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.

---
Changes in v2:
- Enable caches for all Tegra2 boards instead of just Nvidia ones

 arch/arm/cpu/armv7/tegra2/board.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

index 9061d18..a996b88 100644
@@ -86,3 +86,11 @@ int checkboard(void)
 	return 0;
 }
 #endif	/* CONFIG_DISPLAY_BOARDINFO */
+
+#ifndef CONFIG_SYS_DCACHE_OFF
+void enable_caches(void)
+{
+	/* Enable D-cache. I-cache is already enabled in start.S */
+	dcache_enable();
+}
+#endif

1.7.3.1