Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / cpufreq / vexpress-spc-cpufreq.c

diff --git a/kernel/drivers/cpufreq/vexpress-spc-cpufreq.c b/kernel/drivers/cpufreq/vexpress-spc-cpufreq.c
new file mode 100644 (file)
index 0000000..433e93f
--- /dev/null
+++ b/kernel/drivers/cpufreq/vexpress-spc-cpufreq.c
@@ -0,0 +1,69 @@
+/*
+ * Versatile Express SPC CPUFreq Interface driver
+ *
+ * It provides necessary ops to arm_big_little cpufreq driver.
+ *
+ * Copyright (C) 2013 ARM Ltd.
+ * Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/types.h>
+
+#include "arm_big_little.h"
+
+static int ve_spc_init_opp_table(struct device *cpu_dev)
+{
+       /*
+        * platform specific SPC code must initialise the opp table
+        * so just check if the OPP count is non-zero
+        */
+       return dev_pm_opp_get_opp_count(cpu_dev) <= 0;
+}
+
+static int ve_spc_get_transition_latency(struct device *cpu_dev)
+{
+       return 1000000; /* 1 ms */
+}
+
+static struct cpufreq_arm_bL_ops ve_spc_cpufreq_ops = {
+       .name   = "vexpress-spc",
+       .get_transition_latency = ve_spc_get_transition_latency,
+       .init_opp_table = ve_spc_init_opp_table,
+};
+
+static int ve_spc_cpufreq_probe(struct platform_device *pdev)
+{
+       return bL_cpufreq_register(&ve_spc_cpufreq_ops);
+}
+
+static int ve_spc_cpufreq_remove(struct platform_device *pdev)
+{
+       bL_cpufreq_unregister(&ve_spc_cpufreq_ops);
+       return 0;
+}
+
+static struct platform_driver ve_spc_cpufreq_platdrv = {
+       .driver = {
+               .name   = "vexpress-spc-cpufreq",
+       },
+       .probe          = ve_spc_cpufreq_probe,
+       .remove         = ve_spc_cpufreq_remove,
+};
+module_platform_driver(ve_spc_cpufreq_platdrv);
+
+MODULE_LICENSE("GPL");