Re: [PATCH 08/10] ufs-qcom: phy/hcd: Refactoring phy clock handling

From: Subhash Jadavani
Date: Tue Oct 18 2016 - 16:13:58 EST


On 2016-10-18 07:28, Vivek Gautam wrote:
Add phy clock enable code to phy_power_on/off callbacks, and
remove explicit calls to enable these phy clocks from the
ufs-qcom hcd driver.

Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx>
---

Changes since v1:
- staticized ufs_qcom_phy_enable(/disable)_ref_clk(),
- staticized ufs_qcom_phy_enable(/disable)_iface_clk()
- removed function declaration and export symbol for these APIs.

drivers/phy/phy-qcom-ufs.c | 36 ++++++++++++++++++------------------
drivers/scsi/ufs/ufs-qcom.c | 15 ---------------
include/linux/phy/phy-qcom-ufs.h | 18 ------------------
3 files changed, 18 insertions(+), 51 deletions(-)

diff --git a/drivers/phy/phy-qcom-ufs.c b/drivers/phy/phy-qcom-ufs.c
index 144b11f..a425cc2 100644
--- a/drivers/phy/phy-qcom-ufs.c
+++ b/drivers/phy/phy-qcom-ufs.c
@@ -373,10 +373,9 @@ out:
return ret;
}

-int ufs_qcom_phy_enable_ref_clk(struct phy *generic_phy)
+static int ufs_qcom_phy_enable_ref_clk(struct ufs_qcom_phy *phy)
{
int ret = 0;
- struct ufs_qcom_phy *phy = get_ufs_qcom_phy(generic_phy);

if (phy->is_ref_clk_enabled)
goto out;
@@ -423,7 +422,6 @@ out_disable_src:
out:
return ret;
}
-EXPORT_SYMBOL_GPL(ufs_qcom_phy_enable_ref_clk);

static
int ufs_qcom_phy_disable_vreg(struct device *dev,
@@ -448,10 +446,8 @@ out:
return ret;
}

-void ufs_qcom_phy_disable_ref_clk(struct phy *generic_phy)
+static void ufs_qcom_phy_disable_ref_clk(struct ufs_qcom_phy *phy)
{
- struct ufs_qcom_phy *phy = get_ufs_qcom_phy(generic_phy);
-
if (phy->is_ref_clk_enabled) {
clk_disable_unprepare(phy->ref_clk);
/*
@@ -464,7 +460,6 @@ void ufs_qcom_phy_disable_ref_clk(struct phy *generic_phy)
phy->is_ref_clk_enabled = false;
}
}
-EXPORT_SYMBOL_GPL(ufs_qcom_phy_disable_ref_clk);

#define UFS_REF_CLK_EN (1 << 5)

@@ -517,9 +512,8 @@ void ufs_qcom_phy_disable_dev_ref_clk(struct phy
*generic_phy)
EXPORT_SYMBOL_GPL(ufs_qcom_phy_disable_dev_ref_clk);

/* Turn ON M-PHY RMMI interface clocks */
-int ufs_qcom_phy_enable_iface_clk(struct phy *generic_phy)
+static int ufs_qcom_phy_enable_iface_clk(struct ufs_qcom_phy *phy)
{
- struct ufs_qcom_phy *phy = get_ufs_qcom_phy(generic_phy);
int ret = 0;

if (phy->is_iface_clk_enabled)
@@ -543,20 +537,16 @@ int ufs_qcom_phy_enable_iface_clk(struct phy *generic_phy)
out:
return ret;
}
-EXPORT_SYMBOL_GPL(ufs_qcom_phy_enable_iface_clk);

/* Turn OFF M-PHY RMMI interface clocks */
-void ufs_qcom_phy_disable_iface_clk(struct phy *generic_phy)
+void ufs_qcom_phy_disable_iface_clk(struct ufs_qcom_phy *phy)
{
- struct ufs_qcom_phy *phy = get_ufs_qcom_phy(generic_phy);
-
if (phy->is_iface_clk_enabled) {
clk_disable_unprepare(phy->tx_iface_clk);
clk_disable_unprepare(phy->rx_iface_clk);
phy->is_iface_clk_enabled = false;
}
}
-EXPORT_SYMBOL_GPL(ufs_qcom_phy_disable_iface_clk);

int ufs_qcom_phy_start_serdes(struct phy *generic_phy)
{
@@ -674,13 +664,20 @@ int ufs_qcom_phy_power_on(struct phy *generic_phy)
goto out_disable_phy;
}

- err = ufs_qcom_phy_enable_ref_clk(generic_phy);
+ err = ufs_qcom_phy_enable_iface_clk(phy_common);
if (err) {
- dev_err(dev, "%s enable phy ref clock failed, err=%d\n",
+ dev_err(dev, "%s enable phy iface clock failed, err=%d\n",
__func__, err);
goto out_disable_pll;
}

