Re: [PATCH v3 1/2] scsi: ufs: Refactor ufshcd_setup_clocks() to remove skip_ref_clk
From: Asutosh Das (asd)
Date: Tue Dec 01 2020 - 11:53:26 EST
On 11/30/2020 7:11 PM, Can Guo wrote:
On 2020-12-01 07:01, Asutosh Das (asd) wrote:
On 11/25/2020 6:01 PM, Can Guo wrote:
Remove the param skip_ref_clk from __ufshcd_setup_clocks(), but keep
a flag
in struct ufs_clk_info to tell whether a clock can be disabled or not
while
the link is active.
Reviewed-by: Hongwu Su<hongwus@xxxxxxxxxxxxxx>
Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>
Reviewed-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd-pltfrm.c | 2 ++
drivers/scsi/ufs/ufshcd.c | 29 +++++++++--------------------
drivers/scsi/ufs/ufshcd.h | 3 +++
3 files changed, 14 insertions(+), 20 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c
b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 3db0af6..873ef14 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -92,6 +92,8 @@ static int ufshcd_parse_clock_info(struct ufs_hba
*hba)
clki->min_freq = clkfreq[i];
clki->max_freq = clkfreq[i+1];
clki->name = kstrdup(name, GFP_KERNEL);
+ if (!strcmp(name, "ref_clk"))
+ clki->keep_link_active = true;
dev_dbg(dev, "%s: min %u max %u name %s\n", "freq-table-hz",
clki->min_freq, clki->max_freq, clki->name);
list_add_tail(&clki->list, &hba->clk_list_head);
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index a7857f6..44254c9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -221,8 +221,6 @@ static int ufshcd_eh_host_reset_handler(struct
scsi_cmnd *cmd);
static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
static void ufshcd_hba_exit(struct ufs_hba *hba);
static int ufshcd_probe_hba(struct ufs_hba *hba, bool async);
-static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
- bool skip_ref_clk);
static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on);
static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba);
static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba
*hba);
@@ -1707,11 +1705,7 @@ static void ufshcd_gate_work(struct
work_struct *work)
ufshcd_disable_irq(hba);
- if (!ufshcd_is_link_active(hba))
- ufshcd_setup_clocks(hba, false);
- else
- /* If link is active, device ref_clk can't be switched off */
- __ufshcd_setup_clocks(hba, false, true);
+ ufshcd_setup_clocks(hba, false);
/*
* In case you are here to cancel this work the gating state
@@ -7990,8 +7984,7 @@ static int ufshcd_init_hba_vreg(struct ufs_hba
*hba)
return 0;
}
-static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
- bool skip_ref_clk)
+static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
{
int ret = 0;
struct ufs_clk_info *clki;
@@ -8009,7 +8002,12 @@ static int __ufshcd_setup_clocks(struct
ufs_hba *hba, bool on,
list_for_each_entry(clki, head, list) {
if (!IS_ERR_OR_NULL(clki->clk)) {
- if (skip_ref_clk && !strcmp(clki->name, "ref_clk"))
+ /*
+ * Don't disable clocks which are needed
+ * to keep the link active.
+ */
+ if (ufshcd_is_link_active(hba) &&
+ clki->keep_link_active)
continue;
clk_state_changed = on ^ clki->enabled;
@@ -8054,11 +8052,6 @@ static int __ufshcd_setup_clocks(struct
ufs_hba *hba, bool on,
return ret;
}
-static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
-{
- return __ufshcd_setup_clocks(hba, on, false);
-}
-
static int ufshcd_init_clocks(struct ufs_hba *hba)
{
int ret = 0;
@@ -8577,11 +8570,7 @@ static int ufshcd_suspend(struct ufs_hba *hba,
enum ufs_pm_op pm_op)
*/
ufshcd_disable_irq(hba);
- if (!ufshcd_is_link_active(hba))
- ufshcd_setup_clocks(hba, false);
- else
- /* If link is active, device ref_clk can't be switched off */
- __ufshcd_setup_clocks(hba, false, true);
+ ufshcd_setup_clocks(hba, false);
if (ufshcd_is_clkgating_allowed(hba)) {
hba->clk_gating.state = CLKS_OFF;
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 66e5338..6f0f2d4 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -229,6 +229,8 @@ struct ufs_dev_cmd {
* @max_freq: maximum frequency supported by the clock
* @min_freq: min frequency that can be used for clock scaling
* @curr_freq: indicates the current frequency that it is set to
+ * @keep_link_active: indicates that the clk should not be disabled if
+ link is active
* @enabled: variable to check against multiple enable/disable
*/
struct ufs_clk_info {
@@ -238,6 +240,7 @@ struct ufs_clk_info {
u32 max_freq;
u32 min_freq;
u32 curr_freq;
+ bool keep_link_active;
Nitpick - How about 'always-on' instead of 'keep_link_active'?
Hi Asutosh,
But it is not always-on, during suspend, it is on when rpm/spm-lvl is 1
and 2, off when rpm/spm-lvl is 3, 4 and 5, depending on the link state.
Understood & agree.
Thanks,
Can Guo.
bool enabled;
};
--
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