting */
-	rcsi2_write(priv, V4H_PHY_EN_REG, V4H_PHY_EN_ENABLE_CLK);
+	/* T1: PHY static setting */
+	rcsi2_write(priv, V4H_PHY_EN_REG, V4H_PHY_EN_ENABLE_CLK |
+		    V4H_PHY_EN_ENABLE_0 | V4H_PHY_EN_ENABLE_1 |
+		    V4H_PHY_EN_ENABLE_2 | V4H_PHY_EN_ENABLE_3);
 	rcsi2_write(priv, V4H_FLDC_REG, 0);
 	rcsi2_write(priv, V4H_FLDD_REG, 0);
 	rcsi2_write(priv, V4H_IDIC_REG, 0);
 	rcsi2_write(priv, V4H_PHY_MODE_REG, V4H_PHY_MODE_CPHY);
 	rcsi2_write(priv, V4H_N_LANES_REG, lanes - 1);
 
-	/* Reset CSI2 */
+	rcsi2_write(priv, V4M_FRXM_REG,
+		    V4M_FRXM_FORCERXMODE_0 | V4M_FRXM_FORCERXMODE_1 |
+		    V4M_FRXM_FORCERXMODE_2 | V4M_FRXM_FORCERXMODE_3);
+	rcsi2_write(priv, V4M_OVR1_REG,
+		    V4M_OVR1_FORCERXMODE_0 | V4M_OVR1_FORCERXMODE_1 |
+		    V4M_OVR1_FORCERXMODE_2 | V4M_OVR1_FORCERXMODE_3);
+
+	/* T2: Reset CSI2 */
 	rcsi2_write(priv, V4H_CSI2_RESETN_REG, BIT(0));
 
 	/* Registers static setting through APB */
 	/* Common setting */
+	rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(10), 0x0030);
+	rcsi2_write16(priv, V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(2), 0x1444);
 	rcsi2_write16(priv, V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(0), 0x1bfd);
 	rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_STARTUP_1_1_REG, 0x0233);
 	rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(6), 0x0027);
@@ -1350,15 +1349,48 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
 	rcsi2_write16(priv, V4H_PPI_RW_LPDCOCAL_COARSE_CFG_REG, 0x0105);
 	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(6), 0x1000);
 	rcsi2_write16(priv, V4H_PPI_RW_COMMON_CFG_REG, 0x0003);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(0), 0x0000);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(1), 0x0400);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(3), 0x41f6);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(0), 0x0000);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(3), 0x43f6);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(6), 0x3000);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(7), 0x0000);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(6), 0x7000);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(7), 0x0000);
+	rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(5), 0x4000);
 
-	/* C-PHY settings */
-	ret = rcsi2_c_phy_setting_v4h(priv, mbps);
-	if (ret)
-		return ret;
+	/* T3: PHY settings */
+	cphy = rcsi2_c_phy_setting_v4h(priv, mbps);
+	if (!cphy)
+		return -ERANGE;
 
+	/* T4: Leave Shutdown mode */
+	rcsi2_write(priv, V4H_DPHY_RSTZ_REG, BIT(0));
+	rcsi2_write(priv, V4H_PHY_SHUTDOWNZ_REG, BIT(0));
+
+	/* T5: Wait for calibration */
+	if (rcsi2_wait_phy_start_v4h(priv, V4H_ST_PHYST_ST_PHY_READY)) {
+		dev_err(priv->dev, "PHY calibration failed\n");
+		return -ETIMEDOUT;
+	}
+
+	/* T6: Analog programming */
+	for (unsigned int l = 0; l < 3; l++) {
+		rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
+			      cphy->lane29);
+		rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 7),
+			      cphy->lane27);
+	}
+
+	/* T7: Wait for stop state */
 	rcsi2_wait_phy_start_v4h(priv, V4H_ST_PHYST_ST_STOPSTATE_0 |
 				 V4H_ST_PHYST_ST_STOPSTATE_1 |
-				 V4H_ST_PHYST_ST_STOPSTATE_2);
+				 V4H_ST_PHYST_ST_STOPSTATE_2 |
+				 V4H_ST_PHYST_ST_STOPSTATE_3);
+
+	/* T8: De-assert FRXM */
+	rcsi2_write(priv, V4M_FRXM_REG, 0);
 
 	return 0;
 }
-- 
2.49.0