[PATCH V3 net-next 6/8] net: hns3: Add MDIO support to HNS3 Ethernet driver for hip08 SoC

[Salil Mehta]

This patch adds the support of MDIO bus interface for HNS3 driver.
Code provides various interfaces to start and stop the PHY layer
and to read and write the MDIO bus or PHY.

Signed-off-by: Daode Huang <huangdaode@xxxxxxxxxxxxx>
Signed-off-by: lipeng <lipeng321@xxxxxxxxxx>
Signed-off-by: Salil Mehta <salil.mehta@xxxxxxxxxx>
Signed-off-by: Yisen Zhuang <yisen.zhuang@xxxxxxxxxx>
---
Patch V3: Addressed Below comments:
 1. Florian Fainelli: https://lkml.org/lkml/2017/6/13/963
 2. Andrew Lunn: https://lkml.org/lkml/2017/6/13/1039
Patch V2: Addressed below comments:
 1. Florian Fainelli: https://lkml.org/lkml/2017/6/10/130
 2. Andrew Lunn: https://lkml.org/lkml/2017/6/10/168
Patch V1: Initial Submit
---
 .../ethernet/hisilicon/hns3/hns3pf/hclge_mdio.c    | 249 +++++++++++++++++++++
 1 file changed, 249 insertions(+)
 create mode 100644 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mdio.c

