openwrt-xburst/target/linux/coldfire/patches/028-mcfv4e_cache_ck_0_len.patch

From 679a5be6f06b909adccc9c588feb26bf6d6df402 Mon Sep 17 00:00:00 2001
From: Kurt Mahan <kmahan@freescale.com>
Date: Thu, 6 Dec 2007 16:40:39 -0700
Subject: [PATCH] Add zero length checking to cache routines.

LTIBName: mcfv4e-cache-ck-0-len
Signed-off-by: Kurt Mahan <kmahan@freescale.com>
---
 include/asm-m68k/cf_cacheflush.h |   14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)

--- a/include/asm-m68k/cf_cacheflush.h
+++ b/include/asm-m68k/cf_cacheflush.h
@@ -127,7 +127,9 @@ static inline void flush_bcache(void)
 static inline void cf_cache_clear(unsigned long paddr, int len)
 {
 	/* number of lines */
-	len =  (len + (CACHE_LINE_SIZE-1)) / CACHE_LINE_SIZE;
+	len = (len + (CACHE_LINE_SIZE-1)) / CACHE_LINE_SIZE;
+	if (len == 0)
+		return;
 
 	/* align on set boundary */
 	paddr &= 0xfffffff0;
@@ -161,7 +163,9 @@ static inline void cf_cache_clear(unsign
 static inline void cf_cache_push(unsigned long paddr, int len)
 {
 	/* number of lines */
-	len =  (len + (CACHE_LINE_SIZE-1)) / CACHE_LINE_SIZE;
+	len = (len + (CACHE_LINE_SIZE-1)) / CACHE_LINE_SIZE;
+	if (len == 0)
+		return;
 
 	/* align on set boundary */
 	paddr &= 0xfffffff0;
@@ -195,7 +199,9 @@ static inline void cf_cache_push(unsigne
 static inline void cf_cache_flush(unsigned long paddr, int len)
 {
 	/* number of lines */
-	len =  (len + (CACHE_LINE_SIZE-1)) / CACHE_LINE_SIZE;
+	len = (len + (CACHE_LINE_SIZE-1)) / CACHE_LINE_SIZE;
+	if (len == 0)
+		return;
 
 	/* align on set boundary */
 	paddr &= 0xfffffff0;
@@ -234,6 +240,8 @@ static inline void cf_cache_flush_range(
 	vstart &= 0xfffffff0;
 	vend = PAGE_ALIGN((vend + (CACHE_LINE_SIZE-1))) & 0xfffffff0;
 	len = vend - vstart;
+	if (len == 0)
+		return;
 	vstart = __pa(vstart);
 	vend = vstart + len;