This controller is present on BCM6318, BCM6328, BCM6362, BCM6368 and BCM63268
SoCs.
Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
---
v2: add missing module author, description and license.
drivers/net/mdio/Kconfig | 11 ++
drivers/net/mdio/Makefile | 1 +
drivers/net/mdio/mdio-mux-bcm6368.c | 183 ++++++++++++++++++++++++++++
3 files changed, 195 insertions(+)
create mode 100644 drivers/net/mdio/mdio-mux-bcm6368.c
diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig
index a10cc460d7cf..d06e06f5e31a 100644
--- a/drivers/net/mdio/Kconfig
+++ b/drivers/net/mdio/Kconfig
@@ -200,6 +200,17 @@ config MDIO_BUS_MUX_MESON_G12A
the amlogic g12a SoC. The multiplexers connects either the external
or the internal MDIO bus to the parent bus.
+config MDIO_BUS_MUX_BCM6368
+ tristate "Broadcom BCM6368 MDIO bus multiplexers"
+ depends on OF && OF_MDIO && (BMIPS_GENERIC || COMPILE_TEST)
+ select MDIO_BUS_MUX
+ default BMIPS_GENERIC
+ help
+ This module provides a driver for MDIO bus multiplexers found in
+ BCM6368 based Broadcom SoCs. This multiplexer connects one of several
+ child MDIO bus to a parent bus. Buses could be internal as well as
+ external and selection logic lies inside the same multiplexer.
+
config MDIO_BUS_MUX_BCM_IPROC
tristate "Broadcom iProc based MDIO bus multiplexers"
depends on OF && OF_MDIO && (ARCH_BCM_IPROC || COMPILE_TEST)
diff --git a/drivers/net/mdio/Makefile b/drivers/net/mdio/Makefile
index 5c498dde463f..c3ec0ef989df 100644
--- a/drivers/net/mdio/Makefile
+++ b/drivers/net/mdio/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_MDIO_THUNDER) += mdio-thunder.o
obj-$(CONFIG_MDIO_XGENE) += mdio-xgene.o
obj-$(CONFIG_MDIO_BUS_MUX) += mdio-mux.o
+obj-$(CONFIG_MDIO_BUS_MUX_BCM6368) += mdio-mux-bcm6368.o
obj-$(CONFIG_MDIO_BUS_MUX_BCM_IPROC) += mdio-mux-bcm-iproc.o
obj-$(CONFIG_MDIO_BUS_MUX_GPIO) += mdio-mux-gpio.o
obj-$(CONFIG_MDIO_BUS_MUX_MESON_G12A) += mdio-mux-meson-g12a.o
diff --git a/drivers/net/mdio/mdio-mux-bcm6368.c b/drivers/net/mdio/mdio-mux-bcm6368.c
new file mode 100644
index 000000000000..0abd83a9124f
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-bcm6368.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Broadcom BCM6368 mdiomux bus controller driver
+ *
+ * Copyright (C) 2021 Álvaro Fernández Rojas <noltari@xxxxxxxxx>
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mdio-mux.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+
+#define MDIOC_REG 0x0
+#define MDIOC_EXT_MASK BIT(16)
+#define MDIOC_REG_SHIFT 20
+#define MDIOC_PHYID_SHIFT 25
+#define MDIOC_RD_MASK BIT(30)
+#define MDIOC_WR_MASK BIT(31)
+
+#define MDIOD_REG 0x4
+
+struct bcm6368_mdiomux_desc {
+ void *mux_handle;
+ void __iomem *base;
+ struct device *dev;
+ struct mii_bus *mii_bus;
+ int ext_phy;
+};
+
+static int bcm6368_mdiomux_read(struct mii_bus *bus, int phy_id, int loc)
+{
+ struct bcm6368_mdiomux_desc *md = bus->priv;
+ uint32_t reg;
+ int ret;
+
+ __raw_writel(0, md->base + MDIOC_REG);
+
+ reg = MDIOC_RD_MASK |
+ (phy_id << MDIOC_PHYID_SHIFT) |
+ (loc << MDIOC_REG_SHIFT);
+ if (md->ext_phy)
+ reg |= MDIOC_EXT_MASK;
+
