EDP: sysedp: Add mininimum budget control

Bug 1475120

Change-Id: I21be3f45e624412626b6f01f2ad04307f2911a8c
Signed-off-by: Steve Rogers <srogers@nvidia.com>
Reviewed-on: http://git-master/r/378467
Reviewed-by: Timo Alho <talho@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User

3 files changed, 44 insertions, 5 deletions

diff --git a/drivers/edp/sysedp.c b/drivers/edp/sysedp.c
index 2eee57fc9c7b..97ff75938a86 100644
--- a/drivers/edp/sysedp.c
+++ b/drivers/edp/sysedp.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2013-2014, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -31,6 +31,7 @@ LIST_HEAD(registered_consumers);
 static struct sysedp_platform_data *pdata;
 unsigned int avail_budget = 1000000;
 int margin;
+int min_budget;
 
 void sysedp_set_avail_budget(unsigned int power)
 {
@@ -57,7 +58,7 @@ void _sysedp_refresh(void)
 	}
 
 	limit = (int)avail_budget - pmax_sum - margin;
-	limit = limit >= 0 ? limit : 0;
+	limit = limit >= min_budget ? limit : min_budget;
 	oc_relax = pmax_sum - pthres_sum;
 	oc_relax = oc_relax >= 0 ? oc_relax : 0;
 
@@ -212,6 +213,7 @@ static int sysedp_probe(struct platform_device *pdev)
 		return -EINVAL;
 
 	margin = pdata->margin;
+	min_budget = (pdata->min_budget >= 0) ? min_budget : 0;
 	sysedp_init_sysfs();
 	sysedp_init_debugfs();
 	return 0;
diff --git a/drivers/edp/sysedp_debug.c b/drivers/edp/sysedp_debug.c
index 4cb321da5f0f..1e996d15efce 100644
--- a/drivers/edp/sysedp_debug.c
+++ b/drivers/edp/sysedp_debug.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2013-2014, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -38,7 +38,7 @@ static int sysedp_status_show(struct seq_file *file, void *data)
 	}
 
 	limit = (int)avail_budget - pmax_sum - margin;
-	limit = limit >= 0 ? limit : 0;
+	limit = limit >= min_budget ? limit : min_budget;
 	oc_relax = pmax_sum - pthres_sum;
 	oc_relax = oc_relax >= 0 ? oc_relax : 0;
 
@@ -46,6 +46,7 @@ static int sysedp_status_show(struct seq_file *file, void *data)
 	seq_printf(file, "  avail_budget     : %u\n", avail_budget);
 	seq_printf(file, "- pmax_sum         : %u\n", pmax_sum);
 	seq_printf(file, "- margin           : %d\n", margin);
+	seq_printf(file, "( minimum budget   : %d)\n", min_budget);
 	seq_printf(file, "= remaining (OC=1) : %d\n", limit);
 	seq_printf(file, "+ oc_relax         : %d\n", oc_relax);
 	seq_printf(file, "= remaining (OC=0) : %d\n", limit + oc_relax);
@@ -72,6 +73,36 @@ static const struct file_operations sysedp_status_fops = {
 	.read = seq_read,
 };
 
+
+static int sysedp_min_budget_set(void *data, u64 val)
+{
+	int old;
+
+	old = min_budget;
+	min_budget = (((int)val) < 0) ? 0 : (int)val;
+
+	if (old != min_budget) {
+		mutex_lock(&sysedp_lock);
+		/* Changes to min_budget require sysedp refresh */
+		_sysedp_refresh();
+		mutex_unlock(&sysedp_lock);
+	}
+
+	return 0;
+}
+
+
+static int sysedp_min_budget_get(void *data, u64 *val)
+{
+	*val = min_budget;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(sysedp_min_budget_fops,
+			sysedp_min_budget_get,
+			sysedp_min_budget_set, "%lld\n");
+
+
 void sysedp_init_debugfs(void)
 {
 	struct dentry *d;
@@ -93,4 +124,9 @@ void sysedp_init_debugfs(void)
 	d = debugfs_create_file("status", S_IRUGO, sysedp_debugfs_dir, NULL,
 				&sysedp_status_fops);
 	WARN_ON(IS_ERR_OR_NULL(d));
+
+	d = debugfs_create_file("min_budget", S_IRUGO | S_IWUSR,
+				sysedp_debugfs_dir, NULL,
+				&sysedp_min_budget_fops);
+	WARN_ON(IS_ERR_OR_NULL(d));
 }
diff --git a/drivers/edp/sysedp_internal.h b/drivers/edp/sysedp_internal.h
index 96c3d9a918a6..cb725ac1d3c3 100644
--- a/drivers/edp/sysedp_internal.h
+++ b/drivers/edp/sysedp_internal.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2013, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2012-2014, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -24,6 +24,7 @@ extern struct mutex sysedp_lock;
 extern struct dentry *edp_debugfs_dir;
 extern struct dentry *sysedp_debugfs_dir;
 extern int margin;
+extern int min_budget;
 extern unsigned int avail_budget;
 extern unsigned int consumer_sum;
 extern struct list_head registered_consumers;