video: tegra20: add MIPI calibration driver

Dedicated MIPI calibration driver is used on T114 and newer. Before
T114 MIPI calibration registers were part of VI and CSI.

Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # Nvidia Tegratab T114
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>

drivers/video/tegra20/Makefile

@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0+
 
 obj-$(CONFIG_VIDEO_TEGRA20) += tegra-dc.o
-obj-$(CONFIG_VIDEO_DSI_TEGRA30) += tegra-dsi.o mipi-phy.o
+obj-$(CONFIG_VIDEO_DSI_TEGRA30) += tegra-dsi.o tegra-mipi.o mipi-phy.o
 obj-$(CONFIG_TEGRA_BACKLIGHT_PWM) += tegra-pwm-backlight.o

drivers/video/tegra20/tegra-mipi.c

@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2013 NVIDIA Corporation
+ * Copyright (c) 2023 Svyatoslav Ryhel <clamor95@gmail.com>
+ */
+
+#include <dm.h>
+#include <clk.h>
+#include <misc.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+
+#include <asm/io.h>
+
+/* MIPI control registers 0x00 ~ 0x60 */
+struct mipi_ctlr {
+	uint mipi_cal_ctrl;
+	uint mipi_cal_autocal_ctrl;
+	uint mipi_cal_status;
+
+	uint unused1[2];
+
+	uint mipi_cal_config_csia;
+	uint mipi_cal_config_csib;
+	uint mipi_cal_config_csic;
+	uint mipi_cal_config_csid;
+	uint mipi_cal_config_csie;
+
+	uint unused2[4];
+
+	uint mipi_cal_config_dsia;
+	uint mipi_cal_config_dsib;
+	uint mipi_cal_config_dsic;
+	uint mipi_cal_config_dsid;
+
+	uint unused3[4];
+
+	uint mipi_cal_bias_pad_cfg0;
+	uint mipi_cal_bias_pad_cfg1;
+	uint mipi_cal_bias_pad_cfg2;
+};
+
+#define MIPI_CAL_CTRL_NOISE_FILTER(x)	(((x) & 0xf) << 26)
+#define MIPI_CAL_CTRL_PRESCALE(x)	(((x) & 0x3) << 24)
+#define MIPI_CAL_CTRL_CLKEN_OVR		BIT(4)
+#define MIPI_CAL_CTRL_START		BIT(0)
+
+#define MIPI_CAL_STATUS_DONE		BIT(16)
+#define MIPI_CAL_STATUS_ACTIVE		BIT(0)
+
+#define MIPI_CAL_OVERIDE(x)		(((x) & 0x1) << 30)
+#define MIPI_CAL_SEL(x)			(((x) & 0x1) << 21)
+#define MIPI_CAL_HSPDOS(x)		(((x) & 0x1f) << 16)
+#define MIPI_CAL_HSPUOS(x)		(((x) & 0x1f) << 8)
+#define MIPI_CAL_TERMOS(x)		(((x) & 0x1f) << 0)
+
+#define MIPI_CAL_BIAS_PAD_PDVCLAMP	BIT(1)
+#define MIPI_CAL_BIAS_PAD_E_VCLAMP_REF	BIT(0)
+
+#define MIPI_CAL_BIAS_PAD_DRV_DN_REF(x) (((x) & 0x7) << 16)
+#define MIPI_CAL_BIAS_PAD_DRV_UP_REF(x) (((x) & 0x7) << 8)
+
+#define MIPI_CAL_BIAS_PAD_VCLAMP(x)	(((x) & 0x7) << 16)
+#define MIPI_CAL_BIAS_PAD_VAUXP(x)	(((x) & 0x7) << 4)
+#define MIPI_CAL_BIAS_PAD_PDVREG	BIT(1)
+
+struct tegra_mipi_priv {
+	struct mipi_ctlr	*mipi;
+	struct clk		*mipi_cal;
+};
+
+static int tegra_mipi_calibrate(struct udevice *dev, int offset, const void *buf,
+				int size)
+{
+	struct tegra_mipi_priv *priv = dev_get_priv(dev);
+	u32 value;
+
+	value = MIPI_CAL_BIAS_PAD_DRV_DN_REF(0x2) |
+		MIPI_CAL_BIAS_PAD_DRV_UP_REF(0x0);
+	writel(value, &priv->mipi->mipi_cal_bias_pad_cfg1);
+
+	value = readl(&priv->mipi->mipi_cal_bias_pad_cfg2);
+	value &= ~MIPI_CAL_BIAS_PAD_VCLAMP(0x7);
+	value &= ~MIPI_CAL_BIAS_PAD_VAUXP(0x7);
+	writel(value, &priv->mipi->mipi_cal_bias_pad_cfg2);
