[PATCH] cpufreq: add frequency table to at32ap driver

[PATCH] cpufreq: add frequency table to at32ap driver

[Hans-Christian Egtvedt]

This patch adds a dynamically calculated frequency table to the at32ap driver.
In short the architecture can scale in power of two between a maximum and
minimum frequency. Min, max, and the steps in between are added to the table.

Signed-off-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
---
 drivers/cpufreq/at32ap-cpufreq.c | 47 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
index 6544887..dbf3f3d 100644
--- a/drivers/cpufreq/at32ap-cpufreq.c
+++ b/drivers/cpufreq/at32ap-cpufreq.c
@@ -19,8 +19,10 @@
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/export.h>
+#include <linux/slab.h>
 
 static struct clk *cpuclk;
+static struct cpufreq_frequency_table *freq_table;
 
 static int at32_verify_speed(struct cpufreq_policy *policy)
 {
@@ -85,13 +87,19 @@ static int at32_set_target(struct cpufreq_policy *policy,
 
 static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy)
 {
+	unsigned int frequency;
+	int retval;
+	int steps;
+	int i;
+
 	if (policy->cpu != 0)
 		return -EINVAL;
 
 	cpuclk = clk_get(NULL, "cpu");
 	if (IS_ERR(cpuclk)) {
 		pr_debug("cpufreq: could not get CPU clk\n");
-		return PTR_ERR(cpuclk);
+		retval = PTR_ERR(cpuclk);
+		goto out_err;
 	}
 
 	policy->cpuinfo.min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000;
@@ -101,9 +109,46 @@ static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy)
 	policy->min = policy->cpuinfo.min_freq;
 	policy->max = policy->cpuinfo.max_freq;
 
+	/*
+	 * AVR32 CPU frequency rate scales in power of two between maximum and
+	 * minimum, also add space for the table end marker.
+	 *
+	 * Further validate that the frequency is usable, and append it to the
+	 * frequency table.
+	 */
+	steps = fls(policy->cpuinfo.max_freq / policy->cpuinfo.min_freq) + 1;
+	freq_table = kzalloc(steps * sizeof(struct cpufreq_frequency_table),
+			GFP_KERNEL);
+	if (!freq_table) {
+		retval = -ENOMEM;
+		goto out_err_put_clk;
+	}
+
+	frequency = policy->cpuinfo.max_freq;
+	for (i = 0; i < (steps - 1); i++) {
+		unsigned int rate = clk_round_rate(cpuclk, frequency * 1000);
+		rate /= 1000;
+		if (rate != frequency)
+			freq_table[i].frequency = CPUFREQ_ENTRY_INVALID;
+		else
+			freq_table[i].frequency = frequency;
+		frequency /= 2;
+	}
+	freq_table[steps - 1].frequency = CPUFREQ_TABLE_END;
+
+	retval = cpufreq_frequency_table_cpuinfo(policy, freq_table);
+	if (retval)
+		goto out_err_kfree;
+
 	printk("cpufreq: AT32AP CPU frequency driver\n");
 
 	return 0;
+out_err_kfree:
+	kfree(freq_table);
+out_err_put_clk:
+	clk_put(cpuclk);
+out_err:
+	return retval;
 }
 
 static struct cpufreq_driver at32_driver = {
-- 
1.8.1.2

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Viresh Kumar]

