x86: Add support for CONFIG_OF_CONTROL

Allow a device tree to be provided through the standard mechanisms.

Signed-off-by: Gabe Black <gabeblack@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/init_helpers.c b/arch/x86/lib/init_helpers.c
index 3a62b2e..3eec9a6 100644
--- a/arch/x86/lib/init_helpers.c
+++ b/arch/x86/lib/init_helpers.c
@@ -171,3 +171,32 @@
 	puts("ready\n");
 	return 0;
 }
+
+#ifdef CONFIG_OF_CONTROL
+int find_fdt(void)
+{
+#ifdef CONFIG_OF_EMBED
+	/* Get a pointer to the FDT */
+	gd->fdt_blob = _binary_dt_dtb_start;
+#elif defined CONFIG_OF_SEPARATE
+	/* FDT is at end of image */
+	gd->fdt_blob = (void *)(_end_ofs + _TEXT_BASE);
+#endif
+	/* Allow the early environment to override the fdt address */
+	gd->fdt_blob = (void *)getenv_ulong("fdtcontroladdr", 16,
+						(uintptr_t)gd->fdt_blob);
+
+	return 0;
+}
+
+int prepare_fdt(void)
+{
+	/* For now, put this check after the console is ready */
+	if (fdtdec_prepare_fdt()) {
+		panic("** CONFIG_OF_CONTROL defined but no FDT - please see "
+			"doc/README.fdt-control");
+	}
+
+	return 0;
+}
+#endif