phy: amlogic: Add AXG MIPI D-PHY driver

The Amlogic AXG SoCs embeds a MIPI D-PHY used to communicate with DSI
panels.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20201116101315.71720-3-narmstrong@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

3 files changed, 426 insertions, 0 deletions

diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
index 617cf073e9aa..99e8a4c7f1f3 100644
--- a/drivers/phy/amlogic/Kconfig
+++ b/drivers/phy/amlogic/Kconfig
@@ -70,3 +70,15 @@ config PHY_MESON_AXG_MIPI_PCIE_ANALOG
 	  Enable this to support the Meson MIPI + PCIE analog PHY
 	  found in Meson AXG SoCs.
 	  If unsure, say N.
+
+config PHY_MESON_AXG_MIPI_DPHY
+	tristate "Meson AXG MIPI DPHY driver"
+	default ARCH_MESON
+	depends on OF && (ARCH_MESON || COMPILE_TEST)
+	select GENERIC_PHY
+	select REGMAP_MMIO
+	select GENERIC_PHY_MIPI_DPHY
+	help
+	  Enable this to support the Meson MIPI DPHY found in Meson AXG
+	  SoCs.
+	  If unsure, say N.
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index 99702a45e9be..8fa07fbd0d92 100644
--- a/drivers/phy/amlogic/Makefile
+++ b/drivers/phy/amlogic/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_PHY_MESON_G12A_USB2)		+= phy-meson-g12a-usb2.o
 obj-$(CONFIG_PHY_MESON_G12A_USB3_PCIE)		+= phy-meson-g12a-usb3-pcie.o
 obj-$(CONFIG_PHY_MESON_AXG_PCIE)		+= phy-meson-axg-pcie.o
 obj-$(CONFIG_PHY_MESON_AXG_MIPI_PCIE_ANALOG)	+= phy-meson-axg-mipi-pcie-analog.o
+obj-$(CONFIG_PHY_MESON_AXG_MIPI_DPHY)		+= phy-meson-axg-mipi-dphy.o
diff --git a/drivers/phy/amlogic/phy-meson-axg-mipi-dphy.c b/drivers/phy/amlogic/phy-meson-axg-mipi-dphy.c
new file mode 100644
index 000000000000..cd2332bf0e31
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson-axg-mipi-dphy.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Meson AXG MIPI DPHY driver
+ *
+ * Copyright (C) 2018 Amlogic, Inc. All rights reserved
+ * Copyright (C) 2020 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+
+/* [31] soft reset for the phy.
+ *		1: reset. 0: dessert the reset.
+ * [30] clock lane soft reset.
+ * [29] data byte lane 3 soft reset.
+ * [28] data byte lane 2 soft reset.
+ * [27] data byte lane 1 soft reset.
+ * [26] data byte lane 0 soft reset.
+ * [25] mipi dsi pll clock selection.
+ *		1:  clock from fixed 850Mhz clock source. 0: from VID2 PLL.
+ * [12] mipi HSbyteclk enable.
+ * [11] mipi divider clk selection.
+ *		1: select the mipi DDRCLKHS from clock divider.
+ *		0: from PLL clock.
+ * [10] mipi clock divider control.
+ *		1: /4. 0: /2.
+ * [9]  mipi divider output enable.
+ * [8]  mipi divider counter enable.
+ * [7]  PLL clock enable.
+ * [5]  LPDT data endian.
+ *		1 = transfer the high bit first. 0 : transfer the low bit first.
+ * [4]  HS data endian.
+ * [3]  force data byte lane in stop mode.
+ * [2]  force data byte lane 0 in receiver mode.
+ * [1]  write 1 to sync the txclkesc input. the internal logic have to
+ *	use txclkesc to decide Txvalid and Txready.
+ * [0]  enalbe the MIPI DPHY TxDDRClk.
+ */
+#define MIPI_DSI_PHY_CTRL				0x0
+
+/* [31] clk lane tx_hs_en control selection.
+ *		1: from register. 0: use clk lane state machine.
+ * [30] register bit for clock lane tx_hs_en.
+ * [29] clk lane tx_lp_en contrl selection.
+ *		1: from register. 0: from clk lane state machine.
+ * [28] register bit for clock lane tx_lp_en.
+ * [27] chan0 tx_hs_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [26] register bit for chan0 tx_hs_en.
+ * [25] chan0 tx_lp_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [24] register bit from chan0 tx_lp_en.
