Nori, Sekhar <nsek...@ti.com> writes:

> Update the clock framework for dynamic CPU frequency change.
>
> clk_round_rate, clk_set_rate have been updated to handle dynamic frequency
> changes.
>
> davinci_set_pllrate() changes the PLL rate of a given PLL. This function
> has been presented as a generic function though it has been tested only
> on OMAP-L138 EVM. No other currently available DaVinci device will probably
> use this function, but any future device specific changes will hopefully be
> small enough to get taken care using a cpu_is_xxx() macro.
>
> The clk_set_parent() API is implemented to reparent clocks to
> asynchronous domains where possible and insulate them from frequency
> changes.
>
> An inline function is introduced to get to the parent PLL of a given
> clock. This is useful in finding out all the clocks which gets
> affected by a PLL rate change.
>
> Finally, another function is implemented to recalculate the PLL derived
> rates after the PLL rate has been changed.
>
> Tested on OMAP-L138 EVM.
>
> Signed-off-by: Sekhar Nori <nsek...@ti.com>

Looks pretty good, minor comment below.  And would also be nice to at
least boot test on one of the DM* boards.

> ---
> arch/arm/mach-davinci/clock.c |  140 ++++++++++++++++++++++++++++++++++++++++-
>  arch/arm/mach-davinci/clock.h |   18 +++++
>  2 files changed, 155 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c
> index 83d54d5..5cbb95e 100644
> --- a/arch/arm/mach-davinci/clock.c
> +++ b/arch/arm/mach-davinci/clock.c
> @@ -19,6 +19,7 @@
>  #include <linux/mutex.h>
>  #include <linux/platform_device.h>
>  #include <linux/io.h>
> +#include <linux/delay.h>
>  
>  #include <mach/hardware.h>
>  
> @@ -99,20 +100,50 @@ long clk_round_rate(struct clk *clk, unsigned long rate)
>       if (clk == NULL || IS_ERR(clk))
>               return -EINVAL;
>  
> +     if (clk->round_rate)
> +             return clk->round_rate(clk, rate);
> +
>       return clk->rate;
>  }
>  EXPORT_SYMBOL(clk_round_rate);
>  
>  int clk_set_rate(struct clk *clk, unsigned long rate)
>  {
> +     unsigned long flags;
> +     int ret = -EINVAL;
> +
>       if (clk == NULL || IS_ERR(clk))
> -             return -EINVAL;
> +             return ret;

should probably also check for a non-NULL clk->set_rate here since
it's only defined for da850 currently.

Kevin 


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