Register optional operation-points-v2 table for ICE device
and aquire its minimum and maximum frequency during ICE
device probe.

Introduce clock scaling API qcom_ice_scale_clk which scale ICE
core clock based on the target frequency provided and if a valid
OPP-table is registered. Use flags (if provided) to decide on
the rounding of the clock freq against OPP-table. Incase no flags
are provided use default behaviour (CEIL incase of scale_up and FLOOR
incase of ~scale_up). Disable clock scaling if OPP-table is not
registered.

When an ICE-device specific OPP table is available, use the PM OPP
framework to manage frequency scaling and maintain proper power-domain
constraints.

Also, ensure to drop the votes in suspend to prevent power/thermal
retention. Subsequently restore the frequency in resume from
core_clk_freq which stores the last ICE core clock operating frequency.

Signed-off-by: Abhinaba Rakshit <abhinaba.rakshit@oss.qualcomm.com>
---
 drivers/soc/qcom/ice.c | 132 +++++++++++++++++++++++++++++++++++++++++++++++--
 include/soc/qcom/ice.h |   5 ++
 2 files changed, 134 insertions(+), 3 deletions(-)

diff --git a/drivers/soc/qcom/ice.c b/drivers/soc/qcom/ice.c
index b203bc685cadd21d6f96eb1799963a13db4b2b72..0bdc64db414a7028653c0f3327988b1554788fcf 100644
--- a/drivers/soc/qcom/ice.c
+++ b/drivers/soc/qcom/ice.c
@@ -16,6 +16,7 @@
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
+#include <linux/pm_opp.h>
 
 #include <linux/firmware/qcom/qcom_scm.h>
 
@@ -111,6 +112,10 @@ struct qcom_ice {
 	bool use_hwkm;
 	bool hwkm_init_complete;
 	u8 hwkm_version;
+	unsigned long max_freq;
+	unsigned long min_freq;
+	unsigned long core_clk_freq;
+	bool has_opp;
 };
 
 static bool qcom_ice_check_supported(struct qcom_ice *ice)
@@ -310,12 +315,17 @@ int qcom_ice_resume(struct qcom_ice *ice)
 	struct device *dev = ice->dev;
 	int err;
 
+	/* Restore the ICE core clk freq */
+	if (ice->has_opp && ice->core_clk_freq)
+		dev_pm_opp_set_rate(ice->dev, ice->core_clk_freq);
+
 	err = clk_prepare_enable(ice->core_clk);
 	if (err) {
 		dev_err(dev, "failed to enable core clock (%d)\n",
 			err);
 		return err;
 	}
+
 	qcom_ice_hwkm_init(ice);
 	return qcom_ice_wait_bist_status(ice);
 }
@@ -324,6 +334,11 @@ EXPORT_SYMBOL_GPL(qcom_ice_resume);
 int qcom_ice_suspend(struct qcom_ice *ice)
 {
 	clk_disable_unprepare(ice->core_clk);
+
+	/* Drop the clock votes while suspend */
+	if (ice->has_opp)
+		dev_pm_opp_set_rate(ice->dev, 0);
+
 	ice->hwkm_init_complete = false;
 
 	return 0;
@@ -549,10 +564,79 @@ int qcom_ice_import_key(struct qcom_ice *ice,
 }
 EXPORT_SYMBOL_GPL(qcom_ice_import_key);
 
