[PATCHv2] omap2+: pm: cpufreq: Fix loops_per_jiffy calculation

Santosh Shilimkar santosh.shilimkar at ti.com
Fri Jun 24 10:35:23 EDT 2011


On 6/24/2011 7:23 PM, Sanjeev Premi wrote:
> Currently, loops_per_jiffy is being calculated twice for
> non-SMP processors.
>   - Before calling cpufreq_notify_transition()
>   - From within cpufreq_notify_transition()
>
> Double adjustment leads to incorrect value being assigned to
> loops_per_jiffy. This manifests as incorrect BogoMIPS in
> "cat /proc/cpuinfo".
>
> The value of loops_per_jiffy needs to be calculated only
> when CONFIG_SMP is true. It is the core change included
> in this patch.
>
> The patch also leverages the definition of for_each_cpu()
> with and without CONFIG_SMP to consolidate the mechanism
> to call cpufreq_notify_transition().
>
> Signed-off-by: Sanjeev Premi<premi at ti.com>

NAK. This patch again doesn't make sense considering your issue.
Also jiffies should not be undated before changing the freq.
If the set_rate failed for some reason then you will have wrong
jiffies value.

I understand your issue now. The code for global lpj updation
should have been checking smp_on_up() instead of is_smp().
That one line change is enough. I will post a patch on
the same once I reach to office.

Regards
Santosh



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