[PATCH v2 1/9] ARM: S3C24XX: cpufreq-utils: don't write raw values to MPLLCON when using ccf

Heiko Stübner heiko at sntech.de
Wed Apr 23 14:11:35 PDT 2014


Am Mittwoch, 23. April 2014, 22:55:51 schrieb Tomasz Figa:
> Hi,
> 
> On 23.04.2014 22:42, Sergei Shtylyov wrote:
> > Hello.
> > 
> > On 04/23/2014 11:34 PM, Heiko Stübner wrote:
> >> The s3c24xx cpufreq driver needs to change the mpll speed and was doing
> >> this by writing raw values from a translation table into the MPLLCON
> >> register.
> >> 
> >> Change this to use a regular clk_set_rate call when using the common
> >> clock framework and only write the raw value in the samsung_clock case.
> >> 
> >> To not needing to create additional infrastructure for this, the mpll
> >> clock
> >> is requested at the first call to s3c2410_set_fvco().
> >> 
> >> Signed-off-by: Heiko Stuebner <heiko at sntech.de>
> >> ---
> >> 
> >>   arch/arm/mach-s3c24xx/cpufreq-utils.c | 14 ++++++++++++++
> >>   1 file changed, 14 insertions(+)
> >> 
> >> diff --git a/arch/arm/mach-s3c24xx/cpufreq-utils.c
> >> b/arch/arm/mach-s3c24xx/cpufreq-utils.c
> >> index 2a0aa56..d5e797b 100644
> >> --- a/arch/arm/mach-s3c24xx/cpufreq-utils.c
> >> +++ b/arch/arm/mach-s3c24xx/cpufreq-utils.c
> > 
> > [...]
> > 
> >> @@ -60,5 +61,18 @@ void s3c2410_cpufreq_setrefresh(struct
> >> s3c_cpufreq_config *cfg)
> >> 
> >>    */
> >>   
> >>   void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg)
> >>   {
> >> 
> >> +#ifdef CONFIG_SAMSUNG_CLOCK
> >> 
> >>       __raw_writel(cfg->pll.driver_data, S3C2410_MPLLCON);
> >> 
> >> +#endif
> >> +
> >> +#ifdef CONFIG_COMMON_CLK
> >> +    static struct clk *mpll;
> >> +
> >> +    if (!mpll)
> >> 
> >     You are testing uninitialized variable. This check wouldn't make
> > 
> > much sense even if the variable was initialized.
> 
> I should probably add that NULL is considered a valid clock handle by
> Common Clock Framework.
> 
> If there is really no way to pass the clock to this function then
> probably a global variable initialized by some code running earlier than
> this function could be called would be a better choice.

*grrr* :-) ... ok I'll try to find another way (again) to do this


> Anyway, Heiko, thanks for working on this. I'll try to review rest of
> the series soon. (I'm attending the ELC next week, though, so I'm not
> sure if I find some time then, though.)

Just as a reminder, there isn't this much to still review, as you 
Acked/Reviewed most of the series in v1 and only this patch as well as 2 and 5 
still need a review/ack - and the only changes are fixes for your comments ;-)


Heiko



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