initial_commit

1 files changed, 58 insertions, 0 deletions

diff --git a/arch/arm/plat-versatile/sched-clock.c b/arch/arm/plat-versatile/sched-clock.c
new file mode 100644
index 00000000..3d6a4c29
--- /dev/null
+++ b/arch/arm/plat-versatile/sched-clock.c
@@ -0,0 +1,58 @@
+/*
+ *  linux/arch/arm/plat-versatile/sched-clock.c
+ *
+ *  Copyright (C) 1999 - 2003 ARM Limited
+ *  Copyright (C) 2000 Deep Blue Solutions Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include <linux/io.h>
+#include <linux/sched.h>
+
+#include <asm/sched_clock.h>
+#include <plat/sched_clock.h>
+
+static DEFINE_CLOCK_DATA(cd);
+static void __iomem *ctr;
+
+/*
+ * Constants generated by clocks_calc_mult_shift(m, s, 24MHz, NSEC_PER_SEC, 60).
+ * This gives a resolution of about 41ns and a wrap period of about 178s.
+ */
+#define SC_MULT		2796202667u
+#define SC_SHIFT	26
+
+unsigned long long notrace sched_clock(void)
+{
+	if (ctr) {
+		u32 cyc = readl(ctr);
+		return cyc_to_fixed_sched_clock(&cd, cyc, (u32)~0,
+						SC_MULT, SC_SHIFT);
+	} else
+		return 0;
+}
+
+static void notrace versatile_update_sched_clock(void)
+{
+	u32 cyc = readl(ctr);
+	update_sched_clock(&cd, cyc, (u32)~0);
+}
+
+void __init versatile_sched_clock_init(void __iomem *reg, unsigned long rate)
+{
+	ctr = reg;
+	init_fixed_sched_clock(&cd, versatile_update_sched_clock,
+			       32, rate, SC_MULT, SC_SHIFT);
+}