// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2021 NXP
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
#include <linux/module.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <dt-bindings/phy/phy-imx8-pcie.h>
#define IMX8MM_PCIE_PHY_CMN_REG061 0x184
#define ANA_PLL_CLK_OUT_TO_EXT_IO_EN BIT(0)
#define IMX8MM_PCIE_PHY_CMN_REG062 0x188
#define ANA_PLL_CLK_OUT_TO_EXT_IO_SEL BIT(3)
#define IMX8MM_PCIE_PHY_CMN_REG063 0x18C
#define AUX_PLL_REFCLK_SEL_SYS_PLL GENMASK(7, 6)
#define IMX8MM_PCIE_PHY_CMN_REG064 0x190
#define ANA_AUX_RX_TX_SEL_TX BIT(7)
#define ANA_AUX_RX_TERM_GND_EN BIT(3)
#define ANA_AUX_TX_TERM BIT(2)
#define IMX8MM_PCIE_PHY_CMN_REG065 0x194
#define ANA_AUX_RX_TERM (BIT(7) | BIT(4))
#define ANA_AUX_TX_LVL GENMASK(3, 0)
#define IMX8MM_PCIE_PHY_CMN_REG75 0x1D4
#define PCIE_PHY_CMN_REG75_PLL_DONE 0x3
#define PCIE_PHY_TRSV_REG5 0x414
#define PCIE_PHY_TRSV_REG5_GEN1_DEEMP 0x2D
#define PCIE_PHY_TRSV_REG6 0x418
#define PCIE_PHY_TRSV_REG6_GEN2_DEEMP 0xF
#define IMX8MM_GPR_PCIE_REF_CLK_SEL GENMASK(25, 24)
#define IMX8MM_GPR_PCIE_REF_CLK_PLL FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
#define IMX8MM_GPR_PCIE_REF_CLK_EXT FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x2)
#define IMX8MM_GPR_PCIE_AUX_EN BIT(19)
#define IMX8MM_GPR_PCIE_CMN_RST BIT(18)
#define IMX8MM_GPR_PCIE_POWER_OFF BIT(17)
#define IMX8MM_GPR_PCIE_SSC_EN BIT(16)
#define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE BIT(9)
struct imx8_pcie_phy {
void __iomem *base;
struct clk *clk;
struct phy *phy;
struct regmap *iomuxc_gpr;
struct reset_control *reset;
u32 refclk_pad_mode;
u32 tx_deemph_gen1;
u32 tx_deemph_gen2;
bool clkreq_unused;
};
static int imx8_pcie_phy_power_on(struct phy *phy)
{
int ret;
u32 val, pad_mode;
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
reset_control_assert(imx8_phy->reset);
pad_mode = imx8_phy->refclk_pad_mode;
/* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
imx8_phy->clkreq_unused ?
0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_AUX_EN,
IMX8MM_GPR_PCIE_AUX_EN);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_POWER_OFF, 0);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_SSC_EN, 0);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_REF_CLK_SEL,
pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
IMX8MM_GPR_PCIE_REF_CLK_EXT :
IMX8MM_GPR_PCIE_REF_CLK_PLL);
usleep_range(100, 200);
/* Do the PHY common block reset */
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_CMN_RST,
IMX8MM_GPR_PCIE_CMN_RST);
usleep_range(200, 500);
if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||
pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {
/* Configure the pad as input */
val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
} else {
/* Configure the PHY to output the refclock via pad */
writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
}
if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT ||
pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {
/* Source clock from SoC internal PLL */
writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
writel(val | ANA_AUX_RX_TERM_GND_EN,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
}
/* Tune PHY de-emphasis setting to pass PCIe compliance. */
if (imx8_phy->tx_deemph_gen1)
writel(imx8_phy->tx_deemph_gen1,
imx8_phy->base + PCIE_PHY_TRSV_REG5);
if (imx8_phy->tx_deemph_gen2)
writel(imx8_phy->tx_deemph_gen2,
imx8_phy->base + PCIE_PHY_TRSV_REG6);
reset_control_deassert(imx8_phy->reset);
/* Polling to check the phy is ready or not. */
ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG75,
val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
10, 20000);
return ret;
}
static int imx8_pcie_phy_init(struct phy *phy)
{
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
return clk_prepare_enable(imx8_phy->clk);
}
static int imx8_pcie_phy_exit(struct phy *phy)
{
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
clk_disable_unprepare(imx8_phy->clk);
return 0;
}
static const struct phy_ops imx8_pcie_phy_ops = {
.init = imx8_pcie_phy_init,
.exit = imx8_pcie_phy_exit,
.power_on = imx8_pcie_phy_power_on,
.owner = THIS_MODULE,
};
static int imx8_pcie_phy_probe(struct platform_device *pdev)
{
struct phy_provider *phy_provider;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct imx8_pcie_phy *imx8_phy;
struct resource *res;
imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
if (!imx8_phy)
return -ENOMEM;
/* get PHY refclk pad mode */
of_property_read_u32(np, "fsl,refclk-pad-mode",
&imx8_phy->refclk_pad_mode);
if (of_property_read_u32(np, "fsl,tx-deemph-gen1",
&imx8_phy->tx_deemph_gen1))
imx8_phy->tx_deemph_gen1 = 0;
if (of_property_read_u32(np, "fsl,tx-deemph-gen2",
&imx8_phy->tx_deemph_gen2))
imx8_phy->tx_deemph_gen2 = 0;
if (of_property_read_bool(np, "fsl,clkreq-unsupported"))
imx8_phy->clkreq_unused = true;
else
imx8_phy->clkreq_unused = false;
imx8_phy->clk = devm_clk_get(dev, "ref");
if (IS_ERR(imx8_phy->clk)) {
dev_err(dev, "failed to get imx pcie phy clock\n");
return PTR_ERR(imx8_phy->clk);
}
/* Grab GPR config register range */
imx8_phy->iomuxc_gpr =
syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
if (IS_ERR(imx8_phy->iomuxc_gpr)) {
dev_err(dev, "unable to find iomuxc registers\n");
return PTR_ERR(imx8_phy->iomuxc_gpr);
}
imx8_phy->reset = devm_reset_control_get_exclusive(dev, "pciephy");
if (IS_ERR(imx8_phy->reset)) {
dev_err(dev, "Failed to get PCIEPHY reset control\n");
return PTR_ERR(imx8_phy->reset);
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
imx8_phy->base = devm_ioremap_resource(dev, res);
if (IS_ERR(imx8_phy->base))
return PTR_ERR(imx8_phy->base);
imx8_phy->phy = devm_phy_create(dev, NULL, &imx8_pcie_phy_ops);
if (IS_ERR(imx8_phy->phy))
return PTR_ERR(imx8_phy->phy);
phy_set_drvdata(imx8_phy->phy, imx8_phy);
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 imx8_pcie_phy_of_match[] = {
{.compatible = "fsl,imx8mm-pcie-phy",},
{ },
};
MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
static struct platform_driver imx8_pcie_phy_driver = {
.probe = imx8_pcie_phy_probe,
.driver = {
.name = "imx8-pcie-phy",
.of_match_table = imx8_pcie_phy_of_match,
}
};
module_platform_driver(imx8_pcie_phy_driver);
MODULE_DESCRIPTION("FSL IMX8 PCIE PHY driver");
MODULE_LICENSE("GPL v2");
