microblaze: Clear print messages for DTB passing via r7

It is necessary to zeroed r7 when r7 points to bad
dtb - this caused that we have correct messages
about compiled-in dtb or passing via r7

Signed-off-by: Michal Simek <monstr@monstr.eu>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/microblaze/kernel/head.S b/arch/microblaze/kernel/head.S
index 3c4d4a2803e2..e41c6ce2a7be 100644
--- a/arch/microblaze/kernel/head.S
+++ b/arch/microblaze/kernel/head.S
@@ -62,7 +62,10 @@ ENTRY(_start)
         beqi    r7, no_fdt_arg                  /* NULL pointer?  don't copy */
         lw      r11, r0, r7                     /* Does r7 point to a */
         rsubi   r11, r11, OF_DT_HEADER          /* valid FDT? */
+        beqi    r11, _prepare_copy_fdt
+        or      r7, r0, r0              /* clear R7 when not valid DTB */
         bnei    r11, no_fdt_arg                 /* No - get out of here */
+_prepare_copy_fdt:
         or      r11, r0, r0 /* incremment */
         ori     r4, r0, TOPHYS(_fdt_start)
         ori     r3, r0, (0x4000 - 4)