Re: [PATCH 2/6] phy: am654-mmc-phy: Add Support for MMC PHY on AM654 Devices
From: Ulf Hansson
Date: Mon Oct 08 2018 - 07:33:11 EST
On 4 October 2018 at 13:14, Faiz Abbas <faiz_abbas@xxxxxx> wrote:
> Add driver support for the MMC physical layer present
> on TI's AM654 devices.
>
> Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
> Signed-off-by: Sekhar Nori <nsekhar@xxxxxx>
I assume Kishon would like to pick up this through his tree? If not,
please tell and I can do it, with his ack.
Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Kind regards
Uffe
> ---
> drivers/phy/ti/Kconfig | 7 +
> drivers/phy/ti/Makefile | 1 +
> drivers/phy/ti/phy-am654-mmc.c | 291 +++++++++++++++++++++++++++++++++
> 3 files changed, 299 insertions(+)
> create mode 100644 drivers/phy/ti/phy-am654-mmc.c
>
> diff --git a/drivers/phy/ti/Kconfig b/drivers/phy/ti/Kconfig
> index 20503562666c..ea5fe4db01c8 100644
> --- a/drivers/phy/ti/Kconfig
> +++ b/drivers/phy/ti/Kconfig
> @@ -76,3 +76,10 @@ config TWL4030_USB
> family chips (including the TWL5030 and TPS659x0 devices).
> This transceiver supports high and full speed devices plus,
> in host mode, low speed.
> +
> +config PHY_AM654_MMC
> + bool "TI AM654 MMC PHY Support"
> + select GENERIC_PHY
> + help
> + This option enables support for the Physical layer for MMC host
> + controllers present on TI AM654 SOCs.
> diff --git a/drivers/phy/ti/Makefile b/drivers/phy/ti/Makefile
> index 9f361756eaf2..5b2db2d164a5 100644
> --- a/drivers/phy/ti/Makefile
> +++ b/drivers/phy/ti/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_OMAP_USB2) += phy-omap-usb2.o
> obj-$(CONFIG_TI_PIPE3) += phy-ti-pipe3.o
> obj-$(CONFIG_PHY_TUSB1210) += phy-tusb1210.o
> obj-$(CONFIG_TWL4030_USB) += phy-twl4030-usb.o
> +obj-$(CONFIG_PHY_AM654_MMC) += phy-am654-mmc.o
> diff --git a/drivers/phy/ti/phy-am654-mmc.c b/drivers/phy/ti/phy-am654-mmc.c
> new file mode 100644
> index 000000000000..91255947fb67
> --- /dev/null
> +++ b/drivers/phy/ti/phy-am654-mmc.c
> @@ -0,0 +1,291 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * phy-am654-mmc.c - MMC PHY driver for TI's AM654 SOCs
> + *
> + * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com
> + *
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/printk.h>
> +#include <linux/regmap.h>
> +
> +/* MMC PHY Registers */
> +#define PHYCTRL_CTRL1_REG 0x00
> +#define PHYCTRL_CTRL2_REG 0x04
> +#define PHYCTRL_CTRL3_REG 0x08
> +#define PHYCTRL_CTRL4_REG 0x0C
> +#define PHYCTRL_CTRL5_REG 0x10
> +#define PHYCTRL_CTRL6_REG 0x14
> +#define PHYCTRL_STAT1_REG 0x30
> +#define PHYCTRL_STAT2_REG 0x34
> +
> +#define IOMUX_ENABLE_SHIFT 31
> +#define IOMUX_ENABLE_MASK BIT(IOMUX_ENABLE_SHIFT)
> +#define OTAPDLYENA_SHIFT 20
> +#define OTAPDLYENA_MASK BIT(OTAPDLYENA_SHIFT)
> +#define OTAPDLYSEL_SHIFT 12
> +#define OTAPDLYSEL_MASK GENMASK(15, 12)
> +#define STRBSEL_SHIFT 24
> +#define STRBSEL_MASK GENMASK(27, 24)
> +#define SEL50_SHIFT 8
> +#define SEL50_MASK BIT(SEL50_SHIFT)
> +#define SEL100_SHIFT 9
> +#define SEL100_MASK BIT(SEL100_SHIFT)
> +#define DLL_TRIM_ICP_SHIFT 4
> +#define DLL_TRIM_ICP_MASK GENMASK(7, 4)
> +#define DR_TY_SHIFT 20
> +#define DR_TY_MASK GENMASK(22, 20)
> +#define ENDLL_SHIFT 1
> +#define ENDLL_MASK BIT(ENDLL_SHIFT)
