Subject: [PATCH 5/7] ARM: OMAP2+: PM debug: trace the functional power domains states

From: [email-masked] (Kevin Hilman)
Date: Wed, 12 Sep 2012 16:47:37 -0700

Jean Pihet <[email-masked]> writes:

> Trace the power domain transitions using the functional power states,
> which include the power and logic states.

Just to be clear, this means that a trace will only contain functional
power state changes, not logical ones, correct?

> While at it, fix the trace in the case a power domain did not hit
> the desired state, as reported by Paul Walmsley.

What was broken here?  needs a bit more description.  To me it sounds
like a fix that should be a separate patch.

> Reported-by: Paul Walmsley <[email-masked]>
> Signed-off-by: Jean Pihet <[email-masked]>
> ---
>  arch/arm/mach-omap2/powerdomain.c |   23 +++++++++++++----------
>  1 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c
> index 267241f..2277ad3 100644
> --- a/arch/arm/mach-omap2/powerdomain.c
> +++ b/arch/arm/mach-omap2/powerdomain.c
> @@ -144,7 +144,7 @@ static void _update_logic_membank_counters(struct powerdomain *pwrdm)
>  static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag)
>  {
>  
> -	int prev, state, trace_state = 0;
> +	int prev, next, state, trace_state;
>  
>  	if (pwrdm == NULL)
>  		return -EINVAL;
> @@ -165,10 +165,10 @@ static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag)
>  		 * If the power domain did not hit the desired state,
>  		 * generate a trace event with both the desired and hit states
>  		 */
> -		if (state != prev) {
> +		next = pwrdm_read_next_fpwrst(pwrdm);
> +		if (next != prev) {
>  			trace_state = (PWRDM_TRACE_STATES_FLAG |
> -				       ((state & OMAP_POWERSTATE_MASK) << 8) |
> -				       ((prev & OMAP_POWERSTATE_MASK) << 0));
> +				       (next << 8) | (prev << 0));
>  			trace_power_domain_target(pwrdm->name, trace_state,
>  						  smp_processor_id());
>  		}
> @@ -723,6 +723,10 @@ int pwrdm_set_fpwrst(struct powerdomain *pwrdm, enum pwrdm_func_state fpwrst)
>  		}
>  	}
>  
> +	/* Trace the pwrdm desired target state */
> +	trace_power_domain_target(pwrdm->name, next_fpwrst,
> +				  smp_processor_id());

Use of smp_processor_id() here will require the same care as pointed out
by Roger Quadros in [PATCH] perf: Use raw_smp_processor_id insted of
smp_processor_id.

Kevin

>  	if (logic != pwrdm_read_logic_retst(pwrdm))
>  		pwrdm_set_logic_retst(pwrdm, logic);
>  
> @@ -776,6 +780,10 @@ int pwrdm_set_next_fpwrst(struct powerdomain *pwrdm,
>  
>  	spin_lock_irqsave(&pwrdm->lock, flags);
>  
> +	/* Trace the pwrdm desired target state */
> +	trace_power_domain_target(pwrdm->name, fpwrst,
> +				  smp_processor_id());
> +
>  	ret = pwrdm_set_logic_retst(pwrdm, logic);
>  	if (ret)
>  		pr_err("%s: unable to set logic state %0x of powerdomain: %s\n",
> @@ -821,13 +829,8 @@ int pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
>  	pr_debug("powerdomain: setting next powerstate for %s to %0x\n",
>  		 pwrdm->name, pwrst);
>  
> -	if (arch_pwrdm && arch_pwrdm->pwrdm_set_next_pwrst) {
> -		/* Trace the pwrdm desired target state */
> -		trace_power_domain_target(pwrdm->name, pwrst,
> -					  smp_processor_id());
> -		/* Program the pwrdm desired target state */
> +	if (arch_pwrdm && arch_pwrdm->pwrdm_set_next_pwrst)
>  		ret = arch_pwrdm->pwrdm_set_next_pwrst(pwrdm, pwrst);
> -	}
>  
>  	return ret;
>  }