1 files changed, 61 insertions, 0 deletions
diff --git a/arch/h8300/kernel/head_ram.S b/arch/h8300/kernel/head_ram.S
new file mode 100644
index 000000000..dbf8429f5
--- /dev/null
+++ b/arch/h8300/kernel/head_ram.S
@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <linux/sys.h>
+#include <linux/init.h>
+#include <asm/unistd.h>
+#include <asm/setup.h>
+#include <asm/segment.h>
+#include <asm/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+
+#if defined(CONFIG_CPU_H8300H)
+	.h8300h
+#define SYSCR 0xfee012
+#define IRAMTOP 0xffff20
+#endif
+#if defined(CONFIG_CPU_H8S)
+	.h8300s
+#define INTCR 0xffff31
+#define IRAMTOP 0xffc000
+#endif
+
+	__HEAD
+	.global	_start
+_start:
+	mov.l	#IRAMTOP,sp
+	/* .bss clear */
+	mov.l	#_sbss,er5
+	mov.l	#_ebss,er4
+	sub.l	er5,er4
+	shlr	er4
+	shlr	er4
+	sub.l	er2,er2
+1:
+	mov.l	er2,@er5
+	adds	#4,er5
+	dec.l	#1,er4
+	bne	1b
+	jsr	@h8300_fdt_init
+
+	/* linux kernel start */
+#if defined(CONFIG_CPU_H8300H)
+	ldc	#0xd0,ccr	/* running kernel */
+	mov.l	#SYSCR,er0
+	bclr	#3,@er0
+#endif
+#if defined(CONFIG_CPU_H8S)
+	ldc	#0x07,exr
+	bclr	#4,@INTCR:8
+	bset	#5,@INTCR:8	/* Interrupt mode 2 */
+	ldc	#0x90,ccr	/* running kernel */
+#endif
+	mov.l	#init_thread_union,sp
+	add.l	#0x2000,sp
+	jsr	@start_kernel
+
+1:
+	bra	1b
+
+	.end