[PATCH V2 7/7] arm/imx6q: add cpufreq support

[richard.zhao@linaro.org (Richard Zhao)]

use cpu0 node property clock-frequency to check max frequency.

Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
---
 arch/arm/mach-imx/Kconfig        |    1 +
 arch/arm/mach-imx/Makefile       |    2 +-
 arch/arm/mach-imx/cpu_op-imx6q.c |   69 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+), 1 deletions(-)
 create mode 100644 arch/arm/mach-imx/cpu_op-imx6q.c

diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index fbd414b..21e472f 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -834,6 +834,7 @@ comment "i.MX6 family:"
 
 config SOC_IMX6Q
 	bool "i.MX6 Quad support"
+	select ARCH_HAS_CPUFREQ
 	select ARM_GIC
 	select CACHE_L2X0
 	select CPU_V7
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 9cf630a..2dfe4a7 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -72,7 +72,7 @@ AFLAGS_head-v7.o :=-Wa,-march=armv7-a
 obj-$(CONFIG_SMP) += platsmp.o
 obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
 obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o
-obj-$(CONFIG_SOC_IMX6Q) += clock-imx6q.o mach-imx6q.o pm-imx6q.o
+obj-$(CONFIG_SOC_IMX6Q) += clock-imx6q.o mach-imx6q.o pm-imx6q.o cpu_op-imx6q.o
 
 # i.MX5 based machines
 obj-$(CONFIG_MACH_MX51_BABBAGE) += mach-mx51_babbage.o
diff --git a/arch/arm/mach-imx/cpu_op-imx6q.c b/arch/arm/mach-imx/cpu_op-imx6q.c
new file mode 100644
index 0000000..d24e081
--- /dev/null
+++ b/arch/arm/mach-imx/cpu_op-imx6q.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/of.h>
+#include <mach/hardware.h>
+
+static int arm_max_freq_idx;
+
+/* operating point(op): 0 - 1GHz; 1 - 800MHz, 3 - 400MHz, 4  - 160MHz */
+static struct cpu_op mx6q_cpu_op[] = {
+	{
+		.cpu_rate = 996000000,
+		.cpu_voltage = 1225000,
+	},
+	{
+		.cpu_rate = 792000000,
+		.cpu_voltage = 1100000,
+	},
+	{
+		.cpu_rate = 396000000,
+		.cpu_voltage = 950000,
+	},
+	{
+		.cpu_rate = 198000000,
+		.cpu_voltage = 850000,
+	},
+};
+
+struct cpu_op *mx6q_get_cpu_op(int *op)
+{
+	struct device_node *cpu0;
+	u32 val;
+	int i;
+
+	cpu0 = of_find_node_by_path("/cpus/cpu at 0");
+	if (cpu0 && !of_property_read_u32(cpu0, "clock-frequency", &val)) {
+		for (i = 0; i < ARRAY_SIZE(mx6q_cpu_op); i++) {
+			if (val >= mx6q_cpu_op[i].cpu_rate) {
+				arm_max_freq_idx = i;
+				break;
+			}
+		}
+	}
+	if (cpu0)
+		of_node_put(cpu0);
+	*op = ARRAY_SIZE(mx6q_cpu_op) - arm_max_freq_idx;
+	return mx6q_cpu_op + arm_max_freq_idx;
+}
+
+static int __init mx6q_cpu_op_init(void)
+{
+	get_cpu_op = mx6q_get_cpu_op;
+	return 0;
+}
+
+core_initcall(mx6q_cpu_op_init);
-- 
1.7.5.4