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mdio.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mdio.c
new file mode 100644
index 0000000..5b21c50
--- /dev/null
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mdio.c
@@ -0,0 +1,249 @@
+/*
+ * Copyright (c) 2016~2017 Hisilicon Limited.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/kernel.h>
+
+#include "hclge_cmd.h"
+#include "hclge_main.h"
+
+enum hclge_mdio_c22_op_seq {
+	HCLGE_MDIO_C22_WRITE = 1,
+	HCLGE_MDIO_C22_READ = 2
+};
+
+#define HCLGE_MDIO_CTRL_START_BIT       BIT(0)
+#define HCLGE_MDIO_CTRL_ST_MSK  GENMASK(2, 1)
+#define HCLGE_MDIO_CTRL_ST_LSH  1
+#define HCLGE_MDIO_IS_C22(c22)  (((c22) << HCLGE_MDIO_CTRL_ST_LSH) & \
+	HCLGE_MDIO_CTRL_ST_MSK)
+
+#define HCLGE_MDIO_CTRL_OP_MSK  GENMASK(4, 3)
+#define HCLGE_MDIO_CTRL_OP_LSH  3
+#define HCLGE_MDIO_CTRL_OP(access) \
+	(((access) << HCLGE_MDIO_CTRL_OP_LSH) &	HCLGE_MDIO_CTRL_OP_MSK)
+#define HCLGE_MDIO_CTRL_PRTAD_MSK       GENMASK(4, 0)
+#define HCLGE_MDIO_CTRL_DEVAD_MSK       GENMASK(4, 0)
+
+#define HCLGE_MDIO_STA_VAL(val)	((val) & BIT(0))
+
+struct hclge_mdio_cfg_cmd {
+	u8 ctrl_bit;
+	u8 prtad;       /* The external port address */
+	u8 devad;       /* The external device address */
+	u8 rsvd;
+	__le16 reserve;
+	__le16 data_wr;
+	__le16 data_rd;
+	__le16 sta;
+};
+
+static int hclge_mdio_write(struct mii_bus *bus, int phy_id, int regnum,
+			    u16 data)
+{
+	struct hclge_dev *hdev = (struct hclge_dev *)bus->priv;
+	struct hclge_mdio_cfg_cmd *mdio_cmd;
+	enum hclge_cmd_status status;
+	struct hclge_desc desc;
+	u8 devad;
+
+	if (!bus)
+		return -EINVAL;
+
+	devad = ((regnum >> 16) & 0x1f);
+
+	dev_dbg(&bus->dev, "phy id=%d, devad=%d\n", phy_id, devad);
+
+	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_MDIO_CONFIG, false);
+
+	mdio_cmd = (struct hclge_mdio_cfg_cmd *)desc.data;
+
+	mdio_cmd->prtad = phy_id & HCLGE_MDIO_CTRL_PRTAD_MSK;
+	mdio_cmd->data_wr = cpu_to_le16(data);
+	mdio_cmd->devad = devad & HCLGE_MDIO_CTRL_DEVAD_MSK;
+
+	/* Write reg and data */
+	mdio_cmd->ctrl_bit = HCLGE_MDIO_IS_C22(1);
+	mdio_cmd->ctrl_bit |= HCLGE_MDIO_CTRL_OP(HCLGE_MDIO_C22_WRITE);
+	mdio_cmd->ctrl_bit |= HCLGE_MDIO_CTRL_START_BIT;
+
+	status = hclge_cmd_send(&hdev->hw, &desc, 1);
+	if (status) {
+		dev_err(&hdev->pdev->dev,
+			"mdio write fail when sending cmd, status is %d.\n",
+			status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int hclge_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
+{
+	struct hclge_dev *hdev = (struct hclge_dev *)bus->priv;
+	struct hclge_mdio_cfg_cmd *mdio_cmd;
+	enum hclge_cmd_status status;
+	struct hclge_desc desc;
+	u8 devad;
+
+	if (!bus)
+		return -EINVAL;
+
+	devad = ((regnum >> 16) & GENMASK(4, 0));
+
+	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_MDIO_CONFIG, true);
+
+	mdio_cmd = (struct hclge_mdio_cfg_cmd *)desc.data;
+
+	dev_dbg(&bus->dev, "phy id=%d, devad=%d\n", phy_id, devad);
+
+	mdio_cmd->prtad = phy_id & HCLGE_MDIO_CTRL_PRTAD_MSK;
+	mdio_cmd->devad = devad & HCLGE_MDIO_CTRL_DEVAD_MSK;
+
+	/* Write reg and data */
+	mdio_cmd->ctrl_bit = HCLGE_MDIO_IS_C22(1);
+	mdio_cmd->ctrl_bit |= HCLGE_MDIO_CTRL_OP(HCLGE_MDIO_C22_WRITE);
+	mdio_cmd->ctrl_bit |= HCLGE_MDIO_CTRL_START_BIT;
+
+	/* Read out phy data */
+	status = hclge_cmd_send(&hdev->hw, &desc, 1);
+	if (status) {
+		dev_err(&hdev->pdev->dev,
+			"mdio read fail when get data, status is %d.\n",
+			status);
+		return status;
+	}
+
+	if (HCLGE_MDIO_STA_VAL(mdio_cmd->sta)) {
+		dev_err(&hdev->pdev->dev, "mdio read data error\n");
+		return -EIO;
+	}
+
+	return le16_to_cpu(mdio_cmd->data_rd);
+}
+
+int hclge_mac_mdio_config(struct hclge_dev *hdev)
+{
+	struct hclge_mac *mac = &hdev->hw.mac;
+	struct net_device *ndev = &mac->ndev;
+	struct phy_device *phy_dev;
+	struct mii_bus *mdio_bus;
+	int ret;
+
+	if (hdev->hw.mac.phy_addr >= PHY_MAX_ADDR)
+		return 0;
+
+	SET_NETDEV_DEV(ndev, &hdev->pdev->dev);
+
+	mdio_bus = devm_mdiobus_alloc(&hdev->pdev->dev);
+	if (!mdio_bus) {
+		ret = -ENOMEM;
+		goto err_miibus_alloc;
+	}
+
+	mdio_bus->name = "hisilicon MII bus";
+	mdio_bus->read = hclge_mdio_read;
+	mdio_bus->write = hclge_mdio_write;
+	snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s-%s", "mii",
+		 dev_name(&hdev->pdev->dev));
+
+	mdio_bus->parent = &hdev->pdev->dev;
+	mdio_bus->priv = hdev;
+	mdio_bus->phy_mask = ~(1 << mac->phy_addr);
+	ret = mdiobus_register(mdio_bus);
+	if (ret) {
+		dev_err(mdio_bus->parent,
+			"Failed to register MDIO bus ret = %#x\n", ret);
+		goto err_mdio_register;
+	}
+
+	phy_dev = mdiobus_get_phy(mdio_bus, mac->phy_addr);
+	if (!phy_dev || IS_ERR(phy_dev)) {
+		dev_err(mdio_bus->parent, "Failed to get phy device\n");
+		ret = -EIO;
+		goto err_mdio_register;
+	}
+
+	phy_dev->irq = mdio_bus->irq[mac->phy_addr];
+	mac->phy_dev = phy_dev;
+
+	return 0;
+
+err_mdio_register:
+	mdiobus_unregister(mdio_bus);
+	mdiobus_free(mdio_bus);
+err_miibus_alloc:
+	return ret;
+}
+
+static void hclge_mac_adjust_link(struct net_device *net_dev)
+{
+	struct hclge_mac *hw_mac;
+	struct hclge_dev *hdev;
+	struct hclge_hw *hw;
+	int duplex;
+	int speed;
+
+	if (!net_dev)
+		return;
+
+	hw_mac = container_of(net_dev, struct hclge_mac, ndev);
+	hw = container_of(hw_mac, struct hclge_hw, mac);
+	hdev = hw->back;
+
+	speed = hw_mac->phy_dev->speed;
+	duplex = hw_mac->phy_dev->duplex;
+
+	/* update antoneg. */
+	hw_mac->autoneg = hw_mac->phy_dev->autoneg;
+
+	if ((hw_mac->speed != speed) || (hw_mac->duplex != duplex))
+		(void)hclge_cfg_mac_speed_dup(hdev, speed, !!duplex);
+}
+
+int hclge_mac_start_phy(struct hclge_dev *hdev)
+{
+	struct hclge_mac *mac = &hdev->hw.mac;
+	struct phy_device *phy_dev = mac->phy_dev;
+	struct net_device *ndev = &mac->ndev;
+	int ret;
+
+	if (!phy_dev)
+		return 0;
+
+	phy_dev->dev_flags = 0;
+
+	ret = phy_connect_direct(ndev, phy_dev,
+				 hclge_mac_adjust_link,
+				 PHY_INTERFACE_MODE_SGMII);
+	if (unlikely(ret)) {
+		pr_info("phy_connect_direct err");
+		return -ENODEV;
+	}
+
+	phy_dev->supported = SUPPORTED_10baseT_Half |
+			SUPPORTED_10baseT_Full |
+			SUPPORTED_100baseT_Half |
+			SUPPORTED_100baseT_Full |
+			SUPPORTED_Autoneg |
+			SUPPORTED_1000baseT_Full;
+
+	phy_start(mac->phy_dev);
+
+	return 0;
+}
+
+void hclge_mac_stop_phy(struct hclge_dev *hdev)
+{
+	if (!hdev->hw.mac.phy_dev)
+		return;
+
+	phy_disconnect(hdev->hw.mac.phy_dev);
+	phy_stop(hdev->hw.mac.phy_dev);
+}
-- 
2.7.4