Re: [PATCH v4 02/11] phy: exynos-ufs: add UFS PHY driver for EXYNOS SoC

[Kishon Vijay Abraham I <kishon@ti.com>]

On Wednesday 14 October 2015 09:43 PM, Alim Akhtar wrote:
> Hi,
> 
> On Wed, Oct 14, 2015 at 9:31 PM, Kishon Vijay Abraham I <kishon@ti.com> wrote:
>> Hi,
>>
>> On Wednesday 14 October 2015 06:25 PM, Alim Akhtar wrote:
>>> From: Seungwon Jeon <essuuj@gmail.com>
>>>
>>> This patch introduces Exynos UFS PHY driver. This driver
>>> supports to deal with phy calibration and power control
>>> according to UFS host driver's behavior.
>>>
>>> Signed-off-by: Seungwon Jeon <essuuj@gmail.com>
>>> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
>>> Cc: Kishon Vijay Abraham I <kishon@ti.com>
>>> ---
>>>  drivers/phy/Kconfig                |    7 +
>>>  drivers/phy/Makefile               |    1 +
>>>  drivers/phy/phy-exynos-ufs.c       |  257 ++++++++++++++++++++++++++++++++++++
>>>  drivers/phy/phy-exynos-ufs.h       |   88 ++++++++++++
>>>  drivers/phy/phy-exynos7-ufs.h      |   89 +++++++++++++
>>>  include/linux/phy/phy-exynos-ufs.h |  101 ++++++++++++++
>>>  6 files changed, 543 insertions(+)
>>>  create mode 100644 drivers/phy/phy-exynos-ufs.c
>>>  create mode 100644 drivers/phy/phy-exynos-ufs.h
>>>  create mode 100644 drivers/phy/phy-exynos7-ufs.h
>>>  create mode 100644 include/linux/phy/phy-exynos-ufs.h
>>>
>>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>>> index 47da573d0bab..499eec4a967c 100644
>>> --- a/drivers/phy/Kconfig
>>> +++ b/drivers/phy/Kconfig
>>> @@ -371,4 +371,11 @@ config PHY_BRCMSTB_SATA
>>>         Enable this to support the SATA3 PHY on 28nm Broadcom STB SoCs.
>>>         Likely useful only with CONFIG_SATA_BRCMSTB enabled.
>>>
>>> +config PHY_EXYNOS_UFS
>>> +     tristate "EXYNOS SoC series UFS PHY driver"
>>> +     depends on OF && ARCH_EXYNOS || COMPILE_TEST
>>> +     select GENERIC_PHY
>>> +     help
>>> +       Support for UFS PHY on Samsung EXYNOS chipsets.
>>> +
>>>  endmenu
>>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
>>> index a5b18c18fc12..2a312ca20795 100644
>>> --- a/drivers/phy/Makefile
>>> +++ b/drivers/phy/Makefile
>>> @@ -46,3 +46,4 @@ obj-$(CONFIG_PHY_QCOM_UFS)  += phy-qcom-ufs-qmp-14nm.o
>>>  obj-$(CONFIG_PHY_TUSB1210)           += phy-tusb1210.o
>>>  obj-$(CONFIG_PHY_BRCMSTB_SATA)               += phy-brcmstb-sata.o
>>>  obj-$(CONFIG_PHY_PISTACHIO_USB)              += phy-pistachio-usb.o
>>> +obj-$(CONFIG_PHY_EXYNOS_UFS) += phy-exynos-ufs.o
>>> diff --git a/drivers/phy/phy-exynos-ufs.c b/drivers/phy/phy-exynos-ufs.c
>>> new file mode 100644
>>> index 000000000000..77330b85e3f8
>>> --- /dev/null
>>> +++ b/drivers/phy/phy-exynos-ufs.c
>>> @@ -0,0 +1,257 @@
>>> +/*
>>> + * UFS PHY driver for Samsung EXYNOS SoC
>>> + *
>>> + * Copyright (C) 2015 Samsung Electronics Co., Ltd.
>>> + * Author: Seungwon Jeon <essuuj@gmail.com>
>>> + *
>>> + * This program is free software; you can redistribute it and/or modify
>>> + * it under the terms of the GNU General Public License as published by
>>> + * the Free Software Foundation; either version 2 of the License, or
>>> + * (at your option) any later version.
>>> + */
>>> +#include <linux/clk.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/err.h>
>>> +#include <linux/io.h>
>>> +#include <linux/iopoll.h>
>>> +#include <linux/mfd/syscon.h>
>>> +#include <linux/module.h>
>>> +#include <linux/of.h>
>>> +#include <linux/phy/phy.h>
>>> +#include <linux/phy/phy-exynos-ufs.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/regmap.h>
>>> +
>>> +#include "phy-exynos-ufs.h"
>>> +
>>> +#define for_each_phy_lane(phy, i) \
>>> +     for (i = 0; i < (phy)->lane_cnt; i++)
>>> +#define for_each_phy_cfg(cfg) \
>>> +     for (; (cfg)->id; (cfg)++)
>>> +
>>> +#define PHY_DEF_LANE_CNT     1
>>> +
>>> +static void exynos_ufs_phy_config(struct exynos_ufs_phy *phy,
>>> +                     const struct exynos_ufs_phy_cfg *cfg, u8 lane)
>>> +{
>>> +     enum {LANE_0, LANE_1}; /* lane index */
>>> +
>>> +     switch (lane) {
>>> +     case LANE_0:
>>> +             writel(cfg->val, (phy)->reg_pma + cfg->off_0);
>>> +             break;
>>> +     case LANE_1:
>>> +             if (cfg->id == PHY_TRSV_BLK)
