patch-2.4.20 linux-2.4.20/arch/x86_64/lib/delay.c

• Lines: 44
• Date: Thu Nov 28 15:53:12 2002
• Orig file: linux-2.4.19/arch/x86_64/lib/delay.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/arch/x86_64/lib/delay.c linux-2.4.20/arch/x86_64/lib/delay.c
@@ -0,0 +1,43 @@
+/*
+ *	Precise Delay Loops for i386
+ *
+ *	Copyright (C) 1993 Linus Torvalds
+ *	Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ *
+ *	The __delay function must _NOT_ be inlined as its execution time
+ *	depends wildly on alignment on many x86 processors. 
+ */
+
+#include <linux/config.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <asm/delay.h>
+
+#ifdef CONFIG_SMP
+#include <asm/smp.h>
+#endif
+
+void __delay(unsigned long loops)
+{
+#ifndef CONFIG_SIMNOW
+	unsigned long bclock, now;
+	
+	rdtscl(bclock);
+	do
+	{
+		rep_nop(); 
+		rdtscl(now);
+	}
+	while((now-bclock) < loops);
+#endif
+}
+
+inline void __const_udelay(unsigned long xloops)
+{
+        __delay(((xloops * current_cpu_data.loops_per_jiffy) >> 32) * HZ);
+}
+
+void __udelay(unsigned long usecs)
+{
+	__const_udelay(usecs * 0x000010c6);  /* 2**32 / 1000000 */
+}