[PATCH 6/8] phy: amlogic: Add Amlogic G12A USB3 + PCIE Combo PHY Driver

From: Neil Armstrong
Date: Tue Feb 12 2019 - 10:14:48 EST


This adds support for the shared USB3 + PCIE PHY found in the
Amlogic G12A SoC Family.

It supports USB3 Host mode or PCIE 2.0 mode, depending on the layout of
the board.

Selection is done by the #phy-cells, making the mode static and exclusive.

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/phy/amlogic/Kconfig | 12 +
drivers/phy/amlogic/Makefile | 1 +
.../phy/amlogic/phy-meson-g12a-usb3-pcie.c | 414 ++++++++++++++++++
3 files changed, 427 insertions(+)
create mode 100644 drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c

diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
index 78d6e194dce9..7ccb9a756aba 100644
--- a/drivers/phy/amlogic/Kconfig
+++ b/drivers/phy/amlogic/Kconfig
@@ -48,3 +48,15 @@ config PHY_MESON_G12A_USB2
Enable this to support the Meson USB2 PHYs found in Meson
G12A SoCs.
If unsure, say N.
+
+config PHY_MESON_G12A_USB3_PCIE
+ tristate "Meson G12A USB3+PCIE Combo PHY drivers"
+ default ARCH_MESON
+ depends on OF && (ARCH_MESON || COMPILE_TEST)
+ depends on USB_SUPPORT
+ select GENERIC_PHY
+ select REGMAP_MMIO
+ help
+ Enable this to support the Meson USB3 + PCIE Combi PHY found
+ in Meson G12A SoCs.
+ If unsure, say N.
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index 7d4d10f5a6b3..fdd008e1b19b 100644
--- a/drivers/phy/amlogic/Makefile
+++ b/drivers/phy/amlogic/Makefile
@@ -2,3 +2,4 @@ obj-$(CONFIG_PHY_MESON8B_USB2) += phy-meson8b-usb2.o
obj-$(CONFIG_PHY_MESON_GXL_USB2) += phy-meson-gxl-usb2.o
obj-$(CONFIG_PHY_MESON_G12A_USB2) += phy-meson-g12a-usb2.o
obj-$(CONFIG_PHY_MESON_GXL_USB3) += phy-meson-gxl-usb3.o
+obj-$(CONFIG_PHY_MESON_G12A_USB3_PCIE) += phy-meson-g12a-usb3-pcie.o
diff --git a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
new file mode 100644
index 000000000000..59eae98928e9
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
@@ -0,0 +1,414 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Amlogic G12A USB3 + PCIE Combo PHY driver
+ *
+ * Copyright (C) 2017 Amlogic, Inc. All rights reserved
+ * Copyright (C) 2019 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/platform_device.h>
+#include <dt-bindings/phy/phy.h>
+
+#define PHY_R0 0x00
+ #define PHY_R0_PCIE_POWER_STATE GENMASK(4, 0)
+ #define PHY_R0_PCIE_USB3_SWITCH GENMASK(6, 5)
+
+#define PHY_R1 0x04
+ #define PHY_R1_PHY_TX1_TERM_OFFSET GENMASK(4, 0)
+ #define PHY_R1_PHY_TX0_TERM_OFFSET GENMASK(9, 5)
+ #define PHY_R1_PHY_RX1_EQ GENMASK(12, 10)
+ #define PHY_R1_PHY_RX0_EQ GENMASK(15, 13)
+ #define PHY_R1_PHY_LOS_LEVEL GENMASK(20, 16)
+ #define PHY_R1_PHY_LOS_BIAS GENMASK(23, 21)
+ #define PHY_R1_PHY_REF_CLKDIV2 BIT(24)
+ #define PHY_R1_PHY_MPLL_MULTIPLIER GENMASK(31, 25)
+
+#define PHY_R2 0x08
+ #define PHY_R2_PCS_TX_DEEMPH_GEN2_6DB GENMASK(5, 0)
+ #define PHY_R2_PCS_TX_DEEMPH_GEN2_3P5DB GENMASK(11, 6)
+ #define PHY_R2_PCS_TX_DEEMPH_GEN1 GENMASK(17, 12)
