From 101e8dfa2a8b045c6655bf2b3d6fba8d378453cd Mon Sep 17 00:00:00 2001
From: wdenk <wdenk>
Date: Mon, 4 Apr 2005 12:08:28 +0000
Subject: Fix timer code for ARM systems: make sure that udelay() does not
 reset timers so it's save to use udelay() in timeout code.

---
 cpu/arm1136/interrupts.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

(limited to 'cpu/arm1136')

diff --git a/cpu/arm1136/interrupts.c b/cpu/arm1136/interrupts.c
index c80d9a5d0..23236dcb0 100644
--- a/cpu/arm1136/interrupts.c
+++ b/cpu/arm1136/interrupts.c
@@ -254,6 +254,8 @@ ulong get_timer_masked (void)
 void udelay_masked (unsigned long usec)
 {
 	ulong tmo;
+	ulong endtime;
+	signed long diff;
 
 	if (usec >= 1000) {			/* if "big" number, spread normalization to seconds */
 		tmo = usec / 1000;		/* start to normalize for usec to ticks per sec */
@@ -263,9 +265,12 @@ void udelay_masked (unsigned long usec)
 		tmo = usec * CFG_HZ;
 		tmo /= (1000*1000);
 	}
-	reset_timer_masked ();		/* set "advancing" timestamp to 0, set lastinc vaule */
-	while (get_timer_masked () < tmo) /* wait for time stamp to overtake tick number.*/
-		/* NOP */;
+	endtime = get_timer_masked () + tmo;
+
+	do {
+		ulong now = get_timer_masked ();
+		diff = endtime - now;
+	} while (diff >= 0);
 }
 
 /*
-- 
cgit v1.2.3