summaryrefslogtreecommitdiffstats
path: root/drivers/cpuidle/cpuidle-zynq.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/cpuidle/cpuidle-zynq.c
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/cpuidle/cpuidle-zynq.c')
-rw-r--r--drivers/cpuidle/cpuidle-zynq.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-zynq.c b/drivers/cpuidle/cpuidle-zynq.c
new file mode 100644
index 000000000..a79610e72
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-zynq.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012-2013 Xilinx
+ *
+ * CPU idle support for Xilinx Zynq
+ *
+ * based on arch/arm/mach-at91/cpuidle.c
+ *
+ * The cpu idle uses wait-for-interrupt and RAM self refresh in order
+ * to implement two idle states -
+ * #1 wait-for-interrupt
+ * #2 wait-for-interrupt and RAM self refresh
+ *
+ * Maintainer: Michal Simek <michal.simek@xilinx.com>
+ */
+
+#include <linux/init.h>
+#include <linux/cpuidle.h>
+#include <linux/platform_device.h>
+#include <asm/cpuidle.h>
+
+#define ZYNQ_MAX_STATES 2
+
+/* Actual code that puts the SoC in different idle states */
+static int zynq_enter_idle(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int index)
+{
+ /* Add code for DDR self refresh start */
+ cpu_do_idle();
+
+ return index;
+}
+
+static struct cpuidle_driver zynq_idle_driver = {
+ .name = "zynq_idle",
+ .owner = THIS_MODULE,
+ .states = {
+ ARM_CPUIDLE_WFI_STATE,
+ {
+ .enter = zynq_enter_idle,
+ .exit_latency = 10,
+ .target_residency = 10000,
+ .name = "RAM_SR",
+ .desc = "WFI and RAM Self Refresh",
+ },
+ },
+ .safe_state_index = 0,
+ .state_count = ZYNQ_MAX_STATES,
+};
+
+/* Initialize CPU idle by registering the idle states */
+static int zynq_cpuidle_probe(struct platform_device *pdev)
+{
+ pr_info("Xilinx Zynq CpuIdle Driver started\n");
+
+ return cpuidle_register(&zynq_idle_driver, NULL);
+}
+
+static struct platform_driver zynq_cpuidle_driver = {
+ .driver = {
+ .name = "cpuidle-zynq",
+ },
+ .probe = zynq_cpuidle_probe,
+};
+builtin_platform_driver(zynq_cpuidle_driver);