+ #define PHY_R2_PHY_TX_VBOOST_LVL GENMASK(20, 18)
+
+#define PHY_R4 0x10
+ #define PHY_R4_PHY_CR_WRITE BIT(0)
+ #define PHY_R4_PHY_CR_READ BIT(1)
+ #define PHY_R4_PHY_CR_DATA_IN GENMASK(17, 2)
+ #define PHY_R4_PHY_CR_CAP_DATA BIT(18)
+ #define PHY_R4_PHY_CR_CAP_ADDR BIT(19)
+
+#define PHY_R5 0x14
+ #define PHY_R5_PHY_CR_DATA_OUT GENMASK(15, 0)
+ #define PHY_R5_PHY_CR_ACK BIT(16)
+ #define PHY_R5_PHY_BS_OUT BIT(17)
+
+struct phy_g12a_usb3_pcie_priv {
+ struct regmap *regmap;
+ struct regmap *regmap_cr;
+ struct clk *clk_ref;
+ struct reset_control *reset;
+ struct phy *phy;
+ unsigned int mode;
+};
+
+static const struct regmap_config phy_g12a_usb3_pcie_regmap_conf = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = PHY_R5,
+};
+
+static int phy_g12a_usb3_pcie_cr_bus_addr(struct phy_g12a_usb3_pcie_priv *priv,
+ unsigned int addr)
+{
+ unsigned int val, reg;
+ int ret;
+
+ reg = FIELD_PREP(PHY_R4_PHY_CR_DATA_IN, addr);
+
+ regmap_write(priv->regmap, PHY_R4, reg);
+ regmap_write(priv->regmap, PHY_R4, reg);
+
+ regmap_write(priv->regmap, PHY_R4, reg | PHY_R4_PHY_CR_CAP_ADDR);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ (val & PHY_R5_PHY_CR_ACK),
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ regmap_write(priv->regmap, PHY_R4, reg);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ !(val & PHY_R5_PHY_CR_ACK),
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int phy_g12a_usb3_pcie_cr_bus_read(void *context, unsigned int addr,
+ unsigned int *data)
+{
+ struct phy_g12a_usb3_pcie_priv *priv = context;
+ unsigned int val;
+ int ret;
+
+ ret = phy_g12a_usb3_pcie_cr_bus_addr(priv, addr);
+ if (ret)
+ return ret;
+
+ regmap_write(priv->regmap, PHY_R4, 0);
+ regmap_write(priv->regmap, PHY_R4, PHY_R4_PHY_CR_READ);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ (val & PHY_R5_PHY_CR_ACK),
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ *data = FIELD_GET(PHY_R5_PHY_CR_DATA_OUT, val);
+
+ regmap_write(priv->regmap, PHY_R4, 0);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ !(val & PHY_R5_PHY_CR_ACK),
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int phy_g12a_usb3_pcie_cr_bus_write(void *context, unsigned int addr,
+ unsigned int data)
+{
+ struct phy_g12a_usb3_pcie_priv *priv = context;
+ unsigned int val, reg;
+ int ret;
+
+ ret = phy_g12a_usb3_pcie_cr_bus_addr(priv, addr);
+ if (ret)
+ return ret;
+
+ reg = FIELD_PREP(PHY_R4_PHY_CR_DATA_IN, data);
+
+ regmap_write(priv->regmap, PHY_R4, reg);
+ regmap_write(priv->regmap, PHY_R4, reg);
+
+ regmap_write(priv->regmap, PHY_R4, reg | PHY_R4_PHY_CR_CAP_DATA);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ (val & PHY_R5_PHY_CR_ACK),
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ regmap_write(priv->regmap, PHY_R4, reg);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ (val & PHY_R5_PHY_CR_ACK) == 0,
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ regmap_write(priv->regmap, PHY_R4, reg);
+
