Subject: [PATCHv4 7/8] ARM: OMAP: clockdomain: add support for preventing autodep delete

From: [email-masked] (Rajendra Nayak)
Date: Mon, 16 Jul 2012 16:30:35 +0530

Hi Tero,

On Friday 13 July 2012 07:49 PM, Tero Kristo wrote:
> Some clockdomains bug out if their autodeps are deleted before idle.
> This happens namely with OMAP3 PER domain, it will bug out if it
> doesn't have wakedeps enabled when it enters off-mode. This patch
> adds support for new flag 'CLKDM_NO_AUTODEP_DISABLE' which does this.

I had one more thought on how we could handle this (without adding a new
flag :-))
How about marking OMAP3 PER with a CLKDM_NO_AUTODEPS (already existing
flag) and setting a sleep/wakeup dependency of OMAP3 PER with MPU and
IVA one time sometime during late PM init. Because thats what we intent
to do, which is have a sleep/wakeup dependency set *always* and never
try to remove it, right?

regards,
Rajendra

>
> Signed-off-by: Tero Kristo<[email-masked]>
> ---
>   arch/arm/mach-omap2/clockdomain.c |    3 +++
>   arch/arm/mach-omap2/clockdomain.h |    4 ++++
>   2 files changed, 7 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c
> index 7f5423e..56cef58 100644
> --- a/arch/arm/mach-omap2/clockdomain.c
> +++ b/arch/arm/mach-omap2/clockdomain.c
> @@ -201,6 +201,9 @@ void _clkdm_del_autodeps(struct clockdomain *clkdm)
>   	if (!autodeps || clkdm->flags&  CLKDM_NO_AUTODEPS)
>   		return;
>
> +	if (clkdm->flags&  CLKDM_NO_AUTODEP_DISABLE)
> +		return;
> +
>   	for (autodep = autodeps; autodep->clkdm.ptr; autodep++) {
>   		if (IS_ERR(autodep->clkdm.ptr))
>   			continue;
> diff --git a/arch/arm/mach-omap2/clockdomain.h b/arch/arm/mach-omap2/clockdomain.h
> index 373399a..1fc5314 100644
> --- a/arch/arm/mach-omap2/clockdomain.h
> +++ b/arch/arm/mach-omap2/clockdomain.h
> @@ -31,12 +31,16 @@
>    *
>    * CLKDM_NO_AUTODEPS: Prevent "autodeps" from being added/removed from this
>    *     clockdomain.  (Currently, this applies to OMAP3 clockdomains only.)
> + * CLKDM_NO_AUTODEP_DISABLE: Prevent clockdomain code from deleting autodeps.
> + *     Needed for PER domain on omap3, as it will bug out with off-mode if
> + *     wakedeps are removed.
>    */
>   #define CLKDM_CAN_FORCE_SLEEP			(1<<  0)
>   #define CLKDM_CAN_FORCE_WAKEUP			(1<<  1)
>   #define CLKDM_CAN_ENABLE_AUTO			(1<<  2)
>   #define CLKDM_CAN_DISABLE_AUTO			(1<<  3)
>   #define CLKDM_NO_AUTODEPS			(1<<  4)
> +#define CLKDM_NO_AUTODEP_DISABLE		(1<<  5)
>
>   #define CLKDM_CAN_HWSUP		(CLKDM_CAN_ENABLE_AUTO | CLKDM_CAN_DISABLE_AUTO)
>   #define CLKDM_CAN_SWSUP		(CLKDM_CAN_FORCE_SLEEP | CLKDM_CAN_FORCE_WAKEUP)