Re: [PATCH 1/2] net: mdio: add ipq8064 mdio driver
From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Date: 2020-02-20 15:27:44
Also in:
linux-arm-msm, linux-devicetree, lkml
On Thu, Feb 20, 2020 at 04:12:55PM +0100, Ansuel Smith wrote:
quoted hunk ↗ jump to hunk
Currently ipq806x soc use generi bitbang driver to comunicate with the gmac ethernet interface. Add a dedicated driver created by chunkeey to fix this. Christian Lamparter [off-list ref] Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> --- drivers/net/phy/Kconfig | 8 ++ drivers/net/phy/Makefile | 1 + drivers/net/phy/mdio-ipq8064.c | 163 +++++++++++++++++++++++++++++++++ 3 files changed, 172 insertions(+) create mode 100644 drivers/net/phy/mdio-ipq8064.cdiff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig index 9dabe03a668c..ec2a5493a7e8 100644 --- a/drivers/net/phy/Kconfig +++ b/drivers/net/phy/Kconfig@@ -157,6 +157,14 @@ config MDIO_I2C This is library mode. +config MDIO_IPQ8064 + tristate "Qualcomm IPQ8064 MDIO interface support" + depends on HAS_IOMEM && OF_MDIO + depends on MFD_SYSCON + help + This driver supports the MDIO interface found in the network + interface units of the IPQ8064 SoC + config MDIO_MOXART tristate "MOXA ART MDIO interface support" depends on ARCH_MOXART || COMPILE_TESTdiff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile index fe5badf13b65..8f02bd2089f3 100644 --- a/drivers/net/phy/Makefile +++ b/drivers/net/phy/Makefile@@ -36,6 +36,7 @@ obj-$(CONFIG_MDIO_CAVIUM) += mdio-cavium.o obj-$(CONFIG_MDIO_GPIO) += mdio-gpio.o obj-$(CONFIG_MDIO_HISI_FEMAC) += mdio-hisi-femac.o obj-$(CONFIG_MDIO_I2C) += mdio-i2c.o +obj-$(CONFIG_MDIO_IPQ8064) += mdio-ipq8064.o obj-$(CONFIG_MDIO_MOXART) += mdio-moxart.o obj-$(CONFIG_MDIO_MSCC_MIIM) += mdio-mscc-miim.o obj-$(CONFIG_MDIO_OCTEON) += mdio-octeon.odiff --git a/drivers/net/phy/mdio-ipq8064.c b/drivers/net/phy/mdio-ipq8064.c new file mode 100644 index 000000000000..c76e6a647787 --- /dev/null +++ b/drivers/net/phy/mdio-ipq8064.c@@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Qualcomm IPQ8064 MDIO interface driver +// +// Copyright (C) 2019 Christian Lamparter <chunkeey@gmail.com> + +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/of_mdio.h> +#include <linux/phy.h> +#include <linux/platform_device.h> +#include <linux/mfd/syscon.h> + +/* MII address register definitions */ +#define MII_ADDR_REG_ADDR 0x10 +#define MII_BUSY BIT(0) +#define MII_WRITE BIT(1) +#define MII_CLKRANGE_60_100M (0 << 2) +#define MII_CLKRANGE_100_150M (1 << 2) +#define MII_CLKRANGE_20_35M (2 << 2) +#define MII_CLKRANGE_35_60M (3 << 2) +#define MII_CLKRANGE_150_250M (4 << 2) +#define MII_CLKRANGE_250_300M (5 << 2) +#define MII_CLKRANGE_MASK GENMASK(4, 2) +#define MII_REG_SHIFT 6 +#define MII_REG_MASK GENMASK(10, 6) +#define MII_ADDR_SHIFT 11 +#define MII_ADDR_MASK GENMASK(15, 11) + +#define MII_DATA_REG_ADDR 0x14 + +#define MII_MDIO_DELAY (1000) +#define MII_MDIO_RETRY (10) + +struct ipq8064_mdio { + struct regmap *base; /* NSS_GMAC0_BASE */ +}; + +static int +ipq8064_mdio_wait_busy(struct ipq8064_mdio *priv) +{ + int i; + + for (i = 0; i < MII_MDIO_RETRY; i++) { + unsigned int busy; + + regmap_read(priv->base, MII_ADDR_REG_ADDR, &busy); + if (!(busy & MII_BUSY)) + return 0; + + udelay(MII_MDIO_DELAY); + }
On the last loop, this will delay MII_MDIO_DELAY and then return -ETIMEDOUT, which is not nice behaviour. Have you considered using regmap_read_poll_timeout() here?