+
+	value = MIPI_CAL_OVERIDE(0x0) | MIPI_CAL_SEL(0x1) |
+		MIPI_CAL_HSPDOS(0x0) | MIPI_CAL_HSPUOS(0x4) |
+		MIPI_CAL_TERMOS(0x5);
+	writel(value, &priv->mipi->mipi_cal_config_dsia);
+	writel(value, &priv->mipi->mipi_cal_config_dsib);
+
+	/* Deselect PAD C */
+	value = readl(&priv->mipi->mipi_cal_config_dsic);
+	value &= ~(MIPI_CAL_SEL(0x1));
+	writel(value, &priv->mipi->mipi_cal_config_dsic);
+
+	/* Deselect PAD D */
+	value = readl(&priv->mipi->mipi_cal_config_dsid);
+	value &= ~(MIPI_CAL_SEL(0x1));
+	writel(value, &priv->mipi->mipi_cal_config_dsid);
+
+	value = readl(&priv->mipi->mipi_cal_ctrl);
+	value &= ~MIPI_CAL_CTRL_NOISE_FILTER(0xf);
+	value &= ~MIPI_CAL_CTRL_PRESCALE(0x3);
+	value |= MIPI_CAL_CTRL_NOISE_FILTER(0xa) |
+		 MIPI_CAL_CTRL_PRESCALE(0x2) |
+		 MIPI_CAL_CTRL_CLKEN_OVR;
+	writel(value, &priv->mipi->mipi_cal_ctrl);
+
+	/* clear any pending status bits */
+	value = readl(&priv->mipi->mipi_cal_status);
+	writel(value, &priv->mipi->mipi_cal_status);
+
+	value = readl(&priv->mipi->mipi_cal_ctrl);
+	value |= MIPI_CAL_CTRL_START;
+	writel(value, &priv->mipi->mipi_cal_ctrl);
+
+	/*
+	 * Wait for min 72uS to let calibration logic finish calibration
+	 * sequence codes before waiting for pads idle state to apply the
+	 * results.
+	 */
+	udelay(80);
+
+	return readl_poll_sleep_timeout(&priv->mipi->mipi_cal_status, value,
+					!(value & MIPI_CAL_STATUS_ACTIVE) &&
+					(value & MIPI_CAL_STATUS_DONE), 100,
+					250000);
+}
+
+static int tegra_mipi_enable(struct udevice *dev, bool val)
+{
+	struct tegra_mipi_priv *priv = dev_get_priv(dev);
+	u32 value;
+
+	clk_enable(priv->mipi_cal);
+
+	value = readl(&priv->mipi->mipi_cal_bias_pad_cfg0);
+	value &= ~MIPI_CAL_BIAS_PAD_PDVCLAMP;
+	value |= MIPI_CAL_BIAS_PAD_E_VCLAMP_REF;
+	writel(value, &priv->mipi->mipi_cal_bias_pad_cfg0);
+
+	value = readl(&priv->mipi->mipi_cal_bias_pad_cfg2);
+	value &= ~MIPI_CAL_BIAS_PAD_PDVREG;
+	writel(value, &priv->mipi->mipi_cal_bias_pad_cfg2);
+
+	return 0;
+}
+
+static const struct misc_ops tegra_mipi_ops = {
+	.write = tegra_mipi_calibrate,
+	.set_enabled = tegra_mipi_enable,
+};
+
+static int tegra_mipi_probe(struct udevice *dev)
+{
+	struct tegra_mipi_priv *priv = dev_get_priv(dev);
+
+	priv->mipi = (struct mipi_ctlr *)dev_read_addr_ptr(dev);
+	if (!priv->mipi) {
+		log_debug("%s: no MIPI controller address\n", __func__);
+		return -EINVAL;
+	}
+
+	priv->mipi_cal = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->mipi_cal)) {
+		log_debug("%s: Could not get MIPI clock: %ld\n",
+			  __func__, PTR_ERR(priv->mipi_cal));
+		return PTR_ERR(priv->mipi_cal);
+	}
+
+	return 0;
+}
+
+static const struct udevice_id tegra_mipi_ids[] = {
+	{ .compatible = "nvidia,tegra114-mipi" },
+	{ }
+};
+
+U_BOOT_DRIVER(tegra_mipi) = {
+	.name           = "tegra_mipi",
+	.id             = UCLASS_MISC,
+	.ops		= &tegra_mipi_ops,
+	.of_match       = tegra_mipi_ids,
+	.probe          = tegra_mipi_probe,
+	.priv_auto	= sizeof(struct tegra_mipi_priv),
+};