Commit 394b949f authored by Subhash Jadavani's avatar Subhash Jadavani Committed by Martin K. Petersen
Browse files

scsi: ufs: Clean up ufshcd_scale_clks() and clock scaling error out path 

This change introduces a func ufshcd_set_clk_freq() to explicitly set clock
frequency so that it can be used in reset_and_restore path and in
ufshcd_scale_clks(). This change also cleans up the clock scaling error out
path.

[mkp: commit desc]

Link: https://lore.kernel.org/r/1585214742-5466-2-git-send-email-cang@codeaurora.org


Fixes: a3cd5ec5 ("scsi: ufs: add load based scaling of UFS gear")
Reviewed-by: default avatarBean Huo <beanhuo@micron.com>
Acked-by: default avatarAvri Altman <Avri.Altman@wdc.com>
Signed-off-by: default avatarSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: default avatarCan Guo <cang@codeaurora.org>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent d75e119e

drivers/scsi/ufs/ufshcd.c

+44 −21
Original line number Diff line number Diff line
@@ -868,28 +868,29 @@ static bool ufshcd_is_unipro_pa_params_tuning_req(struct ufs_hba *hba) 
		return false;

}



static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up)

/**

 * ufshcd_set_clk_freq - set UFS controller clock frequencies

 * @hba: per adapter instance

 * @scale_up: If True, set max possible frequency othewise set low frequency

 *

 * Returns 0 if successful

 * Returns < 0 for any other errors

 */

static int ufshcd_set_clk_freq(struct ufs_hba *hba, bool scale_up)

{

	int ret = 0;

	struct ufs_clk_info *clki;

	struct list_head *head = &hba->clk_list_head;

	ktime_t start = ktime_get();

	bool clk_state_changed = false;



	if (list_empty(head))

		goto out;



	ret = ufshcd_vops_clk_scale_notify(hba, scale_up, PRE_CHANGE);

	if (ret)

		return ret;



	list_for_each_entry(clki, head, list) {

		if (!IS_ERR_OR_NULL(clki->clk)) {

			if (scale_up && clki->max_freq) {

				if (clki->curr_freq == clki->max_freq)

					continue;



				clk_state_changed = true;

				ret = clk_set_rate(clki->clk, clki->max_freq);

				if (ret) {

					dev_err(hba->dev, "%s: %s clk set rate(%dHz) failed, %d\n",
@@ -908,7 +909,6 @@ static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up) 
				if (clki->curr_freq == clki->min_freq)

					continue;



				clk_state_changed = true;

				ret = clk_set_rate(clki->clk, clki->min_freq);

				if (ret) {

					dev_err(hba->dev, "%s: %s clk set rate(%dHz) failed, %d\n",
@@ -927,10 +927,36 @@ static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up) 
				clki->name, clk_get_rate(clki->clk));

	}



out:

	return ret;

}



/**

 * ufshcd_scale_clks - scale up or scale down UFS controller clocks

 * @hba: per adapter instance

 * @scale_up: True if scaling up and false if scaling down

 *

 * Returns 0 if successful

 * Returns < 0 for any other errors

 */

static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up)

{

	int ret = 0;

	ktime_t start = ktime_get();



	ret = ufshcd_vops_clk_scale_notify(hba, scale_up, PRE_CHANGE);

	if (ret)

		goto out;



	ret = ufshcd_set_clk_freq(hba, scale_up);

	if (ret)

		goto out;



	ret = ufshcd_vops_clk_scale_notify(hba, scale_up, POST_CHANGE);

	if (ret)

		ufshcd_set_clk_freq(hba, !scale_up);



out:

	if (clk_state_changed)

	trace_ufshcd_profile_clk_scaling(dev_name(hba->dev),

			(scale_up ? "up" : "down"),

			ktime_to_us(ktime_sub(ktime_get(), start)), ret);
@@ -1119,35 +1145,32 @@ static int ufshcd_devfreq_scale(struct ufs_hba *hba, bool scale_up) 


	ret = ufshcd_clock_scaling_prepare(hba);

	if (ret)

		return ret;

		goto out;



	/* scale down the gear before scaling down clocks */

	if (!scale_up) {

		ret = ufshcd_scale_gear(hba, false);

		if (ret)

			goto out;

			goto out_unprepare;

	}



	ret = ufshcd_scale_clks(hba, scale_up);

	if (ret) {

		if (!scale_up)

			ufshcd_scale_gear(hba, true);

		goto out;

		goto out_unprepare;

	}



	/* scale up the gear after scaling up clocks */

	if (scale_up) {

		ret = ufshcd_scale_gear(hba, true);

		if (ret) {

		if (ret)

			ufshcd_scale_clks(hba, false);

			goto out;

	}

	}



	ret = ufshcd_vops_clk_scale_notify(hba, scale_up, POST_CHANGE);



out:

out_unprepare:

	ufshcd_clock_scaling_unprepare(hba);

out:

	ufshcd_release(hba);

	return ret;

}
@@ -6292,7 +6315,7 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba *hba) 
	spin_unlock_irqrestore(hba->host->host_lock, flags);



	/* scale up clocks to max frequency before full reinitialization */

	ufshcd_scale_clks(hba, true);

	ufshcd_set_clk_freq(hba, true);



	err = ufshcd_hba_enable(hba);

	if (err)

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