PM / OPP: Minor cleanups

PATCH In review Viresh Kumar 2 participants 7 messages May 23, 2017

Subsystems (4)

Driver core Suspend to RAM Hibernation Power management core

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Viresh Kumar

author

2017-05-23 04:01 UTC #0 lore raw

v2 cover PM / OPP: Minor cleanups

Hi,

Here are few cleanup patches for the OPP core. The first two simplify the code that was written specifically due to the limitations that we had because of RCUs. We don't RCUs anymore and this can be simplified.

The last two take care of specific corner cases.

Rebased over pm/linux-next and tested on Exynos dual core board.

V1->V2:
- Some RBY from Stephen
- s/while/for/ for one of the loops
- Dropped a comment and fixed an error message
- opp-table marked as const in one of the place.

Viresh Kumar (4):
PM / OPP: Reorganize _generic_set_opp_regulator()
PM / OPP: Don't create copy of regulators unnecessarily PM / OPP: opp-microvolt is not optional if regulators are set PM / OPP: Don't create debugfs "supply-0" directory unnecessarily

 drivers/base/power/opp/core.c    | 87 +++++++++++++++++-----------------------
 drivers/base/power/opp/debugfs.c |  7 ++--
 drivers/base/power/opp/of.c      | 10 ++++-
 3 files changed, 48 insertions(+), 56 deletions(-)

Signature · 1 line

2.13.0.70.g6367777092d9

Viresh Kumar

author

2017-05-23 04:02 UTC #1 lore raw

PATCH v2 1/4 PM / OPP: Reorganize _generic_set_opp_regulator()

The code was overly complicated here because of the limitations that we had with RCUs (Couldn't use opp-table and OPPs outside RCU protected section and can't call sleep-able routines from within that). But that is long gone now.

Reorganize _generic_set_opp_regulator() in order to avoid using "struct dev_pm_set_opp_data" and copying data into it for the case where opp_table->set_opp is not set.

Signed-off-by Viresh Kumar <[email protected]>

Reviewed-by Stephen Boyd <[email protected]>

---
 drivers/base/power/opp/core.c | 73 ++++++++++++++++++++-----------------------
 1 file changed, 34 insertions(+), 39 deletions(-)

drivers/base/power/opp/core.c +34 ~~-39~~

index dae61720b314..c4590fc017ba 100644
@@ -543,17 +543,18 @@ _generic_set_opp_clk_only(struct device *dev, struct clk *clk,
 	return ret;
 }
 
-static int _generic_set_opp(struct dev_pm_set_opp_data *data)
+static int _generic_set_opp_regulator(const struct opp_table *opp_table,
+				      struct device *dev,
+				      unsigned long old_freq,
+				      unsigned long freq,
+				      struct dev_pm_opp_supply *old_supply,
+				      struct dev_pm_opp_supply *new_supply)
 {
-	struct dev_pm_opp_supply *old_supply = data->old_opp.supplies;
-	struct dev_pm_opp_supply *new_supply = data->new_opp.supplies;
-	unsigned long old_freq = data->old_opp.rate, freq = data->new_opp.rate;
-	struct regulator *reg = data->regulators[0];
-	struct device *dev= data->dev;
+	struct regulator *reg = opp_table->regulators[0];
 	int ret;
 
 	/* This function only supports single regulator per device */
-	if (WARN_ON(data->regulator_count > 1)) {
+	if (WARN_ON(opp_table->regulator_count > 1)) {
 		dev_err(dev, "multiple regulators are not supported\n");
 		return -EINVAL;
 	}

@@ -566,7 +567,7 @@ static int _generic_set_opp(struct dev_pm_set_opp_data *data)
 	}
 
 	/* Change frequency */
-	ret = _generic_set_opp_clk_only(dev, data->clk, old_freq, freq);
+	ret = _generic_set_opp_clk_only(dev, opp_table->clk, old_freq, freq);
 	if (ret)
 		goto restore_voltage;

@@ -580,12 +581,12 @@ static int _generic_set_opp(struct dev_pm_set_opp_data *data)
 	return 0;
 
 restore_freq:
-	if (_generic_set_opp_clk_only(dev, data->clk, freq, old_freq))
+	if (_generic_set_opp_clk_only(dev, opp_table->clk, freq, old_freq))
 		dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
 			__func__, old_freq);
 restore_voltage:
 	/* This shouldn't harm even if the voltages weren't updated earlier */
-	if (old_supply->u_volt)
+	if (old_supply)
 		_set_opp_voltage(dev, reg, old_supply);
 
 	return ret;

