root/drivers/phy/marvell/phy-mmp3-usb.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2011 Marvell International Ltd. All rights reserved.
 * Copyright (C) 2018,2019 Lubomir Rintel <lkundrak@v3.sk>
 */

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/soc/mmp/cputype.h>

#define USB2_PLL_REG0           0x4
#define USB2_PLL_REG1           0x8
#define USB2_TX_REG0            0x10
#define USB2_TX_REG1            0x14
#define USB2_TX_REG2            0x18
#define USB2_RX_REG0            0x20
#define USB2_RX_REG1            0x24
#define USB2_RX_REG2            0x28
#define USB2_ANA_REG0           0x30
#define USB2_ANA_REG1           0x34
#define USB2_ANA_REG2           0x38
#define USB2_DIG_REG0           0x3C
#define USB2_DIG_REG1           0x40
#define USB2_DIG_REG2           0x44
#define USB2_DIG_REG3           0x48
#define USB2_TEST_REG0          0x4C
#define USB2_TEST_REG1          0x50
#define USB2_TEST_REG2          0x54
#define USB2_CHARGER_REG0       0x58
#define USB2_OTG_REG0           0x5C
#define USB2_PHY_MON0           0x60
#define USB2_RESETVE_REG0       0x64
#define USB2_ICID_REG0          0x78
#define USB2_ICID_REG1          0x7C

/* USB2_PLL_REG0 */

/* This is for Ax stepping */
#define USB2_PLL_FBDIV_SHIFT_MMP3               0
#define USB2_PLL_FBDIV_MASK_MMP3                (0xFF << 0)

#define USB2_PLL_REFDIV_SHIFT_MMP3              8
#define USB2_PLL_REFDIV_MASK_MMP3               (0xF << 8)

#define USB2_PLL_VDD12_SHIFT_MMP3               12
#define USB2_PLL_VDD18_SHIFT_MMP3               14

/* This is for B0 stepping */
#define USB2_PLL_FBDIV_SHIFT_MMP3_B0            0
#define USB2_PLL_REFDIV_SHIFT_MMP3_B0           9
#define USB2_PLL_VDD18_SHIFT_MMP3_B0            14
#define USB2_PLL_FBDIV_MASK_MMP3_B0             0x01FF
#define USB2_PLL_REFDIV_MASK_MMP3_B0            0x3E00

#define USB2_PLL_CAL12_SHIFT_MMP3               0
#define USB2_PLL_CALI12_MASK_MMP3               (0x3 << 0)

#define USB2_PLL_VCOCAL_START_SHIFT_MMP3        2

#define USB2_PLL_KVCO_SHIFT_MMP3                4
#define USB2_PLL_KVCO_MASK_MMP3                 (0x7<<4)

#define USB2_PLL_ICP_SHIFT_MMP3                 8
#define USB2_PLL_ICP_MASK_MMP3                  (0x7<<8)

#define USB2_PLL_LOCK_BYPASS_SHIFT_MMP3         12

#define USB2_PLL_PU_PLL_SHIFT_MMP3              13
#define USB2_PLL_PU_PLL_MASK                    (0x1 << 13)

#define USB2_PLL_READY_MASK_MMP3                (0x1 << 15)

/* USB2_TX_REG0 */
#define USB2_TX_IMPCAL_VTH_SHIFT_MMP3           8
#define USB2_TX_IMPCAL_VTH_MASK_MMP3            (0x7 << 8)

#define USB2_TX_RCAL_START_SHIFT_MMP3           13

/* USB2_TX_REG1 */
#define USB2_TX_CK60_PHSEL_SHIFT_MMP3           0
#define USB2_TX_CK60_PHSEL_MASK_MMP3            (0xf << 0)

#define USB2_TX_AMP_SHIFT_MMP3                  4
#define USB2_TX_AMP_MASK_MMP3                   (0x7 << 4)

#define USB2_TX_VDD12_SHIFT_MMP3                8
#define USB2_TX_VDD12_MASK_MMP3                 (0x3 << 8)

