bmips: backport bcm6368-mdio-mux support

This patch has been accepted for linux v5.13.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 237 insertions, 0 deletions

diff --git a/target/linux/bmips/patches-5.10/047-v5.13-net-mdio-Add-BCM6368-MDIO-mux-bus-controller.patch b/target/linux/bmips/patches-5.10/047-v5.13-net-mdio-Add-BCM6368-MDIO-mux-bus-controller.patch
new file mode 100644
index 0000000000..0f1a2cd9ca
--- /dev/null
+++ b/target/linux/bmips/patches-5.10/047-v5.13-net-mdio-Add-BCM6368-MDIO-mux-bus-controller.patch
@@ -0,0 +1,237 @@
+From e239756717b5c866958823a1609e2ccf268435be Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Mon, 15 Mar 2021 16:45:28 +0100
+Subject: [PATCH 2/2] net: mdio: Add BCM6368 MDIO mux bus controller
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This controller is present on BCM6318, BCM6328, BCM6362, BCM6368 and BCM63268
+SoCs.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/mdio/Kconfig            |  11 ++
+ drivers/net/mdio/Makefile           |   1 +
+ drivers/net/mdio/mdio-mux-bcm6368.c | 184 ++++++++++++++++++++++++++++
+ 3 files changed, 196 insertions(+)
+ create mode 100644 drivers/net/mdio/mdio-mux-bcm6368.c
+
+--- 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)
+--- a/drivers/net/mdio/Makefile
++++ b/drivers/net/mdio/Makefile
+@@ -22,6 +22,7 @@ obj-$(CONFIG_MDIO_THUNDER)		+= mdio-thun
+ obj-$(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
+--- /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@gmail.com>
++ */
++
++#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@gmail.com>");
++MODULE_DESCRIPTION("BCM6368 mdiomux bus controller driver");
++MODULE_LICENSE("GPL v2");