CPUFreq core doesn't control value of .driver_data and this field is completely driver specific. This can contain any value and not only indexes. For most of the drivers, which aren't using this field, its value is zero. So, printing this from core doesn't make any sense. Don't print it.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/cpufreq/freq_table.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c index 8e54f97..f002272 100644 --- a/drivers/cpufreq/freq_table.c +++ b/drivers/cpufreq/freq_table.c @@ -36,8 +36,7 @@ int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, && table[i].driver_data == CPUFREQ_BOOST_FREQ) continue;
- pr_debug("table entry %u: %u kHz, %u driver_data\n", - i, freq, table[i].driver_data); + pr_debug("table entry %u: %u kHz\n", i, freq); if (freq < min_freq) min_freq = freq; if (freq > max_freq) @@ -175,8 +174,8 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy, } else *index = optimal.driver_data;
- pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency, - table[*index].driver_data); + pr_debug("target index is %u, freq is:%u kHz\n", *index, + table[*index].frequency);
return 0; }
On 03/27/2014 03:37 PM, Viresh Kumar wrote:
CPUFreq core doesn't control value of .driver_data and this field is completely driver specific. This can contain any value and not only indexes. For most of the drivers, which aren't using this field, its value is zero. So, printing this from core doesn't make any sense. Don't print it.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Reviewed-by: Srivatsa S. Bhat srivatsa.bhat@linux.vnet.ibm.com
Regards, Srivatsa S. Bhat
drivers/cpufreq/freq_table.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c index 8e54f97..f002272 100644 --- a/drivers/cpufreq/freq_table.c +++ b/drivers/cpufreq/freq_table.c @@ -36,8 +36,7 @@ int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, && table[i].driver_data == CPUFREQ_BOOST_FREQ) continue;
pr_debug("table entry %u: %u kHz, %u driver_data\n",i, freq, table[i].driver_data);
pr_debug("table entry %u: %u kHz\n", i, freq);@@ -175,8 +174,8 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy, } else *index = optimal.driver_data;
- pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
table[*index].driver_data);
pr_debug("target index is %u, freq is:%u kHz\n", *index,
table[*index].frequency);return 0;
}
On Thu, Mar 27, 2014 at 03:37:22PM +0530, Viresh Kumar wrote:
CPUFreq core doesn't control value of .driver_data and this field is completely driver specific. This can contain any value and not only indexes. For most of the drivers, which aren't using this field, its value is zero. So, printing this from core doesn't make any sense. Don't print it.
So after this patch, driver_data is only going to be used by drivers which want an "unsigned int" value to be saved along with the frequency in the frequency_table and for those who want to overload its interpretation to indicate BOOST.
From the core's stand point, it is useful only for determining whether
a frequency is BOOST frequency or not.
So, wouldn't it be logical to allow drivers maintain their own driver data since the core is anyway not interested in it, and change this .driver_data to "flags" or some such which can indicate boost ?
-- Thanks and Regards gautham.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
drivers/cpufreq/freq_table.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c index 8e54f97..f002272 100644 --- a/drivers/cpufreq/freq_table.c +++ b/drivers/cpufreq/freq_table.c @@ -36,8 +36,7 @@ int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, && table[i].driver_data == CPUFREQ_BOOST_FREQ) continue;
pr_debug("table entry %u: %u kHz, %u driver_data\n",i, freq, table[i].driver_data);
pr_debug("table entry %u: %u kHz\n", i, freq);@@ -175,8 +174,8 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy, } else *index = optimal.driver_data;
- pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
table[*index].driver_data);
pr_debug("target index is %u, freq is:%u kHz\n", *index,
table[*index].frequency);return 0;
}
1.7.12.rc2.18.g61b472e
On 27 March 2014 16:18, Gautham R Shenoy ego@linux.vnet.ibm.com wrote:
So after this patch, driver_data is only going to be used by drivers which want an "unsigned int" value to be saved along with the frequency in the frequency_table and for those who want to overload its interpretation to indicate BOOST.
From the core's stand point, it is useful only for determining whether a frequency is BOOST frequency or not.
Yes.
So, wouldn't it be logical to allow drivers maintain their own driver data since the core is anyway not interested in it, and change this .driver_data to "flags" or some such which can indicate boost ?