/* USB2_TX_REG2 */
#define USB2_TX_DRV_SLEWRATE_SHIFT              10

/* USB2_RX_REG0 */
#define USB2_RX_SQ_THRESH_SHIFT_MMP3            4
#define USB2_RX_SQ_THRESH_MASK_MMP3             (0xf << 4)

#define USB2_RX_SQ_LENGTH_SHIFT_MMP3            10
#define USB2_RX_SQ_LENGTH_MASK_MMP3             (0x3 << 10)

/* USB2_ANA_REG1*/
#define USB2_ANA_PU_ANA_SHIFT_MMP3              14

/* USB2_OTG_REG0 */
#define USB2_OTG_PU_OTG_SHIFT_MMP3              3

struct mmp3_usb_phy {
        struct phy *phy;
        void __iomem *base;
};

static unsigned int u2o_get(void __iomem *base, unsigned int offset)
{
        return readl_relaxed(base + offset);
}

static void u2o_set(void __iomem *base, unsigned int offset,
                unsigned int value)
{
        u32 reg;

        reg = readl_relaxed(base + offset);
        reg |= value;
        writel_relaxed(reg, base + offset);
        readl_relaxed(base + offset);
}

static void u2o_clear(void __iomem *base, unsigned int offset,
                unsigned int value)
{
        u32 reg;

        reg = readl_relaxed(base + offset);
        reg &= ~value;
        writel_relaxed(reg, base + offset);
        readl_relaxed(base + offset);
}

static int mmp3_usb_phy_init(struct phy *phy)
{
        struct mmp3_usb_phy *mmp3_usb_phy = phy_get_drvdata(phy);
        void __iomem *base = mmp3_usb_phy->base;

        if (cpu_is_mmp3_a0()) {
                u2o_clear(base, USB2_PLL_REG0, (USB2_PLL_FBDIV_MASK_MMP3
                        | USB2_PLL_REFDIV_MASK_MMP3));
                u2o_set(base, USB2_PLL_REG0,
                        0xd << USB2_PLL_REFDIV_SHIFT_MMP3
                        | 0xf0 << USB2_PLL_FBDIV_SHIFT_MMP3);
        } else if (cpu_is_mmp3_b0()) {
                u2o_clear(base, USB2_PLL_REG0, USB2_PLL_REFDIV_MASK_MMP3_B0
                        | USB2_PLL_FBDIV_MASK_MMP3_B0);
                u2o_set(base, USB2_PLL_REG0,
                        0xd << USB2_PLL_REFDIV_SHIFT_MMP3_B0
                        | 0xf0 << USB2_PLL_FBDIV_SHIFT_MMP3_B0);
        } else {
                dev_err(&phy->dev, "unsupported silicon revision\n");
                return -ENODEV;
        }

        u2o_clear(base, USB2_PLL_REG1, USB2_PLL_PU_PLL_MASK
                | USB2_PLL_ICP_MASK_MMP3
                | USB2_PLL_KVCO_MASK_MMP3
                | USB2_PLL_CALI12_MASK_MMP3);
        u2o_set(base, USB2_PLL_REG1, 1 << USB2_PLL_PU_PLL_SHIFT_MMP3
                | 1 << USB2_PLL_LOCK_BYPASS_SHIFT_MMP3
                | 3 << USB2_PLL_ICP_SHIFT_MMP3
                | 3 << USB2_PLL_KVCO_SHIFT_MMP3
                | 3 << USB2_PLL_CAL12_SHIFT_MMP3);

        u2o_clear(base, USB2_TX_REG0, USB2_TX_IMPCAL_VTH_MASK_MMP3);
        u2o_set(base, USB2_TX_REG0, 2 << USB2_TX_IMPCAL_VTH_SHIFT_MMP3);

        u2o_clear(base, USB2_TX_REG1, USB2_TX_VDD12_MASK_MMP3
                | USB2_TX_AMP_MASK_MMP3
                | USB2_TX_CK60_PHSEL_MASK_MMP3);
        u2o_set(base, USB2_TX_REG1, 3 << USB2_TX_VDD12_SHIFT_MMP3
                | 4 << USB2_TX_AMP_SHIFT_MMP3
                | 4 << USB2_TX_CK60_PHSEL_SHIFT_MMP3);

