phy: add A3700 COMPHY support

Add a driver to support COMPHY, a hardware block providing shared
serdes PHYs on Marvell Armada 3700. This driver uses SMC calls and
rely on having an up-to-date firmware.

SATA, PCie and USB3 host mode have been tested successfully with an
ESPRESSObin. (HS)SGMII mode cannot be tested with this platform.

Evan worked on the original driver structure and Grzegorz on the SMC
calls rework. The structure of this driver has been copied from
Antoine Tenart work on CP110 COMPHY driver.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Co-developed-by: Evan Wang <xswang@marvell.com>
Signed-off-by: Evan Wang <xswang@marvell.com>
Co-developed-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

drivers/phy/marvell/Kconfig

@@ -21,6 +21,18 @@ config PHY_BERLIN_USB
 	help
 	  Enable this to support the USB PHY on Marvell Berlin SoCs.
 
+config PHY_MVEBU_A3700_COMPHY
+	tristate "Marvell A3700 comphy driver"
+	depends on ARCH_MVEBU || COMPILE_TEST
+	depends on OF
+	depends on HAVE_ARM_SMCCC
+	default y
+	select GENERIC_PHY
+	help
+	  This driver allows to control the comphy, a hardware block providing
+	  shared serdes PHYs on Marvell Armada 3700. Its serdes lanes can be
+	  used by various controllers: Ethernet, SATA, USB3, PCIe.
+
 config PHY_MVEBU_CP110_COMPHY
 	tristate "Marvell CP110 comphy driver"
 	depends on ARCH_MVEBU || COMPILE_TEST

drivers/phy/marvell/Makefile

@@ -2,6 +2,7 @@
 obj-$(CONFIG_ARMADA375_USBCLUSTER_PHY)	+= phy-armada375-usb2.o
 obj-$(CONFIG_PHY_BERLIN_SATA)		+= phy-berlin-sata.o
 obj-$(CONFIG_PHY_BERLIN_USB)		+= phy-berlin-usb.o
+obj-$(CONFIG_PHY_MVEBU_A3700_COMPHY)	+= phy-mvebu-a3700-comphy.o
 obj-$(CONFIG_PHY_MVEBU_CP110_COMPHY)	+= phy-mvebu-cp110-comphy.o
 obj-$(CONFIG_PHY_MVEBU_SATA)		+= phy-mvebu-sata.o
 obj-$(CONFIG_PHY_PXA_28NM_HSIC)		+= phy-pxa-28nm-hsic.o