+ err = ufs_qcom_phy_enable_ref_clk(phy_common);
+ if (err) {
+ dev_err(dev, "%s enable phy ref clock failed, err=%d\n",
+ __func__, err);
+ goto out_disable_iface_clk;
+ }
+
/* enable device PHY ref_clk pad rail */
if (phy_common->vddp_ref_clk.reg) {
err = ufs_qcom_phy_enable_vreg(dev,
@@ -696,7 +693,9 @@ int ufs_qcom_phy_power_on(struct phy *generic_phy)
goto out;

out_disable_ref_clk:
- ufs_qcom_phy_disable_ref_clk(generic_phy);
+ ufs_qcom_phy_disable_ref_clk(phy_common);
+out_disable_iface_clk:
+ ufs_qcom_phy_disable_iface_clk(phy_common);
out_disable_pll:
ufs_qcom_phy_disable_vreg(dev, &phy_common->vdda_pll);
out_disable_phy:
@@ -715,7 +714,8 @@ int ufs_qcom_phy_power_off(struct phy *generic_phy)
if (phy_common->vddp_ref_clk.reg)
ufs_qcom_phy_disable_vreg(phy_common->dev,
&phy_common->vddp_ref_clk);
- ufs_qcom_phy_disable_ref_clk(generic_phy);
+ ufs_qcom_phy_disable_ref_clk(phy_common);
+ ufs_qcom_phy_disable_iface_clk(phy_common);

ufs_qcom_phy_disable_vreg(phy_common->dev, &phy_common->vdda_pll);
ufs_qcom_phy_disable_vreg(phy_common->dev, &phy_common->vdda_phy);
diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 3aedf73..6e4ce5f 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -1112,17 +1112,6 @@ static int ufs_qcom_setup_clocks(struct ufs_hba
*hba, bool on)
return 0;

if (on) {
- err = ufs_qcom_phy_enable_iface_clk(host->generic_phy);
- if (err)
- goto out;
-
- err = ufs_qcom_phy_enable_ref_clk(host->generic_phy);
- if (err) {
- dev_err(hba->dev, "%s enable phy ref clock failed, err=%d\n",
- __func__, err);
- ufs_qcom_phy_disable_iface_clk(host->generic_phy);
- goto out;
- }

Now that you are moving these ref clk enable/disable to phy_power_on/off and these phy_power_on/off are called only in runtime suspend/resume (3 seconds after last UFS access).
Goal is to disable the phy reference clock during aggressive gating (10ms from last UFS access) so shouldn't we call the phy_power_on/off from these setup_clocks() function as well?

/* enable the device ref clock for HS mode*/
if (ufshcd_is_hs_mode(&hba->pwr_info))
ufs_qcom_dev_ref_clk_ctrl(host, true);
@@ -1131,9 +1120,6 @@ static int ufs_qcom_setup_clocks(struct ufs_hba
*hba, bool on)
ufs_qcom_update_bus_bw_vote(host);

} else {
-
- /* M-PHY RMMI interface clocks can be turned off */
- ufs_qcom_phy_disable_iface_clk(host->generic_phy);
if (!ufs_qcom_is_link_active(hba))
/* disable device ref_clk */
ufs_qcom_dev_ref_clk_ctrl(host, false);
@@ -1146,7 +1132,6 @@ static int ufs_qcom_setup_clocks(struct ufs_hba
*hba, bool on)
dev_err(hba->dev, "%s: set bus vote failed %d\n",
__func__, err);

-out:
return err;
}

diff --git a/include/linux/phy/phy-qcom-ufs.h b/include/linux/phy/phy-qcom-ufs.h
index 9d18e9f..35c070e 100644
--- a/include/linux/phy/phy-qcom-ufs.h
+++ b/include/linux/phy/phy-qcom-ufs.h
@@ -18,22 +18,6 @@
#include "phy.h"

/**
- * ufs_qcom_phy_enable_ref_clk() - Enable the phy
- * ref clock.
- * @phy: reference to a generic phy
- *
- * returns 0 for success, and non-zero for error.
- */
-int ufs_qcom_phy_enable_ref_clk(struct phy *phy);
-
-/**
- * ufs_qcom_phy_disable_ref_clk() - Disable the phy
- * ref clock.
- * @phy: reference to a generic phy.
- */
-void ufs_qcom_phy_disable_ref_clk(struct phy *phy);
-
-/**
* ufs_qcom_phy_enable_dev_ref_clk() - Enable the device
* ref clock.
* @phy: reference to a generic phy.
@@ -47,8 +31,6 @@ void ufs_qcom_phy_enable_dev_ref_clk(struct phy *phy);
*/
void ufs_qcom_phy_disable_dev_ref_clk(struct phy *phy);

-int ufs_qcom_phy_enable_iface_clk(struct phy *phy);
-void ufs_qcom_phy_disable_iface_clk(struct phy *phy);
int ufs_qcom_phy_start_serdes(struct phy *phy);
int ufs_qcom_phy_set_tx_lane_enable(struct phy *phy, u32 tx_lanes);
int ufs_qcom_phy_calibrate_phy(struct phy *phy, bool is_rate_B);

--
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