Staging
v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: 6880fa6c56601bb8ed59df6c30fd390cc5f6dd8f authored by Linus Torvalds on 12 September 2021, 23:28:37 UTC
Linux 5.15-rc1
Linux 5.15-rc1
Tip revision: 6880fa6
phy-mt7621-pci.c
// SPDX-License-Identifier: GPL-2.0+
/*
* Mediatek MT7621 PCI PHY Driver
* Author: Sergio Paracuellos <sergio.paracuellos@gmail.com>
*/
#include <dt-bindings/phy/phy.h>
#include <linux/clk.h>
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/sys_soc.h>
#define RG_PE1_PIPE_REG 0x02c
#define RG_PE1_PIPE_RST BIT(12)
#define RG_PE1_PIPE_CMD_FRC BIT(4)
#define RG_P0_TO_P1_WIDTH 0x100
#define RG_PE1_H_LCDDS_REG 0x49c
#define RG_PE1_H_LCDDS_PCW GENMASK(30, 0)
#define RG_PE1_FRC_H_XTAL_REG 0x400
#define RG_PE1_FRC_H_XTAL_TYPE BIT(8)
#define RG_PE1_H_XTAL_TYPE GENMASK(10, 9)
#define RG_PE1_FRC_PHY_REG 0x000
#define RG_PE1_FRC_PHY_EN BIT(4)
#define RG_PE1_PHY_EN BIT(5)
#define RG_PE1_H_PLL_REG 0x490
#define RG_PE1_H_PLL_BC GENMASK(23, 22)
#define RG_PE1_H_PLL_BP GENMASK(21, 18)
#define RG_PE1_H_PLL_IR GENMASK(15, 12)
#define RG_PE1_H_PLL_IC GENMASK(11, 8)
#define RG_PE1_H_PLL_PREDIV GENMASK(7, 6)
#define RG_PE1_PLL_DIVEN GENMASK(3, 1)
#define RG_PE1_H_PLL_FBKSEL_REG 0x4bc
#define RG_PE1_H_PLL_FBKSEL GENMASK(5, 4)
#define RG_PE1_H_LCDDS_SSC_PRD_REG 0x4a4
#define RG_PE1_H_LCDDS_SSC_PRD GENMASK(15, 0)
#define RG_PE1_H_LCDDS_SSC_DELTA_REG 0x4a8
#define RG_PE1_H_LCDDS_SSC_DELTA GENMASK(11, 0)
#define RG_PE1_H_LCDDS_SSC_DELTA1 GENMASK(27, 16)
#define RG_PE1_LCDDS_CLK_PH_INV_REG 0x4a0
#define RG_PE1_LCDDS_CLK_PH_INV BIT(5)
#define RG_PE1_H_PLL_BR_REG 0x4ac
#define RG_PE1_H_PLL_BR GENMASK(18, 16)
#define RG_PE1_MSTCKDIV_REG 0x414
#define RG_PE1_MSTCKDIV GENMASK(7, 6)
#define RG_PE1_FRC_MSTCKDIV BIT(5)
#define MAX_PHYS 2
/**
* struct mt7621_pci_phy - Mt7621 Pcie PHY core
* @dev: pointer to device
* @regmap: kernel regmap pointer
* @phy: pointer to the kernel PHY device
* @sys_clk: pointer to the system XTAL clock
* @port_base: base register
* @has_dual_port: if the phy has dual ports.
* @bypass_pipe_rst: mark if 'mt7621_bypass_pipe_rst'
* needs to be executed. Depends on chip revision.
*/
struct mt7621_pci_phy {
struct device *dev;
struct regmap *regmap;
struct phy *phy;
struct clk *sys_clk;
void __iomem *port_base;
bool has_dual_port;
bool bypass_pipe_rst;
};
static inline void mt7621_phy_rmw(struct mt7621_pci_phy *phy,
u32 reg, u32 clr, u32 set)
{
u32 val;
/*
* We cannot use 'regmap_write_bits' here because internally
* 'set' is masked before is set to the value that will be
* written to the register. That way results in no reliable
* pci setup. Avoid to mask 'set' before set value to 'val'
* completely avoid the problem.
