diff mbox series

[v2,15/48] opp: Support set_opp() customization without requiring to use regulators

Message ID 20201217180638.22748-16-digetx@gmail.com
State New
Headers show
Series Introduce core voltage scaling for NVIDIA Tegra20/30 SoCs | expand

Commit Message

Dmitry Osipenko Dec. 17, 2020, 6:06 p.m. UTC
Support set_opp() customization without requiring to use regulators. This
is needed by drivers which want to use dev_pm_opp_set_rate() for changing
rates of a multiple clocks and don't need to touch regulator.

One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware
units which should be use to the same clock rate, meanwhile voltage
scaling is done using a power domain. In this case OPP table doesn't have
a regulator, causing a NULL dereference in _set_opp_custom().

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/opp/core.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

Comments

Viresh Kumar Dec. 23, 2020, 6:01 a.m. UTC | #1
On 17-12-20, 21:06, Dmitry Osipenko wrote:
> Support set_opp() customization without requiring to use regulators. This

> is needed by drivers which want to use dev_pm_opp_set_rate() for changing

> rates of a multiple clocks and don't need to touch regulator.

> 

> One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware

> units which should be use to the same clock rate, meanwhile voltage

> scaling is done using a power domain. In this case OPP table doesn't have

> a regulator, causing a NULL dereference in _set_opp_custom().

> 

> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>

> ---

>  drivers/opp/core.c | 16 ++++++++++++----

>  1 file changed, 12 insertions(+), 4 deletions(-)

> 

> diff --git a/drivers/opp/core.c b/drivers/opp/core.c

> index 3d02fe33630b..625dae7a5ecb 100644

> --- a/drivers/opp/core.c

> +++ b/drivers/opp/core.c

> @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table,

>  			   struct dev_pm_opp_supply *old_supply,

>  			   struct dev_pm_opp_supply *new_supply)

>  {

> -	struct dev_pm_set_opp_data *data;

> +	struct dev_pm_set_opp_data *data, tmp_data;

> +	unsigned int regulator_count;

>  	int size;

>  

> -	data = opp_table->set_opp_data;

> +	if (opp_table->set_opp_data) {

> +		data = opp_table->set_opp_data;

> +		regulator_count = opp_table->regulator_count;

> +	} else {

> +		data = &tmp_data;

> +		regulator_count = 0;

> +	}

> +


We should use the same structure, you can add some checks but not replace the
structure altogether.

>  	data->regulators = opp_table->regulators;

> -	data->regulator_count = opp_table->regulator_count;

> +	data->regulator_count = regulator_count;

>  	data->clk = opp_table->clk;

>  	data->dev = dev;

>  

>  	data->old_opp.rate = old_freq;

> -	size = sizeof(*old_supply) * opp_table->regulator_count;

> +	size = sizeof(*old_supply) * regulator_count;

>  	if (!old_supply)

>  		memset(data->old_opp.supplies, 0, size);

>  	else


-- 
viresh
Dmitry Osipenko Dec. 23, 2020, 8:38 p.m. UTC | #2
23.12.2020 09:01, Viresh Kumar пишет:
> On 17-12-20, 21:06, Dmitry Osipenko wrote:
>> Support set_opp() customization without requiring to use regulators. This
>> is needed by drivers which want to use dev_pm_opp_set_rate() for changing
>> rates of a multiple clocks and don't need to touch regulator.
>>
>> One example is NVIDIA Tegra30/114 SoCs which have two sibling 3D hardware
>> units which should be use to the same clock rate, meanwhile voltage
>> scaling is done using a power domain. In this case OPP table doesn't have
>> a regulator, causing a NULL dereference in _set_opp_custom().
>>
>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
>> ---
>>  drivers/opp/core.c | 16 ++++++++++++----
>>  1 file changed, 12 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
>> index 3d02fe33630b..625dae7a5ecb 100644
>> --- a/drivers/opp/core.c
>> +++ b/drivers/opp/core.c
>> @@ -828,17 +828,25 @@ static int _set_opp_custom(const struct opp_table *opp_table,
>>  			   struct dev_pm_opp_supply *old_supply,
>>  			   struct dev_pm_opp_supply *new_supply)
>>  {
>> -	struct dev_pm_set_opp_data *data;
>> +	struct dev_pm_set_opp_data *data, tmp_data;
>> +	unsigned int regulator_count;
>>  	int size;
>>  
>> -	data = opp_table->set_opp_data;
>> +	if (opp_table->set_opp_data) {
>> +		data = opp_table->set_opp_data;
>> +		regulator_count = opp_table->regulator_count;
>> +	} else {
>> +		data = &tmp_data;
>> +		regulator_count = 0;
>> +	}
>> +
> 
> We should use the same structure, you can add some checks but not replace the
> structure altogether.

Well, there is no "same structure", the opp_table->set_opp_data is NULL
there.

I can re-write it like this if it looks better to you:

static int _set_opp_custom(...)
{
	struct dev_pm_set_opp_data *data;
	unsigned int regulator_count;
	int size;

+	if (!opp_table->set_opp_data) {
+		struct dev_pm_set_opp_data freq_data = {};
+
+		freq_data.dev = dev;
+		freq_data.clk = opp_table->clk;
+		freq_data.new_opp.rate = freq;
+		freq_data.old_opp.rate = old_freq;
+
+		return opp_table->set_opp(&freq_data);
+	}
Viresh Kumar Dec. 24, 2020, 4:10 a.m. UTC | #3
On 23-12-20, 23:38, Dmitry Osipenko wrote:
> Well, there is no "same structure", the opp_table->set_opp_data is NULL

> there.


Right, I saw that yesterday. What I meant was that we need to start allocating
the structure for this case now.

-- 
viresh
Dmitry Osipenko Dec. 24, 2020, 12:16 p.m. UTC | #4
24.12.2020 07:10, Viresh Kumar пишет:
> On 23-12-20, 23:38, Dmitry Osipenko wrote:

>> Well, there is no "same structure", the opp_table->set_opp_data is NULL

>> there.

> 

> Right, I saw that yesterday. What I meant was that we need to start allocating

> the structure for this case now.

> 


Okay, that will be a bit bigger change than this v2. I'll try it
implement yours suggestion in the next revision, thanks.
diff mbox series

Patch

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 3d02fe33630b..625dae7a5ecb 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -828,17 +828,25 @@  static int _set_opp_custom(const struct opp_table *opp_table,
 			   struct dev_pm_opp_supply *old_supply,
 			   struct dev_pm_opp_supply *new_supply)
 {
-	struct dev_pm_set_opp_data *data;
+	struct dev_pm_set_opp_data *data, tmp_data;
+	unsigned int regulator_count;
 	int size;
 
-	data = opp_table->set_opp_data;
+	if (opp_table->set_opp_data) {
+		data = opp_table->set_opp_data;
+		regulator_count = opp_table->regulator_count;
+	} else {
+		data = &tmp_data;
+		regulator_count = 0;
+	}
+
 	data->regulators = opp_table->regulators;
-	data->regulator_count = opp_table->regulator_count;
+	data->regulator_count = regulator_count;
 	data->clk = opp_table->clk;
 	data->dev = dev;
 
 	data->old_opp.rate = old_freq;
-	size = sizeof(*old_supply) * opp_table->regulator_count;
+	size = sizeof(*old_supply) * regulator_count;
 	if (!old_supply)
 		memset(data->old_opp.supplies, 0, size);
 	else