PM / shmobile: Remove the stay_on flag from SH7372's PM domains
SH7372 uses two independent mechanisms for ensuring that power
domains will never be turned off: the stay_on flag and the "always
on" domain governor. Moreover, the "always on" governor is only taken
into accout by runtime PM code paths, while the stay_on flag affects
all attempts to turn the given domain off. Thus setting the stay_on
flag causes the "always on" governor to be unnecessary, which is
quite confusing.
However, the stay_on flag is currently only set for two domains: A3SP
and A4S. Moreover, it only is set for the A3SP domain if
console_suspend_enabled is set, so stay_on won't be necessary for
that domain any more if console_suspend_enabled is checked directly
in its .suspend() routine. [This requires domain .suspend() to
return a result, but that is a minor modification.] Analogously,
stay_on won't be necessary for the A4S domain if it's .suspend()
routine always returns an error code.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
diff --git a/arch/arm/mach-shmobile/include/mach/sh7372.h b/arch/arm/mach-shmobile/include/mach/sh7372.h
index d0731d9..8254ab8 100644
--- a/arch/arm/mach-shmobile/include/mach/sh7372.h
+++ b/arch/arm/mach-shmobile/include/mach/sh7372.h
@@ -480,11 +480,10 @@
struct sh7372_pm_domain {
struct generic_pm_domain genpd;
struct dev_power_governor *gov;
- void (*suspend)(void);
+ int (*suspend)(void);
void (*resume)(void);
unsigned int bit_shift;
bool no_debug;
- bool stay_on;
};
static inline struct sh7372_pm_domain *to_sh7372_pd(struct generic_pm_domain *d)
diff --git a/arch/arm/mach-shmobile/pm-sh7372.c b/arch/arm/mach-shmobile/pm-sh7372.c
index 1e659d7..7fda230 100644
--- a/arch/arm/mach-shmobile/pm-sh7372.c
+++ b/arch/arm/mach-shmobile/pm-sh7372.c
@@ -82,11 +82,12 @@
struct sh7372_pm_domain *sh7372_pd = to_sh7372_pd(genpd);
unsigned int mask = 1 << sh7372_pd->bit_shift;
- if (sh7372_pd->suspend)
- sh7372_pd->suspend();
+ if (sh7372_pd->suspend) {
+ int ret = sh7372_pd->suspend();
- if (sh7372_pd->stay_on)
- return 0;
+ if (ret)
+ return ret;
+ }
if (__raw_readl(PSTR) & mask) {
unsigned int retry_count;
@@ -113,9 +114,6 @@
unsigned int retry_count;
int ret = 0;
- if (sh7372_pd->stay_on)
- goto out;
-
if (__raw_readl(PSTR) & mask)
goto out;
@@ -148,10 +146,11 @@
return __pd_power_up(to_sh7372_pd(genpd), true);
}
-static void sh7372_a4r_suspend(void)
+static int sh7372_a4r_suspend(void)
{
sh7372_intcs_suspend();
__raw_writel(0x300fffff, WUPRMSK); /* avoid wakeup */
+ return 0;
}
static bool pd_active_wakeup(struct device *dev)
@@ -243,7 +242,6 @@
.gov = &pm_domain_always_on_gov,
.suspend = sh7372_a4r_suspend,
.resume = sh7372_intcs_resume,
- .stay_on = true,
};
struct sh7372_pm_domain sh7372_a3rv = {
@@ -256,29 +254,40 @@
.bit_shift = 8,
};
+static int sh7372_a4s_suspend(void)
+{
+ /*
+ * The A4S domain contains the CPU core and therefore it should
+ * only be turned off if the CPU is in use.
+ */
+ return -EBUSY;
+}
+
struct sh7372_pm_domain sh7372_a4s = {
.genpd.name = "A4S",
.bit_shift = 10,
.gov = &pm_domain_always_on_gov,
.no_debug = true,
- .stay_on = true,
+ .suspend = sh7372_a4s_suspend,
};
+static int sh7372_a3sp_suspend(void)
+{
+ /*
+ * Serial consoles make use of SCIF hardware located in A3SP,
+ * keep such power domain on if "no_console_suspend" is set.
+ */
+ return console_suspend_enabled ? -EBUSY : 0;
+}
+
struct sh7372_pm_domain sh7372_a3sp = {
.genpd.name = "A3SP",
.bit_shift = 11,
.gov = &pm_domain_always_on_gov,
.no_debug = true,
+ .suspend = sh7372_a3sp_suspend,
};
-static void sh7372_a3sp_init(void)
-{
- /* serial consoles make use of SCIF hardware located in A3SP,
- * keep such power domain on if "no_console_suspend" is set.
- */
- sh7372_a3sp.stay_on = !console_suspend_enabled;
-}
-
struct sh7372_pm_domain sh7372_a3sg = {
.genpd.name = "A3SG",
.bit_shift = 13,
@@ -508,7 +517,7 @@
/* convert INTC mask and sense to SYSC mask and sense */
sh7372_setup_sysc(msk, msk2);
- if (!sh7372_a3sp.stay_on &&
+ if (!console_suspend_enabled &&
sh7372_a4s.genpd.status == GPD_STATE_POWER_OFF) {
/* enter A4S sleep with PLLC0 off */
pr_debug("entering A4S\n");
@@ -544,8 +553,6 @@
/* do not convert A3SM, A3SP, A3SG, A4R power down into A4S */
__raw_writel(0, PDNSEL);
- sh7372_a3sp_init();
-
sh7372_suspend_init();
sh7372_cpuidle_init();
}