*/
regmap_read(phy->regmap, reg, &val);
val &= ~clr;
val |= set;
regmap_write(phy->regmap, reg, val);
}
static void mt7621_bypass_pipe_rst(struct mt7621_pci_phy *phy)
{
mt7621_phy_rmw(phy, RG_PE1_PIPE_REG, 0, RG_PE1_PIPE_RST);
mt7621_phy_rmw(phy, RG_PE1_PIPE_REG, 0, RG_PE1_PIPE_CMD_FRC);
if (phy->has_dual_port) {
mt7621_phy_rmw(phy, RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH,
0, RG_PE1_PIPE_RST);
mt7621_phy_rmw(phy, RG_PE1_PIPE_REG + RG_P0_TO_P1_WIDTH,
0, RG_PE1_PIPE_CMD_FRC);
}
}
static int mt7621_set_phy_for_ssc(struct mt7621_pci_phy *phy)
{
struct device *dev = phy->dev;
unsigned long clk_rate;
clk_rate = clk_get_rate(phy->sys_clk);
if (!clk_rate)
return -EINVAL;
/* Set PCIe Port PHY to disable SSC */
/* Debug Xtal Type */
mt7621_phy_rmw(phy, RG_PE1_FRC_H_XTAL_REG,
RG_PE1_FRC_H_XTAL_TYPE | RG_PE1_H_XTAL_TYPE,
RG_PE1_FRC_H_XTAL_TYPE |
FIELD_PREP(RG_PE1_H_XTAL_TYPE, 0x00));
/* disable port */
mt7621_phy_rmw(phy, RG_PE1_FRC_PHY_REG, RG_PE1_PHY_EN,
RG_PE1_FRC_PHY_EN);
if (phy->has_dual_port) {
mt7621_phy_rmw(phy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH,
RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN);
}
if (clk_rate == 40000000) { /* 40MHz Xtal */
/* Set Pre-divider ratio (for host mode) */
mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV,
FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x01));
dev_dbg(dev, "Xtal is 40MHz\n");
} else if (clk_rate == 25000000) { /* 25MHz Xal */
mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV,
FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x00));
/* Select feedback clock */
mt7621_phy_rmw(phy, RG_PE1_H_PLL_FBKSEL_REG,
RG_PE1_H_PLL_FBKSEL,
FIELD_PREP(RG_PE1_H_PLL_FBKSEL, 0x01));
/* DDS NCPO PCW (for host mode) */
mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_PRD_REG,
RG_PE1_H_LCDDS_SSC_PRD,
FIELD_PREP(RG_PE1_H_LCDDS_SSC_PRD, 0x00));
/* DDS SSC dither period control */
mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_PRD_REG,
RG_PE1_H_LCDDS_SSC_PRD,
FIELD_PREP(RG_PE1_H_LCDDS_SSC_PRD, 0x18d));
/* DDS SSC dither amplitude control */
mt7621_phy_rmw(phy, RG_PE1_H_LCDDS_SSC_DELTA_REG,
RG_PE1_H_LCDDS_SSC_DELTA |
RG_PE1_H_LCDDS_SSC_DELTA1,
FIELD_PREP(RG_PE1_H_LCDDS_SSC_DELTA, 0x4a) |
FIELD_PREP(RG_PE1_H_LCDDS_SSC_DELTA1, 0x4a));
dev_dbg(dev, "Xtal is 25MHz\n");
} else { /* 20MHz Xtal */
mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG, RG_PE1_H_PLL_PREDIV,
FIELD_PREP(RG_PE1_H_PLL_PREDIV, 0x00));
dev_dbg(dev, "Xtal is 20MHz\n");
}
/* DDS clock inversion */
mt7621_phy_rmw(phy, RG_PE1_LCDDS_CLK_PH_INV_REG,
RG_PE1_LCDDS_CLK_PH_INV, RG_PE1_LCDDS_CLK_PH_INV);
/* Set PLL bits */
mt7621_phy_rmw(phy, RG_PE1_H_PLL_REG,
RG_PE1_H_PLL_BC | RG_PE1_H_PLL_BP | RG_PE1_H_PLL_IR |
RG_PE1_H_PLL_IC | RG_PE1_PLL_DIVEN,
FIELD_PREP(RG_PE1_H_PLL_BC, 0x02) |
FIELD_PREP(RG_PE1_H_PLL_BP, 0x06) |
FIELD_PREP(RG_PE1_H_PLL_IR, 0x02) |
FIELD_PREP(RG_PE1_H_PLL_IC, 0x01) |
FIELD_PREP(RG_PE1_PLL_DIVEN, 0x02));
mt7621_phy_rmw(phy, RG_PE1_H_PLL_BR_REG, RG_PE1_H_PLL_BR,
FIELD_PREP(RG_PE1_H_PLL_BR, 0x00));
if (clk_rate == 40000000) { /* 40MHz Xtal */
/* set force mode enable of da_pe1_mstckdiv */
mt7621_phy_rmw(phy, RG_PE1_MSTCKDIV_REG,
RG_PE1_MSTCKDIV | RG_PE1_FRC_MSTCKDIV,
FIELD_PREP(RG_PE1_MSTCKDIV, 0x01) |
RG_PE1_FRC_MSTCKDIV);
}
return 0;
}
static int mt7621_pci_phy_init(struct phy *phy)
{
struct mt7621_pci_phy *mphy = phy_get_drvdata(phy);
if (mphy->bypass_pipe_rst)