drivers/phy/marvell/phy-mvebu-a3700-comphy.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Marvell
+ *
+ * Authors:
+ *   Evan Wang <xswang@marvell.com>
+ *   Miquèl Raynal <miquel.raynal@bootlin.com>
+ *
+ * Structure inspired from phy-mvebu-cp110-comphy.c written by Antoine Tenart.
+ * SMC call initial support done by Grzegorz Jaszczyk.
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+
+#define MVEBU_A3700_COMPHY_LANES		3
+#define MVEBU_A3700_COMPHY_PORTS		2
+
+/* COMPHY Fast SMC function identifiers */
+#define COMPHY_SIP_POWER_ON			0x82000001
+#define COMPHY_SIP_POWER_OFF			0x82000002
+#define COMPHY_SIP_PLL_LOCK			0x82000003
+
+#define COMPHY_FW_MODE_SATA			0x1
+#define COMPHY_FW_MODE_SGMII			0x2
+#define COMPHY_FW_MODE_HS_SGMII			0x3
+#define COMPHY_FW_MODE_USB3H			0x4
+#define COMPHY_FW_MODE_USB3D			0x5
+#define COMPHY_FW_MODE_PCIE			0x6
+#define COMPHY_FW_MODE_RXAUI			0x7
+#define COMPHY_FW_MODE_XFI			0x8
+#define COMPHY_FW_MODE_SFI			0x9
+#define COMPHY_FW_MODE_USB3			0xa
+
+#define COMPHY_FW_SPEED_1_25G			0 /* SGMII 1G */
+#define COMPHY_FW_SPEED_2_5G			1
+#define COMPHY_FW_SPEED_3_125G			2 /* SGMII 2.5G */
+#define COMPHY_FW_SPEED_5G			3
+#define COMPHY_FW_SPEED_5_15625G		4 /* XFI 5G */
+#define COMPHY_FW_SPEED_6G			5
+#define COMPHY_FW_SPEED_10_3125G		6 /* XFI 10G */
+#define COMPHY_FW_SPEED_MAX			0x3F
+
+#define COMPHY_FW_MODE(mode)			((mode) << 12)
+#define COMPHY_FW_NET(mode, idx, speed)		(COMPHY_FW_MODE(mode) | \
+						 ((idx) << 8) |	\
+						 ((speed) << 2))
+#define COMPHY_FW_PCIE(mode, idx, speed, width)	(COMPHY_FW_NET(mode, idx, speed) | \
+						 ((width) << 18))
+
+struct mvebu_a3700_comphy_conf {
+	unsigned int lane;
+	enum phy_mode mode;
+	int submode;
+	unsigned int port;
+	u32 fw_mode;
+};
+
+#define MVEBU_A3700_COMPHY_CONF(_lane, _mode, _smode, _port, _fw)	\
+	{								\
+		.lane = _lane,						\
+		.mode = _mode,						\
+		.submode = _smode,					\
+		.port = _port,						\
+		.fw_mode = _fw,						\
+	}
+
+#define MVEBU_A3700_COMPHY_CONF_GEN(_lane, _mode, _port, _fw) \
+	MVEBU_A3700_COMPHY_CONF(_lane, _mode, PHY_INTERFACE_MODE_NA, _port, _fw)
+
+#define MVEBU_A3700_COMPHY_CONF_ETH(_lane, _smode, _port, _fw) \
+	MVEBU_A3700_COMPHY_CONF(_lane, PHY_MODE_ETHERNET, _smode, _port, _fw)
+
+static const struct mvebu_a3700_comphy_conf mvebu_a3700_comphy_modes[] = {
+	/* lane 0 */
+	MVEBU_A3700_COMPHY_CONF_GEN(0, PHY_MODE_USB_HOST_SS, 0,
+				    COMPHY_FW_MODE_USB3H),
+	MVEBU_A3700_COMPHY_CONF_ETH(0, PHY_INTERFACE_MODE_SGMII, 1,
+				    COMPHY_FW_MODE_SGMII),
+	MVEBU_A3700_COMPHY_CONF_ETH(0, PHY_INTERFACE_MODE_2500BASEX, 1,
+				    COMPHY_FW_MODE_HS_SGMII),
+	/* lane 1 */
+	MVEBU_A3700_COMPHY_CONF_GEN(1, PHY_MODE_PCIE, 0,
+				    COMPHY_FW_MODE_PCIE),
+	MVEBU_A3700_COMPHY_CONF_ETH(1, PHY_INTERFACE_MODE_SGMII, 0,
+				    COMPHY_FW_MODE_SGMII),
+	MVEBU_A3700_COMPHY_CONF_ETH(1, PHY_INTERFACE_MODE_2500BASEX, 0,
+				    COMPHY_FW_MODE_HS_SGMII),
+	/* lane 2 */
