ARM: cache: add extra feature enable for tauros2

The extra feature may be used by SOCs are prefetch, burst8,
write buffer coalesce

Signed-off-by: Chao Xie <xiechao.mail@gmail.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>

arch/arm/include/asm/hardware/cache-tauros2.h

@@ -8,4 +8,7 @@
  * warranty of any kind, whether express or implied.
  */
 
-extern void __init tauros2_init(void);
+#define CACHE_TAUROS2_PREFETCH_ON	(1 << 0)
+#define CACHE_TAUROS2_LINEFILL_BURST8	(1 << 1)
+
+extern void __init tauros2_init(unsigned int features);

arch/arm/mm/cache-tauros2.c

@@ -145,21 +145,6 @@ static inline void __init write_extra_features(u32 u)
 	__asm__("mcr p15, 1, %0, c15, c1, 0" : : "r" (u));
 }
 
-static void __init disable_l2_prefetch(void)
-{
-	u32 u;
-
-	/*
-	 * Read the CPU Extra Features register and verify that the
-	 * Disable L2 Prefetch bit is set.
-	 */
-	u = read_extra_features();
-	if (!(u & 0x01000000)) {
-		printk(KERN_INFO "Tauros2: Disabling L2 prefetch.\n");
-		write_extra_features(u | 0x01000000);
-	}
-}
-
 static inline int __init cpuid_scheme(void)
 {
 	return !!((processor_id & 0x000f0000) == 0x000f0000);
@@ -188,11 +173,36 @@ static inline void __init write_actlr(u32 actlr)
 	__asm__("mcr p15, 0, %0, c1, c0, 1\n" : : "r" (actlr));
 }
 
-void __init tauros2_init(void)
+static void enable_extra_feature(unsigned int features)
+{
+	u32 u;
+
+	u = read_extra_features();
+
+	if (features & CACHE_TAUROS2_PREFETCH_ON)
+		u &= ~0x01000000;
+	else
+		u |= 0x01000000;
+	printk(KERN_INFO "Tauros2: %s L2 prefetch.\n",
+			(features & CACHE_TAUROS2_PREFETCH_ON)
+			? "Enabling" : "Disabling");
+
+	if (features & CACHE_TAUROS2_LINEFILL_BURST8)
+		u |= 0x00100000;
+	else
+		u &= ~0x00100000;
+	printk(KERN_INFO "Tauros2: %s line fill burt8.\n",
+			(features & CACHE_TAUROS2_LINEFILL_BURST8)
+			? "Enabling" : "Disabling");
+
+	write_extra_features(u);
+}
+
+void __init tauros2_init(unsigned int features)
 {
 	char *mode = NULL;
 
-	disable_l2_prefetch();
+	enable_extra_feature(features);
 
 #ifdef CONFIG_CPU_32v5
 	if ((processor_id & 0xff0f0000) == 0x56050000) {