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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/s390/lib/delay.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/s390/lib/delay.c')
-rw-r--r--arch/s390/lib/delay.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c
new file mode 100644
index 0000000000..be14c58cb9
--- /dev/null
+++ b/arch/s390/lib/delay.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Precise Delay Loops for S390
+ *
+ * Copyright IBM Corp. 1999, 2008
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
+ */
+
+#include <linux/processor.h>
+#include <linux/delay.h>
+#include <asm/div64.h>
+#include <asm/timex.h>
+
+void __delay(unsigned long loops)
+{
+ /*
+ * Loop 'loops' times. Callers must not assume a specific
+ * amount of time passes before this function returns.
+ */
+ asm volatile("0: brct %0,0b" : : "d" ((loops/2) + 1));
+}
+EXPORT_SYMBOL(__delay);
+
+static void delay_loop(unsigned long delta)
+{
+ unsigned long end;
+
+ end = get_tod_clock_monotonic() + delta;
+ while (!tod_after(get_tod_clock_monotonic(), end))
+ cpu_relax();
+}
+
+void __udelay(unsigned long usecs)
+{
+ delay_loop(usecs << 12);
+}
+EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+ nsecs <<= 9;
+ do_div(nsecs, 125);
+ delay_loop(nsecs);
+}
+EXPORT_SYMBOL(__ndelay);