[PATCH v7 01/37] sh: passing FDT address to kernel startup.

From: Yoshinori Sato <ysato@users.sourceforge.jp>
To: linux-sh@vger.kernel.org
Cc: "Yoshinori Sato" <ysato@users.sourceforge.jp>,
	"Damien Le Moal" <dlemoal@kernel.org>,
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Subject: [PATCH v7 01/37] sh: passing FDT address to kernel startup.
Date: Thu,  4 Apr 2024 13:59:26 +0900	[thread overview]
Message-ID: <58ead9bb7def6e12a46dd7ad2fee716dc17e44f7.1712205900.git.ysato@users.sourceforge.jp> (raw)
In-Reply-To: <cover.1712205900.git.ysato@users.sourceforge.jp>

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>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 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

