1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-kirkwood.c b/drivers/cpuidle/cpuidle-kirkwood.c
new file mode 100644
index 0000000000..13bf743f88
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-kirkwood.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * CPU idle Marvell Kirkwood SoCs
+ *
+ * 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)
+{
+	ddr_operation_base = devm_platform_ioremap_resource(pdev, 0);
+	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");