On 13 August 2013 00:40, Hans-Christian Egtvedt <egtvedt@samfundet.no> wrote:
> This patch adds a dynamically calculated frequency table to the at32ap driver.
> In short the architecture can scale in power of two between a maximum and
> minimum frequency. Min, max, and the steps in between are added to the table.
>
> Signed-off-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
> ---
>  drivers/cpufreq/at32ap-cpufreq.c | 47 +++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 46 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
> index 6544887..dbf3f3d 100644
> --- a/drivers/cpufreq/at32ap-cpufreq.c
> +++ b/drivers/cpufreq/at32ap-cpufreq.c
> @@ -19,8 +19,10 @@
>  #include <linux/clk.h>
>  #include <linux/err.h>
>  #include <linux/export.h>
> +#include <linux/slab.h>
>
>  static struct clk *cpuclk;
> +static struct cpufreq_frequency_table *freq_table;
>
>  static int at32_verify_speed(struct cpufreq_policy *policy)
>  {
> @@ -85,13 +87,19 @@ static int at32_set_target(struct cpufreq_policy *policy,
>
>  static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy)
>  {
> +       unsigned int frequency;
> +       int retval;
> +       int steps;
> +       int i;
> +
>         if (policy->cpu != 0)
>                 return -EINVAL;
>
>         cpuclk = clk_get(NULL, "cpu");
>         if (IS_ERR(cpuclk)) {
>                 pr_debug("cpufreq: could not get CPU clk\n");
> -               return PTR_ERR(cpuclk);
> +               retval = PTR_ERR(cpuclk);
> +               goto out_err;
>         }
>
>         policy->cpuinfo.min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000;
> @@ -101,9 +109,46 @@ static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy)
>         policy->min = policy->cpuinfo.min_freq;
>         policy->max = policy->cpuinfo.max_freq;
>
> +       /*
> +        * AVR32 CPU frequency rate scales in power of two between maximum and
> +        * minimum, also add space for the table end marker.
> +        *
> +        * Further validate that the frequency is usable, and append it to the
> +        * frequency table.
> +        */
> +       steps = fls(policy->cpuinfo.max_freq / policy->cpuinfo.min_freq) + 1;
> +       freq_table = kzalloc(steps * sizeof(struct cpufreq_frequency_table),
> +                       GFP_KERNEL);
> +       if (!freq_table) {
> +               retval = -ENOMEM;
> +               goto out_err_put_clk;
> +       }
> +
> +       frequency = policy->cpuinfo.max_freq;
> +       for (i = 0; i < (steps - 1); i++) {
> +               unsigned int rate = clk_round_rate(cpuclk, frequency * 1000);
> +               rate /= 1000;
> +               if (rate != frequency)
> +                       freq_table[i].frequency = CPUFREQ_ENTRY_INVALID;
> +               else
> +                       freq_table[i].frequency = frequency;
> +               frequency /= 2;
> +       }
> +       freq_table[steps - 1].frequency = CPUFREQ_TABLE_END;
> +
> +       retval = cpufreq_frequency_table_cpuinfo(policy, freq_table);
> +       if (retval)
> +               goto out_err_kfree;
> +
>         printk("cpufreq: AT32AP CPU frequency driver\n");
>
>         return 0;
> +out_err_kfree:
> +       kfree(freq_table);
> +out_err_put_clk:
> +       clk_put(cpuclk);
> +out_err:
> +       return retval;
>  }
>
>  static struct cpufreq_driver at32_driver = {

Thanks for your patch, I have folded below patch with your patch while
applying..

diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
index eaac7cb..c586d3e 100644
--- a/drivers/cpufreq/at32ap-cpufreq.c
+++ b/drivers/cpufreq/at32ap-cpufreq.c
@@ -87,10 +87,8 @@ static int at32_set_target(struct cpufreq_policy *policy,

 static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy)
 {
-       unsigned int frequency;
-       int retval;
-       int steps;
-       int i;
+       unsigned int frequency, rate;
+       int retval, steps, i;

        if (policy->cpu != 0)
                return -EINVAL;
@@ -126,20 +124,23 @@ static int __init
at32_cpufreq_driver_init(struct cpufreq_policy *policy)

        frequency = policy->cpuinfo.max_freq;
        for (i = 0; i < (steps - 1); i++) {
-               unsigned int rate = clk_round_rate(cpuclk, frequency * 1000);
-               rate /= 1000;
+               rate = clk_round_rate(cpuclk, frequency * 1000) / 1000;
+
                if (rate != frequency)
                        freq_table[i].frequency = CPUFREQ_ENTRY_INVALID;
                else
                        freq_table[i].frequency = frequency;
+
                frequency /= 2;
        }
+
        freq_table[steps - 1].frequency = CPUFREQ_TABLE_END;

        retval = cpufreq_frequency_table_cpuinfo(policy, freq_table);
        if (retval)
                goto out_err_kfree;

+       cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
        printk("cpufreq: AT32AP CPU frequency driver\n");

        return 0;

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Viresh Kumar]

On 13 August 2013 10:38, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> Thanks for your patch, I have folded below patch with your patch while
> applying..