We can add another field .flags in case Rafael doesn't accept the other proposal I sent for fixing BOOST issue.
But the point behind keeping .driver_data field here was: many drivers have some information attached to each frequency and they are closely bound to each other. And so it made more sense to keep them together. This is still used by many drivers and I wouldn't like them to maintain separate arrays for keeping this information. They are so much bound to the frequencies at the same index, that keeping them separately wouldn't be a good idea.
On Thu, Mar 27, 2014 at 04:29:37PM +0530, Viresh Kumar wrote:
On 27 March 2014 16:18, Gautham R Shenoy ego@linux.vnet.ibm.com wrote:
So after this patch, driver_data is only going to be used by drivers which want an "unsigned int" value to be saved along with the frequency in the frequency_table and for those who want to overload its interpretation to indicate BOOST.
From the core's stand point, it is useful only for determining whether a frequency is BOOST frequency or not.
Yes.
So, wouldn't it be logical to allow drivers maintain their own driver data since the core is anyway not interested in it, and change this .driver_data to "flags" or some such which can indicate boost ?
We can add another field .flags in case Rafael doesn't accept the other proposal I sent for fixing BOOST issue.
Even with that patch, the .driver_data won't be opaque. And that's not good. Because, while some driver might not be explicitly setting the value of .driver_data to 0xABABABAB, it might want to store the value obtained at runtime into this field. And it could so happen that at runtime this value is 0xABABABAB.
But the point behind keeping .driver_data field here was: many drivers have some information attached to each frequency and they are closely bound to each other. And so it made more sense to keep them together. This is still used by many drivers and I wouldn't like them to maintain separate arrays for keeping this information. They are so much bound to the frequencies at the same index, that keeping them separately wouldn't be a good idea.
I understand this part. However there might be more data than an "unsigned int" that the drivers would like to be bound at the same index. Voltage information, for instance.
-- Thanks and Regards gautham.
Hi Gautham,
On Thu, Mar 27, 2014 at 04:29:37PM +0530, Viresh Kumar wrote:
On 27 March 2014 16:18, Gautham R Shenoy ego@linux.vnet.ibm.com wrote:
So after this patch, driver_data is only going to be used by drivers which want an "unsigned int" value to be saved along with the frequency in the frequency_table and for those who want to overload its interpretation to indicate BOOST.
From the core's stand point, it is useful only for determining whether a frequency is BOOST frequency or not.
Yes.
So, wouldn't it be logical to allow drivers maintain their own driver data since the core is anyway not interested in it, and change this .driver_data to "flags" or some such which can indicate boost ?
We can add another field .flags in case Rafael doesn't accept the other proposal I sent for fixing BOOST issue.
Even with that patch, the .driver_data won't be opaque. And that's not good. Because, while some driver might not be explicitly setting the value of .driver_data to 0xABABABAB, it might want to store the value obtained at runtime into this field. And it could so happen that at runtime this value is 0xABABABAB.
The .driver_data initially stored the index of the freq_table. Even the name was ".index" not .driver_data. The "index" name was informative and reflected the purpose of the field. For this reason the BOOST marker was fitted there, since BOOST is somewhat extra state.
Then the name was chaged to .drviver_data. This name indicates that driver specific information can be stored there (in the uint32 format).
It would work if we stored there only flags (like it is now). However Gutham proposed idea to store there the voltage value - preferably stored as int.
For me it seems, like we are trying to mix arbitrary values and predefined flags in one variable. In my opinion we should split .driver_data field to two separate ones - namely .flags and .driver_data.
Another solution, but NOT recommended by me, would be to split this field to have 16 bits for flags (upper) and lower 16 bits for values.
But the point behind keeping .driver_data field here was: many drivers have some information attached to each frequency and they are closely bound to each other. And so it made more sense to keep them together. This is still used by many drivers and I wouldn't like them to maintain separate arrays for keeping this information. They are so much bound to the frequencies at the same index, that keeping them separately wouldn't be a good idea.
I understand this part. However there might be more data than an "unsigned int" that the drivers would like to be bound at the same index. Voltage information, for instance.
-- Thanks and Regards gautham.
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