arm: cache: Implement cache range check for v7

Add code to aid tracking down cache alignment issues.
In case DEBUG is defined in the cache.c, this code will
check alignment of each attempt to flush/invalidate data
cache and print a warning if the alignment is incorrect.
If DEBUG is not defined, this code is optimized out.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Tom Rini <trini@konsulko.com>

arch/arm/cpu/armv7/cache_v7.c

@@ -16,6 +16,23 @@
 #define ARMV7_DCACHE_CLEAN_INVAL_RANGE	4
 
 #ifndef CONFIG_SYS_DCACHE_OFF
+static int check_cache_range(unsigned long start, unsigned long stop)
+{
+	int ok = 1;
+
+	if (start & (CONFIG_SYS_CACHELINE_SIZE - 1))
+		ok = 0;
+
+	if (stop & (CONFIG_SYS_CACHELINE_SIZE - 1))
+		ok = 0;
+
+	if (!ok)
+		debug("CACHE: Misaligned operation at range [%08lx, %08lx]\n",
+			start, stop);
+
+	return ok;
+}
+
 /*
  * Write the level and type you want to Cache Size Selection Register(CSSELR)
  * to get size details from Current Cache Size ID Register(CCSIDR)
@@ -257,6 +274,8 @@ void flush_dcache_all(void)
  */
 void invalidate_dcache_range(unsigned long start, unsigned long stop)
 {
+	check_cache_range(start, stop);
+
 	v7_dcache_maint_range(start, stop, ARMV7_DCACHE_INVAL_RANGE);
 
 	v7_outer_cache_inval_range(start, stop);
@@ -269,6 +288,8 @@ void invalidate_dcache_range(unsigned long start, unsigned long stop)
  */
 void flush_dcache_range(unsigned long start, unsigned long stop)
 {
+	check_cache_range(start, stop);
+
 	v7_dcache_maint_range(start, stop, ARMV7_DCACHE_CLEAN_INVAL_RANGE);
 
 	v7_outer_cache_flush_range(start, stop);