And actually this too, otherwise I need to do this separately in another
patch..

diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
index c586d3e..1d19fa5 100644
--- a/drivers/cpufreq/at32ap-cpufreq.c
+++ b/drivers/cpufreq/at32ap-cpufreq.c
@@ -136,15 +136,12 @@ static int __init
at32_cpufreq_driver_init(struct cpufreq_policy *policy)

        freq_table[steps - 1].frequency = CPUFREQ_TABLE_END;

-       retval = cpufreq_frequency_table_cpuinfo(policy, freq_table);
-       if (retval)
-               goto out_err_kfree;
-
-       cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
-       printk("cpufreq: AT32AP CPU frequency driver\n");
+       retval = cpufreq_table_validate_and_show(policy, freq_table);
+       if (!retval) {
+               printk("cpufreq: AT32AP CPU frequency driver\n");
+               return 0;
+       }

-       return 0;
-out_err_kfree:
        kfree(freq_table);
 out_err_put_clk:
        clk_put(cpuclk);

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Hans-Christian Egtvedt]

Around Tue 13 Aug 2013 10:38:14 +0530 or thereabout, Viresh Kumar wrote:
> On 13 August 2013 00:40, Hans-Christian Egtvedt <egtvedt@samfundet.no> wrote:
>> This patch adds a dynamically calculated frequency table to the at32ap driver.
>> In short the architecture can scale in power of two between a maximum and
>> minimum frequency. Min, max, and the steps in between are added to the table.
>>
>> Signed-off-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
>> ---
>>  drivers/cpufreq/at32ap-cpufreq.c | 47 +++++++++++++++++++++++++++++++++++++++-
>>  1 file changed, 46 insertions(+), 1 deletion(-)

<snipp diff>

> Thanks for your patch, I have folded below patch with your patch while
> applying..
> 
> diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
> index eaac7cb..c586d3e 100644
> --- a/drivers/cpufreq/at32ap-cpufreq.c
> +++ b/drivers/cpufreq/at32ap-cpufreq.c
> @@ -87,10 +87,8 @@ static int at32_set_target(struct cpufreq_policy *policy,
> 
>  static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy)
>  {
> -       unsigned int frequency;
> -       int retval;
> -       int steps;
> -       int i;
> +       unsigned int frequency, rate;
> +       int retval, steps, i;
> 
>         if (policy->cpu != 0)
>                 return -EINVAL;
> @@ -126,20 +124,23 @@ static int __init
> at32_cpufreq_driver_init(struct cpufreq_policy *policy)
> 
>         frequency = policy->cpuinfo.max_freq;
>         for (i = 0; i < (steps - 1); i++) {
> -               unsigned int rate = clk_round_rate(cpuclk, frequency * 1000);
> -               rate /= 1000;
> +               rate = clk_round_rate(cpuclk, frequency * 1000) / 1000;
> +
>                 if (rate != frequency)
>                         freq_table[i].frequency = CPUFREQ_ENTRY_INVALID;
>                 else
>                         freq_table[i].frequency = frequency;
> +
>                 frequency /= 2;
>         }
> +
>         freq_table[steps - 1].frequency = CPUFREQ_TABLE_END;
> 
>         retval = cpufreq_frequency_table_cpuinfo(policy, freq_table);
>         if (retval)
>                 goto out_err_kfree;
> 
> +       cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
>         printk("cpufreq: AT32AP CPU frequency driver\n");
> 
>         return 0;
> 

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>

-- 
mvh
Hans-Christian Egtvedt

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Hans-Christian Egtvedt]

Around Tue 13 Aug 2013 10:41:39 +0530 or thereabout, Viresh Kumar wrote:
> On 13 August 2013 10:38, Viresh Kumar <viresh.kumar@linaro.org> wrote:
>> Thanks for your patch, I have folded below patch with your patch while
>> applying..
> 
> And actually this too, otherwise I need to do this separately in another
> patch..
> 
> diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
> index c586d3e..1d19fa5 100644
> --- a/drivers/cpufreq/at32ap-cpufreq.c
> +++ b/drivers/cpufreq/at32ap-cpufreq.c
> @@ -136,15 +136,12 @@ static int __init
> at32_cpufreq_driver_init(struct cpufreq_policy *policy)
> 
>         freq_table[steps - 1].frequency = CPUFREQ_TABLE_END;
> 
> -       retval = cpufreq_frequency_table_cpuinfo(policy, freq_table);
> -       if (retval)
> -               goto out_err_kfree;
> -
> -       cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
> -       printk("cpufreq: AT32AP CPU frequency driver\n");
> +       retval = cpufreq_table_validate_and_show(policy, freq_table);
> +       if (!retval) {
> +               printk("cpufreq: AT32AP CPU frequency driver\n");
> +               return 0;
> +       }
> 
> -       return 0;
> -out_err_kfree:
>         kfree(freq_table);
>  out_err_put_clk:
>         clk_put(cpuclk);

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>

Thanks for cleaning up (-:

-- 
mvh
Hans-Christian Egtvedt

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Viresh Kumar]

On 13 August 2013 12:22, Hans-Christian Egtvedt <egtvedt@samfundet.no> wrote:
> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
>
> Thanks for cleaning up (-:

No problem..