+	MVEBU_A3700_COMPHY_CONF_GEN(2, PHY_MODE_SATA, 0,
+				    COMPHY_FW_MODE_SATA),
+	MVEBU_A3700_COMPHY_CONF_GEN(2, PHY_MODE_USB_HOST_SS, 0,
+				    COMPHY_FW_MODE_USB3H),
+};
+
+struct mvebu_a3700_comphy_lane {
+	struct device *dev;
+	unsigned int id;
+	enum phy_mode mode;
+	int submode;
+	int port;
+};
+
+static int mvebu_a3700_comphy_smc(unsigned long function, unsigned long lane,
+				  unsigned long mode)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(function, lane, mode, 0, 0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
+static int mvebu_a3700_comphy_get_fw_mode(int lane, int port,
+					  enum phy_mode mode,
+					  int submode)
+{
+	int i, n = ARRAY_SIZE(mvebu_a3700_comphy_modes);
+
+	/* Unused PHY mux value is 0x0 */
+	if (mode == PHY_MODE_INVALID)
+		return -EINVAL;
+
+	for (i = 0; i < n; i++) {
+		if (mvebu_a3700_comphy_modes[i].lane == lane &&
+		    mvebu_a3700_comphy_modes[i].port == port &&
+		    mvebu_a3700_comphy_modes[i].mode == mode &&
+		    mvebu_a3700_comphy_modes[i].submode == submode)
+			break;
+	}
+
+	if (i == n)
+		return -EINVAL;
+
+	return mvebu_a3700_comphy_modes[i].fw_mode;
+}
+
+static int mvebu_a3700_comphy_set_mode(struct phy *phy, enum phy_mode mode,
+				       int submode)
+{
+	struct mvebu_a3700_comphy_lane *lane = phy_get_drvdata(phy);
+	int fw_mode;
+
+	if (submode == PHY_INTERFACE_MODE_1000BASEX)
+		submode = PHY_INTERFACE_MODE_SGMII;
+
+	fw_mode = mvebu_a3700_comphy_get_fw_mode(lane->id, lane->port, mode,
+						 submode);
+	if (fw_mode < 0) {
+		dev_err(lane->dev, "invalid COMPHY mode\n");
+		return fw_mode;
+	}
+
+	/* Just remember the mode, ->power_on() will do the real setup */
+	lane->mode = mode;
+	lane->submode = submode;
+
+	return 0;
+}
+
+static int mvebu_a3700_comphy_power_on(struct phy *phy)
+{
+	struct mvebu_a3700_comphy_lane *lane = phy_get_drvdata(phy);
+	u32 fw_param;
+	int fw_mode;
+
+	fw_mode = mvebu_a3700_comphy_get_fw_mode(lane->id, lane->port,
+						 lane->mode, lane->submode);
+	if (fw_mode < 0) {
+		dev_err(lane->dev, "invalid COMPHY mode\n");
+		return fw_mode;
+	}
+
+	switch (lane->mode) {
+	case PHY_MODE_USB_HOST_SS:
+		dev_dbg(lane->dev, "set lane %d to USB3 host mode\n", lane->id);
+		fw_param = COMPHY_FW_MODE(fw_mode);
+		break;
+	case PHY_MODE_SATA:
+		dev_dbg(lane->dev, "set lane %d to SATA mode\n", lane->id);
+		fw_param = COMPHY_FW_MODE(fw_mode);
+		break;
+	case PHY_MODE_ETHERNET:
+		switch (lane->submode) {
+		case PHY_INTERFACE_MODE_SGMII:
+			dev_dbg(lane->dev, "set lane %d to SGMII mode\n",
+				lane->id);
+			fw_param = COMPHY_FW_NET(fw_mode, lane->port,
+						 COMPHY_FW_SPEED_1_25G);
+			break;
+		case PHY_INTERFACE_MODE_2500BASEX:
+			dev_dbg(lane->dev, "set lane %d to HS SGMII mode\n",
+				lane->id);
+			fw_param = COMPHY_FW_NET(fw_mode, lane->port,
+						 COMPHY_FW_SPEED_3_125G);
+			break;
+		default:
+			dev_err(lane->dev, "unsupported PHY submode (%d)\n",
+				lane->submode);
+			return -ENOTSUPP;
+		}
+		break;
