[PATCH 20/56] microblaze_v2: heartbeat file

monstr
2008-05-04T13:49:33Z

From: Michal Simek <monstr@monstr.eu>

Signed-off-by: Michal Simek <monstr@monstr.eu>
---
arch/microblaze/kernel/heartbeat.c | 37 ++++++++++++++++++++++++++++++++++++
1 files changed, 37 insertions(+), 0 deletions(-)
create mode 100644 arch/microblaze/kernel/heartbeat.c

diff --git a/arch/microblaze/kernel/heartbeat.c b/arch/microblaze/kernel/heartbeat.c
new file mode 100644
index 0000000..508b463
--- /dev/null
+++ b/arch/microblaze/kernel/heartbeat.c
@@ -0,0 +1,37 @@
+/*
+ * arch/microblaze/kernel/heartbeat.c
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ */
+
+#include <linux/sched.h>
+#include <asm/page.h>
+#include <asm/io.h>
+#include <asm/setup.h>
+
+void heartbeat(void)
+{
+ static unsigned int cnt, period, dist;
+
+ if (cnt == 0 || cnt == dist)
+ iowrite32(1, CONFIG_HEART_BEAT_ADDRESS);
+ else if (cnt == 7 || cnt == dist + 7)
+ iowrite32(0, CONFIG_HEART_BEAT_ADDRESS);
+
+ if (++cnt > period) {
+ cnt = 0;
+
+ /*
+ * The hyperbolic function below modifies the heartbeat period
+ * length in dependency of the current (5min) load. It goes
+ * through the points f(0)=126, f(1)=86, f(5)=51, f(inf)->30.
+ */
+ period = ((672 << FSHIFT) / (5 * avenrun[0] +
+ (7 << FSHIFT))) + 30;
+ dist = period / 4;
+ }
+}
--
1.5.4.GIT