[v3,3/8] scsi: ufs: core: Add a vop to map clock frequency to gear speed

Commit Message

Ziqi Chen Feb. 3, 2025, 8:11 a.m. UTC

From: Can Guo <[e-mail]>

Add a vop to map UFS host controller clock frequencies to the maximum
supported UFS high speed gear speeds. During clock scaling, we can map the
target clock frequency, demanded by devfreq, to the maximum supported gear
speed, so that devfreq can scale the gear to the highest gear speed
supported at the target clock frequency, instead of just scaling up/down
the gear between the min and max gear speeds.

Co-developed-by: Ziqi Chen <[e-mail]>
Signed-off-by: Ziqi Chen <[e-mail]>
Signed-off-by: Can Guo <[e-mail]>
---
v2 ->v3:
1. Remove the parameter 'gear' and use it as function return result.
2. Change "vops" into "vop" in commit message.
---
 drivers/ufs/core/ufshcd-priv.h | 8 ++++++++
 include/ufs/ufshcd.h           | 2 ++
 2 files changed, 10 insertions(+)

Comments

Bean Huo Feb. 3, 2025, 12:55 p.m. UTC | #1

On Mon, 2025-02-03 at 16:11 +0800, Ziqi Chen wrote:
> From: Can Guo <[e-mail]>
> 
> Add a vop to map UFS host controller clock frequencies to the maximum
> supported UFS high speed gear speeds. 

From the code, seems it is not "maximum" gear, it is corresponding UFS
Gear.

> During clock scaling, we canmap thetarget clock frequency, demanded
> by devfreq, to the maximum supported gear
> speed, so that devfreq can scale the gear to the highest gear speed
> supported at the target clock frequency, instead of just scaling
> up/down
> the gear between the min and max gear speeds.
> 
> Co-developed-by: Ziqi Chen <[e-mail]>
> Signed-off-by: Ziqi Chen <[e-mail]>
> Signed-off-by: Can Guo <[e-mail]>

Reveiwed-by: Bean Huo <[e-mail]>

Patch

diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index 0549b65f71ed..4da3e65c6735 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -277,6 +277,14 @@  static inline int ufshcd_mcq_vops_config_esi(struct ufs_hba *hba)
 	return -EOPNOTSUPP;
 }
 
+static inline int ufshcd_vops_freq_to_gear_speed(struct ufs_hba *hba, unsigned long freq)
+{
+	if (hba->vops && hba->vops->freq_to_gear_speed)
+		return hba->vops->freq_to_gear_speed(hba, freq);
+
+	return -EOPNOTSUPP;
+}
+
 extern const struct ufs_pm_lvl_states ufs_pm_lvl_states[];
 
 /**
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index f51d425696e7..cdb853f5b871 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -336,6 +336,7 @@  struct ufs_pwr_mode_info {
  * @get_outstanding_cqs: called to get outstanding completion queues
  * @config_esi: called to config Event Specific Interrupt
  * @config_scsi_dev: called to configure SCSI device parameters
+ * @freq_to_gear_speed: called to map clock frequency to the max supported gear speed
  */
 struct ufs_hba_variant_ops {
 	const char *name;
@@ -387,6 +388,7 @@  struct ufs_hba_variant_ops {
 				       unsigned long *ocqs);
 	int	(*config_esi)(struct ufs_hba *hba);
 	void	(*config_scsi_dev)(struct scsi_device *sdev);
+	int (*freq_to_gear_speed)(struct ufs_hba *hba, unsigned long freq);
 };
 
 /* clock gating state  */