Re: [PATCH V2 2/2] cpufreq: dt: Refactor initialization to handle probe deferral properly

[Viresh Kumar <viresh.kumar@linaro.org>]

On 01-09-20, 10:57, Marek Szyprowski wrote:
> This patch landed in linux-next about a week ago. It introduces a 
> following warning on Samsung Exnyos3250 SoC:
> 
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 1000000000, volt: 1150000, enabled: 1. New: freq: 1000000000, volt: 
> 1150000, enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 900000000, volt: 1112500, enabled: 1. New: freq: 900000000, volt: 
> 1112500, enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 800000000, volt: 1075000, enabled: 1. New: freq: 800000000, volt: 
> 1075000, enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 700000000, volt: 1037500, enabled: 1. New: freq: 700000000, volt: 
> 1037500, enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 600000000, volt: 1000000, enabled: 1. New: freq: 600000000, volt: 
> 1000000, enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 500000000, volt: 962500, enabled: 1. New: freq: 500000000, volt: 962500, 
> enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 400000000, volt: 925000, enabled: 1. New: freq: 400000000, volt: 925000, 
> enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 300000000, volt: 887500, enabled: 1. New: freq: 300000000, volt: 887500, 
> enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 200000000, volt: 850000, enabled: 1. New: freq: 200000000, volt: 850000, 
> enabled: 1
> cpu cpu1: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 
> 100000000, volt: 850000, enabled: 1. New: freq: 100000000, volt: 850000, 
> enabled: 1
> 
> I've checked a bit and this is related to the fact that Exynos3250 SoC 
> use OPP-v1 table. Is this intentional? It is not a problem to convert it 
> to OPP-v2 and mark OPP table as shared, but this is a kind of a regression.

It took me 20 minutes for me to see "where has my patch gone" :(

I wrote a small patch for that to work without any issues, but not
sure how I missed or abandoned it. Anyway, here is the diff again and
I will send it out again once you confirm it fixes the issue. Can you
please also test your driver as a module with multiple insertion/removals ?

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index 5dac8bffd68c..e72753be7dc7 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -905,6 +905,16 @@ 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;
@@ -921,10 +931,6 @@ 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;

-- 
viresh