+ __raw_writel(reg, md->base + MDIOC_REG);
+ udelay(50);
+ ret = __raw_readw(md->base + MDIOD_REG);
+
+ return ret;
+}
+
+static int bcm6368_mdiomux_write(struct mii_bus *bus, int phy_id, int loc,
+ uint16_t val)
+{
+ struct bcm6368_mdiomux_desc *md = bus->priv;
+ uint32_t reg;
+
+ __raw_writel(0, md->base + MDIOC_REG);
+
+ reg = MDIOC_WR_MASK |
+ (phy_id << MDIOC_PHYID_SHIFT) |
+ (loc << MDIOC_REG_SHIFT);
+ if (md->ext_phy)
+ reg |= MDIOC_EXT_MASK;
+ reg |= val;
+
+ __raw_writel(reg, md->base + MDIOC_REG);
+ udelay(50);
+
+ return 0;
+}
+
+static int bcm6368_mdiomux_switch_fn(int current_child, int desired_child,
+ void *data)
+{
+ struct bcm6368_mdiomux_desc *md = data;
+
+ md->ext_phy = desired_child;
+
+ return 0;
+}
+
+static int bcm6368_mdiomux_probe(struct platform_device *pdev)
+{
+ struct bcm6368_mdiomux_desc *md;
+ struct mii_bus *bus;
+ struct resource *res;
+ int rc;
+
+ md = devm_kzalloc(&pdev->dev, sizeof(*md), GFP_KERNEL);
+ if (!md)
+ return -ENOMEM;
+ md->dev = &pdev->dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ /*
+ * Just ioremap, as this MDIO block is usually integrated into an
+ * Ethernet MAC controller register range
+ */
+ md->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+ if (!md->base) {
+ dev_err(&pdev->dev, "failed to ioremap register\n");
+ return -ENOMEM;
+ }
+
+ md->mii_bus = devm_mdiobus_alloc(&pdev->dev);
+ if (!md->mii_bus) {
+ dev_err(&pdev->dev, "mdiomux bus alloc failed\n");
+ return ENOMEM;
+ }
+
+ bus = md->mii_bus;
+ bus->priv = md;
+ bus->name = "BCM6368 MDIO mux bus";
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
+ bus->parent = &pdev->dev;
+ bus->read = bcm6368_mdiomux_read;
+ bus->write = bcm6368_mdiomux_write;
+ bus->phy_mask = 0x3f;
+ bus->dev.of_node = pdev->dev.of_node;
+
+ rc = mdiobus_register(bus);
+ if (rc) {
+ dev_err(&pdev->dev, "mdiomux registration failed\n");
+ return rc;
+ }
+
+ platform_set_drvdata(pdev, md);
+
+ rc = mdio_mux_init(md->dev, md->dev->of_node,
+ bcm6368_mdiomux_switch_fn, &md->mux_handle, md,
+ md->mii_bus);
+ if (rc) {
+ dev_info(md->dev, "mdiomux initialization failed\n");
+ goto out_register;
+ }
+
+ dev_info(&pdev->dev, "Broadcom BCM6368 MDIO mux bus\n");
+
+ return 0;
+
+out_register:
+ mdiobus_unregister(bus);
+ return rc;
+}
+
+static int bcm6368_mdiomux_remove(struct platform_device *pdev)
+{
+ struct bcm6368_mdiomux_desc *md = platform_get_drvdata(pdev);
+
+ mdio_mux_uninit(md->mux_handle);
+ mdiobus_unregister(md->mii_bus);
+
+ return 0;
+}
+
+static const struct of_device_id bcm6368_mdiomux_ids[] = {
+ { .compatible = "brcm,bcm6368-mdio-mux", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, bcm6368_mdiomux_ids);
+
+static struct platform_driver bcm6368_mdiomux_driver = {
+ .driver = {
+ .name = "bcm6368-mdio-mux",
+ .of_match_table = bcm6368_mdiomux_ids,
+ },
+ .probe = bcm6368_mdiomux_probe,
+ .remove = bcm6368_mdiomux_remove,
+};
+module_platform_driver(bcm6368_mdiomux_driver);
+
+MODULE_AUTHOR("Álvaro Fernández Rojas <noltari@xxxxxxxxx>");
+MODULE_DESCRIPTION("BCM6368 mdiomux bus controller driver");
+MODULE_LICENSE("GPL v2");
--
2.20.1
