[RFC][PATCH 1/5] PM / shmobile: Set SH7372 PM domain on/off latencies directly

From: Rafael J. Wysocki
Date: Sat Jul 21 2012 - 17:52:32 EST



The results of adaptive latency computations in __pm_genpd_poweron()
and pm_genpd_poweroff() show that the power on/power off latencies
of all power domains in SH7372 are a little below 250 us. Therefore,
if 250 us is used as the common initial value of the latency fields
in struct generic_pm_domain for all domains, the latency values
will never have to change at run time and there won't be any overhead
related to re-computation of the corresponding PM QoS data.

Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
---
arch/arm/mach-shmobile/pm-sh7372.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

Index: linux/arch/arm/mach-shmobile/pm-sh7372.c
===================================================================
--- linux.orig/arch/arm/mach-shmobile/pm-sh7372.c
+++ linux/arch/arm/mach-shmobile/pm-sh7372.c
@@ -71,6 +71,8 @@

#ifdef CONFIG_PM

+#define PM_DOMAIN_ON_OFF_LATENCY_NS 250000
+
static int sh7372_a4r_pd_suspend(void)
{
sh7372_intcs_suspend();
@@ -99,32 +101,46 @@ static int sh7372_a3sp_pd_suspend(void)
static struct rmobile_pm_domain sh7372_pm_domains[] = {
{
.genpd.name = "A4LC",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 1,
},
{
.genpd.name = "A4MP",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 2,
},
{
.genpd.name = "D4",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 3,
},
{
.genpd.name = "A4R",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 5,
.suspend = sh7372_a4r_pd_suspend,
.resume = sh7372_intcs_resume,
},
{
.genpd.name = "A3RV",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 6,
},
{
.genpd.name = "A3RI",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 8,
},
{
.genpd.name = "A4S",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 10,
.gov = &pm_domain_always_on_gov,
.no_debug = true,
@@ -132,6 +148,8 @@ static struct rmobile_pm_domain sh7372_p
},
{
.genpd.name = "A3SP",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 11,
.gov = &pm_domain_always_on_gov,
.no_debug = true,
@@ -139,6 +157,8 @@ static struct rmobile_pm_domain sh7372_p
},
{
.genpd.name = "A3SG",
+ .genpd.power_on_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
+ .genpd.power_off_latency_ns = PM_DOMAIN_ON_OFF_LATENCY_NS,
.bit_shift = 13,
},
};

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