Actually there is more to it.. We have got a freq table but neither .verify()
nor .target() uses it :) and so we need to fix those two also to fix it up..

.verify() looks to be pretty straight forward and so can be replaced by
the generic routine I wrote for that..

But .target() does some calculations which aren't very straight forward
to replace..

I believe I can remove all below code and simply get the frequency
as suggested by cpufreq-core ??

	/* Convert target_freq from kHz to Hz */
	freq = clk_round_rate(cpuclk, target_freq * 1000);

	/* Check if policy->min <= new_freq <= policy->max */
	if(freq < (policy->min * 1000) || freq > (policy->max * 1000))
		return -EINVAL;

	pr_debug("cpufreq: requested frequency %u Hz\n", target_freq * 1000);

	freqs.new = (freq + 500) / 1000;
	freqs.flags = 0;

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Hans-Christian Egtvedt]

Around Tue 13 Aug 2013 12:28:04 +0530 or thereabout, Viresh Kumar wrote:
> On 13 August 2013 12:22, Hans-Christian Egtvedt <egtvedt@samfundet.no> wrote:
>> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
>>
>> Thanks for cleaning up (-:
> 
> No problem..
> 
> Actually there is more to it.. We have got a freq table but neither .verify()
> nor .target() uses it :) and so we need to fix those two also to fix it up..
> 
> .verify() looks to be pretty straight forward and so can be replaced by
> the generic routine I wrote for that..

I though you already had a patch to swap verify, hence the need to cleanup
the cpufreq driver first to provide a frequency table?

> But .target() does some calculations which aren't very straight forward
> to replace..
> 
> I believe I can remove all below code and simply get the frequency
> as suggested by cpufreq-core ??
> 
> 	/* Convert target_freq from kHz to Hz */
> 	freq = clk_round_rate(cpuclk, target_freq * 1000);
> 
> 	/* Check if policy->min <= new_freq <= policy->max */
> 	if(freq < (policy->min * 1000) || freq > (policy->max * 1000))
> 		return -EINVAL;

This sanity checks that the frequency the system clock can generate is within
the policy limits. It is initially feed the target_freq frequency.

These values are already calculated during init and added to the table, so
one shouldn't need to perform the clk_round_rate() call anymore.

> 	pr_debug("cpufreq: requested frequency %u Hz\n", target_freq * 1000);
> 
> 	freqs.new = (freq + 500) / 1000;
> 	freqs.flags = 0;

I don't know the details of how the cpufreq-core suggests frequencies. If it
looks up in the frequency table, then we don't need this sanity check in
.target().

-- 
mvh
Hans-Christian Egtvedt

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Viresh Kumar]

On 13 August 2013 14:36, Hans-Christian Egtvedt <egtvedt@samfundet.no> wrote:
> Around Tue 13 Aug 2013 12:28:04 +0530 or thereabout, Viresh Kumar wrote:

>> .verify() looks to be pretty straight forward and so can be replaced by
>> the generic routine I wrote for that..
>
> I though you already had a patch to swap verify, hence the need to cleanup
> the cpufreq driver first to provide a frequency table?

Yes, that's what.. That generic routine can be used instead of your .verify()..

>> But .target() does some calculations which aren't very straight forward
>> to replace..
>>
>> I believe I can remove all below code and simply get the frequency
>> as suggested by cpufreq-core ??
>>
>>       /* Convert target_freq from kHz to Hz */
>>       freq = clk_round_rate(cpuclk, target_freq * 1000);
>>
>>       /* Check if policy->min <= new_freq <= policy->max */
>>       if(freq < (policy->min * 1000) || freq > (policy->max * 1000))
>>               return -EINVAL;
>
> This sanity checks that the frequency the system clock can generate is within
> the policy limits. It is initially feed the target_freq frequency.

This is already done in core.

> These values are already calculated during init and added to the table, so
> one shouldn't need to perform the clk_round_rate() call anymore.

good.

>>       pr_debug("cpufreq: requested frequency %u Hz\n", target_freq * 1000);
>>
>>       freqs.new = (freq + 500) / 1000;
>>       freqs.flags = 0;
>
> I don't know the details of how the cpufreq-core suggests frequencies. If it
> looks up in the frequency table, then we don't need this sanity check in
> .target().