>>> +                     writel(cfg->val, (phy)->reg_pma + cfg->off_1);
>>> +             break;
>>> +     }
>>> +}
>>> +
>>> +static bool match_cfg_to_pwr_mode(u8 desc, u8 required_pwr)
>>> +{
>>> +     if (IS_PWR_MODE_ANY(desc))
>>> +             return true;
>>> +
>>> +     if (IS_PWR_MODE_HS(required_pwr) && IS_PWR_MODE_HS_ANY(desc))
>>> +             return true;
>>> +
>>> +     if (COMP_PWR_MODE(required_pwr, desc))
>>> +             return true;
>>> +
>>> +     if (COMP_PWR_MODE_MD(required_pwr, desc) &&
>>> +         COMP_PWR_MODE_GEAR(required_pwr, desc) &&
>>> +         COMP_PWR_MODE_SER(required_pwr, desc))
>>> +             return true;
>>> +
>>> +     return false;
>>> +}
>>> +
>>> +static int exynos_ufs_phy_calibrate(struct phy *phy,
>>> +                                 enum phy_cfg_tag tag, u8 pwr)
>>> +{
>>> +     struct exynos_ufs_phy *ufs_phy = get_exynos_ufs_phy(phy);
>>> +     struct exynos_ufs_phy_cfg **cfgs = ufs_phy->cfg;
>>> +     const struct exynos_ufs_phy_cfg *cfg;
>>> +     int i;
>>> +
>>> +     if (unlikely(tag < CFG_PRE_INIT || tag >= CFG_TAG_MAX)) {
>>> +             dev_err(ufs_phy->dev, "invalid phy config index %d\n", tag);
>>> +             return -EINVAL;
>>> +     }
>>> +
>>> +     cfg = cfgs[tag];
>>> +     if (!cfg)
>>> +             goto out;
>>> +
>>> +     for_each_phy_cfg(cfg) {
>>> +             for_each_phy_lane(ufs_phy, i) {
>>> +                     if (match_cfg_to_pwr_mode(cfg->desc, pwr))
>>> +                             exynos_ufs_phy_config(ufs_phy, cfg, i);
>>> +             }
>>> +     }
>>> +
>>> +out:
>>> +     return 0;
>>> +}
>>> +
>>> +static void exynos_ufs_phy_set_lane_cnt(struct phy *phy, u8 lane_cnt)
>>> +{
>>> +     struct exynos_ufs_phy *ufs_phy = get_exynos_ufs_phy(phy);
>>> +
>>> +     ufs_phy->lane_cnt = lane_cnt;
>>> +}
>>> +
>>> +static int exynos_ufs_phy_wait_for_lock_acq(struct phy *phy)
>>> +{
>>> +     struct exynos_ufs_phy *ufs_phy = get_exynos_ufs_phy(phy);
>>> +     const unsigned int timeout_us = 100000;
>>> +     const unsigned int sleep_us = 10;
>>> +     u32 val;
>>> +     int err;
>>> +
>>> +     err = readl_poll_timeout(
>>> +                     ufs_phy->reg_pma + PHY_APB_ADDR(PHY_PLL_LOCK_STATUS),
>>> +                     val, (val & PHY_PLL_LOCK_BIT), sleep_us, timeout_us);
>>> +     if (err) {
>>> +             dev_err(ufs_phy->dev,
>>> +                     "failed to get phy pll lock acquisition %d\n", err);
>>> +             goto out;
>>> +     }
>>> +
>>> +     err = readl_poll_timeout(
>>> +                     ufs_phy->reg_pma + PHY_APB_ADDR(PHY_CDR_LOCK_STATUS),
>>> +                     val, (val & PHY_CDR_LOCK_BIT), sleep_us, timeout_us);
>>> +     if (err) {
>>> +             dev_err(ufs_phy->dev,
>>> +                     "failed to get phy cdr lock acquisition %d\n", err);
>>> +             goto out;
>>> +     }
>>> +
>>> +out:
>>> +     return err;
>>> +}
>>> +
>>> +static int exynos_ufs_phy_power_on(struct phy *phy)
>>> +{
>>> +     struct exynos_ufs_phy *_phy = get_exynos_ufs_phy(phy);
>>> +
>>> +     exynos_ufs_phy_ctrl_isol(_phy, false);
>>> +     return 0;
>>> +}
>>> +
>>> +static int exynos_ufs_phy_power_off(struct phy *phy)
>>> +{
>>> +     struct exynos_ufs_phy *_phy = get_exynos_ufs_phy(phy);
>>> +
>>> +     exynos_ufs_phy_ctrl_isol(_phy, true);
>>> +     return 0;
>>> +}
>>> +
>>> +static struct phy_ops exynos_ufs_phy_ops = {
>>> +     .power_on       = exynos_ufs_phy_power_on,
>>> +     .power_off      = exynos_ufs_phy_power_off,
>>> +};
>>> +
>>> +static struct exynos_ufs_phy_specific_ops phy_specific_ops = {
>>> +     .calibrate_phy = exynos_ufs_phy_calibrate,
>>> +     .set_lane_cnt = exynos_ufs_phy_set_lane_cnt,
>>> +     .wait_for_lock_acq = exynos_ufs_phy_wait_for_lock_acq,
>>> +};
>>
>> I'd like avoiding custom phy ops. Can you forward me the entire series
>> so that it helps me in reviewing the use of these ops?
>>
> This is how it has been used in other phy drivers.
> 
> PTAL  https://lkml.org/lkml/2015/10/14/412
> 
> Let me know in case you want me to CC you on whole series.
> Thanks,

yes please.

Thanks
Kishon

> 
>> Thanks
>> Kishon
>> --
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> 
> 
>