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

From: Alim Akhtar
Date: Wed Oct 14 2015 - 12:13:49 EST


Hi,

On Wed, Oct 14, 2015 at 9:31 PM, Kishon Vijay Abraham I <kishon@xxxxxx> wrote:
> Hi,
>
> On Wednesday 14 October 2015 06:25 PM, Alim Akhtar wrote:
>> From: Seungwon Jeon <essuuj@xxxxxxxxx>
>>
>> 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@xxxxxxxxx>
>> Signed-off-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
>> Cc: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>> 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@xxxxxxxxx>
>> + *
>> + * 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,

> Thanks
> Kishon
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--
Regards,
Alim
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