Re: [PATCH 8/8] cpufreq: db8500: Use armss clk to update frequency

* Re: [PATCH 8/8] cpufreq: db8500: Use armss clk to update frequency
       [not found] ` <1349869349-8070-9-git-send-email-ulf.hansson@stericsson.com>
@ 2012-10-26  8:10   ` Ulf Hansson
  2012-10-26 11:20     ` Rafael J. Wysocki
  0 siblings, 1 reply; 8+ messages in thread
From: Ulf Hansson @ 2012-10-26  8:10 UTC (permalink / raw)
  To: Rafael J. Wysocki
  Cc: linux-arm-kernel, Mike Turquette, Mike Turquette, Samuel Ortiz,
	cpufreq, linux-pm, Linus Walleij, Lee Jones, Philippe Begnic,
	Rickard Andersson, Jonas Aberg, Vincent Guittot

On 10 October 2012 13:42, Ulf Hansson <ulf.hansson@stericsson.com> wrote:
> From: Ulf Hansson <ulf.hansson@linaro.org>
>
> Using the armss clk to update the frequency makes the driver no more
> directly dependant on the prmcu API.
>
> Cc: Rafael J. Wysocki <rjw@sisk.pl>
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/cpufreq/db8500-cpufreq.c |   24 ++++++++++++++++--------
>  1 file changed, 16 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/cpufreq/db8500-cpufreq.c b/drivers/cpufreq/db8500-cpufreq.c
> index dea9a49..4f154bc 100644
> --- a/drivers/cpufreq/db8500-cpufreq.c
> +++ b/drivers/cpufreq/db8500-cpufreq.c
> @@ -14,10 +14,11 @@
>  #include <linux/delay.h>
>  #include <linux/slab.h>
>  #include <linux/platform_device.h>
> -#include <linux/mfd/dbx500-prcmu.h>
> +#include <linux/clk.h>
>  #include <mach/id.h>
>
>  static struct cpufreq_frequency_table *freq_table;
> +static struct clk *armss_clk;
>
>  static struct freq_attr *db8500_cpufreq_attr[] = {
>         &cpufreq_freq_attr_scaling_available_freqs,
> @@ -58,9 +59,9 @@ static int db8500_cpufreq_target(struct cpufreq_policy *policy,
>         for_each_cpu(freqs.cpu, policy->cpus)
>                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
>
> -       /* request the PRCM unit for opp change */
> -       if (prcmu_set_arm_opp(freq_table[idx].index)) {
> -               pr_err("db8500-cpufreq:  Failed to set OPP level\n");
> +       /* update armss clk frequency */
> +       if (clk_set_rate(armss_clk, freq_table[idx].frequency * 1000)) {
> +               pr_err("db8500-cpufreq: Failed to update armss clk\n");
>                 return -EINVAL;
>         }
>
> @@ -74,16 +75,16 @@ static int db8500_cpufreq_target(struct cpufreq_policy *policy,
>  static unsigned int db8500_cpufreq_getspeed(unsigned int cpu)
>  {
>         int i = 0;
> -       /* request the prcm to get the current ARM opp */
> -       int opp = prcmu_get_arm_opp();
> +       unsigned long freq = clk_get_rate(armss_clk) / 1000;
>
>         while (freq_table[i].frequency != CPUFREQ_TABLE_END) {
> -               if (opp == freq_table[i].index)
> +               if (freq <= freq_table[i].frequency)
>                         return freq_table[i].frequency;
>                 i++;
>         }
>
> -       /* We could not find a corresponding opp frequency. */
> +       /* We could not find a corresponding frequency. */
> +       pr_err("db8500-cpufreq: Failed to find cpufreq speed\n");
>         return 0;
>  }
>
> @@ -92,6 +93,12 @@ static int __cpuinit db8500_cpufreq_init(struct cpufreq_policy *policy)
>         int i = 0;
>         int res;
>
> +       armss_clk = clk_get(NULL, "armss");
> +       if (IS_ERR(armss_clk)) {
> +               pr_err("db8500-cpufreq : Failed to get armss clk\n");
> +               return PTR_ERR(armss_clk);
> +       }
> +
>         pr_info("db8500-cpufreq : Available frequencies:\n");
>         while (freq_table[i].frequency != CPUFREQ_TABLE_END) {
>                 pr_info("  %d Mhz\n", freq_table[i].frequency/1000);
> @@ -104,6 +111,7 @@ static int __cpuinit db8500_cpufreq_init(struct cpufreq_policy *policy)
>                 cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
>         else {
>                 pr_err("db8500-cpufreq : Failed to read policy table\n");
> +               clk_put(armss_clk);
>                 return res;
>         }
>
> --
> 1.7.10
>

Just a kind reminder on this Rafael; trying to collect acks, do you
think we can advise Mike to merge this though his clk tree?

Kind regards
Ulf Hansson

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