+
+ return -ETIMEDOUT;
+}
+
+static int
+ipq8064_mdio_read(struct mii_bus *bus, int phy_addr, int reg_offset)
+{
+ struct ipq8064_mdio *priv = bus->priv;
+ u32 miiaddr = MII_BUSY | MII_CLKRANGE_250_300M;
+ u32 ret_val;
+ int err;
+
+ miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
+ ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);This looks like it only supports Clause 22 accesses, so shouldn't it reject Clause 45 accesses (signified by reg_offset & MII_ADDR_C45) ?
+ regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
+ usleep_range(10, 20);
+
+ err = ipq8064_mdio_wait_busy(priv);
+ if (err)
+ return err;
+
+ regmap_read(priv->base, MII_DATA_REG_ADDR, &ret_val);
+ return (int)ret_val;
+}
+
+static int
+ipq8064_mdio_write(struct mii_bus *bus, int phy_addr, int reg_offset, u16 data)
+{
+ struct ipq8064_mdio *priv = bus->priv;
+ u32 miiaddr = MII_WRITE | MII_BUSY | MII_CLKRANGE_250_300M;
+
+ regmap_write(priv->base, MII_DATA_REG_ADDR, data);
+
+ miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
+ ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);Same here as for ipq8064_mdio_read().
+
+ regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
+ usleep_range(10, 20);
+
+ return ipq8064_mdio_wait_busy(priv);
+}
+
+static int
+ipq8064_mdio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct ipq8064_mdio *priv;
+ struct mii_bus *bus;
+ int ret;
+
+ bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
+ if (!bus)
+ return -ENOMEM;
+
+ bus->name = "ipq8064_mdio_bus";
+ bus->read = ipq8064_mdio_read;
+ bus->write = ipq8064_mdio_write;
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+ bus->parent = &pdev->dev;
+
+ priv = bus->priv;
+ priv->base = syscon_node_to_regmap(np);
+ if (IS_ERR_OR_NULL(priv->base)) {
+ priv->base = syscon_regmap_lookup_by_phandle(np, "master");
+ if (IS_ERR_OR_NULL(priv->base)) {
+ pr_err("master phandle not found\n");
+ return -EINVAL;
+ }
+ }Does syscon_node_to_regmap() return NULL? From what I can see in drivers/mfd/syscon.c, both that and syscon_regmap_lookup_by_phandle() returns an error pointer, and if there's an error code, it should be propagated. Using dev_err(&pdev->dev, ...) for that error print is also nice - imagine a kernel log where you have a line appear that only says "master phandle not found" - you don't know where in the kernel it came from, or even what device it's referring to.
+
+ ret = of_mdiobus_register(bus, np);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, bus);
+ return 0;
+}
+
+static int
+ipq8064_mdio_remove(struct platform_device *pdev)
+{
+ struct mii_bus *bus = platform_get_drvdata(pdev);
+
+ mdiobus_unregister(bus);
+
+ return 0;
+}
+
+static const struct of_device_id ipq8064_mdio_dt_ids[] = {
+ { .compatible = "qcom,ipq8064-mdio" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ipq8064_mdio_dt_ids);
+
+static struct platform_driver ipq8064_mdio_driver = {
+ .probe = ipq8064_mdio_probe,
+ .remove = ipq8064_mdio_remove,
+ .driver = {
+ .name = "ipq8064-mdio",
+ .of_match_table = ipq8064_mdio_dt_ids,
+ },
+};
+
+module_platform_driver(ipq8064_mdio_driver);
+
+MODULE_DESCRIPTION("Qualcomm IPQ8064 MDIO interface driver");
+MODULE_AUTHOR("Christian Lamparter [off-list ref]");
+MODULE_LICENSE("GPL");
--
2.25.0
-- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up