> +#define DLLRDY_SHIFT 0
> +#define DLLRDY_MASK BIT(DLLRDY_SHIFT)
> +#define PDB_SHIFT 0
> +#define PDB_MASK BIT(PDB_SHIFT)
> +#define CALDONE_SHIFT 1
> +#define CALDONE_MASK BIT(CALDONE_SHIFT)
> +
> +#define DRIVER_STRENGTH_50_OHM 0x0
> +#define DRIVER_STRENGTH_33_OHM 0x1
> +#define DRIVER_STRENGTH_66_OHM 0x2
> +#define DRIVER_STRENGTH_100_OHM 0x3
> +#define DRIVER_STRENGTH_40_OHM 0x4
> +
> +static struct regmap_config am654_mmc_phy_regmap_config = {
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> + .fast_io = true,
> +};
> +
> +struct am654_mmc_phy {
> + struct regmap *reg_base;
> + struct clk *mmcclk;
> + int otap_del_sel;
> + int trm_icp;
> + int drv_strength;
> +};
> +
> +static int am654_mmc_phy_init(struct phy *phy)
> +{
> + struct am654_mmc_phy *mmc_phy = phy_get_drvdata(phy);
> + int ret;
> + u32 val;
> +
> + /* Reset registers to default value */
> + regmap_write(mmc_phy->reg_base, PHYCTRL_CTRL1_REG, 0x10000);
> + regmap_write(mmc_phy->reg_base, PHYCTRL_CTRL4_REG, 0x0);
> + regmap_write(mmc_phy->reg_base, PHYCTRL_CTRL5_REG, 0x0);
> +
> + /* Calibrate IO lines */
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL1_REG,
> + PDB_MASK, PDB_MASK);
> + ret = regmap_read_poll_timeout(mmc_phy->reg_base, PHYCTRL_STAT1_REG,
> + val, val & CALDONE_MASK, 1, 20);
> + if (ret)
> + return ret;
> +
> + /* Enable pins by setting the IO mux to 0 */
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL1_REG,
> + IOMUX_ENABLE_MASK, 0);
> +
> + mmc_phy->mmcclk = clk_get(&phy->dev, "mmcclk");
> + if (IS_ERR(mmc_phy->mmcclk)) {
> + dev_err(&phy->dev, "Error getting mmcclk");
> + return PTR_ERR(mmc_phy->mmcclk);
> + }
> +
> + return 0;
> +}
> +
> +static int am654_mmc_phy_exit(struct phy *phy)
> +{
> + struct am654_mmc_phy *mmc_phy = phy_get_drvdata(phy);
> +
> + clk_put(mmc_phy->mmcclk);
> +
> + return 0;
> +}
> +
> +static int am654_mmc_phy_power_on(struct phy *phy)
> +{
> + struct am654_mmc_phy *mmc_phy = phy_get_drvdata(phy);
> + u32 mask, val;
> + int sel50, sel100;
> + int rate;
> +
> + /* Setup DLL Output TAP delay */
> + mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK;
> + val = (1 << OTAPDLYENA_SHIFT) |
> + (mmc_phy->otap_del_sel << OTAPDLYSEL_SHIFT);
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL4_REG,
> + mask, val);
> +
> + rate = clk_get_rate(mmc_phy->mmcclk);
> + switch (rate) {
> + case 200000000:
> + sel50 = 0;
> + sel100 = 0;
> + break;
> + case 100000000:
> + sel50 = 0;
> + sel100 = 1;
> + break;
> + default:
> + sel50 = 1;
> + sel100 = 0;
> + }
> +
> + /* Configure PHY DLL frequency */
> + mask = SEL50_MASK | SEL100_MASK;
> + val = (sel50 << SEL50_SHIFT) | (sel100 << SEL100_SHIFT);
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL5_REG,
> + mask, val);
> +
> + /* Configure DLL TRIM */
> + mask = DLL_TRIM_ICP_MASK;
> + val = mmc_phy->trm_icp << DLL_TRIM_ICP_SHIFT;
> +
> + /* Configure DLL driver strength */
> + mask |= DR_TY_MASK;
> + val |= mmc_phy->drv_strength << DR_TY_SHIFT;
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL1_REG, mask, val);
> +
> + /* Enable DLL */
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL1_REG,
> + ENDLL_MASK, 0x1 << ENDLL_SHIFT);
> +
> + /*
> + * Poll for DLL ready. Use a one second timeout.