+/**
+ * qcom_ice_scale_clk() - Scale ICE clock for DVFS-aware operations
+ * @ice: ICE driver data
+ * @target_freq: requested frequency in Hz
+ * @scale_up: If @flags is 0, choose ceil (true) or floor (false)
+ * @flags: Rounding policy (ICE_CLOCK_ROUND_*); overrides @scale_up
+ *
+ * Clamps @target_freq to the OPP range (min/max), selects an OPP per rounding
+ * policy, then applies it via dev_pm_opp_set_rate() (including voltage/PD
+ * changes).
+ *
+ * Return: 0 on success; -EOPNOTSUPP if no OPP table; or error from
+ *         dev_pm_opp_set_rate()/OPP lookup.
+ */
+int qcom_ice_scale_clk(struct qcom_ice *ice, unsigned long target_freq,
+		       bool scale_up, unsigned int flags)
+{
+	int ret;
+	unsigned long ice_freq = target_freq;
+	struct dev_pm_opp *opp;
+
+	if (!ice->has_opp)
+		return -EOPNOTSUPP;
+
+	/* Clamp the freq to max if target_freq is beyond supported frequencies */
+	if (ice->max_freq && target_freq >= ice->max_freq) {
+		ice_freq = ice->max_freq;
+		goto scale_clock;
+	}
+
+	/* Clamp the freq to min if target_freq is below supported frequencies */
+	if (ice->min_freq && target_freq <= ice->min_freq) {
+		ice_freq = ice->min_freq;
+		goto scale_clock;
+	}
+
+	switch (flags) {
+	case ICE_CLOCK_ROUND_CEIL:
+		opp = dev_pm_opp_find_freq_ceil_indexed(ice->dev, &ice_freq, 0);
+		break;
+	case ICE_CLOCK_ROUND_FLOOR:
+		opp = dev_pm_opp_find_freq_floor_indexed(ice->dev, &ice_freq, 0);
+		break;
+	default:
+		if (scale_up)
+			opp = dev_pm_opp_find_freq_ceil_indexed(ice->dev, &ice_freq, 0);
+		else
+			opp = dev_pm_opp_find_freq_floor_indexed(ice->dev, &ice_freq, 0);
+		break;
+	}
+
+	if (IS_ERR(opp))
+		return -EINVAL;
+	dev_pm_opp_put(opp);
+
+scale_clock:
+
+	ret = dev_pm_opp_set_rate(ice->dev, ice_freq);
+	if (!ret)
+		ice->core_clk_freq = ice_freq;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(qcom_ice_scale_clk);
+
 static struct qcom_ice *qcom_ice_create(struct device *dev,
-					void __iomem *base)
+					void __iomem *base,
+					bool is_legacy_binding)
 {
 	struct qcom_ice *engine;
+	struct dev_pm_opp *opp;
+	int err;
+	unsigned long rate;
 
 	if (!qcom_scm_is_available())
 		return ERR_PTR(-EPROBE_DEFER);
@@ -584,6 +668,48 @@ static struct qcom_ice *qcom_ice_create(struct device *dev,
 	if (IS_ERR(engine->core_clk))
 		return ERR_CAST(engine->core_clk);
 
+	/*
+	 * Register the OPP table only when ICE is described as a standalone
+	 * device node. Older platforms place ICE inside the storage controller
+	 * node, so they don't need an OPP table here, as they are handled in
+	 * storage controller.
+	 */
+	if (!is_legacy_binding) {
+		/* OPP table is optional */
+		err = devm_pm_opp_of_add_table(dev);
+		if (err && err != -ENODEV) {
+			dev_err(dev, "Invalid OPP table in Device tree\n");
+			return ERR_PTR(err);
+		}
+		engine->has_opp = (err == 0);
+
+		if (!engine->has_opp)
+			dev_info(dev, "ICE OPP table is not registered\n");
+	}
+
+	if (engine->has_opp) {
+		/* Find the ICE core clock min frequency */
+		rate = 0;
+		opp = dev_pm_opp_find_freq_ceil_indexed(dev, &rate, 0);
+		if (IS_ERR(opp)) {
+			dev_warn(dev, "Unable to find ICE core clock min freq\n");
+		} else {
+			engine->min_freq = rate;
+			dev_pm_opp_put(opp);
+		}
+
+		/* Find the ICE core clock max frequency */
+		rate = ULONG_MAX;
+		opp = dev_pm_opp_find_freq_floor_indexed(dev, &rate, 0);
+		if (IS_ERR(opp)) {
+			dev_warn(dev, "Unable to find ICE core clock max freq\n");
+		} else {
+			engine->max_freq = rate;
+			dev_pm_opp_put(opp);
+		}
+	}
+
+	engine->core_clk_freq = clk_get_rate(engine->core_clk);
 	if (!qcom_ice_check_supported(engine))
 		return ERR_PTR(-EOPNOTSUPP);
 
@@ -628,7 +754,7 @@ static struct qcom_ice *of_qcom_ice_get(struct device *dev)
 			return ERR_CAST(base);
 
 		/* create ICE instance using consumer dev */
-		return qcom_ice_create(&pdev->dev, base);
+		return qcom_ice_create(&pdev->dev, base, true);
 	}
 
 	/*
@@ -725,7 +851,7 @@ static int qcom_ice_probe(struct platform_device *pdev)
 		return PTR_ERR(base);
 	}
 
-	engine = qcom_ice_create(&pdev->dev, base);
+	engine = qcom_ice_create(&pdev->dev, base, false);
 	if (IS_ERR(engine))
 		return PTR_ERR(engine);
 
diff --git a/include/soc/qcom/ice.h b/include/soc/qcom/ice.h
index 4bee553f0a59d86ec6ce20f7c7b4bce28a706415..055edf3a704ff25a608a880cf9be35363f8a02d3 100644
--- a/include/soc/qcom/ice.h
+++ b/include/soc/qcom/ice.h
@@ -9,6 +9,9 @@
 #include <linux/blk-crypto.h>
 #include <linux/types.h>
 
