dm: core: Add option to configure an offset for the address translation

Some platforms need to ability to configure an offset to the standard
addresses extracted from the device-tree. This patch allows this by
adding a function to DM to configure this offset (if needed).

Signed-off-by: Stefan Roese <sr@denx.de>
Acked-by: Simon Glass <sjg@chromium.org>
Cc: Simon Glass <sjg@chromium.org>
Fixed space before tab:
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/core/root.c b/drivers/core/root.c
index e7b1f24..13c2713 100644
--- a/drivers/core/root.c
+++ b/drivers/core/root.c
@@ -23,6 +23,10 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+struct root_priv {
+	fdt_addr_t translation_offset;	/* optional translation offset */
+};
+
 static const struct driver_info root_info = {
 	.name		= "root_driver",
 };
@@ -37,6 +41,22 @@
 	return gd->dm_root;
 }
 
+fdt_addr_t dm_get_translation_offset(void)
+{
+	struct udevice *root = dm_root();
+	struct root_priv *priv = dev_get_priv(root);
+
+	return priv->translation_offset;
+}
+
+void dm_set_translation_offset(fdt_addr_t offs)
+{
+	struct udevice *root = dm_root();
+	struct root_priv *priv = dev_get_priv(root);
+
+	priv->translation_offset = offs;
+}
+
 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
 void fix_drivers(void)
 {
@@ -228,6 +248,7 @@
 U_BOOT_DRIVER(root_driver) = {
 	.name	= "root_driver",
 	.id	= UCLASS_ROOT,
+	.priv_auto_alloc_size = sizeof(struct root_priv),
 };
 
 /* This is the root uclass */