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-rw-r--r--arch/arm/mach-shmobile/timer.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/timer.c b/arch/arm/mach-shmobile/timer.c
new file mode 100644
index 0000000000..2335311b5f
--- /dev/null
+++ b/arch/arm/mach-shmobile/timer.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SH-Mobile Timer
+ *
+ * Copyright (C) 2010 Magnus Damm
+ * Copyright (C) 2002 - 2009 Paul Mundt
+ */
+#include <linux/platform_device.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/of_address.h>
+
+#include "common.h"
+
+void __init shmobile_init_delay(void)
+{
+ struct device_node *np;
+ u32 max_freq = 0;
+
+ for_each_of_cpu_node(np) {
+ u32 freq;
+
+ if (!of_property_read_u32(np, "clock-frequency", &freq))
+ max_freq = max(max_freq, freq);
+ }
+
+ if (!max_freq)
+ return;
+
+ /*
+ * Calculate a worst-case loops-per-jiffy value
+ * based on maximum cpu core hz setting and the
+ * __delay() implementation in arch/arm/lib/delay.S.
+ *
+ * This will result in a longer delay than expected
+ * when the cpu core runs on lower frequencies.
+ */
+
+ if (!preset_lpj)
+ preset_lpj = max_freq / HZ;
+}