[PATCH] opp: Handle multiple calls for same OPP table in _of_add_opp_table_v1()

[PATCH] opp: Handle multiple calls for same OPP table in _of_add_opp_table_v1()

[Viresh Kumar]

Until now for V1 OPP bindings we used to call
dev_pm_opp_of_cpumask_add_table() first and then
dev_pm_opp_set_sharing_cpus() in the cpufreq-dt driver.

A later patch will though update the cpufreq-dt driver to optimize the
code a bit and we will call dev_pm_opp_set_sharing_cpus() first followed
by dev_pm_opp_of_cpumask_add_table(), which doesn't work well today as
it tries to re parse the OPP entries. This should work nevertheless for
V1 bindings as the same works for V2 bindings.

Adapt the same approach from V2 bindings and fix this.

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/opp/of.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index d8b623cc015a..6fc56660fa52 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -886,6 +886,16 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 	const __be32 *val;
 	int nr, ret = 0;
 
+	mutex_lock(&opp_table->lock);
+	if (opp_table->parsed_static_opps) {
+		opp_table->parsed_static_opps++;
+		mutex_unlock(&opp_table->lock);
+		return 0;
+	}
+
+	opp_table->parsed_static_opps = 1;
+	mutex_unlock(&opp_table->lock);
+
 	prop = of_find_property(dev->of_node, "operating-points", NULL);
 	if (!prop)
 		return -ENODEV;
@@ -902,10 +912,6 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 		return -EINVAL;
 	}
 
-	mutex_lock(&opp_table->lock);
-	opp_table->parsed_static_opps = 1;
-	mutex_unlock(&opp_table->lock);
-
 	val = prop->value;
 	while (nr) {
 		unsigned long freq = be32_to_cpup(val++) * 1000;
-- 
2.25.0.rc1.19.g042ed3e048af

Re: [PATCH] opp: Handle multiple calls for same OPP table in _of_add_opp_table_v1()

[Viresh Kumar]

On 01-09-20, 15:57, Viresh Kumar wrote:
> Until now for V1 OPP bindings we used to call
> dev_pm_opp_of_cpumask_add_table() first and then
> dev_pm_opp_set_sharing_cpus() in the cpufreq-dt driver.
> 
> A later patch will though update the cpufreq-dt driver to optimize the
> code a bit and we will call dev_pm_opp_set_sharing_cpus() first followed
> by dev_pm_opp_of_cpumask_add_table(), which doesn't work well today as
> it tries to re parse the OPP entries. This should work nevertheless for
> V1 bindings as the same works for V2 bindings.
> 
> Adapt the same approach from V2 bindings and fix this.
> 
> Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  drivers/opp/of.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/opp/of.c b/drivers/opp/of.c
> index d8b623cc015a..6fc56660fa52 100644
> --- a/drivers/opp/of.c
> +++ b/drivers/opp/of.c
> @@ -886,6 +886,16 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
>  	const __be32 *val;
>  	int nr, ret = 0;
>  
> +	mutex_lock(&opp_table->lock);
> +	if (opp_table->parsed_static_opps) {
> +		opp_table->parsed_static_opps++;
> +		mutex_unlock(&opp_table->lock);
> +		return 0;
> +	}
> +
> +	opp_table->parsed_static_opps = 1;
> +	mutex_unlock(&opp_table->lock);
> +
>  	prop = of_find_property(dev->of_node, "operating-points", NULL);
>  	if (!prop)
>  		return -ENODEV;
> @@ -902,10 +912,6 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
>  		return -EINVAL;
>  	}
>  
> -	mutex_lock(&opp_table->lock);
> -	opp_table->parsed_static_opps = 1;
> -	mutex_unlock(&opp_table->lock);
> -
>  	val = prop->value;
>  	while (nr) {
>  		unsigned long freq = be32_to_cpup(val++) * 1000;

This wasn't enough. Merged this diff as well to this patch:

 drivers/opp/of.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index e72753be7dc7..aa829a569825 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -916,10 +916,14 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
        mutex_unlock(&opp_table->lock);
 
        prop = of_find_property(dev->of_node, "operating-points", NULL);
-       if (!prop)
-               return -ENODEV;
-       if (!prop->value)
-               return -ENODATA;
+       if (!prop) {
+               ret = -ENODEV;
+               goto remove_static_opp;
+       }
+       if (!prop->value) {
+               ret = -ENODATA;
+               goto remove_static_opp;
+       }
 
        /*
         * Each OPP is a set of tuples consisting of frequency and
@@ -928,7 +932,8 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
        nr = prop->length / sizeof(u32);
        if (nr % 2) {
                dev_err(dev, "%s: Invalid OPP table\n", __func__);
-               return -EINVAL;
+               ret = -EINVAL;
+               goto remove_static_opp;
        }
 
        val = prop->value;
@@ -940,12 +945,14 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
                if (ret) {
                        dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
                                __func__, freq, ret);
-                       _opp_remove_all_static(opp_table);
-                       return ret;
+                       goto remove_static_opp;
                }
                nr -= 2;
        }
 
+remove_static_opp:
+       _opp_remove_all_static(opp_table);
+
        return ret;
 }

-- 
viresh