cpuidle: mvebu: Add initial CPU idle support for Armada 370/XP SoC

Add the wfi, cpu idle and cpu deep idle power states support for the
Armada XP SoCs.

All the latencies and the power consumption values used at the
"armada_370_xp_idle_driver" structure are preliminary and will be
modified in the future after running some measurements and analysis.

Based on the work of Nadav Haklai.

Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Link: https://lkml.kernel.org/r/1397488214-20685-11-git-send-email-gregory.clement@free-electrons.com
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397488214-20685-11-git-send-email-gregory.clement@free-electrons.com
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

3 files changed, 99 insertions, 0 deletions

diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index 97ccc31dbdd8..5bb94780d377 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -1,6 +1,11 @@
 #
 # ARM CPU Idle drivers
 #
+config ARM_ARMADA_370_XP_CPUIDLE
+        bool "CPU Idle Driver for Armada 370/XP family processors"
+        depends on ARCH_MVEBU
+        help
+          Select this to enable cpuidle on Armada 370/XP processors.
 
 config ARM_BIG_LITTLE_CPUIDLE
         bool "Support for ARM big.LITTLE processors"
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index f71ae1b373c5..9902d052bd87 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
 
 ##################################################################################
 # ARM SoC drivers
+obj-$(CONFIG_ARM_ARMADA_370_XP_CPUIDLE) += cpuidle-armada-370-xp.o
 obj-$(CONFIG_ARM_BIG_LITTLE_CPUIDLE)    += cpuidle-big_little.o
 obj-$(CONFIG_ARM_HIGHBANK_CPUIDLE)      += cpuidle-calxeda.o
 obj-$(CONFIG_ARM_KIRKWOOD_CPUIDLE)      += cpuidle-kirkwood.o
diff --git a/drivers/cpuidle/cpuidle-armada-370-xp.c b/drivers/cpuidle/cpuidle-armada-370-xp.c
new file mode 100644
index 000000000000..28587d0f3947
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-armada-370-xp.c
@@ -0,0 +1,93 @@
+/*
+ * Marvell Armada 370 and Armada XP SoC cpuidle driver
+ *
+ * Copyright (C) 2014 Marvell
+ *
+ * Nadav Haklai <nadavh@marvell.com>
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * Maintainer: Gregory CLEMENT <gregory.clement@free-electrons.com>
+ */
+
+#include <linux/cpu_pm.h>
+#include <linux/cpuidle.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/suspend.h>
+#include <linux/platform_device.h>
+#include <asm/cpuidle.h>
+
+#define ARMADA_370_XP_MAX_STATES        3
+#define ARMADA_370_XP_FLAG_DEEP_IDLE    0x10000
+
+static int (*armada_370_xp_cpu_suspend)(int);
+
+static int armada_370_xp_enter_idle(struct cpuidle_device *dev,
+                                struct cpuidle_driver *drv,
+                                int index)
+{
+        int ret;
+        bool deepidle = false;
+        cpu_pm_enter();
+
+        if (drv->states[index].flags & ARMADA_370_XP_FLAG_DEEP_IDLE)
+                deepidle = true;
+
+        ret = armada_370_xp_cpu_suspend(deepidle);
+        if (ret)
+                return ret;
+
+        cpu_pm_exit();
+
+        return index;
+}
+
+static struct cpuidle_driver armada_370_xp_idle_driver = {
+        .name                   = "armada_370_xp_idle",
+        .states[0]              = ARM_CPUIDLE_WFI_STATE,
+        .states[1]              = {
+                .enter                  = armada_370_xp_enter_idle,
+                .exit_latency           = 10,
+                .power_usage            = 50,
+                .target_residency       = 100,
+                .flags                  = CPUIDLE_FLAG_TIME_VALID,
+                .name                   = "MV CPU IDLE",
+                .desc                   = "CPU power down",
+        },
+        .states[2]              = {
+                .enter                  = armada_370_xp_enter_idle,
+                .exit_latency           = 100,
+                .power_usage            = 5,
+                .target_residency       = 1000,
+                .flags                  = CPUIDLE_FLAG_TIME_VALID |
+                                                ARMADA_370_XP_FLAG_DEEP_IDLE,
+                .name                   = "MV CPU DEEP IDLE",
+                .desc                   = "CPU and L2 Fabric power down",
+        },
+        .state_count = ARMADA_370_XP_MAX_STATES,
+};
+
+static int armada_370_xp_cpuidle_probe(struct platform_device *pdev)
+{
+
+        armada_370_xp_cpu_suspend = (void *)(pdev->dev.platform_data);
+        return cpuidle_register(&armada_370_xp_idle_driver, NULL);
+}
+
+static struct platform_driver armada_370_xp_cpuidle_plat_driver = {
+        .driver = {
+                .name = "cpuidle-armada-370-xp",
+                .owner = THIS_MODULE,
+        },
+        .probe = armada_370_xp_cpuidle_probe,
+};
+
+module_platform_driver(armada_370_xp_cpuidle_plat_driver);
+
+MODULE_AUTHOR("Gregory CLEMENT <gregory.clement@free-electrons.com>");
+MODULE_DESCRIPTION("Armada 370/XP cpu idle driver");
+MODULE_LICENSE("GPL");