+ regmap_write(priv->regmap, PHY_R4, reg | PHY_R4_PHY_CR_WRITE);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ (val & PHY_R5_PHY_CR_ACK),
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ regmap_write(priv->regmap, PHY_R4, reg);
+
+ ret = regmap_read_poll_timeout(priv->regmap, PHY_R5, val,
+ (val & PHY_R5_PHY_CR_ACK) == 0,
+ 5, 1000);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static const struct regmap_config phy_g12a_usb3_pcie_cr_regmap_conf = {
+ .reg_bits = 16,
+ .val_bits = 16,
+ .reg_read = phy_g12a_usb3_pcie_cr_bus_read,
+ .reg_write = phy_g12a_usb3_pcie_cr_bus_write,
+ .max_register = 0xffff,
+ .fast_io = true,
+};
+
+static int phy_g12a_usb3_init(struct phy *phy)
+{
+ struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
+ int data, ret;
+
+ /* Switch PHY to USB3 */
+ regmap_update_bits(priv->regmap, PHY_R0,
+ PHY_R0_PCIE_USB3_SWITCH,
+ PHY_R0_PCIE_USB3_SWITCH);
+
+ /*
+ * WORKAROUND: There is SSPHY suspend bug due to
+ * which USB enumerates
+ * in HS mode instead of SS mode. Workaround it by asserting
+ * LANE0.TX_ALT_BLOCK.EN_ALT_BUS to enable TX to use alt bus
+ * mode
+ */
+ ret = regmap_update_bits(priv->regmap_cr, 0x102d, BIT(7), BIT(7));
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(priv->regmap_cr, 0x1010, 0xff0, 20);
+ if (ret)
+ return ret;
+
+ /*
+ * Fix RX Equalization setting as follows
+ * LANE0.RX_OVRD_IN_HI. RX_EQ_EN set to 0
+ * LANE0.RX_OVRD_IN_HI.RX_EQ_EN_OVRD set to 1
+ * LANE0.RX_OVRD_IN_HI.RX_EQ set to 3
+ * LANE0.RX_OVRD_IN_HI.RX_EQ_OVRD set to 1
+ */
+ ret = regmap_read(priv->regmap_cr, 0x1006, &data);
+ if (ret)
+ return ret;
+
+ data &= ~BIT(6);
+ data |= BIT(7);
+ data &= ~(0x7 << 8);
+ data |= (0x3 << 8);
+ data |= (1 << 11);
+ ret = regmap_write(priv->regmap_cr, 0x1006, data);
+ if (ret)
+ return ret;
+
+ /*
+ * Set EQ and TX launch amplitudes as follows
+ * LANE0.TX_OVRD_DRV_LO.PREEMPH set to 22
+ * LANE0.TX_OVRD_DRV_LO.AMPLITUDE set to 127
+ * LANE0.TX_OVRD_DRV_LO.EN set to 1.
+ */
+ ret = regmap_read(priv->regmap_cr, 0x1002, &data);
+ if (ret)
+ return ret;
+
+ data &= ~0x3f80;
+ data |= (0x16 << 7);
+ data &= ~0x7f;
+ data |= (0x7f | BIT(14));
+ ret = regmap_write(priv->regmap_cr, 0x1002, data);
+ if (ret)
+ return ret;
+
+ /*
+ * MPLL_LOOP_CTL.PROP_CNTRL = 8
+ */
+ ret = regmap_update_bits(priv->regmap_cr, 0x30, 0xf << 4, 8 << 4);
+ if (ret)
+ return ret;
+
+ regmap_update_bits(priv->regmap, PHY_R2,
+ PHY_R2_PHY_TX_VBOOST_LVL,
+ FIELD_PREP(PHY_R2_PHY_TX_VBOOST_LVL, 0x4));
+
+ regmap_update_bits(priv->regmap, PHY_R1,
+ PHY_R1_PHY_LOS_BIAS | PHY_R1_PHY_LOS_LEVEL,
+ FIELD_PREP(PHY_R1_PHY_LOS_BIAS, 4) |
+ FIELD_PREP(PHY_R1_PHY_LOS_LEVEL, 9));
+
+ return 0;
+}
+
+static int phy_g12a_usb3_pcie_init(struct phy *phy)
+{
+ struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ ret = reset_control_reset(priv->reset);
+ if (ret)
+ return ret;
+
+ if (priv->mode == PHY_TYPE_USB3)
+ return phy_g12a_usb3_init(phy);
+
+ /* Power UP PCIE */
