R4 is caller saved in SH ABI.
Save it so it doesn't get corrupted until it's needed for initialization.

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
---
 arch/sh/boot/compressed/head_32.S | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/sh/boot/compressed/head_32.S b/arch/sh/boot/compressed/head_32.S
index 7bb168133dbb..6be59851122e 100644
--- a/arch/sh/boot/compressed/head_32.S
+++ b/arch/sh/boot/compressed/head_32.S
@@ -15,7 +15,8 @@ startup:
 	/* Load initial status register */
 	mov.l   init_sr, r1
 	ldc     r1, sr
-
+	/* Save FDT address */
+	mov	r4, r13
 	/* Move myself to proper location if necessary */
 	mova	1f, r0
 	mov.l	1f, r2
@@ -84,7 +85,7 @@ l1:
 	/* Jump to the start of the decompressed kernel */
 	mov.l	kernel_start_addr, r0
 	jmp	@r0
-	nop
+	 mov	r13, r4
 	
 	.align	2
 bss_start_addr:
-- 
2.39.2

On Tue, Jan 9, 2024 at 9:23 AM Yoshinori Sato
<ysato@users.sourceforge.jp> wrote:
> R4 is caller saved in SH ABI.
> Save it so it doesn't get corrupted until it's needed for initialization.
>
> Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>

My
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
on v3 is still valid.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds