ARM: Orion: Set eth packet size csum offload limit

The mv643xx ethernet controller limits the packet size for the TX
checksum offloading. This patch sets this limits for Kirkwood and
Dove which have smaller limits that the default.

As a side note, this patch is an updated version of a patch sent some years
ago: http://lists.infradead.org/pipermail/linux-arm-kernel/2010-June/017320.html
which seems to have been lost.

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Cc: <stable@vger.kernel.org>
diff --git a/include/linux/mv643xx_eth.h b/include/linux/mv643xx_eth.h
index 51bf8ad..49258e0 100644
--- a/include/linux/mv643xx_eth.h
+++ b/include/linux/mv643xx_eth.h
@@ -15,6 +15,8 @@
 #define MV643XX_ETH_SIZE_REG_4		0x2224
 #define MV643XX_ETH_BASE_ADDR_ENABLE_REG	0x2290
 
+#define MV643XX_TX_CSUM_DEFAULT_LIMIT	0
+
 struct mv643xx_eth_shared_platform_data {
 	struct mbus_dram_target_info	*dram;
 	struct platform_device	*shared_smi;