Re: [PATCH 2/6] phy: am654-mmc-phy: Add Support for MMC PHY on AM654 Devices

From: Ulf Hansson
Date: Tue Oct 09 2018 - 03:31:18 EST


On 9 October 2018 at 07:18, Kishon Vijay Abraham I <kishon@xxxxxx> wrote:
> Hi Uffe,
>
> On Monday 08 October 2018 05:02 PM, Ulf Hansson wrote:
>> 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.
>
> yes, I'll pick this in my tree.
>

So I have picked patch3, 4 and 5. The rest I leave for you to pick up then.

Kind regards
Uffe

>>
>> Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>
> Thanks
> Kishon
>
>>
>> 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
>>>