On Sat, Dec 17, 2011 at 10:29:29AM +0100, Arnd Bergmann wrote:
On Saturday 17 December 2011 16:00:03 Richard Zhao wrote:
On Fri, Dec 16, 2011 at 08:32:35AM -0600, Rob Herring wrote:
On 12/16/2011 04:30 AM, Richard Zhao wrote:
It support single core and multi-core ARM SoCs. But it assume all cores share the same frequency and voltage.
Signed-off-by: Richard Zhao richard.zhao@linaro.org
drivers/cpufreq/Kconfig.arm | 8 ++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/arm-cpufreq.c | 269 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 278 insertions(+), 0 deletions(-) create mode 100644 drivers/cpufreq/arm-cpufreq.c
What makes this specific to ARM and not a generic DT + clk api + regulator api driver?
smp loops_per_jiffy update needs arm header <asm/cpu.h>.
I would suggest to instead change the definition of adjust_jiffies in the core so it can be overridden by the architecture, like this
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 987a165..174584d 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -189,6 +189,7 @@ EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
- systems as each CPU might be scaled differently. So, use the arch
- per-CPU loops_per_jiffy value wherever possible.
*/ +#ifndef adjust_jiffies #ifndef CONFIG_SMP static unsigned long l_p_j_ref; static unsigned int l_p_j_ref_freq; @@ -218,7 +219,8 @@ static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) { return; } -#endif +#endif /* CONFIG_SMP */ +#endif /* adjust_jiffies */ /**
Then ARM (and any others that want the driver) can provide their own implementation and set
#define adjust_jiffies(val, ci) adjust_jiffies((val), (ci))
to let the core use that instead of the generic UP version.
While we're there, we should probably try to fix drivers that use loops_per_jiffy, because that is not what they think it is on SMP.
Or let different arch register its different CPUFREQ_TRANSITION_NOTIFIER ?
Thanks Richard
Arnd
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