tegra2: Enable data cache

This enables the data cache on Tegra2 boards.

As discussed on the list, this is better off in the Tegra2 cpu code than in a
particular vendor directory. We should be safe turning on the cache for all
Tegra2 boards.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>

arch/arm/cpu/armv7/tegra2/board.c

@@ -141,3 +141,11 @@ void board_init_uart_f(void)
 #endif
 	setup_uarts(uart_ids);
 }
+
+#ifndef CONFIG_SYS_DCACHE_OFF
+void enable_caches(void)
+{
+	/* Enable D-cache. I-cache is already enabled in start.S */
+	dcache_enable();
+}
+#endif