Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 74 insertions, 40 deletions

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 6ac9a7f33b64..56705b52758e 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -104,6 +104,7 @@ static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
 
 static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 {
+	unsigned int state_idx = genpd->state_idx;
 	ktime_t time_start;
 	s64 elapsed_ns;
 	int ret;
@@ -120,10 +121,10 @@ static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 		return ret;
 
 	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-	if (elapsed_ns <= genpd->power_on_latency_ns)
+	if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
 		return ret;
 
-	genpd->power_on_latency_ns = elapsed_ns;
+	genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
 	genpd->max_off_time_changed = true;
 	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 		 genpd->name, "on", elapsed_ns);
@@ -133,6 +134,7 @@ static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 
 static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 {
+	unsigned int state_idx = genpd->state_idx;
 	ktime_t time_start;
 	s64 elapsed_ns;
 	int ret;
@@ -149,10 +151,10 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 		return ret;
 
 	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-	if (elapsed_ns <= genpd->power_off_latency_ns)
+	if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
 		return ret;
 
-	genpd->power_off_latency_ns = elapsed_ns;
+	genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
 	genpd->max_off_time_changed = true;
 	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 		 genpd->name, "off", elapsed_ns);
@@ -162,7 +164,7 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 
 /**
  * genpd_queue_power_off_work - Queue up the execution of genpd_poweroff().
- * @genpd: PM domait to power off.
+ * @genpd: PM domain to power off.
  *
  * Queue up the execution of genpd_poweroff() unless it's already been done
  * before.
@@ -172,16 +174,15 @@ static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 	queue_work(pm_wq, &genpd->power_off_work);
 }
 
-static int genpd_poweron(struct generic_pm_domain *genpd);
-
 /**
- * __genpd_poweron - Restore power to a given PM domain and its masters.
+ * genpd_poweron - Restore power to a given PM domain and its masters.
  * @genpd: PM domain to power up.
+ * @depth: nesting count for lockdep.
  *
  * Restore power to @genpd and all of its masters so that it is possible to
  * resume a device belonging to it.
  */
-static int __genpd_poweron(struct generic_pm_domain *genpd)
+static int genpd_poweron(struct generic_pm_domain *genpd, unsigned int depth)
 {
 	struct gpd_link *link;
 	int ret = 0;
@@ -196,11 +197,16 @@ static int __genpd_poweron(struct generic_pm_domain *genpd)
 	 * with it.
 	 */
 	list_for_each_entry(link, &genpd->slave_links, slave_node) {
-		genpd_sd_counter_inc(link->master);
+		struct generic_pm_domain *master = link->master;
+
+		genpd_sd_counter_inc(master);
+
+		mutex_lock_nested(&master->lock, depth + 1);
+		ret = genpd_poweron(master, depth + 1);
+		mutex_unlock(&master->lock);
 
-		ret = genpd_poweron(link->master);
 		if (ret) {
-			genpd_sd_counter_dec(link->master);
+			genpd_sd_counter_dec(master);
 			goto err;
 		}
 	}
@@ -223,20 +229,6 @@ static int __genpd_poweron(struct generic_pm_domain *genpd)
 	return ret;
 }
 
-/**
- * genpd_poweron - Restore power to a given PM domain and its masters.
- * @genpd: PM domain to power up.
- */
-static int genpd_poweron(struct generic_pm_domain *genpd)
-{
-	int ret;
-
-	mutex_lock(&genpd->lock);
-	ret = __genpd_poweron(genpd);
-	mutex_unlock(&genpd->lock);
-	return ret;
-}
-
 static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
 {
 	return GENPD_DEV_CALLBACK(genpd, int, save_state, dev);
@@ -484,7 +476,7 @@ static int pm_genpd_runtime_resume(struct device *dev)
 	}
 
 	mutex_lock(&genpd->lock);
-	ret = __genpd_poweron(genpd);
+	ret = genpd_poweron(genpd, 0);
 	mutex_unlock(&genpd->lock);
 
 	if (ret)
@@ -495,8 +487,13 @@ static int pm_genpd_runtime_resume(struct device *dev)
 	if (timed && runtime_pm)
 		time_start = ktime_get();
 
-	genpd_start_dev(genpd, dev);
-	genpd_restore_dev(genpd, dev);
+	ret = genpd_start_dev(genpd, dev);
+	if (ret)
+		goto err_poweroff;
+
+	ret = genpd_restore_dev(genpd, dev);
+	if (ret)
+		goto err_stop;
 
 	/* Update resume latency value if the measured time exceeds it. */
 	if (timed && runtime_pm) {
@@ -511,6 +508,17 @@ static int pm_genpd_runtime_resume(struct device *dev)
 	}
 
 	return 0;
+
+err_stop:
+	genpd_stop_dev(genpd, dev);
+err_poweroff:
+	if (!dev->power.irq_safe) {
+		mutex_lock(&genpd->lock);
+		genpd_poweroff(genpd, 0);
+		mutex_unlock(&genpd->lock);
+	}
+
+	return ret;
 }
 
 static bool pd_ignore_unused;
@@ -595,6 +603,8 @@ static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
 	    || atomic_read(&genpd->sd_count) > 0)
 		return;
 