        u2o_clear(base, USB2_TX_REG2, 3 << USB2_TX_DRV_SLEWRATE_SHIFT);
        u2o_set(base, USB2_TX_REG2, 2 << USB2_TX_DRV_SLEWRATE_SHIFT);

        u2o_clear(base, USB2_RX_REG0, USB2_RX_SQ_THRESH_MASK_MMP3);
        u2o_set(base, USB2_RX_REG0, 0xa << USB2_RX_SQ_THRESH_SHIFT_MMP3);

        u2o_set(base, USB2_ANA_REG1, 0x1 << USB2_ANA_PU_ANA_SHIFT_MMP3);

        u2o_set(base, USB2_OTG_REG0, 0x1 << USB2_OTG_PU_OTG_SHIFT_MMP3);

        return 0;
}

static int mmp3_usb_phy_calibrate(struct phy *phy)
{
        struct mmp3_usb_phy *mmp3_usb_phy = phy_get_drvdata(phy);
        void __iomem *base = mmp3_usb_phy->base;
        int loops;

        /*
         * PLL VCO and TX Impedance Calibration Timing:
         *
         *                _____________________________________
         * PU  __________|
         *                        _____________________________
         * VCOCAL START _________|
         *                                 ___
         * REG_RCAL_START ________________|   |________|_______
         *               | 200us | 400us  | 40| 400us  | USB PHY READY
         */

        udelay(200);
        u2o_set(base, USB2_PLL_REG1, 1 << USB2_PLL_VCOCAL_START_SHIFT_MMP3);
        udelay(400);
        u2o_set(base, USB2_TX_REG0, 1 << USB2_TX_RCAL_START_SHIFT_MMP3);
        udelay(40);
        u2o_clear(base, USB2_TX_REG0, 1 << USB2_TX_RCAL_START_SHIFT_MMP3);
        udelay(400);

        loops = 0;
        while ((u2o_get(base, USB2_PLL_REG1) & USB2_PLL_READY_MASK_MMP3) == 0) {
                mdelay(1);
                loops++;
                if (loops > 100) {
                        dev_err(&phy->dev, "PLL_READY not set after 100mS.\n");
                        return -ETIMEDOUT;
                }
        }

        return 0;
}

static const struct phy_ops mmp3_usb_phy_ops = {
        .init           = mmp3_usb_phy_init,
        .calibrate      = mmp3_usb_phy_calibrate,
        .owner          = THIS_MODULE,
};

static const struct of_device_id mmp3_usb_phy_of_match[] = {
        { .compatible = "marvell,mmp3-usb-phy", },
        { },
};
MODULE_DEVICE_TABLE(of, mmp3_usb_phy_of_match);

static int mmp3_usb_phy_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct mmp3_usb_phy *mmp3_usb_phy;
        struct phy_provider *provider;

        mmp3_usb_phy = devm_kzalloc(dev, sizeof(*mmp3_usb_phy), GFP_KERNEL);
        if (!mmp3_usb_phy)
                return -ENOMEM;

        mmp3_usb_phy->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(mmp3_usb_phy->base)) {
                dev_err(dev, "failed to remap PHY regs\n");
                return PTR_ERR(mmp3_usb_phy->base);
        }

        mmp3_usb_phy->phy = devm_phy_create(dev, NULL, &mmp3_usb_phy_ops);
        if (IS_ERR(mmp3_usb_phy->phy)) {
                dev_err(dev, "failed to create PHY\n");
                return PTR_ERR(mmp3_usb_phy->phy);
        }

        phy_set_drvdata(mmp3_usb_phy->phy, mmp3_usb_phy);
        provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
        if (IS_ERR(provider)) {
                dev_err(dev, "failed to register PHY provider\n");
                return PTR_ERR(provider);
        }

        return 0;
}

static struct platform_driver mmp3_usb_phy_driver = {
        .probe          = mmp3_usb_phy_probe,
        .driver         = {
                .name   = "mmp3-usb-phy",
                .of_match_table = mmp3_usb_phy_of_match,
        },
};
module_platform_driver(mmp3_usb_phy_driver);

MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
MODULE_DESCRIPTION("Marvell MMP3 USB PHY Driver");
MODULE_LICENSE("GPL v2");