PM / Domains: Make it possible to assign names to generic PM domains

Add a name member pointer to struct generic_pm_domain and use it in
diagnostic messages regarding the domain power-off and power-on
latencies.  Update the ARM shmobile SH7372 code to assign names to
the PM domains used by it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

3 files changed, 25 insertions, 6 deletions

diff --git a/arch/arm/mach-shmobile/pm-sh7372.c b/arch/arm/mach-shmobile/pm-sh7372.c
index adf1765e69c6..8d9ea8924ed3 100644
--- a/arch/arm/mach-shmobile/pm-sh7372.c
+++ b/arch/arm/mach-shmobile/pm-sh7372.c
@@ -101,8 +101,8 @@ static int pd_power_down(struct generic_pm_domain *genpd)
         }
 
         if (!sh7372_pd->no_debug)
-                pr_debug("sh7372 power domain down 0x%08x -> PSTR = 0x%08x\n",
-                         mask, __raw_readl(PSTR));
+                pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n",
+                         genpd->name, mask, __raw_readl(PSTR));
 
         return 0;
 }
@@ -133,8 +133,8 @@ static int __pd_power_up(struct sh7372_pm_domain *sh7372_pd, bool do_resume)
                 ret = -EIO;
 
         if (!sh7372_pd->no_debug)
-                pr_debug("sh7372 power domain up 0x%08x -> PSTR = 0x%08x\n",
-                         mask, __raw_readl(PSTR));
+                pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
+                         sh7372_pd->genpd.name, mask, __raw_readl(PSTR));
 
  out:
         if (ret == 0 && sh7372_pd->resume && do_resume)
@@ -233,18 +233,22 @@ void sh7372_pm_add_subdomain(struct sh7372_pm_domain *sh7372_pd,
 }
 
 struct sh7372_pm_domain sh7372_a4lc = {
+        .genpd.name = "A4LC",
         .bit_shift = 1,
 };
 
 struct sh7372_pm_domain sh7372_a4mp = {
+        .genpd.name = "A4MP",
         .bit_shift = 2,
 };
 
 struct sh7372_pm_domain sh7372_d4 = {
+        .genpd.name = "D4",
         .bit_shift = 3,
 };
 
 struct sh7372_pm_domain sh7372_a4r = {
+        .genpd.name = "A4R",
         .bit_shift = 5,
         .gov = &sh7372_always_on_gov,
         .suspend = sh7372_a4r_suspend,
@@ -253,14 +257,17 @@ struct sh7372_pm_domain sh7372_a4r = {
 };
 
 struct sh7372_pm_domain sh7372_a3rv = {
+        .genpd.name = "A3RV",
         .bit_shift = 6,
 };
 
 struct sh7372_pm_domain sh7372_a3ri = {
+        .genpd.name = "A3RI",
         .bit_shift = 8,
 };
 
 struct sh7372_pm_domain sh7372_a3sp = {
+        .genpd.name = "A3SP",
         .bit_shift = 11,
         .gov = &sh7372_always_on_gov,
         .no_debug = true,
@@ -275,6 +282,7 @@ static void sh7372_a3sp_init(void)
 }
 
 struct sh7372_pm_domain sh7372_a3sg = {
+        .genpd.name = "A3SG",
         .bit_shift = 13,
 };
 
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 5a8d67d51f0e..ad6ba2e04677 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -209,8 +209,13 @@ int __pm_genpd_poweron(struct generic_pm_domain *genpd)
                         goto err;
 
                 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-                if (elapsed_ns > genpd->power_on_latency_ns)
+                if (elapsed_ns > genpd->power_on_latency_ns) {
                         genpd->power_on_latency_ns = elapsed_ns;
+                        if (genpd->name)
+                                pr_warning("%s: Power-on latency exceeded, "
+                                        "new value %lld ns\n", genpd->name,
+                                        elapsed_ns);
+                }
         }
 
         genpd_set_active(genpd);
@@ -428,8 +433,13 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
                 }
 
                 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-                if (elapsed_ns > genpd->power_off_latency_ns)
+                if (elapsed_ns > genpd->power_off_latency_ns) {
                         genpd->power_off_latency_ns = elapsed_ns;
+                        if (genpd->name)
+                                pr_warning("%s: Power-off latency exceeded, "
+                                        "new value %lld ns\n", genpd->name,
+                                        elapsed_ns);
+                }
         }
 
         genpd->status = GPD_STATE_POWER_OFF;
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index fbb81bc5065a..fb809b904891 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -50,6 +50,7 @@ struct generic_pm_domain {
         struct mutex lock;
         struct dev_power_governor *gov;
         struct work_struct power_off_work;
+        char *name;
         unsigned int in_progress;       /* Number of devices being suspended now */
         atomic_t sd_count;      /* Number of subdomains with power "on" */
         enum gpd_status status; /* Current state of the domain */