[PATCH V4 net-next 6/8] net: hns3: Add MDIO support to HNS3 Ethernet driver for hip08 SoC

[Salil Mehta <salil.mehta@huawei.com>]

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@hisilicon.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: Yisen Zhuang <yisen.zhuang@huawei.com>
---
Patch V4: Addressed following comments:
 1. Andrew Lunn:
    https://lkml.org/lkml/2017/6/17/208
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    | 230 +++++++++++++++++++++
 1 file changed, 230 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 000000000000..6036a97f7de5
--- /dev/null
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mdio.c
@@ -0,0 +1,230 @@
+/*
+ * 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_B		0
+#define HCLGE_MDIO_CTRL_ST_S		1
+#define HCLGE_MDIO_CTRL_ST_M		(0x3 << HCLGE_MDIO_CTRL_ST_S)
+#define HCLGE_MDIO_CTRL_OP_S		3
+#define HCLGE_MDIO_CTRL_OP_M		(0x3 << HCLGE_MDIO_CTRL_OP_S)
+
+#define HCLGE_MDIO_PHYID_S		0
+#define HCLGE_MDIO_PHYID_M		(0x1f << HCLGE_MDIO_PHYID_S)
+
+#define HCLGE_MDIO_PHYREG_S		0
+#define HCLGE_MDIO_PHYREG_M		(0x1f << HCLGE_MDIO_PHYREG_S)
+
+#define HCLGE_MDIO_STA_B		0
+
+struct hclge_mdio_cfg_cmd {
+	u8 ctrl_bit;
+	u8 phyid;
+	u8 phyad;
+	u8 rsvd;
+	__le16 reserve;
+	__le16 data_wr;
+	__le16 data_rd;
+	__le16 sta;
+};
+
+static int hclge_mdio_write(struct mii_bus *bus, int phyid, 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;
+
+	if (!bus)
+		return -EINVAL;
+
+	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_MDIO_CONFIG, false);
+
+	mdio_cmd = (struct hclge_mdio_cfg_cmd *)desc.data;
+
+	hnae_set_field(mdio_cmd->phyid, HCLGE_MDIO_PHYID_M,
+		       HCLGE_MDIO_PHYID_S, phyid);
+	hnae_set_field(mdio_cmd->phyad, HCLGE_MDIO_PHYREG_M,
+		       HCLGE_MDIO_PHYREG_S, regnum);
+
+	hnae_set_bit(mdio_cmd->ctrl_bit, HCLGE_MDIO_CTRL_START_B, 1);
+	hnae_set_field(mdio_cmd->ctrl_bit, HCLGE_MDIO_CTRL_ST_M,
+		       HCLGE_MDIO_CTRL_ST_S, 1);
+	hnae_set_field(mdio_cmd->ctrl_bit, HCLGE_MDIO_CTRL_OP_M,
+		       HCLGE_MDIO_CTRL_OP_S, HCLGE_MDIO_C22_WRITE);
+
+	mdio_cmd->data_wr = cpu_to_le16(data);
+
+	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 phyid, 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;
+
+	if (!bus)
+		return -EINVAL;
+
+	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_MDIO_CONFIG, true);
+
+	mdio_cmd = (struct hclge_mdio_cfg_cmd *)desc.data;
+
+	hnae_set_field(mdio_cmd->phyid, HCLGE_MDIO_PHYID_M,
+		       HCLGE_MDIO_PHYID_S, phyid);
+	hnae_set_field(mdio_cmd->phyad, HCLGE_MDIO_PHYREG_M,
+		       HCLGE_MDIO_PHYREG_S, regnum);
+
+	hnae_set_bit(mdio_cmd->ctrl_bit, HCLGE_MDIO_CTRL_START_B, 1);
+	hnae_set_field(mdio_cmd->ctrl_bit, HCLGE_MDIO_CTRL_ST_M,
+		       HCLGE_MDIO_CTRL_ST_S, 1);
+	hnae_set_field(mdio_cmd->ctrl_bit, HCLGE_MDIO_CTRL_OP_M,
+		       HCLGE_MDIO_CTRL_OP_S, HCLGE_MDIO_C22_READ);
+
+	/* 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 (hnae_get_bit(le16_to_cpu(mdio_cmd->sta), HCLGE_MDIO_STA_B)) {
+		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 phy_device *phydev;
+	struct mii_bus *mdio_bus;
+	int ret;
+
+	if (hdev->hw.mac.phy_addr >= PHY_MAX_ADDR)
+		return 0;
+
+	mdio_bus = devm_mdiobus_alloc(&hdev->pdev->dev);
+	if (!mdio_bus)
+		return -ENOMEM;
+
+	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);
+		return ret;
+	}
+
+	phydev = mdiobus_get_phy(mdio_bus, mac->phy_addr);
+	if (!phydev || IS_ERR(phydev)) {
+		dev_err(mdio_bus->parent, "Failed to get phy device\n");
+		mdiobus_unregister(mdio_bus);
+		return -EIO;
+	}
+
+	mac->phydev = phydev;
+	mac->mdio_bus = mdio_bus;
+
+	return 0;
+}
+
+static void hclge_mac_adjust_link(struct net_device *netdev)
+{
+	struct hclge_mac *hw_mac;
+	struct hclge_dev *hdev;
+	struct hclge_hw *hw;
+	int duplex;
+	int speed;
+
+	if (!netdev)
+		return;
+
+	hw_mac = container_of(netdev, struct hclge_mac, netdev);
+	hw = container_of(hw_mac, struct hclge_hw, mac);
+	hdev = hw->back;
+
+	speed = netdev->phydev->speed;
+	duplex = netdev->phydev->duplex;
+
+	/* update antoneg. */
+	hw_mac->autoneg = netdev->phydev->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 net_device *netdev = &mac->netdev;
+	struct phy_device *phydev = mac->phydev;
+	int ret;
+
+	if (!phydev)
+		return 0;
+
+	phydev->dev_flags = 0;
+
+	ret = phy_connect_direct(netdev, phydev,
+				 hclge_mac_adjust_link,
+				 PHY_INTERFACE_MODE_SGMII);
+	if (ret) {
+		pr_info("phy_connect_direct err");
+		return ret;
+	}
+
+	phy_start(phydev);
+
+	return 0;
+}
+
+void hclge_mac_stop_phy(struct hclge_dev *hdev)
+{
+	struct hclge_mac *mac = &hdev->hw.mac;
+	struct net_device *netdev = &mac->netdev;
+	struct phy_device *phydev = netdev->phydev;
+
+	if (!phydev)
+		return;
+
+	phy_disconnect(phydev);
+}
-- 
2.11.0