Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / cpuidle / cpuidle-kirkwood.c

diff --git a/kernel/drivers/cpuidle/cpuidle-kirkwood.c b/kernel/drivers/cpuidle/cpuidle-kirkwood.c
new file mode 100644 (file)
index 0000000..d23d8f4
--- /dev/null
+++ b/kernel/drivers/cpuidle/cpuidle-kirkwood.c
@@ -0,0 +1,87 @@
+/*
+ * CPU idle Marvell Kirkwood SoCs
+ *
+ * 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.
+ *
+ * The cpu idle uses wait-for-interrupt and DDR self refresh in order
+ * to implement two idle states -
+ * #1 wait-for-interrupt
+ * #2 wait-for-interrupt and DDR self refresh
+ *
+ * Maintainer: Jason Cooper <jason@lakedaemon.net>
+ * Maintainer: Andrew Lunn <andrew@lunn.ch>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/cpuidle.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <asm/cpuidle.h>
+
+#define KIRKWOOD_MAX_STATES    2
+
+static void __iomem *ddr_operation_base;
+
+/* Actual code that puts the SoC in different idle states */
+static int kirkwood_enter_idle(struct cpuidle_device *dev,
+                              struct cpuidle_driver *drv,
+                              int index)
+{
+       writel(0x7, ddr_operation_base);
+       cpu_do_idle();
+
+       return index;
+}
+
+static struct cpuidle_driver kirkwood_idle_driver = {
+       .name                   = "kirkwood_idle",
+       .owner                  = THIS_MODULE,
+       .states[0]              = ARM_CPUIDLE_WFI_STATE,
+       .states[1]              = {
+               .enter                  = kirkwood_enter_idle,
+               .exit_latency           = 10,
+               .target_residency       = 100000,
+               .name                   = "DDR SR",
+               .desc                   = "WFI and DDR Self Refresh",
+       },
+       .state_count = KIRKWOOD_MAX_STATES,
+};
+
+/* Initialize CPU idle by registering the idle states */
+static int kirkwood_cpuidle_probe(struct platform_device *pdev)
+{
+       struct resource *res;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       ddr_operation_base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(ddr_operation_base))
+               return PTR_ERR(ddr_operation_base);
+
+       return cpuidle_register(&kirkwood_idle_driver, NULL);
+}
+
+static int kirkwood_cpuidle_remove(struct platform_device *pdev)
+{
+       cpuidle_unregister(&kirkwood_idle_driver);
+       return 0;
+}
+
+static struct platform_driver kirkwood_cpuidle_driver = {
+       .probe = kirkwood_cpuidle_probe,
+       .remove = kirkwood_cpuidle_remove,
+       .driver = {
+                  .name = "kirkwood_cpuidle",
+                  },
+};
+
+module_platform_driver(kirkwood_cpuidle_driver);
+
+MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
+MODULE_DESCRIPTION("Kirkwood cpu idle driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:kirkwood-cpuidle");