> + * Works in all experiments done so far
> + */
> + return regmap_read_poll_timeout(mmc_phy->reg_base, PHYCTRL_STAT1_REG,
> + val, val & DLLRDY_MASK, 1000, 1000000);
> +
> +}
> +
> +static int am654_mmc_phy_power_off(struct phy *phy)
> +{
> + struct am654_mmc_phy *mmc_phy = phy_get_drvdata(phy);
> +
> + /* Disable DLL */
> + regmap_update_bits(mmc_phy->reg_base, PHYCTRL_CTRL1_REG,
> + ENDLL_MASK, 0);
> +
> + /* Reset registers to default value except PDB */
> + regmap_write(mmc_phy->reg_base, PHYCTRL_CTRL1_REG,
> + 0x10000 | PDB_MASK);
> + regmap_write(mmc_phy->reg_base, PHYCTRL_CTRL4_REG, 0x0);
> + regmap_write(mmc_phy->reg_base, PHYCTRL_CTRL5_REG, 0x0);
> +
> + return 0;
> +}
> +
> +static const struct phy_ops ops = {
> + .init = am654_mmc_phy_init,
> + .exit = am654_mmc_phy_exit,
> + .power_on = am654_mmc_phy_power_on,
> + .power_off = am654_mmc_phy_power_off,
> + .owner = THIS_MODULE,
> +};
> +
> +static int am654_mmc_phy_probe(struct platform_device *pdev)
> +{
> + struct phy_provider *phy_provider;
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct am654_mmc_phy *mmc_phy;
> + struct phy *generic_phy;
> + struct resource *res;
> + void __iomem *base;
> + struct regmap *map;
> + int drv_strength;
> + int err;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + map = devm_regmap_init_mmio(dev, base, &am654_mmc_phy_regmap_config);
> + if (IS_ERR(map)) {
> + dev_err(dev, "could not initialize regmap\n");
> + return PTR_ERR(map);
> + }
> +
> + mmc_phy = devm_kzalloc(dev, sizeof(struct am654_mmc_phy), GFP_KERNEL);
> + if (!mmc_phy)
> + return -ENOMEM;
> +
> + mmc_phy->reg_base = map;
> + err = of_property_read_u32(np, "ti,otap-del-sel",
> + &mmc_phy->otap_del_sel);
> + if (err)
> + return err;
> +
> + err = of_property_read_u32(np, "ti,trm-icp",
> + &mmc_phy->trm_icp);
> + if (err)
> + return err;
> +
> + err = of_property_read_u32(np, "ti,driver-strength-ohm", &drv_strength);
> + if (err)
> + return err;
> +
> + switch (drv_strength) {
> + case 50:
> + mmc_phy->drv_strength = DRIVER_STRENGTH_50_OHM;
> + break;
> + case 33:
> + mmc_phy->drv_strength = DRIVER_STRENGTH_33_OHM;
> + break;
> + case 66:
> + mmc_phy->drv_strength = DRIVER_STRENGTH_66_OHM;
> + break;
> + case 100:
> + mmc_phy->drv_strength = DRIVER_STRENGTH_100_OHM;
> + break;
> + case 40:
> + mmc_phy->drv_strength = DRIVER_STRENGTH_40_OHM;
> + break;
> + default:
> + dev_err(dev, "Invalid driver strength\n");
> + return -EINVAL;
> + }
> +
> + generic_phy = devm_phy_create(dev, dev->of_node, &ops);
> + if (IS_ERR(generic_phy)) {
> + dev_err(dev, "failed to create PHY\n");
> + return PTR_ERR(generic_phy);
> + }
> +
> + phy_set_drvdata(generic_phy, mmc_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 am654_mmc_phy_dt_ids[] = {
> + { .compatible = "ti,am654-mmc-phy" },
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(of, am654_mmc_phy_dt_ids);
> +
> +static struct platform_driver am654_mmc_phy_driver = {
> + .probe = am654_mmc_phy_probe,
> + .driver = {
> + .name = "am654-mmc-phy",
> + .of_match_table = am654_mmc_phy_dt_ids,
> + },
> +};
> +
> +module_platform_driver(am654_mmc_phy_driver);
> +
> +MODULE_AUTHOR("Faiz Abbas <faiz_abbas@xxxxxx>");
> +MODULE_DESCRIPTION("TI AM654 MMC PHY driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.18.0
>