@@ -603,10 +604,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 {
 	struct opp_table *opp_table;
 	unsigned long freq, old_freq;
-	int (*set_opp)(struct dev_pm_set_opp_data *data);
 	struct dev_pm_opp *old_opp, *opp;
-	struct regulator **regulators;
-	struct dev_pm_set_opp_data *data;
 	struct clk *clk;
 	int ret, size;

@@ -661,38 +659,35 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 	dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n", __func__,
 		old_freq, freq);
 
-	regulators = opp_table->regulators;
-
 	/* Only frequency scaling */
-	if (!regulators) {
+	if (!opp_table->regulators) {
 		ret = _generic_set_opp_clk_only(dev, clk, old_freq, freq);
-		goto put_opps;
-	}
+	} else if (!opp_table->set_opp) {
+		ret = _generic_set_opp_regulator(opp_table, dev, old_freq, freq,
+						 IS_ERR(old_opp) ? NULL : old_opp->supplies,
+						 opp->supplies);
+	} else {
+		struct dev_pm_set_opp_data *data;
 
-	if (opp_table->set_opp)
-		set_opp = opp_table->set_opp;
-	else
-		set_opp = _generic_set_opp;
-
-	data = opp_table->set_opp_data;
-	data->regulators = regulators;
-	data->regulator_count = opp_table->regulator_count;
-	data->clk = clk;
-	data->dev = dev;
-
-	data->old_opp.rate = old_freq;
-	size = sizeof(*opp->supplies) * opp_table->regulator_count;
-	if (IS_ERR(old_opp))
-		memset(data->old_opp.supplies, 0, size);
-	else
-		memcpy(data->old_opp.supplies, old_opp->supplies, size);
+		data = opp_table->set_opp_data;
+		data->regulators = opp_table->regulators;
+		data->regulator_count = opp_table->regulator_count;
+		data->clk = clk;
+		data->dev = dev;
 
-	data->new_opp.rate = freq;
-	memcpy(data->new_opp.supplies, opp->supplies, size);
+		data->old_opp.rate = old_freq;
+		size = sizeof(*opp->supplies) * opp_table->regulator_count;
+		if (IS_ERR(old_opp))
+			memset(data->old_opp.supplies, 0, size);
+		else
+			memcpy(data->old_opp.supplies, old_opp->supplies, size);
 
-	ret = set_opp(data);
+		data->new_opp.rate = freq;
+		memcpy(data->new_opp.supplies, opp->supplies, size);
+
+		ret = opp_table->set_opp(data);
+	}
 
-put_opps:
 	dev_pm_opp_put(opp);
 put_old_opp:
 	if (!IS_ERR(old_opp))

Signature · 1 line

2.13.0.70.g6367777092d9

Viresh Kumar

author

2017-05-23 04:02 UTC #2 lore raw

PATCH v2 2/4 PM / OPP: Don't create copy of regulators unnecessarily

This code was required while the OPP core was managed with help of RCUs, but not anymore. Get rid of unnecessary alloc/memcpy operations.

Signed-off-by Viresh Kumar <[email protected]>

Reviewed-by Stephen Boyd <[email protected]>

---
 drivers/base/power/opp/core.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

drivers/base/power/opp/core.c +3 ~~-11~~

index c4590fc017ba..5ee7aadf0abf 100644
@@ -180,7 +180,7 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 {
 	struct opp_table *opp_table;
 	struct dev_pm_opp *opp;
-	struct regulator *reg, **regulators;
+	struct regulator *reg;
 	unsigned long latency_ns = 0;
 	int ret, i, count;
 	struct {

@@ -198,15 +198,9 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 	if (!count)
 		goto put_opp_table;
 
-	regulators = kmalloc_array(count, sizeof(*regulators), GFP_KERNEL);
-	if (!regulators)
-		goto put_opp_table;
-
 	uV = kmalloc_array(count, sizeof(*uV), GFP_KERNEL);
 	if (!uV)
-		goto free_regulators;
-
-	memcpy(regulators, opp_table->regulators, count * sizeof(*regulators));
+		goto put_opp_table;
 
 	mutex_lock(&opp_table->lock);

