From: Joonyoung Shim <jy0922.shim@samsung.com>
Date: Wed, 8 Apr 2015 04:59:45 +0000 (+0900)
Subject: gpu: arm: midgard: add voltage scaling for devfreq
X-Git-Tag: submit/tizen/20150416.081342~9
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fee1984de9a9b7ae5c35519985f0292f24f950d5;p=platform%2Fkernel%2Flinux-exynos.git

gpu: arm: midgard: add voltage scaling for devfreq

Support voltage scaling of mali regulator for devfreq.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
---

diff --git a/drivers/gpu/arm/midgard/mali_kbase_devfreq.c b/drivers/gpu/arm/midgard/mali_kbase_devfreq.c
index 1191a7fba81e..0f738c55d1d9 100644
--- a/drivers/gpu/arm/midgard/mali_kbase_devfreq.c
+++ b/drivers/gpu/arm/midgard/mali_kbase_devfreq.c
@@ -23,21 +23,80 @@
 #ifdef CONFIG_DEVFREQ_THERMAL
 #include <linux/devfreq_cooling.h>
 #endif
+#include <linux/regulator/consumer.h>
 
 #include "mali_kbase_power_actor.h"
 
+static int kbase_devfreq_target_up(struct kbase_device *kbdev,
+				   unsigned long freq, unsigned long volt)
+{
+	unsigned int old_volt;
+	int err;
+
+	old_volt = regulator_get_voltage(kbdev->vdd);
+	if (old_volt < 0) {
+		dev_err(kbdev->dev, "failed to get voltage\n");
+		return old_volt;
+	}
+
+	err = regulator_set_voltage(kbdev->vdd, volt, volt);
+	if (err < 0) {
+		dev_err(kbdev->dev, "failed to set voltage\n");
+		return err;
+	}
+
+	err = clk_set_rate(kbdev->clock, freq);
+	if (err < 0) {
+		dev_err(kbdev->dev, "failed to set clock %lu\n", freq);
+		regulator_set_voltage(kbdev->vdd, old_volt, old_volt);
+		return err;
+	}
+
+	return 0;
+}
+
+static int kbase_devfreq_target_down(struct kbase_device *kbdev,
+				     unsigned long freq, unsigned long volt)
+{
+	unsigned int old_freq;
+	int err;
+
+	old_freq = clk_get_rate(kbdev->clock);
+	if (old_freq < 0) {
+		dev_err(kbdev->dev, "failed to get clock rate\n");
+		return old_freq;
+	}
+
+	err = clk_set_rate(kbdev->clock, freq);
+	if (err < 0) {
+		dev_err(kbdev->dev, "failed to set clock %lu\n", freq);
+		return err;
+	}
+
+	err = regulator_set_voltage(kbdev->vdd, volt, volt);
+	if (err < 0) {
+		dev_err(kbdev->dev, "failed to set voltage\n");
+		clk_set_rate(kbdev->clock, old_freq);
+		return err;
+	}
+
+	return 0;
+}
+
 static int
 kbase_devfreq_target(struct device *dev, unsigned long *target_freq, u32 flags)
 {
 	struct kbase_device *kbdev = dev_get_drvdata(dev);
 	struct dev_pm_opp *opp;
 	unsigned long freq = 0;
+	unsigned long volt;
 	int err;
 
 	freq = *target_freq;
 
 	rcu_read_lock();
 	opp = devfreq_recommended_opp(dev, &freq, flags);
+	volt = dev_pm_opp_get_voltage(opp);
 	rcu_read_unlock();
 	if (IS_ERR_OR_NULL(opp)) {
 		dev_err(dev, "Failed to get opp (%ld)\n", PTR_ERR(opp));
@@ -52,12 +111,13 @@ kbase_devfreq_target(struct device *dev, unsigned long *target_freq, u32 flags)
 		return 0;
 	}
 
-	err = clk_set_rate(kbdev->clock, freq);
-	if (err) {
-		dev_err(dev, "Failed to set clock %lu (target %lu)\n",
-				freq, *target_freq);
+	if (kbdev->freq < freq)
+		err = kbase_devfreq_target_up(kbdev, freq, volt);
+	else
+		err = kbase_devfreq_target_down(kbdev, freq, volt);
+
+	if (err < 0)
 		return err;
-	}
 
 	kbdev->freq = freq;
 	*target_freq = freq;