1 files changed, 57 insertions, 0 deletions
diff --git a/arch/x86/um/delay.c b/arch/x86/um/delay.c
new file mode 100644
index 0000000000..8d510ceb43
--- /dev/null
+++ b/arch/x86/um/delay.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ * Mostly copied from arch/x86/lib/delay.c
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <asm/param.h>
+
+void __delay(unsigned long loops)
+{
+	asm volatile(
+		"test %0,%0\n"
+		"jz 3f\n"
+		"jmp 1f\n"
+
+		".align 16\n"
+		"1: jmp 2f\n"
+
+		".align 16\n"
+		"2: dec %0\n"
+		" jnz 2b\n"
+		"3: dec %0\n"
+
+		: /* we don't need output */
+		: "a" (loops)
+	);
+}
+EXPORT_SYMBOL(__delay);
+
+inline void __const_udelay(unsigned long xloops)
+{
+	int d0;
+
+	xloops *= 4;
+	asm("mull %%edx"
+		: "=d" (xloops), "=&a" (d0)
+		: "1" (xloops), "0"
+		(loops_per_jiffy * (HZ/4)));
+
+	__delay(++xloops);
+}
+EXPORT_SYMBOL(__const_udelay);
+
+void __udelay(unsigned long usecs)
+{
+	__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
+EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+	__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);