@@ -232,15 +226,13 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 	 * isn't freed, while we are executing this routine.
 	 */
 	for (i = 0; i < count; i++) {
-		reg = regulators[i];
+		reg = opp_table->regulators[i];
 		ret = regulator_set_voltage_time(reg, uV[i].min, uV[i].max);
 		if (ret > 0)
 			latency_ns += ret * 1000;
 	}
 
 	kfree(uV);
-free_regulators:
-	kfree(regulators);
 put_opp_table:
 	dev_pm_opp_put_opp_table(opp_table);

Signature · 1 line

2.13.0.70.g6367777092d9

Viresh Kumar

author

2017-05-23 04:02 UTC #3 lore raw

PATCH v2 3/4 PM / OPP: opp-microvolt is not optional if regulators are set

In reply to Viresh Kumar

If dev_pm_opp_set_regulators() is called for a device and its regulators are set in the OPP core, the OPP nodes for the device must contain the "opp-microvolt" property, otherwise there is something wrong and we better error out.

Signed-off-by Viresh Kumar <[email protected]>

---
 drivers/base/power/opp/of.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

drivers/base/power/opp/of.c +8 -2

index 779428676f63..57eec1ca0569 100644
@@ -131,8 +131,14 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 		prop = of_find_property(opp->np, name, NULL);
 
 		/* Missing property isn't a problem, but an invalid entry is */
-		if (!prop)
-			return 0;
+		if (!prop) {
+			if (!opp_table->regulator_count)
+				return 0;
+
+			dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
+				__func__);
+			return -EINVAL;
+		}
 	}
 
 	vcount = of_property_count_u32_elems(opp->np, name);

Signature · 1 line

2.13.0.70.g6367777092d9

Stephen Boyd

Reviewed-by on v2 3/4

2017-05-23 21:01 UTC #4 lore raw

Re: [PATCH V2 3/4] PM / OPP: opp-microvolt is not optional if regulators are set

Quoted 7 lines · Viresh Kumar

If dev_pm_opp_set_regulators() is called for a device and its regulators are set in the OPP core, the OPP nodes for the device must contain the "opp-microvolt" property, otherwise there is something wrong and we better error out.
Signed-off-by Viresh Kumar <[email protected]>
---

Reviewed-by Stephen Boyd <[email protected]>

Signature · 2 lines

Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

Viresh Kumar

author

2017-05-23 04:02 UTC #5 lore raw

PATCH v2 4/4 PM / OPP: Don't create debugfs "supply-0" directory unnecessarily

In reply to Viresh Kumar

We create "supply-0" debugfs directory even if the device doesn't do voltage scaling. That looks confusing, as if the regulator is found but we never managed to get voltage levels for it.

Avoid creating such a directory unnecessarily.

Signed-off-by Viresh Kumar <[email protected]>

---
 drivers/base/power/opp/debugfs.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

drivers/base/power/opp/debugfs.c +3 -4

index 95f433db4ac7..81cf120fcf43 100644
@@ -40,11 +40,10 @@ static bool opp_debug_create_supplies(struct dev_pm_opp *opp,
 				      struct dentry *pdentry)
 {
 	struct dentry *d;
-	int i = 0;
+	int i;
 	char *name;
 
-	/* Always create at least supply-0 directory */
-	do {
+	for (i = 0; i < opp_table->regulator_count; i++) {
 		name = kasprintf(GFP_KERNEL, "supply-%d", i);
 
 		/* Create per-opp directory */

@@ -70,7 +69,7 @@ static bool opp_debug_create_supplies(struct dev_pm_opp *opp,
 		if (!debugfs_create_ulong("u_amp", S_IRUGO, d,
 					  &opp->supplies[i].u_amp))
 			return false;
-	} while (++i < opp_table->regulator_count);
+	}
 
 	return true;
 }

Signature · 1 line

2.13.0.70.g6367777092d9

Stephen Boyd

Reviewed-by on v2 4/4

2017-05-23 21:02 UTC #6 lore raw

Re: [PATCH V2 4/4] PM / OPP: Don't create debugfs "supply-0" directory unnecessarily

Quoted 8 lines · Viresh Kumar

We create "supply-0" debugfs directory even if the device doesn't do voltage scaling. That looks confusing, as if the regulator is found but we never managed to get voltage levels for it.
Avoid creating such a directory unnecessarily.
Signed-off-by Viresh Kumar <[email protected]>
---

Reviewed-by Stephen Boyd <[email protected]>

Signature · 2 lines

Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project