net: emac: emac gigabit ethernet controller driver
Add support for the Qualcomm Technologies, Inc. EMAC gigabit Ethernet
controller.
This driver supports the following features:
1) Checksum offload.
2) Interrupt coalescing support.
3) SGMII phy.
4) phylib interface for external phy
Based on original work by
Niranjana Vishwanathapura <nvishwan@codeaurora.org>
Gilad Avidov <gavidov@codeaurora.org>
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-phy.c b/drivers/net/ethernet/qualcomm/emac/emac-phy.c
new file mode 100644
index 0000000..c412ba9
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/emac/emac-phy.c
@@ -0,0 +1,204 @@
+/* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+/* Qualcomm Technologies, Inc. EMAC PHY Controller driver.
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_net.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/iopoll.h>
+#include "emac.h"
+#include "emac-mac.h"
+#include "emac-phy.h"
+#include "emac-sgmii.h"
+
+/* EMAC base register offsets */
+#define EMAC_MDIO_CTRL 0x001414
+#define EMAC_PHY_STS 0x001418
+#define EMAC_MDIO_EX_CTRL 0x001440
+
+/* EMAC_MDIO_CTRL */
+#define MDIO_MODE BIT(30)
+#define MDIO_PR BIT(29)
+#define MDIO_AP_EN BIT(28)
+#define MDIO_BUSY BIT(27)
+#define MDIO_CLK_SEL_BMSK 0x7000000
+#define MDIO_CLK_SEL_SHFT 24
+#define MDIO_START BIT(23)
+#define SUP_PREAMBLE BIT(22)
+#define MDIO_RD_NWR BIT(21)
+#define MDIO_REG_ADDR_BMSK 0x1f0000
+#define MDIO_REG_ADDR_SHFT 16
+#define MDIO_DATA_BMSK 0xffff
+#define MDIO_DATA_SHFT 0
+
+/* EMAC_PHY_STS */
+#define PHY_ADDR_BMSK 0x1f0000
+#define PHY_ADDR_SHFT 16
+
+#define MDIO_CLK_25_4 0
+#define MDIO_CLK_25_28 7
+
+#define MDIO_WAIT_TIMES 1000
+
+#define EMAC_LINK_SPEED_DEFAULT (\
+ EMAC_LINK_SPEED_10_HALF |\
+ EMAC_LINK_SPEED_10_FULL |\
+ EMAC_LINK_SPEED_100_HALF |\
+ EMAC_LINK_SPEED_100_FULL |\
+ EMAC_LINK_SPEED_1GB_FULL)
+
+/**
+ * emac_phy_mdio_autopoll_disable() - disable mdio autopoll
+ * @adpt: the emac adapter
+ *
+ * The autopoll feature takes over the MDIO bus. In order for
+ * the PHY driver to be able to talk to the PHY over the MDIO
+ * bus, we need to temporarily disable the autopoll feature.
+ */
+static int emac_phy_mdio_autopoll_disable(struct emac_adapter *adpt)
+{
+ u32 val;
+
+ /* disable autopoll */
+ emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, MDIO_AP_EN, 0);
+
+ /* wait for any mdio polling to complete */
+ if (!readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, val,
+ !(val & MDIO_BUSY), 100, MDIO_WAIT_TIMES * 100))
+ return 0;
+
+ /* failed to disable; ensure it is enabled before returning */
+ emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, 0, MDIO_AP_EN);
+
+ return -EBUSY;
+}
+
+/**
+ * emac_phy_mdio_autopoll_disable() - disable mdio autopoll
+ * @adpt: the emac adapter
+ *
+ * The EMAC has the ability to poll the external PHY on the MDIO
+ * bus for link state changes. This eliminates the need for the
+ * driver to poll the phy. If if the link state does change,
+ * the EMAC issues an interrupt on behalf of the PHY.
+ */
+static void emac_phy_mdio_autopoll_enable(struct emac_adapter *adpt)
+{
+ emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, 0, MDIO_AP_EN);
+}
+
+static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum)
+{
+ struct emac_adapter *adpt = bus->priv;
+ u32 reg;
+ int ret;
+
+ ret = emac_phy_mdio_autopoll_disable(adpt);
+ if (ret)
+ return ret;
+
+ emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK,
+ (addr << PHY_ADDR_SHFT));
+
+ reg = SUP_PREAMBLE |
+ ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) |
+ ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) |
+ MDIO_START | MDIO_RD_NWR;
+
+ writel(reg, adpt->base + EMAC_MDIO_CTRL);
+
+ if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
+ !(reg & (MDIO_START | MDIO_BUSY)),
+ 100, MDIO_WAIT_TIMES * 100))
+ ret = -EIO;
+ else
+ ret = (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK;
+
+ emac_phy_mdio_autopoll_enable(adpt);
+
+ return ret;
+}
+
+static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
+{
+ struct emac_adapter *adpt = bus->priv;
+ u32 reg;
+ int ret;
+
+ ret = emac_phy_mdio_autopoll_disable(adpt);
+ if (ret)
+ return ret;
+
+ emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK,
+ (addr << PHY_ADDR_SHFT));
+
+ reg = SUP_PREAMBLE |
+ ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) |
+ ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) |
+ ((val << MDIO_DATA_SHFT) & MDIO_DATA_BMSK) |
+ MDIO_START;
+
+ writel(reg, adpt->base + EMAC_MDIO_CTRL);
+
+ if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
+ !(reg & (MDIO_START | MDIO_BUSY)), 100,
+ MDIO_WAIT_TIMES * 100))
+ ret = -EIO;
+
+ emac_phy_mdio_autopoll_enable(adpt);
+
+ return ret;
+}
+
+/* Configure the MDIO bus and connect the external PHY */
+int emac_phy_config(struct platform_device *pdev, struct emac_adapter *adpt)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *phy_np;
+ struct mii_bus *mii_bus;
+ int ret;
+
+ /* Create the mii_bus object for talking to the MDIO bus */
+ adpt->mii_bus = mii_bus = devm_mdiobus_alloc(&pdev->dev);
+ if (!mii_bus)
+ return -ENOMEM;
+
+ mii_bus->name = "emac-mdio";
+ snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
+ mii_bus->read = emac_mdio_read;
+ mii_bus->write = emac_mdio_write;
+ mii_bus->parent = &pdev->dev;
+ mii_bus->priv = adpt;
+
+ ret = of_mdiobus_register(mii_bus, np);
+ if (ret) {
+ dev_err(&pdev->dev, "could not register mdio bus\n");
+ return ret;
+ }
+
+ phy_np = of_parse_phandle(np, "phy-handle", 0);
+ adpt->phydev = of_phy_find_device(phy_np);
+ if (!adpt->phydev) {
+ dev_err(&pdev->dev, "could not find external phy\n");
+ mdiobus_unregister(mii_bus);
+ return -ENODEV;
+ }
+
+ if (adpt->phydev->drv)
+ phy_attached_print(adpt->phydev, NULL);
+
+ return 0;
+}