+ regmap_update_bits(priv->regmap, PHY_R0,
+ PHY_R0_PCIE_POWER_STATE,
+ FIELD_PREP(PHY_R0_PCIE_POWER_STATE, 0x1c));
+
+ return 0;
+}
+
+static int phy_g12a_usb3_pcie_exit(struct phy *phy)
+{
+ struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ return reset_control_reset(priv->reset);
+}
+
+static struct phy *phy_g12a_usb3_pcie_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct phy_g12a_usb3_pcie_priv *priv = dev_get_drvdata(dev);
+ unsigned int mode;
+
+ if (args->args_count < 1) {
+ dev_err(dev, "invalid number of arguments\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ mode = args->args[0];
+
+ if (mode != PHY_TYPE_USB3 && mode != PHY_TYPE_PCIE) {
+ dev_err(dev, "invalid phy mode select argument\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ priv->mode = mode;
+
+ return priv->phy;
+}
+
+static const struct phy_ops phy_g12a_usb3_pcie_ops = {
+ .init = phy_g12a_usb3_pcie_init,
+ .exit = phy_g12a_usb3_pcie_exit,
+ .owner = THIS_MODULE,
+};
+
+static int phy_g12a_usb3_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct phy_g12a_usb3_pcie_priv *priv;
+ struct resource *res;
+ struct phy_provider *phy_provider;
+ void __iomem *base;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ 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_g12a_usb3_pcie_regmap_conf);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ priv->regmap_cr = devm_regmap_init(dev, NULL, priv,
+ &phy_g12a_usb3_pcie_cr_regmap_conf);
+ if (IS_ERR(priv->regmap_cr))
+ return PTR_ERR(priv->regmap_cr);
+
+ priv->clk_ref = devm_clk_get(dev, "ref_clk");
+ if (IS_ERR(priv->clk_ref))
+ return PTR_ERR(priv->clk_ref);
+
+ ret = clk_prepare_enable(priv->clk_ref);
+ if (ret)
+ goto err_disable_clk_ref;
+
+ priv->reset = devm_reset_control_array_get(dev, false, false);
+ if (IS_ERR(priv->reset))
+ return PTR_ERR(priv->reset);
+
+ priv->phy = devm_phy_create(dev, np, &phy_g12a_usb3_pcie_ops);
+ if (IS_ERR(priv->phy)) {
+ ret = PTR_ERR(priv->phy);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to create PHY\n");
+
+ return ret;
+ }
+
+ phy_set_drvdata(priv->phy, priv);
+ dev_set_drvdata(dev, priv);
+
+ phy_provider = devm_of_phy_provider_register(dev,
+ phy_g12a_usb3_pcie_xlate);
+
+ return PTR_ERR_OR_ZERO(phy_provider);
+
+err_disable_clk_ref:
+ clk_disable_unprepare(priv->clk_ref);
+
+ return ret;
+}
+
+static const struct of_device_id phy_g12a_usb3_pcie_of_match[] = {
+ { .compatible = "amlogic,g12a-usb3-pcie-phy", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, phy_g12a_usb3_pcie_of_match);
+
+static struct platform_driver phy_g12a_usb3_pcie_driver = {
+ .probe = phy_g12a_usb3_pcie_probe,
+ .driver = {
+ .name = "phy-g12a-usb3-pcie",
+ .of_match_table = phy_g12a_usb3_pcie_of_match,
+ },
+};
+module_platform_driver(phy_g12a_usb3_pcie_driver);
+
+MODULE_AUTHOR("Neil Armstrong <narmstrong@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Amlogic G12A USB3 + PCIE Combo PHY driver");
+MODULE_LICENSE("GPL v2");
--
2.20.1