+ * [23] chan0 rx_lp_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [22] register bit from chan0 rx_lp_en.
+ * [21] chan0 contention detection enable control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [20] register bit from chan0 contention dectection enable.
+ * [19] chan1 tx_hs_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [18] register bit for chan1 tx_hs_en.
+ * [17] chan1 tx_lp_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [16] register bit from chan1 tx_lp_en.
+ * [15] chan2 tx_hs_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [14] register bit for chan2 tx_hs_en.
+ * [13] chan2 tx_lp_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [12] register bit from chan2 tx_lp_en.
+ * [11] chan3 tx_hs_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [10] register bit for chan3 tx_hs_en.
+ * [9]  chan3 tx_lp_en control selection.
+ *		1: from register. 0: from chan0 state machine.
+ * [8]  register bit from chan3 tx_lp_en.
+ * [4]  clk chan power down. this bit is also used as the power down
+ *	of the whole MIPI_DSI_PHY.
+ * [3]  chan3 power down.
+ * [2]  chan2 power down.
+ * [1]  chan1 power down.
+ * [0]  chan0 power down.
+ */
+#define MIPI_DSI_CHAN_CTRL				0x4
+
+/* [24]   rx turn watch dog triggered.
+ * [23]   rx esc watchdog  triggered.
+ * [22]   mbias ready.
+ * [21]   txclkesc  synced and ready.
+ * [20:17] clk lane state. {mbias_ready, tx_stop, tx_ulps, tx_hs_active}
+ * [16:13] chan3 state{0, tx_stop, tx_ulps, tx_hs_active}
+ * [12:9]  chan2 state.{0, tx_stop, tx_ulps, tx_hs_active}
+ * [8:5]   chan1 state. {0, tx_stop, tx_ulps, tx_hs_active}
+ * [4:0]   chan0 state. {TX_STOP, tx_ULPS, hs_active, direction, rxulpsesc}
+ */
+#define MIPI_DSI_CHAN_STS				0x8
+
+/* [31:24] TCLK_PREPARE.
+ * [23:16] TCLK_ZERO.
+ * [15:8]  TCLK_POST.
+ * [7:0]   TCLK_TRAIL.
+ */
+#define MIPI_DSI_CLK_TIM				0xc
+
+/* [31:24] THS_PREPARE.
+ * [23:16] THS_ZERO.
+ * [15:8]  THS_TRAIL.
+ * [7:0]   THS_EXIT.
+ */
+#define MIPI_DSI_HS_TIM					0x10
+
+/* [31:24] tTA_GET.
+ * [23:16] tTA_GO.
+ * [15:8]  tTA_SURE.
+ * [7:0]   tLPX.
+ */
+#define MIPI_DSI_LP_TIM					0x14
+
+/* wait time to  MIPI DIS analog ready. */
+#define MIPI_DSI_ANA_UP_TIM				0x18
+
+/* TINIT. */
+#define MIPI_DSI_INIT_TIM				0x1c
+
+/* TWAKEUP. */
+#define MIPI_DSI_WAKEUP_TIM				0x20
+
+/* when in RxULPS check state, after the the logic enable the analog,
+ *	how long we should wait to check the lP state .
+ */
+#define MIPI_DSI_LPOK_TIM				0x24
+
+/* Watchdog for RX low power state no finished. */
+#define MIPI_DSI_LP_WCHDOG				0x28
+
+/* tMBIAS,  after send power up signals to analog,
+ *	how long we should wait for analog powered up.
+ */
+#define MIPI_DSI_ANA_CTRL				0x2c
+
+/* [31:8]  reserved for future.
+ * [7:0]   tCLK_PRE.
+ */
+#define MIPI_DSI_CLK_TIM1				0x30
+
+/* watchdog for turn around waiting time. */
+#define MIPI_DSI_TURN_WCHDOG				0x34
+
+/* When in RxULPS state, how frequency we should to check
+ *	if the TX side out of ULPS state.
