ARM: ux500: Add debugfs file to change cpufreq->QoS delay

cat /debugfs/prcmu/opp_cpufreq_delay
echo <delay in jiffies> > /debugfs/prcmu/opp_cpufreq_delay

ST-Ericsson ID: CR 323730

Change-Id: I5c3b976c63342d49b2d6c198510197757867c70b
Signed-off-by: Per Fransson <per.xx.fransson@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/18363
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Reviewed-by: Martin PERSSON <martin.persson@stericsson.com>

2 files changed, 66 insertions, 2 deletions

diff --git a/arch/arm/mach-ux500/prcmu-debug.c b/arch/arm/mach-ux500/prcmu-debug.c
index e39baa3a21f..942740b4a23 100644
--- a/arch/arm/mach-ux500/prcmu-debug.c
+++ b/arch/arm/mach-ux500/prcmu-debug.c
@@ -280,6 +280,37 @@ static int ddr_opp_read(struct seq_file *s, void *p)
 			"unknown", opp);
 }
 
+static int cpufreq_delay_read(struct seq_file *s, void *p)
+{
+	return seq_printf(s, "%lu\n", prcmu_qos_get_cpufreq_opp_delay());
+}
+
+static ssize_t cpufreq_delay_write(struct file *file,
+				   const char __user *user_buf,
+				   size_t count, loff_t *ppos)
+{
+
+	char buf[32];
+	ssize_t buf_size;
+	long unsigned int i;
+
+	/* Get userspace string and assure termination */
+	buf_size = min(count, (sizeof(buf)-1));
+	if (copy_from_user(buf, user_buf, buf_size))
+		return -EFAULT;
+	buf[buf_size] = 0;
+
+	if (strict_strtoul(buf, 0, &i) != 0)
+		return buf_size;
+
+	prcmu_qos_set_cpufreq_opp_delay(i);
+
+	pr_info("prcmu debug: changed delay between cpufreq change and QoS "
+		 "requirement to %lu.\n", i);
+
+	return buf_size;
+}
+
 static int arm_opp_open_file(struct inode *inode, struct file *file)
 {
 	return single_open(file, arm_opp_read, inode->i_private);
@@ -305,6 +336,11 @@ static int ddr_stats_open_file(struct inode *inode, struct file *file)
 	return single_open(file, ddr_stats_print, inode->i_private);
 }
 
+static int cpufreq_delay_open_file(struct inode *inode, struct file *file)
+{
+	return single_open(file, cpufreq_delay_read, inode->i_private);
+}
+
 static const struct file_operations arm_opp_fops = {
 	.open = arm_opp_open_file,
 	.read = seq_read,
@@ -347,6 +383,15 @@ static const struct file_operations ddr_stats_fops = {
 	.owner = THIS_MODULE,
 };
 
+static const struct file_operations cpufreq_delay_fops = {
+	.open = cpufreq_delay_open_file,
+	.write = cpufreq_delay_write,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+	.owner = THIS_MODULE,
+};
+
 static int setup_debugfs(void)
 {
 	struct dentry *dir;
@@ -381,6 +426,11 @@ static int setup_debugfs(void)
 	if (IS_ERR_OR_NULL(file))
 		goto fail;
 
+	file = debugfs_create_file("opp_cpufreq_delay", (S_IRUGO),
+				   dir, NULL, &cpufreq_delay_fops);
+	if (IS_ERR_OR_NULL(file))
+		goto fail;
+
 	return 0;
 fail:
 	if ((file == NULL) && (dir != NULL))
diff --git a/arch/arm/mach-ux500/prcmu-qos-power.c b/arch/arm/mach-ux500/prcmu-qos-power.c
index 1cd19d99975..a1fba3ffc38 100644
--- a/arch/arm/mach-ux500/prcmu-qos-power.c
+++ b/arch/arm/mach-ux500/prcmu-qos-power.c
@@ -92,6 +92,18 @@ static struct prcmu_qos_object *prcmu_qos_array[] = {
 
 static DEFINE_SPINLOCK(prcmu_qos_lock);
 
+static unsigned long cpufreq_opp_delay = HZ / 5;
+
+unsigned long prcmu_qos_get_cpufreq_opp_delay()
+{
+	return cpufreq_opp_delay;
+}
+
+void prcmu_qos_set_cpufreq_opp_delay(unsigned long n)
+{
+	cpufreq_opp_delay = n;
+}
+
 /* static helper function */
 static s32 max_compare(s32 v1, s32 v2)
 {
@@ -470,7 +482,8 @@ static int qos_delayed_cpufreq_notifier(struct notifier_block *nb,
 		 * one.
 		 */
 		if (new_ddr_target != cpufreq_requirement_set)
-			schedule_delayed_work(&qos_delayed_work_up, HZ/5);
+			schedule_delayed_work(&qos_delayed_work_up,
+					      cpufreq_opp_delay);
 	} else {
 		cancel_delayed_work_sync(&qos_delayed_work_up);
 		/*
@@ -478,7 +491,8 @@ static int qos_delayed_cpufreq_notifier(struct notifier_block *nb,
 		 * one.
 		 */
 		if (new_ddr_target != cpufreq_requirement_set)
-			schedule_delayed_work(&qos_delayed_work_down, HZ/5);
+			schedule_delayed_work(&qos_delayed_work_down,
+					      cpufreq_opp_delay);
 	}
 
 	return 0;