lcd: Add support for flushing LCD fb from dcache after update

This provides an option for the LCD to flush the dcache after each update
(puts, scroll or clear).

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/include/lcd.h b/include/lcd.h
index 6a600ee..8f84741 100644
--- a/include/lcd.h
+++ b/include/lcd.h
@@ -57,6 +57,14 @@
 extern struct bmp_image *gunzip_bmp(unsigned long addr, unsigned long *lenp);
 extern int bmp_display(ulong addr, int x, int y);
 
+/**
+ * Set whether we need to flush the dcache when changing the LCD image. This
+ * defaults to off.
+ *
+ * @param flush		non-zero to flush cache after update, 0 to skip
+ */
+void lcd_set_flush_dcache(int flush);
+
 #if defined CONFIG_MPC823
 /*
  * LCD controller stucture for MPC823 CPU