From d3feb406733544dbf0e239ef945a09decdceac88 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= Date: Thu, 14 Apr 2016 11:37:43 +0200 Subject: [PATCH] phy: bcm-ns-usb2: new driver for USB 2.0 PHY on Northstar MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Northstar is a family of SoCs used in home routers. They have USB 2.0 and 3.0 controllers with PHYs that need to be properly initialized. This driver provides PHY init support in a generic way and can be bound with an EHCI controller driver. There are (just a few) registers being defined in bcma header. It's because DMU/CRU registers will be also needed in other drivers. We will need them e.g. in PCIe controller/PHY driver and at some point probably in clock driver for BCM53573 chipset. By using include/linux/bcma/ we avoid code duplication. Signed-off-by: Rafał Miłecki Signed-off-by: Kishon Vijay Abraham I --- .../devicetree/bindings/phy/bcm-ns-usb2-phy.txt | 21 ++++ drivers/phy/Kconfig | 9 ++ drivers/phy/Makefile | 1 + drivers/phy/phy-bcm-ns-usb2.c | 137 +++++++++++++++++++++ include/linux/bcma/bcma.h | 1 + include/linux/bcma/bcma_driver_arm_c9.h | 15 +++ 6 files changed, 184 insertions(+) create mode 100644 Documentation/devicetree/bindings/phy/bcm-ns-usb2-phy.txt create mode 100644 drivers/phy/phy-bcm-ns-usb2.c create mode 100644 include/linux/bcma/bcma_driver_arm_c9.h --- /dev/null +++ b/Documentation/devicetree/bindings/phy/bcm-ns-usb2-phy.txt @@ -0,0 +1,21 @@ +Driver for Broadcom Northstar USB 2.0 PHY + +Required properties: +- compatible: brcm,ns-usb2-phy +- reg: iomem address range of DMU (Device Management Unit) +- reg-names: "dmu", the only needed & supported reg right now +- clocks: USB PHY reference clock +- clock-names: "phy-ref-clk", the only needed & supported clock right now + +To initialize USB 2.0 PHY driver needs to setup PLL correctly. To do this it +requires passing phandle to the USB PHY reference clock. + +Example: + usb2-phy { + compatible = "brcm,ns-usb2-phy"; + reg = <0x1800c000 0x1000>; + reg-names = "dmu"; + #phy-cells = <0>; + clocks = <&genpll BCM_NSP_GENPLL_USB_PHY_REF_CLK>; + clock-names = "phy-ref-clk"; + }; --- a/drivers/phy/Kconfig +++ b/drivers/phy/Kconfig @@ -15,6 +15,15 @@ config GENERIC_PHY phy users can obtain reference to the PHY. All the users of this framework should select this config. +config PHY_BCM_NS_USB2 + tristate "Broadcom Northstar USB 2.0 PHY Driver" + depends on ARCH_BCM_IPROC || COMPILE_TEST + depends on HAS_IOMEM && OF + select GENERIC_PHY + help + Enable this to support Broadcom USB 2.0 PHY connected to the USB + controller on Northstar family. + config PHY_BERLIN_USB tristate "Marvell Berlin USB PHY Driver" depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF --- a/drivers/phy/Makefile +++ b/drivers/phy/Makefile @@ -3,6 +3,7 @@ # obj-$(CONFIG_GENERIC_PHY) += phy-core.o +obj-$(CONFIG_PHY_BCM_NS_USB2) += phy-bcm-ns-usb2.o obj-$(CONFIG_PHY_BERLIN_USB) += phy-berlin-usb.o obj-$(CONFIG_PHY_BERLIN_SATA) += phy-berlin-sata.o obj-$(CONFIG_PHY_DM816X_USB) += phy-dm816x-usb.o --- /dev/null +++ b/drivers/phy/phy-bcm-ns-usb2.c @@ -0,0 +1,137 @@ +/* + * Broadcom Northstar USB 2.0 PHY Driver + * + * Copyright (C) 2016 Rafał Miłecki + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct bcm_ns_usb2 { + struct device *dev; + struct clk *ref_clk; + struct phy *phy; + void __iomem *dmu; +}; + +static int bcm_ns_usb2_phy_init(struct phy *phy) +{ + struct bcm_ns_usb2 *usb2 = phy_get_drvdata(phy); + struct device *dev = usb2->dev; + void __iomem *dmu = usb2->dmu; + u32 ref_clk_rate, usb2ctl, usb_pll_ndiv, usb_pll_pdiv; + int err = 0; + + err = clk_prepare_enable(usb2->ref_clk); + if (err < 0) { + dev_err(dev, "Failed to prepare ref clock: %d\n", err); + goto err_out; + } + + ref_clk_rate = clk_get_rate(usb2->ref_clk); + if (!ref_clk_rate) { + dev_err(dev, "Failed to get ref clock rate\n"); + err = -EINVAL; + goto err_clk_off; + } + + usb2ctl = readl(dmu + BCMA_DMU_CRU_USB2_CONTROL); + + if (usb2ctl & BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK) { + usb_pll_pdiv = usb2ctl; + usb_pll_pdiv &= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK; + usb_pll_pdiv >>= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_SHIFT; + } else { + usb_pll_pdiv = 1 << 3; + } + + /* Calculate ndiv based on a solid 1920 MHz that is for USB2 PHY */ + usb_pll_ndiv = (1920000000 * usb_pll_pdiv) / ref_clk_rate; + + /* Unlock DMU PLL settings with some magic value */ + writel(0x0000ea68, dmu + BCMA_DMU_CRU_CLKSET_KEY); + + /* Write USB 2.0 PLL control setting */ + usb2ctl &= ~BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_MASK; + usb2ctl |= usb_pll_ndiv << BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_SHIFT; + writel(usb2ctl, dmu + BCMA_DMU_CRU_USB2_CONTROL); + + /* Lock DMU PLL settings */ + writel(0x00000000, dmu + BCMA_DMU_CRU_CLKSET_KEY); + +err_clk_off: + clk_disable_unprepare(usb2->ref_clk); +err_out: + return err; +} + +static const struct phy_ops ops = { + .init = bcm_ns_usb2_phy_init, + .owner = THIS_MODULE, +}; + +static int bcm_ns_usb2_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct bcm_ns_usb2 *usb2; + struct resource *res; + struct phy_provider *phy_provider; + + usb2 = devm_kzalloc(&pdev->dev, sizeof(*usb2), GFP_KERNEL); + if (!usb2) + return -ENOMEM; + usb2->dev = dev; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dmu"); + usb2->dmu = devm_ioremap_resource(dev, res); + if (IS_ERR(usb2->dmu)) { + dev_err(dev, "Failed to map DMU regs\n"); + return PTR_ERR(usb2->dmu); + } + + usb2->ref_clk = devm_clk_get(dev, "phy-ref-clk"); + if (IS_ERR(usb2->ref_clk)) { + dev_err(dev, "Clock not defined\n"); + return PTR_ERR(usb2->ref_clk); + } + + usb2->phy = devm_phy_create(dev, NULL, &ops); + if (IS_ERR(dev)) + return PTR_ERR(dev); + + phy_set_drvdata(usb2->phy, usb2); + platform_set_drvdata(pdev, usb2); + + phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); + return PTR_ERR_OR_ZERO(phy_provider); +} + +static const struct of_device_id bcm_ns_usb2_id_table[] = { + { .compatible = "brcm,ns-usb2-phy", }, + {}, +}; +MODULE_DEVICE_TABLE(of, bcm_ns_usb2_id_table); + +static struct platform_driver bcm_ns_usb2_driver = { + .probe = bcm_ns_usb2_probe, + .driver = { + .name = "bcm_ns_usb2", + .of_match_table = bcm_ns_usb2_id_table, + }, +}; +module_platform_driver(bcm_ns_usb2_driver); + +MODULE_LICENSE("GPL v2"); --- a/include/linux/bcma/bcma.h +++ b/include/linux/bcma/bcma.h @@ -4,6 +4,7 @@ #include #include +#include #include #include #include --- /dev/null +++ b/include/linux/bcma/bcma_driver_arm_c9.h @@ -0,0 +1,15 @@ +#ifndef LINUX_BCMA_DRIVER_ARM_C9_H_ +#define LINUX_BCMA_DRIVER_ARM_C9_H_ + +/* DMU (Device Management Unit) */ +#define BCMA_DMU_CRU_USB2_CONTROL 0x0164 +#define BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_MASK 0x00000FFC +#define BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_SHIFT 2 +#define BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK 0x00007000 +#define BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_SHIFT 12 +#define BCMA_DMU_CRU_CLKSET_KEY 0x0180 +#define BCMA_DMU_CRU_STRAPS_CTRL 0x02A0 +#define BCMA_DMU_CRU_STRAPS_CTRL_USB3 0x00000010 +#define BCMA_DMU_CRU_STRAPS_CTRL_4BYTE 0x00008000 + +#endif /* LINUX_BCMA_DRIVER_ARM_C9_H_ */