cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

phy-rcar-gen3-pcie.c (3357B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Renesas R-Car Gen3 PCIe PHY driver
      4 *
      5 * Copyright (C) 2018 Cogent Embedded, Inc.
      6 */
      7
      8#include <linux/clk.h>
      9#include <linux/io.h>
     10#include <linux/module.h>
     11#include <linux/of.h>
     12#include <linux/phy/phy.h>
     13#include <linux/of_device.h>
     14#include <linux/platform_device.h>
     15#include <linux/spinlock.h>
     16
     17#define PHY_CTRL		0x4000		/* R8A77980 only */
     18
     19/* PHY control register (PHY_CTRL) */
     20#define PHY_CTRL_PHY_PWDN	BIT(2)
     21
     22struct rcar_gen3_phy {
     23	struct phy *phy;
     24	spinlock_t lock;
     25	void __iomem *base;
     26};
     27
     28static void rcar_gen3_phy_pcie_modify_reg(struct phy *p, unsigned int reg,
     29					  u32 clear, u32 set)
     30{
     31	struct rcar_gen3_phy *phy = phy_get_drvdata(p);
     32	void __iomem *base = phy->base;
     33	unsigned long flags;
     34	u32 value;
     35
     36	spin_lock_irqsave(&phy->lock, flags);
     37
     38	value = readl(base + reg);
     39	value &= ~clear;
     40	value |= set;
     41	writel(value, base + reg);
     42
     43	spin_unlock_irqrestore(&phy->lock, flags);
     44}
     45
     46static int r8a77980_phy_pcie_power_on(struct phy *p)
     47{
     48	/* Power on the PCIe PHY */
     49	rcar_gen3_phy_pcie_modify_reg(p, PHY_CTRL, PHY_CTRL_PHY_PWDN, 0);
     50
     51	return 0;
     52}
     53
     54static int r8a77980_phy_pcie_power_off(struct phy *p)
     55{
     56	/* Power off the PCIe PHY */
     57	rcar_gen3_phy_pcie_modify_reg(p, PHY_CTRL, 0, PHY_CTRL_PHY_PWDN);
     58
     59	return 0;
     60}
     61
     62static const struct phy_ops r8a77980_phy_pcie_ops = {
     63	.power_on	= r8a77980_phy_pcie_power_on,
     64	.power_off	= r8a77980_phy_pcie_power_off,
     65	.owner		= THIS_MODULE,
     66};
     67
     68static const struct of_device_id rcar_gen3_phy_pcie_match_table[] = {
     69	{ .compatible = "renesas,r8a77980-pcie-phy" },
     70	{ }
     71};
     72MODULE_DEVICE_TABLE(of, rcar_gen3_phy_pcie_match_table);
     73
     74static int rcar_gen3_phy_pcie_probe(struct platform_device *pdev)
     75{
     76	struct device *dev = &pdev->dev;
     77	struct phy_provider *provider;
     78	struct rcar_gen3_phy *phy;
     79	void __iomem *base;
     80	int error;
     81
     82	if (!dev->of_node) {
     83		dev_err(dev,
     84			"This driver must only be instantiated from the device tree\n");
     85		return -EINVAL;
     86	}
     87
     88	base = devm_platform_ioremap_resource(pdev, 0);
     89	if (IS_ERR(base))
     90		return PTR_ERR(base);
     91
     92	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
     93	if (!phy)
     94		return -ENOMEM;
     95
     96	spin_lock_init(&phy->lock);
     97
     98	phy->base = base;
     99
    100	/*
    101	 * devm_phy_create() will call pm_runtime_enable(&phy->dev);
    102	 * And then, phy-core will manage runtime PM for this device.
    103	 */
    104	pm_runtime_enable(dev);
    105
    106	phy->phy = devm_phy_create(dev, NULL, &r8a77980_phy_pcie_ops);
    107	if (IS_ERR(phy->phy)) {
    108		dev_err(dev, "Failed to create PCIe PHY\n");
    109		error = PTR_ERR(phy->phy);
    110		goto error;
    111	}
    112	phy_set_drvdata(phy->phy, phy);
    113
    114	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
    115	if (IS_ERR(provider)) {
    116		dev_err(dev, "Failed to register PHY provider\n");
    117		error = PTR_ERR(provider);
    118		goto error;
    119	}
    120
    121	return 0;
    122
    123error:
    124	pm_runtime_disable(dev);
    125
    126	return error;
    127}
    128
    129static int rcar_gen3_phy_pcie_remove(struct platform_device *pdev)
    130{
    131	pm_runtime_disable(&pdev->dev);
    132
    133	return 0;
    134};
    135
    136static struct platform_driver rcar_gen3_phy_driver = {
    137	.driver = {
    138		.name		= "phy_rcar_gen3_pcie",
    139		.of_match_table	= rcar_gen3_phy_pcie_match_table,
    140	},
    141	.probe	= rcar_gen3_phy_pcie_probe,
    142	.remove = rcar_gen3_phy_pcie_remove,
    143};
    144
    145module_platform_driver(rcar_gen3_phy_driver);
    146
    147MODULE_LICENSE("GPL v2");
    148MODULE_DESCRIPTION("Renesas R-Car Gen3 PCIe PHY");
    149MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");