Yes, it just picks the best match from freq table, though here is the actual
implementation..

https://lkml.org/lkml/2013/8/12/404

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Viresh Kumar]

On 13 August 2013 14:39, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> Yes, that's what.. That generic routine can be used instead of your .verify()..

So here is a patch for that which I will include in my original series. It uses
functions from this patch:

http://www.kernelhub.org/?msg=309940&p=2

-----------x-------------------x---------------------

commit e02892f73f8f669b265310e51a677c7253e32389
Author: Viresh Kumar <viresh.kumar@linaro.org>
Date:   Fri Aug 9 12:05:56 2013 +0530

    cpufreq: at32ap: Use generic cpufreq routines

    Most of the CPUFreq drivers do similar things in .exit() and
.verify() routines
    and .attr. So its better if we have generic routines for them
which can be used
    by cpufreq drivers then.

    This patch uses these generic routines for this driver.

    Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
    Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/cpufreq/at32ap-cpufreq.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c
index 1d19fa5..788f7e7 100644
--- a/drivers/cpufreq/at32ap-cpufreq.c
+++ b/drivers/cpufreq/at32ap-cpufreq.c
@@ -24,16 +24,6 @@
 static struct clk *cpuclk;
 static struct cpufreq_frequency_table *freq_table;

-static int at32_verify_speed(struct cpufreq_policy *policy)
-{
-       if (policy->cpu != 0)
-               return -EINVAL;
-
-       cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
-                       policy->cpuinfo.max_freq);
-       return 0;
-}
-
 static unsigned int at32_get_speed(unsigned int cpu)
 {
        /* No SMP support */
@@ -152,7 +142,7 @@ out_err:
 static struct cpufreq_driver at32_driver = {
        .name           = "at32ap",
        .init           = at32_cpufreq_driver_init,
-       .verify         = at32_verify_speed,
+       .verify         = cpufreq_generic_frequency_table_verify,
        .target         = at32_set_target,
        .get            = at32_get_speed,
        .flags          = CPUFREQ_STICKY,

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Hans-Christian Egtvedt]

Around Tue 13 Aug 2013 19:00:22 +0530 or thereabout, Viresh Kumar wrote:
> On 13 August 2013 14:39, Viresh Kumar <viresh.kumar@linaro.org> wrote:
>> Yes, that's what.. That generic routine can be used instead of your .verify()..
> 
> So here is a patch for that which I will include in my original series. It uses
> functions from this patch:
> 
> http://www.kernelhub.org/?msg=309940&p=2

Great. Is there anything left for the at32ap cpufreq driver?

> -----------x-------------------x---------------------
> 
> commit e02892f73f8f669b265310e51a677c7253e32389
> Author: Viresh Kumar <viresh.kumar@linaro.org>
> Date:   Fri Aug 9 12:05:56 2013 +0530
> 
>     cpufreq: at32ap: Use generic cpufreq routines
> 
>     Most of the CPUFreq drivers do similar things in .exit() and
> .verify() routines
>     and .attr. So its better if we have generic routines for them
> which can be used
>     by cpufreq drivers then.
> 
>     This patch uses these generic routines for this driver.
> 
>     Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
>     Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>

> ---
>  drivers/cpufreq/at32ap-cpufreq.c | 12 +-----------
>  1 file changed, 1 insertion(+), 11 deletions(-)

<snipp diff>

-- 
mvh
Hans-Christian Egtvedt

Re: [PATCH] cpufreq: add frequency table to at32ap driver

[Viresh Kumar]

On 14 August 2013 11:37, Hans-Christian Egtvedt <egtvedt@samfundet.no> wrote:
> Around Tue 13 Aug 2013 19:00:22 +0530 or thereabout, Viresh Kumar wrote:
>> On 13 August 2013 14:39, Viresh Kumar <viresh.kumar@linaro.org> wrote:
>>> Yes, that's what.. That generic routine can be used instead of your .verify()..
>>
>> So here is a patch for that which I will include in my original series. It uses
>> functions from this patch:
>>
>> http://www.kernelhub.org/?msg=309940&p=2
>
> Great. Is there anything left for the at32ap cpufreq driver?

You are cc'd for one more patch which simplifies target()...
Other than that nothing else for now.. But more will come
soon :)

I am running a cpufreq cleanup drive :) ... That may end only once I have
reduced code redundancy to the lowest possible level :)