1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sunplus/spl2sw_mdio.c b/drivers/net/ethernet/sunplus/spl2sw_mdio.c
new file mode 100644
index 000000000000..733ae1704269
--- /dev/null
+++ b/drivers/net/ethernet/sunplus/spl2sw_mdio.c
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright Sunplus Technology Co., Ltd.
+ *       All rights reserved.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/netdevice.h>
+#include <linux/bitfield.h>
+#include <linux/of_mdio.h>
+
+#include "spl2sw_register.h"
+#include "spl2sw_define.h"
+#include "spl2sw_mdio.h"
+
+#define SPL2SW_MDIO_READ_CMD           0x02
+#define SPL2SW_MDIO_WRITE_CMD          0x01
+
+static int spl2sw_mdio_access(struct spl2sw_common *comm, u8 cmd, u8 addr, u8 regnum, u16 wdata)
+{
+	u32 reg, reg2;
+	u32 val;
+	int ret;
+
+	/* Note that addr (of phy) should match either ext_phy0_addr
+	 * or ext_phy1_addr, or mdio commands won't be sent out.
+	 */
+	reg = readl(comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
+	reg &= ~MAC_EXT_PHY0_ADDR;
+	reg |= FIELD_PREP(MAC_EXT_PHY0_ADDR, addr);
+
+	reg2 = FIELD_PREP(MAC_CPU_PHY_WT_DATA, wdata) | FIELD_PREP(MAC_CPU_PHY_CMD, cmd) |
+	       FIELD_PREP(MAC_CPU_PHY_REG_ADDR, regnum) | FIELD_PREP(MAC_CPU_PHY_ADDR, addr);
+
+	/* Set ext_phy0_addr and then issue mdio command.
+	 * No interrupt is allowed in between.
+	 */
+	spin_lock_irq(&comm->mdio_lock);
+	writel(reg, comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
+	writel(reg2, comm->l2sw_reg_base + L2SW_PHY_CNTL_REG0);
+	spin_unlock_irq(&comm->mdio_lock);
+
+	ret = read_poll_timeout(readl, val, val & cmd, 1, 1000, true,
+				comm->l2sw_reg_base + L2SW_PHY_CNTL_REG1);
+
+	/* Set ext_phy0_addr back to 31 to prevent
+	 * from sending mdio command to phy by
+	 * hardware auto-mdio function.
+	 */
+	reg = readl(comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
+	reg &= ~MAC_EXT_PHY0_ADDR;
+	reg |= FIELD_PREP(MAC_EXT_PHY0_ADDR, 31);
+	writel(reg, comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
+
+	if (ret == 0)
+		return val >> 16;
+	else
+		return ret;
+}
+
+static int spl2sw_mii_read(struct mii_bus *bus, int addr, int regnum)
+{
+	struct spl2sw_common *comm = bus->priv;
+
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	return spl2sw_mdio_access(comm, SPL2SW_MDIO_READ_CMD, addr, regnum, 0);
+}
+
+static int spl2sw_mii_write(struct mii_bus *bus, int addr, int regnum, u16 val)
+{
+	struct spl2sw_common *comm = bus->priv;
+	int ret;
+
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	ret = spl2sw_mdio_access(comm, SPL2SW_MDIO_WRITE_CMD, addr, regnum, val);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+u32 spl2sw_mdio_init(struct spl2sw_common *comm)
+{
+	struct device_node *mdio_np;
+	struct mii_bus *mii_bus;
+	int ret;
+
+	/* Get mdio child node. */
+	mdio_np = of_get_child_by_name(comm->pdev->dev.of_node, "mdio");
+	if (!mdio_np) {
+		dev_err(&comm->pdev->dev, "No mdio child node found!\n");
+		return -ENODEV;
+	}
+
+	/* Allocate and register mdio bus. */
+	mii_bus = devm_mdiobus_alloc(&comm->pdev->dev);
+	if (!mii_bus) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	mii_bus->name = "sunplus_mii_bus";
+	mii_bus->parent = &comm->pdev->dev;
+	mii_bus->priv = comm;
+	mii_bus->read = spl2sw_mii_read;
+	mii_bus->write = spl2sw_mii_write;
+	snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&comm->pdev->dev));
+
+	ret = of_mdiobus_register(mii_bus, mdio_np);
+	if (ret) {
+		dev_err(&comm->pdev->dev, "Failed to register mdiobus!\n");
+		goto out;
+	}
+
+	comm->mii_bus = mii_bus;
+
+out:
+	of_node_put(mdio_np);
+	return ret;
+}
+
+void spl2sw_mdio_remove(struct spl2sw_common *comm)
+{
+	if (comm->mii_bus) {
+		mdiobus_unregister(comm->mii_bus);
+		comm->mii_bus = NULL;
+	}
+}