From 4409b3959edf7fd41707f773640e74fdef096383 Mon Sep 17 00:00:00 2001
From: Andre Przywara <andre.przywara@arm.com>
Date: Thu, 29 Sep 2016 23:08:31 +0100
Subject: sunxi: fix udelay() implementation

Nah, compilers are way too clever these days to fall for those simple
delay loops, in fact the function resulted into a single "ret" to be
generated.
Use an inline assembly loop instead.
---
 plat/sun50iw1p1/sunxi_cpu_ops.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/plat/sun50iw1p1/sunxi_cpu_ops.c b/plat/sun50iw1p1/sunxi_cpu_ops.c
index 1fcff13..9db3a9e 100644
--- a/plat/sun50iw1p1/sunxi_cpu_ops.c
+++ b/plat/sun50iw1p1/sunxi_cpu_ops.c
@@ -61,18 +61,18 @@
  static unsigned int sun50i_prcm_base = SUN50I_PRCM_PBASE;
  static unsigned int sun50i_r_cpucfg_base = SUN50I_RCPUCFG_PBASE;
  extern bakery_lock_t plat_console_lock;
- void udelay(unsigned int delay)
- {
-	 unsigned int i, j;
 
+void udelay(unsigned int delay)
+{
 	if (!delay)
 		return;
 
-	 for (i=0; i<1000*delay; i++)
-	 {
-		 j+=i;
-	 }
- }
+	__asm__ volatile (
+		"1:\tsubs %0, %0, #1\n"
+		"\tb.ne	1b"
+		:: "r" (delay * 1000UL)
+	);
+}
 
 #ifdef SUNXI_CPUOPS_REAL_DELAY
 #define CPU_DELAY_SHORT		10
-- 
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