+#define ICE_CLOCK_ROUND_CEIL	BIT(1)
+#define ICE_CLOCK_ROUND_FLOOR	BIT(2)
+
 struct qcom_ice;
 
 int qcom_ice_enable(struct qcom_ice *ice);
@@ -30,5 +33,7 @@ int qcom_ice_import_key(struct qcom_ice *ice,
 			const u8 *raw_key, size_t raw_key_size,
 			u8 lt_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE]);
 struct qcom_ice *devm_of_qcom_ice_get(struct device *dev);
+int qcom_ice_scale_clk(struct qcom_ice *ice, unsigned long target_freq,
+		       bool scale_up, unsigned int flags);
 
 #endif /* __QCOM_ICE_H__ */

-- 
2.34.1

On 2/11/26 10:47 AM, Abhinaba Rakshit wrote:
> Register optional operation-points-v2 table for ICE device
> and aquire its minimum and maximum frequency during ICE
> device probe.
> 
> Introduce clock scaling API qcom_ice_scale_clk which scale ICE
> core clock based on the target frequency provided and if a valid
> OPP-table is registered. Use flags (if provided) to decide on
> the rounding of the clock freq against OPP-table. Incase no flags
> are provided use default behaviour (CEIL incase of scale_up and FLOOR
> incase of ~scale_up). Disable clock scaling if OPP-table is not
> registered.
> 
> When an ICE-device specific OPP table is available, use the PM OPP
> framework to manage frequency scaling and maintain proper power-domain
> constraints.
> 
> Also, ensure to drop the votes in suspend to prevent power/thermal
> retention. Subsequently restore the frequency in resume from
> core_clk_freq which stores the last ICE core clock operating frequency.
> 
> Signed-off-by: Abhinaba Rakshit <abhinaba.rakshit@oss.qualcomm.com>
> ---

[...]

> +/**
> + * qcom_ice_scale_clk() - Scale ICE clock for DVFS-aware operations
> + * @ice: ICE driver data
> + * @target_freq: requested frequency in Hz
> + * @scale_up: If @flags is 0, choose ceil (true) or floor (false)
> + * @flags: Rounding policy (ICE_CLOCK_ROUND_*); overrides @scale_up
> + *
> + * Clamps @target_freq to the OPP range (min/max), selects an OPP per rounding
> + * policy, then applies it via dev_pm_opp_set_rate() (including voltage/PD
> + * changes).
> + *
> + * Return: 0 on success; -EOPNOTSUPP if no OPP table; or error from
> + *         dev_pm_opp_set_rate()/OPP lookup.
> + */
> +int qcom_ice_scale_clk(struct qcom_ice *ice, unsigned long target_freq,
> +		       bool scale_up, unsigned int flags)
> +{
> +	int ret;
> +	unsigned long ice_freq = target_freq;
> +	struct dev_pm_opp *opp;

Reverse-Christmas-tree ordering would be neat

> +
> +	if (!ice->has_opp)
> +		return -EOPNOTSUPP;
> +
> +	/* Clamp the freq to max if target_freq is beyond supported frequencies */
> +	if (ice->max_freq && target_freq >= ice->max_freq) {
> +		ice_freq = ice->max_freq;
> +		goto scale_clock;
> +	}
> +
> +	/* Clamp the freq to min if target_freq is below supported frequencies */
> +	if (ice->min_freq && target_freq <= ice->min_freq) {
> +		ice_freq = ice->min_freq;
> +		goto scale_clock;
> +	}

The OPP framework won't let you overclock the ICE if this is what these checks
are about. Plus the clk framework will perform rounding for you too

> +
> +	switch (flags) {

Are you going to use these flags? Currently they're dead code

> +	case ICE_CLOCK_ROUND_CEIL:
> +		opp = dev_pm_opp_find_freq_ceil_indexed(ice->dev, &ice_freq, 0);

You never use the index (hardcoded to 0)

> +		break;
> +	case ICE_CLOCK_ROUND_FLOOR:
> +		opp = dev_pm_opp_find_freq_floor_indexed(ice->dev, &ice_freq, 0);
> +		break;
> +	default:
> +		if (scale_up)
> +			opp = dev_pm_opp_find_freq_ceil_indexed(ice->dev, &ice_freq, 0);
> +		else
> +			opp = dev_pm_opp_find_freq_floor_indexed(ice->dev, &ice_freq, 0);

Is this distinction necessary?

Konrad