phy: Add Amlogic AXG MIPI D-PHY driver

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

This D-PHY depends on a separate analog PHY.

Signed-off-by:Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>

3 files changed, 403 insertions, 0 deletions

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 425737cb394..95050c188cb 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -196,6 +196,15 @@ config MESON_G12A_USB_PHY
 	  This is the generic phy driver for the Amlogic Meson G12A
 	  USB2 and USB3 PHYS.
 
+config MESON_AXG_MIPI_DPHY
+	bool "Amlogic Meson AXG MIPI D-PHY"
+	depends on PHY && ARCH_MESON && MESON_AXG
+	select MIPI_DPHY_HELPERS
+	imply REGMAP
+	help
+	  This is the generic phy driver for the Amlogic Meson AXG
+	  MIPI D-PHY.
+
 config MSM8916_USB_PHY
 	bool "Qualcomm MSM8916 USB PHY support"
 	depends on PHY
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 7b81ff77ea4..bd853e7fca9 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_PHY_STM32_USBPHYC) += phy-stm32-usbphyc.o
 obj-$(CONFIG_MESON_GXBB_USB_PHY) += meson-gxbb-usb2.o
 obj-$(CONFIG_MESON_GXL_USB_PHY) += meson-gxl-usb2.o
 obj-$(CONFIG_MESON_G12A_USB_PHY) += meson-g12a-usb2.o meson-g12a-usb3-pcie.o
+obj-$(CONFIG_MESON_AXG_MIPI_DPHY) += meson-axg-mipi-dphy.o
 obj-$(CONFIG_MSM8916_USB_PHY) += msm8916-usbh-phy.o
 obj-$(CONFIG_OMAP_USB2_PHY) += omap-usb2-phy.o
 obj-$(CONFIG_KEYSTONE_USB_PHY) += keystone-usb-phy.o
diff --git a/drivers/phy/meson-axg-mipi-dphy.c b/drivers/phy/meson-axg-mipi-dphy.c
new file mode 100644
index 00000000000..8b2469793dd
--- /dev/null
+++ b/drivers/phy/meson-axg-mipi-dphy.c
@@ -0,0 +1,393 @@
+// 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 <common.h>
+#include <log.h>
+#include <malloc.h>
+#include <asm/io.h>
+#include <bitfield.h>
+#include <dm.h>
+#include <errno.h>
+#include <generic-phy.h>
+#include <regmap.h>
+#include <linux/delay.h>
+#include <power/regulator.h>
+#include <reset.h>
+#include <clk.h>
+#include <phy-mipi-dphy.h>
+
+#include <linux/bitops.h>
+#include <linux/compat.h>
+#include <linux/bitfield.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
+
+#define NSEC_PER_MSEC	1000000L
+
+struct phy_meson_axg_mipi_dphy_priv {
+	struct regmap *regmap;
+#if CONFIG_IS_ENABLED(CLK)
+	struct clk clk;
+#endif
+	struct reset_ctl reset;
+	struct phy analog;
+	struct phy_configure_opts_mipi_dphy config;
+};
+
+static int phy_meson_axg_mipi_dphy_configure(struct phy *phy, void *params)
+{
+	struct udevice *dev = phy->dev;
+	struct phy_meson_axg_mipi_dphy_priv *priv = dev_get_priv(dev);
+	struct phy_configure_opts_mipi_dphy *config = params;
+	int ret;
+
+	ret = phy_mipi_dphy_config_validate(config);
+	if (ret)
+		return ret;
+
+	ret = generic_phy_configure(&priv->analog, config);
+	if (ret)
+		return ret;
+
+	memcpy(&priv->config, config, sizeof(priv->config));
+
+	return 0;
+}
+
+static int phy_meson_axg_mipi_dphy_power_on(struct phy *phy)
+{
+	struct udevice *dev = phy->dev;
+	struct phy_meson_axg_mipi_dphy_priv *priv = dev_get_priv(dev);
+	unsigned long temp;
+	int ret;
+
+	ret = generic_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 udevice *dev = phy->dev;
+	struct phy_meson_axg_mipi_dphy_priv *priv = dev_get_priv(dev);
+
+	regmap_write(priv->regmap, MIPI_DSI_CHAN_CTRL, 0xf);
+	regmap_write(priv->regmap, MIPI_DSI_PHY_CTRL, BIT(31));
+
+	return generic_phy_power_off(&priv->analog);
+}
+
+static int phy_meson_axg_mipi_dphy_init(struct phy *phy)
+{
+	struct udevice *dev = phy->dev;
+	struct phy_meson_axg_mipi_dphy_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = generic_phy_init(&priv->analog);
+	if (ret)
+		return ret;
+
+	ret = reset_assert(&priv->reset);
+	udelay(1);
+	ret |= reset_deassert(&priv->reset);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int phy_meson_axg_mipi_dphy_exit(struct phy *phy)
+{
+	struct udevice *dev = phy->dev;
+	struct phy_meson_axg_mipi_dphy_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = generic_phy_exit(&priv->analog);
+	if (ret)
+		return ret;
+
+	return reset_assert(&priv->reset);
+}
+
+struct phy_ops meson_axg_mipi_dphy_ops = {
+	.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,
+	.configure = phy_meson_axg_mipi_dphy_configure,
+};
+
+int meson_axg_mipi_dphy_probe(struct udevice *dev)
+{
+	struct phy_meson_axg_mipi_dphy_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = regmap_init_mem(dev_ofnode(dev), &priv->regmap);
+	if (ret)
+		return ret;
+
+	ret = generic_phy_get_by_index(dev, 0, &priv->analog);
+	if (ret)
+		return ret;
+
+	ret = reset_get_by_index(dev, 0, &priv->reset);
+	if (ret == -ENOTSUPP)
+		return 0;
+	else if (ret)
+		return ret;
+
+	ret = reset_deassert(&priv->reset);
+	if (ret) {
+		reset_release_all(&priv->reset, 1);
+		return ret;
+	}
+
+#if CONFIG_IS_ENABLED(CLK)
+	ret = clk_get_by_index(dev, 0, &priv->clk);
+	if (ret < 0)
+		return ret;
+
+	ret = clk_enable(&priv->clk);
+	if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
+		pr_err("failed to enable PHY clock\n");
+		clk_free(&priv->clk);
+		return ret;
+	}
+#endif
+
+	return 0;
+}
+
+static const struct udevice_id meson_axg_mipi_dphy_ids[] = {
+	{ .compatible = "amlogic,axg-mipi-dphy" },
+	{ }
+};
+
+U_BOOT_DRIVER(meson_axg_mipi_dphy) = {
+	.name = "meson_axg_mipi_dphy",
+	.id = UCLASS_PHY,
+	.of_match = meson_axg_mipi_dphy_ids,
+	.probe = meson_axg_mipi_dphy_probe,
+	.ops = &meson_axg_mipi_dphy_ops,
+	.priv_auto_alloc_size = sizeof(struct phy_meson_axg_mipi_dphy_priv),
+};