mt7621_bypass_pipe_rst(mphy);
return mt7621_set_phy_for_ssc(mphy);
}
static int mt7621_pci_phy_power_on(struct phy *phy)
{
struct mt7621_pci_phy *mphy = phy_get_drvdata(phy);
/* Enable PHY and disable force mode */
mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG,
RG_PE1_FRC_PHY_EN, RG_PE1_PHY_EN);
if (mphy->has_dual_port) {
mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH,
RG_PE1_FRC_PHY_EN, RG_PE1_PHY_EN);
}
return 0;
}
static int mt7621_pci_phy_power_off(struct phy *phy)
{
struct mt7621_pci_phy *mphy = phy_get_drvdata(phy);
/* Disable PHY */
mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG,
RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN);
if (mphy->has_dual_port) {
mt7621_phy_rmw(mphy, RG_PE1_FRC_PHY_REG + RG_P0_TO_P1_WIDTH,
RG_PE1_PHY_EN, RG_PE1_FRC_PHY_EN);
}
return 0;
}
static int mt7621_pci_phy_exit(struct phy *phy)
{
return 0;
}
static const struct phy_ops mt7621_pci_phy_ops = {
.init = mt7621_pci_phy_init,
.exit = mt7621_pci_phy_exit,
.power_on = mt7621_pci_phy_power_on,
.power_off = mt7621_pci_phy_power_off,
.owner = THIS_MODULE,
};
static struct phy *mt7621_pcie_phy_of_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct mt7621_pci_phy *mt7621_phy = dev_get_drvdata(dev);
if (WARN_ON(args->args[0] >= MAX_PHYS))
return ERR_PTR(-ENODEV);
mt7621_phy->has_dual_port = args->args[0];
dev_dbg(dev, "PHY for 0x%px (dual port = %d)\n",
mt7621_phy->port_base, mt7621_phy->has_dual_port);
return mt7621_phy->phy;
}
static const struct soc_device_attribute mt7621_pci_quirks_match[] = {
{ .soc_id = "mt7621", .revision = "E2" }
};
static const struct regmap_config mt7621_pci_phy_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.max_register = 0x700,
};
static int mt7621_pci_phy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
const struct soc_device_attribute *attr;
struct phy_provider *provider;
struct mt7621_pci_phy *phy;
phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
if (!phy)
return -ENOMEM;
attr = soc_device_match(mt7621_pci_quirks_match);
if (attr)
phy->bypass_pipe_rst = true;
phy->dev = dev;
platform_set_drvdata(pdev, phy);
phy->port_base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(phy->port_base)) {
dev_err(dev, "failed to remap phy regs\n");
return PTR_ERR(phy->port_base);
}
phy->regmap = devm_regmap_init_mmio(phy->dev, phy->port_base,
&mt7621_pci_phy_regmap_config);
if (IS_ERR(phy->regmap))
return PTR_ERR(phy->regmap);
phy->phy = devm_phy_create(dev, dev->of_node, &mt7621_pci_phy_ops);
if (IS_ERR(phy->phy)) {
dev_err(dev, "failed to create phy\n");
return PTR_ERR(phy->phy);
}
phy->sys_clk = devm_clk_get(dev, NULL);
if (IS_ERR(phy->sys_clk)) {
dev_err(dev, "failed to get phy clock\n");
return PTR_ERR(phy->sys_clk);
}
phy_set_drvdata(phy->phy, phy);
provider = devm_of_phy_provider_register(dev, mt7621_pcie_phy_of_xlate);
return PTR_ERR_OR_ZERO(provider);
}
static const struct of_device_id mt7621_pci_phy_ids[] = {
{ .compatible = "mediatek,mt7621-pci-phy" },
{},
};
MODULE_DEVICE_TABLE(of, mt7621_pci_phy_ids);
static struct platform_driver mt7621_pci_phy_driver = {
.probe = mt7621_pci_phy_probe,
.driver = {
.name = "mt7621-pci-phy",
.of_match_table = mt7621_pci_phy_ids,
},
};
builtin_platform_driver(mt7621_pci_phy_driver);
MODULE_AUTHOR("Sergio Paracuellos <sergio.paracuellos@gmail.com>");
MODULE_DESCRIPTION("MediaTek MT7621 PCIe PHY driver");
MODULE_LICENSE("GPL v2");