+ */
+#define MIPI_DSI_ULPS_CHECK				0x38
+#define MIPI_DSI_TEST_CTRL0				0x3c
+#define MIPI_DSI_TEST_CTRL1				0x40
+
+struct phy_meson_axg_mipi_dphy_priv {
+	struct device				*dev;
+	struct regmap				*regmap;
+	struct clk				*clk;
+	struct reset_control			*reset;
+	struct phy				*analog;
+	struct phy_configure_opts_mipi_dphy	config;
+};
+
+static const struct regmap_config phy_meson_axg_mipi_dphy_regmap_conf = {
+	.reg_bits = 8,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = MIPI_DSI_TEST_CTRL1,
+};
+
+static int phy_meson_axg_mipi_dphy_init(struct phy *phy)
+{
+	struct phy_meson_axg_mipi_dphy_priv *priv = phy_get_drvdata(phy);
+	int ret;
+
+	ret = phy_init(priv->analog);
+	if (ret)
+		return ret;
+
+	ret = reset_control_reset(priv->reset);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int phy_meson_axg_mipi_dphy_configure(struct phy *phy,
+					      union phy_configure_opts *opts)
+{
+	struct phy_meson_axg_mipi_dphy_priv *priv = phy_get_drvdata(phy);
+	int ret;
+
+	ret = phy_mipi_dphy_config_validate(&opts->mipi_dphy);
+	if (ret)
+		return ret;
+
+	ret = phy_configure(priv->analog, opts);
+	if (ret)
+		return ret;
+
+	memcpy(&priv->config, opts, sizeof(priv->config));
+
+	return 0;
+}
+
+static int phy_meson_axg_mipi_dphy_power_on(struct phy *phy)
+{
+	struct phy_meson_axg_mipi_dphy_priv *priv = phy_get_drvdata(phy);
+	int ret;
+	unsigned long temp;
+
+	ret = phy_power_on(priv->analog);
+	if (ret)
+		return ret;
+
+	/* enable phy clock */
+	regmap_write(priv->regmap, MIPI_DSI_PHY_CTRL,  0x1);
+	regmap_write(priv->regmap, MIPI_DSI_PHY_CTRL,
+		     BIT(0) | /* enable the DSI PLL clock . */
+		     BIT(7) | /* enable pll clock which connected to DDR clock path */
+		     BIT(8)); /* enable the clock divider counter */
+
+	/* enable the divider clock out */
+	regmap_update_bits(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(9), BIT(9));
+
+	/* enable the byte clock generation. */
+	regmap_update_bits(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(12), BIT(12));
+	regmap_update_bits(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(31), BIT(31));
+	regmap_update_bits(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(31), 0);
+
+	/* Calculate lanebyteclk period in ps */
+	temp = (1000000 * 100) / (priv->config.hs_clk_rate / 1000);
+	temp = temp * 8 * 10;
+
+	regmap_write(priv->regmap, MIPI_DSI_CLK_TIM,
+		     DIV_ROUND_UP(priv->config.clk_trail, temp) |
+		     (DIV_ROUND_UP(priv->config.clk_post +
+				   priv->config.hs_trail, temp) << 8) |
+		     (DIV_ROUND_UP(priv->config.clk_zero, temp) << 16) |
+		     (DIV_ROUND_UP(priv->config.clk_prepare, temp) << 24));
+	regmap_write(priv->regmap, MIPI_DSI_CLK_TIM1,
+		     DIV_ROUND_UP(priv->config.clk_pre, temp));
+
+	regmap_write(priv->regmap, MIPI_DSI_HS_TIM,
+		     DIV_ROUND_UP(priv->config.hs_exit, temp) |
+		     (DIV_ROUND_UP(priv->config.hs_trail, temp) << 8) |
+		     (DIV_ROUND_UP(priv->config.hs_zero, temp) << 16) |
+		     (DIV_ROUND_UP(priv->config.hs_prepare, temp) << 24));
+
+	regmap_write(priv->regmap, MIPI_DSI_LP_TIM,
+		     DIV_ROUND_UP(priv->config.lpx, temp) |
+		     (DIV_ROUND_UP(priv->config.ta_sure, temp) << 8) |
+		     (DIV_ROUND_UP(priv->config.ta_go, temp) << 16) |
+		     (DIV_ROUND_UP(priv->config.ta_get, temp) << 24));
+
+	regmap_write(priv->regmap, MIPI_DSI_ANA_UP_TIM, 0x0100);
+	regmap_write(priv->regmap, MIPI_DSI_INIT_TIM,
+		     DIV_ROUND_UP(priv->config.init * NSEC_PER_MSEC, temp));
+	regmap_write(priv->regmap, MIPI_DSI_WAKEUP_TIM,
