Re: [PATCHv5 6/8] ARM: OMAP4: pwrdm: add support for reading prev logic and mem states

[Kevin Hilman <khilman@ti.com>]

Tero Kristo <t-kristo@ti.com> writes:

> On OMAP4, there is no support to read previous logic state
> or previous memory state achieved when a power domain transitions
> to RET. Instead there are module level context registers.
>
> In order to support the powerdomain level logic/mem_off_counters
> on OMAP4, instead use the previous power state achieved (RET) and
> the *programmed* logic/mem RET state to derive if a powerdomain lost
> logic or did not.
>
> If the powerdomain is programmed to enter RET state and lose logic
> in RET state, knowing that the powerdomain entered RET is good enough
> to derive that the logic was lost as well, in such cases.
>
> Signed-off-by: Tero Kristo <t-kristo@ti.com>

Looks OK, but these new functions need some kerneldoc to describe the
decision making.

Kevin

> ---
>  arch/arm/mach-omap2/powerdomain44xx.c |   32 ++++++++++++++++++++++++++++++++
>  1 files changed, 32 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/powerdomain44xx.c b/arch/arm/mach-omap2/powerdomain44xx.c
> index 601325b..ab00736 100644
> --- a/arch/arm/mach-omap2/powerdomain44xx.c
> +++ b/arch/arm/mach-omap2/powerdomain44xx.c
> @@ -151,6 +151,21 @@ static int omap4_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
>  	return v;
>  }
>  
> +static int omap4_pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
> +{
> +	int state;
> +
> +	state = omap4_pwrdm_read_prev_pwrst(pwrdm);
> +
> +	if (state == PWRDM_POWER_OFF)
> +		return PWRDM_POWER_OFF;
> +
> +	if (state != PWRDM_POWER_RET)
> +		return PWRDM_POWER_ON;
> +
> +	return omap4_pwrdm_read_logic_retst(pwrdm);
> +}
> +
>  static int omap4_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
>  {
>  	u32 m, v;
> @@ -179,6 +194,21 @@ static int omap4_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
>  	return v;
>  }
>  
> +static int omap4_pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
> +{
> +	int state;
> +
> +	state = omap4_pwrdm_read_prev_pwrst(pwrdm);
> +
> +	if (state == PWRDM_POWER_OFF)
> +		return PWRDM_POWER_OFF;
> +
> +	if (state != PWRDM_POWER_RET)
> +		return PWRDM_POWER_ON;
> +
> +	return omap4_pwrdm_read_mem_retst(pwrdm, bank);
> +}
> +
>  static int omap4_pwrdm_wait_transition(struct powerdomain *pwrdm)
>  {
>  	u32 c = 0;
> @@ -217,9 +247,11 @@ struct pwrdm_ops omap4_pwrdm_operations = {
>  	.pwrdm_clear_all_prev_pwrst	= omap4_pwrdm_clear_all_prev_pwrst,
>  	.pwrdm_set_logic_retst	= omap4_pwrdm_set_logic_retst,
>  	.pwrdm_read_logic_pwrst	= omap4_pwrdm_read_logic_pwrst,
> +	.pwrdm_read_prev_logic_pwrst	= omap4_pwrdm_read_prev_logic_pwrst,
>  	.pwrdm_read_logic_retst	= omap4_pwrdm_read_logic_retst,
>  	.pwrdm_read_mem_pwrst	= omap4_pwrdm_read_mem_pwrst,
>  	.pwrdm_read_mem_retst	= omap4_pwrdm_read_mem_retst,
> +	.pwrdm_read_prev_mem_pwrst	= omap4_pwrdm_read_prev_mem_pwrst,
>  	.pwrdm_set_mem_onst	= omap4_pwrdm_set_mem_onst,
>  	.pwrdm_set_mem_retst	= omap4_pwrdm_set_mem_retst,
>  	.pwrdm_wait_transition	= omap4_pwrdm_wait_transition,