[PATCH v3 1/2] cpufreq / OPP: Allow boost frequency to be looked up from device tree

Thomas Abraham ta.omasab at gmail.com
Tue May 13 18:02:59 PDT 2014


From: Thomas Abraham <thomas.ab at samsung.com>

Commit 6f19efc0 ("cpufreq: Add boost frequency support in core") adds
support for CPU boost mode. This patch adds support for finding available
boost frequencies from device tree and marking them as usable in boost mode.

Cc: Nishanth Menon <nm at ti.com>
Cc: Lukasz Majewski <l.majewski at samsung.com>
Signed-off-by: Thomas Abraham <thomas.ab at samsung.com>
---
 drivers/cpufreq/cpufreq_opp.c |   39 +++++++++++++++++++++++++++++++++++++++
 1 files changed, 39 insertions(+), 0 deletions(-)

diff --git a/drivers/cpufreq/cpufreq_opp.c b/drivers/cpufreq/cpufreq_opp.c
index c0c6f4a..e3c97f3 100644
--- a/drivers/cpufreq/cpufreq_opp.c
+++ b/drivers/cpufreq/cpufreq_opp.c
@@ -19,6 +19,7 @@
 #include <linux/pm_opp.h>
 #include <linux/rcupdate.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 /**
  * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device
@@ -51,6 +52,10 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
 	struct cpufreq_frequency_table *freq_table = NULL;
 	int i, max_opps, ret = 0;
 	unsigned long rate;
+#ifdef CONFIG_CPU_FREQ_BOOST_SW
+	int j, len;
+	u32 *boost_freqs = NULL;
+#endif
 
 	rcu_read_lock();
 
@@ -82,6 +87,40 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
 
 	*table = &freq_table[0];
 
+#ifdef CONFIG_CPU_FREQ_BOOST_SW
+	if (of_find_property(dev->of_node, "boost-frequency", &len)) {
+		if (len == 0 || (len & (sizeof(u32) - 1)) != 0) {
+			dev_err(dev, "%s: invalid boost frequency\n", __func__);
+			ret = -EINVAL;
+			goto out;
+		}
+
+		boost_freqs = kzalloc(len, GFP_KERNEL);
+		if (!boost_freqs) {
+			dev_warn(dev, "%s: no memory for boost freq table\n",
+					__func__);
+			ret = -ENOMEM;
+			goto out;
+		}
+		of_property_read_u32_array(dev->of_node, "boost-frequency",
+			boost_freqs, len / sizeof(u32));
+	}
+
+	for (j = 0; j < len / sizeof(u32) && boost_freqs; j++) {
+		for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
+			if (boost_freqs[j] == freq_table[i].frequency) {
+				freq_table[i].flags |= CPUFREQ_BOOST_FREQ;
+				break;
+			}
+		}
+		if (freq_table[i].frequency == CPUFREQ_TABLE_END)
+			pr_err("%s: invalid boost frequency %d\n",
+				__func__, boost_freqs[j]);
+	}
+
+	kfree(boost_freqs);
+#endif
+
 out:
 	rcu_read_unlock();
 	if (ret)
-- 
1.7.4.4




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