+		     DIV_ROUND_UP(priv->config.wakeup * NSEC_PER_MSEC, temp));
+	regmap_write(priv->regmap, MIPI_DSI_LPOK_TIM, 0x7C);
+	regmap_write(priv->regmap, MIPI_DSI_ULPS_CHECK, 0x927C);
+	regmap_write(priv->regmap, MIPI_DSI_LP_WCHDOG, 0x1000);
+	regmap_write(priv->regmap, MIPI_DSI_TURN_WCHDOG, 0x1000);
+
+	/* Powerup the analog circuit */
+	switch (priv->config.lanes) {
+	case 1:
+		regmap_write(priv->regmap, MIPI_DSI_CHAN_CTRL, 0xe);
+		break;
+	case 2:
+		regmap_write(priv->regmap, MIPI_DSI_CHAN_CTRL, 0xc);
+		break;
+	case 3:
+		regmap_write(priv->regmap, MIPI_DSI_CHAN_CTRL, 0x8);
+		break;
+	case 4:
+	default:
+		regmap_write(priv->regmap, MIPI_DSI_CHAN_CTRL, 0);
+		break;
+	}
+
+	/* Trigger a sync active for esc_clk */
+	regmap_update_bits(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(1), BIT(1));
+
+	return 0;
+}
+
+static int phy_meson_axg_mipi_dphy_power_off(struct phy *phy)
+{
+	struct phy_meson_axg_mipi_dphy_priv *priv = phy_get_drvdata(phy);
+
+	regmap_write(priv->regmap, MIPI_DSI_CHAN_CTRL, 0xf);
+	regmap_write(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(31));
+
+	phy_power_off(priv->analog);
+
+	return 0;
+}
+
+static int phy_meson_axg_mipi_dphy_exit(struct phy *phy)
+{
+	struct phy_meson_axg_mipi_dphy_priv *priv = phy_get_drvdata(phy);
+	int ret;
+
+	ret = phy_exit(priv->analog);
+	if (ret)
+		return ret;
+
+	return reset_control_reset(priv->reset);
+}
+
+static const struct phy_ops phy_meson_axg_mipi_dphy_ops = {
+	.configure	= phy_meson_axg_mipi_dphy_configure,
+	.init		= phy_meson_axg_mipi_dphy_init,
+	.exit		= phy_meson_axg_mipi_dphy_exit,
+	.power_on	= phy_meson_axg_mipi_dphy_power_on,
+	.power_off	= phy_meson_axg_mipi_dphy_power_off,
+	.owner		= THIS_MODULE,
+};
+
+static int phy_meson_axg_mipi_dphy_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct phy_provider *phy_provider;
+	struct resource *res;
+	struct phy_meson_axg_mipi_dphy_priv *priv;
+	struct phy *phy;
+	void __iomem *base;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+	platform_set_drvdata(pdev, priv);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	priv->regmap = devm_regmap_init_mmio(dev, base,
+					&phy_meson_axg_mipi_dphy_regmap_conf);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	priv->clk = devm_clk_get(dev, "pclk");
+	if (IS_ERR(priv->clk))
+		return PTR_ERR(priv->clk);
+
+	priv->reset = devm_reset_control_get(dev, "phy");
+	if (IS_ERR(priv->reset))
+		return PTR_ERR(priv->reset);
+
+	priv->analog = devm_phy_get(dev, "analog");
+	if (IS_ERR(priv->analog))
+		return PTR_ERR(priv->analog);
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	ret = reset_control_deassert(priv->reset);
+	if (ret)
+		return ret;
+
+	phy = devm_phy_create(dev, NULL, &phy_meson_axg_mipi_dphy_ops);
+	if (IS_ERR(phy)) {
+		ret = PTR_ERR(phy);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to create PHY\n");
+
+		return ret;
+	}
+
+	phy_set_drvdata(phy, priv);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id phy_meson_axg_mipi_dphy_of_match[] = {
+	{ .compatible = "amlogic,axg-mipi-dphy", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, phy_meson_axg_mipi_dphy_of_match);
+
+static struct platform_driver phy_meson_axg_mipi_dphy_driver = {
+	.probe	= phy_meson_axg_mipi_dphy_probe,
+	.driver	= {
+		.name		= "phy-meson-axg-mipi-dphy",
+		.of_match_table	= phy_meson_axg_mipi_dphy_of_match,
+	},
+};
+module_platform_driver(phy_meson_axg_mipi_dphy_driver);
+
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_DESCRIPTION("Meson AXG MIPI DPHY driver");
+MODULE_LICENSE("GPL v2");