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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/cpuidle/cpuidle-zynq.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/cpuidle/cpuidle-zynq.c')
-rw-r--r--kernel/drivers/cpuidle/cpuidle-zynq.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/kernel/drivers/cpuidle/cpuidle-zynq.c b/kernel/drivers/cpuidle/cpuidle-zynq.c
new file mode 100644
index 000000000..543292b1d
--- /dev/null
+++ b/kernel/drivers/cpuidle/cpuidle-zynq.c
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2012-2013 Xilinx
+ *
+ * CPU idle support for Xilinx Zynq
+ *
+ * based on arch/arm/mach-at91/cpuidle.c
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * 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,
+};
+
+module_platform_driver(zynq_cpuidle_driver);