+	case PHY_MODE_PCIE:
+		dev_dbg(lane->dev, "set lane %d to PCIe mode\n", lane->id);
+		fw_param = COMPHY_FW_PCIE(fw_mode, lane->port,
+					  COMPHY_FW_SPEED_5G,
+					  phy->attrs.bus_width);
+		break;
+	default:
+		dev_err(lane->dev, "unsupported PHY mode (%d)\n", lane->mode);
+		return -ENOTSUPP;
+	}
+
+	return mvebu_a3700_comphy_smc(COMPHY_SIP_POWER_ON, lane->id, fw_param);
+}
+
+static int mvebu_a3700_comphy_power_off(struct phy *phy)
+{
+	struct mvebu_a3700_comphy_lane *lane = phy_get_drvdata(phy);
+
+	return mvebu_a3700_comphy_smc(COMPHY_SIP_POWER_OFF, lane->id, 0);
+}
+
+static const struct phy_ops mvebu_a3700_comphy_ops = {
+	.power_on	= mvebu_a3700_comphy_power_on,
+	.power_off	= mvebu_a3700_comphy_power_off,
+	.set_mode	= mvebu_a3700_comphy_set_mode,
+	.owner		= THIS_MODULE,
+};
+
+static struct phy *mvebu_a3700_comphy_xlate(struct device *dev,
+					    struct of_phandle_args *args)
+{
+	struct mvebu_a3700_comphy_lane *lane;
+	struct phy *phy;
+
+	if (WARN_ON(args->args[0] >= MVEBU_A3700_COMPHY_PORTS))
+		return ERR_PTR(-EINVAL);
+
+	phy = of_phy_simple_xlate(dev, args);
+	if (IS_ERR(phy))
+		return phy;
+
+	lane = phy_get_drvdata(phy);
+	lane->port = args->args[0];
+
+	return phy;
+}
+
+static int mvebu_a3700_comphy_probe(struct platform_device *pdev)
+{
+	struct phy_provider *provider;
+	struct device_node *child;
+
+	for_each_available_child_of_node(pdev->dev.of_node, child) {
+		struct mvebu_a3700_comphy_lane *lane;
+		struct phy *phy;
+		int ret;
+		u32 lane_id;
+
+		ret = of_property_read_u32(child, "reg", &lane_id);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "missing 'reg' property (%d)\n",
+				ret);
+			continue;
+		}
+
+		if (lane_id >= MVEBU_A3700_COMPHY_LANES) {
+			dev_err(&pdev->dev, "invalid 'reg' property\n");
+			continue;
+		}
+
+		lane = devm_kzalloc(&pdev->dev, sizeof(*lane), GFP_KERNEL);
+		if (!lane)
+			return -ENOMEM;
+
+		phy = devm_phy_create(&pdev->dev, child,
+				      &mvebu_a3700_comphy_ops);
+		if (IS_ERR(phy))
+			return PTR_ERR(phy);
+
+		lane->dev = &pdev->dev;
+		lane->mode = PHY_MODE_INVALID;
+		lane->submode = PHY_INTERFACE_MODE_NA;
+		lane->id = lane_id;
+		lane->port = -1;
+		phy_set_drvdata(phy, lane);
+	}
+
+	provider = devm_of_phy_provider_register(&pdev->dev,
+						 mvebu_a3700_comphy_xlate);
+	return PTR_ERR_OR_ZERO(provider);
+}
+
+static const struct of_device_id mvebu_a3700_comphy_of_match_table[] = {
+	{ .compatible = "marvell,comphy-a3700" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, mvebu_a3700_comphy_of_match_table);
+
+static struct platform_driver mvebu_a3700_comphy_driver = {
+	.probe	= mvebu_a3700_comphy_probe,
+	.driver	= {
+		.name = "mvebu-a3700-comphy",
+		.of_match_table = mvebu_a3700_comphy_of_match_table,
+	},
+};
+module_platform_driver(mvebu_a3700_comphy_driver);
+
+MODULE_AUTHOR("Miquèl Raynal <miquel.raynal@bootlin.com>");
+MODULE_DESCRIPTION("Common PHY driver for A3700");
+MODULE_LICENSE("GPL v2");