+	/* Choose the deepest state when suspending */
+	genpd->state_idx = genpd->state_count - 1;
 	genpd_power_off(genpd, timed);
 
 	genpd->status = GPD_STATE_POWER_OFF;
@@ -1339,8 +1349,8 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 	if (!link)
 		return -ENOMEM;
 
-	mutex_lock(&genpd->lock);
-	mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
+	mutex_lock(&subdomain->lock);
+	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
 
 	if (genpd->status == GPD_STATE_POWER_OFF
 	    &&  subdomain->status != GPD_STATE_POWER_OFF) {
@@ -1363,8 +1373,8 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 		genpd_sd_counter_inc(genpd);
 
  out:
-	mutex_unlock(&subdomain->lock);
 	mutex_unlock(&genpd->lock);
+	mutex_unlock(&subdomain->lock);
 	if (ret)
 		kfree(link);
 	return ret;
@@ -1385,9 +1395,10 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
 		return -EINVAL;
 
-	mutex_lock(&genpd->lock);
+	mutex_lock(&subdomain->lock);
+	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
 
-	if (!list_empty(&subdomain->slave_links) || subdomain->device_count) {
+	if (!list_empty(&subdomain->master_links) || subdomain->device_count) {
 		pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
 			subdomain->name);
 		ret = -EBUSY;
@@ -1398,22 +1409,19 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 		if (link->slave != subdomain)
 			continue;
 
-		mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
-
 		list_del(&link->master_node);
 		list_del(&link->slave_node);
 		kfree(link);
 		if (subdomain->status != GPD_STATE_POWER_OFF)
 			genpd_sd_counter_dec(genpd);
 
-		mutex_unlock(&subdomain->lock);
-
 		ret = 0;
 		break;
 	}
 
 out:
 	mutex_unlock(&genpd->lock);
+	mutex_unlock(&subdomain->lock);
 
 	return ret;
 }
@@ -1520,6 +1528,20 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
 		genpd->dev_ops.start = pm_clk_resume;
 	}
 
+	if (genpd->state_idx >= GENPD_MAX_NUM_STATES) {
+		pr_warn("Initial state index out of bounds.\n");
+		genpd->state_idx = GENPD_MAX_NUM_STATES - 1;
+	}
+
+	if (genpd->state_count > GENPD_MAX_NUM_STATES) {
+		pr_warn("Limiting states to  %d\n", GENPD_MAX_NUM_STATES);
+		genpd->state_count = GENPD_MAX_NUM_STATES;
+	}
+
+	/* Use only one "off" state if there were no states declared */
+	if (genpd->state_count == 0)
+		genpd->state_count = 1;
+
 	mutex_lock(&gpd_list_lock);
 	list_add(&genpd->gpd_list_node, &gpd_list);
 	mutex_unlock(&gpd_list_lock);
@@ -1680,6 +1702,9 @@ struct generic_pm_domain *of_genpd_get_from_provider(
 	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
 	struct of_genpd_provider *provider;
 
+	if (!genpdspec)
+		return ERR_PTR(-EINVAL);
+
 	mutex_lock(&of_genpd_mutex);
 
 	/* Check if we have such a provider in our array */
@@ -1818,8 +1843,10 @@ int genpd_dev_pm_attach(struct device *dev)
 
 	dev->pm_domain->detach = genpd_dev_pm_detach;
 	dev->pm_domain->sync = genpd_dev_pm_sync;
-	ret = genpd_poweron(pd);
 
+	mutex_lock(&pd->lock);
+	ret = genpd_poweron(pd, 0);
+	mutex_unlock(&pd->lock);
 out:
 	return ret ? -EPROBE_DEFER : 0;
 }
@@ -1874,6 +1901,7 @@ static int pm_genpd_summary_one(struct seq_file *s,
 	struct pm_domain_data *pm_data;
 	const char *kobj_path;
 	struct gpd_link *link;
+	char state[16];
 	int ret;
 
 	ret = mutex_lock_interruptible(&genpd->lock);
@@ -1882,7 +1910,13 @@ static int pm_genpd_summary_one(struct seq_file *s,
 
 	if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
 		goto exit;
-	seq_printf(s, "%-30s  %-15s ", genpd->name, status_lookup[genpd->status]);
+	if (genpd->status == GPD_STATE_POWER_OFF)
+		snprintf(state, sizeof(state), "%s-%u",
+			 status_lookup[genpd->status], genpd->state_idx);
+	else
+		snprintf(state, sizeof(state), "%s",
+			 status_lookup[genpd->status]);
+	seq_printf(s, "%-30s  %-15s ", genpd->name, state);
 
 	/*
 	 * Modifications on the list require holding locks on both