[ARM] Kirkwood: support L2 writeback mode

This patch allows booting Kirkwood with the L2 in writeback mode,
by reading the WT override bit from the L2 config register and
passing that into the Feroceon L2 init routine, instead of assuming
that the WT override bit will always be set

Signed-off-by: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/arch/arm/mach-kirkwood/common.c b/arch/arm/mach-kirkwood/common.c
index e73384fbbba8..5938a3b33cdc 100644
--- a/arch/arm/mach-kirkwood/common.c
+++ b/arch/arm/mach-kirkwood/common.c
@@ -313,6 +313,11 @@ static char * __init kirkwood_id(void)
         return "unknown 88F6000 variant";
 }
 
+static int __init is_l2_writethrough(void)
+{
+        return !!(readl(L2_CONFIG_REG) & L2_WRITETHROUGH);
+}
+
 void __init kirkwood_init(void)
 {
         printk(KERN_INFO "Kirkwood: %s, TCLK=%d.\n",
@@ -321,6 +326,6 @@ void __init kirkwood_init(void)
         kirkwood_setup_cpu_mbus();
 
 #ifdef CONFIG_CACHE_FEROCEON_L2
-        feroceon_l2_init(1);
+        feroceon_l2_init(is_l2_writethrough());
 #endif
 }