[PATCH 4/5] ARM: S3C6410: Support 800MHz operation in cpufreq

Sangbeom Kim sbkim73 at samsung.com
Wed Jun 1 06:30:42 EDT 2011


Hi, Mark

800Mhz S3C6410 is only supplied by customer request.
800Mhz dvfs operation should be controlled carefully.
(Stable VDD_ARM should be supplied)
To optimize s3c6410 dvfs operation, not only ARMCLK
But also HCLK should do dvfs.
In other words, VDD_INT, as well as VDD_ARM should be controlled.

Thanks and regards,
SB Kim

On Wed, Jun 1, 2011 at 6:45 PM, Mark Brown
> At least some newer S3C6410 silicon supports operation up to 800MHz rather
> than just 667MHz. Unfortunately I don't have access to any of
> documentation
> of this other than some running systems, add a new cpufreq table entry for
> this based on the behaviour of those systems.
> 
> Signed-off-by: Mark Brown <broonie at opensource.wolfsonmicro.com>
> ---
>  drivers/cpufreq/s3c64xx.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/cpufreq/s3c64xx.c b/drivers/cpufreq/s3c64xx.c
> index fc3f180..fc69178 100644
> --- a/drivers/cpufreq/s3c64xx.c
> +++ b/drivers/cpufreq/s3c64xx.c
> @@ -31,6 +31,7 @@ static struct s3c64xx_dvfs s3c64xx_dvfs_table[] = {
>  	[1] = { 1050000, 1150000 },
>  	[2] = { 1100000, 1150000 },
>  	[3] = { 1200000, 1350000 },
> +	[4] = { 1300000, 1350000 },
>  };
> 
>  static struct cpufreq_frequency_table s3c64xx_freq_table[] = {
> @@ -43,6 +44,7 @@ static struct cpufreq_frequency_table
> s3c64xx_freq_table[] = {
>  	{ 2, 532000 },
>  	{ 2, 533000 },
>  	{ 3, 667000 },
> +	{ 4, 800000 },
>  	{ 0, CPUFREQ_TABLE_END },
>  };
>  #endif
> --
> 1.7.5.3
> 
> 
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