v4.19.13 snapshot.
diff --git a/arch/h8300/kernel/Makefile b/arch/h8300/kernel/Makefile
new file mode 100644
index 0000000..307aa51
--- /dev/null
+++ b/arch/h8300/kernel/Makefile
@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the linux kernel.
+#
+
+extra-y := vmlinux.lds
+
+obj-y := process.o traps.o ptrace.o \
+	 signal.o setup.o syscalls.o \
+	 irq.o entry.o
+
+obj-$(CONFIG_ROMKERNEL) += head_rom.o
+obj-$(CONFIG_RAMKERNEL) += head_ram.o
+
+obj-$(CONFIG_MODULES) += module.o h8300_ksyms.o
+obj-$(CONFIG_H8300H_SIM) += sim-console.o
+obj-$(CONFIG_H8S_SIM) += sim-console.o
+
+obj-$(CONFIG_CPU_H8300H) += ptrace_h.o
+obj-$(CONFIG_CPU_H8S) += ptrace_s.o
+
+obj-$(CONFIG_KGDB) += kgdb.o
diff --git a/arch/h8300/kernel/asm-offsets.c b/arch/h8300/kernel/asm-offsets.c
new file mode 100644
index 0000000..85e6050
--- /dev/null
+++ b/arch/h8300/kernel/asm-offsets.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This program is used to generate definitions needed by
+ * assembly language modules.
+ *
+ * We use the technique used in the OSF Mach kernel code:
+ * generate asm statements containing #defines,
+ * compile this file to assembler, and then extract the
+ * #defines from the assembly-language output.
+ */
+
+#include <linux/stddef.h>
+#include <linux/sched.h>
+#include <linux/kernel_stat.h>
+#include <linux/ptrace.h>
+#include <linux/hardirq.h>
+#include <linux/kbuild.h>
+#include <asm/irq.h>
+#include <asm/ptrace.h>
+
+int main(void)
+{
+	/* offsets into the task struct */
+	OFFSET(TASK_STATE, task_struct, state);
+	OFFSET(TASK_FLAGS, task_struct, flags);
+	OFFSET(TASK_PTRACE, task_struct, ptrace);
+	OFFSET(TASK_BLOCKED, task_struct, blocked);
+	OFFSET(TASK_THREAD, task_struct, thread);
+	OFFSET(TASK_THREAD_INFO, task_struct, stack);
+	OFFSET(TASK_MM, task_struct, mm);
+	OFFSET(TASK_ACTIVE_MM, task_struct, active_mm);
+
+	/* offsets into the irq_cpustat_t struct */
+	DEFINE(CPUSTAT_SOFTIRQ_PENDING, offsetof(irq_cpustat_t,
+						 __softirq_pending));
+
+	/* offsets into the thread struct */
+	OFFSET(THREAD_KSP, thread_struct, ksp);
+	OFFSET(THREAD_USP, thread_struct, usp);
+	OFFSET(THREAD_CCR, thread_struct, ccr);
+
+	/* offsets into the pt_regs struct */
+	DEFINE(LER0,  offsetof(struct pt_regs, er0)      - sizeof(long));
+	DEFINE(LER1,  offsetof(struct pt_regs, er1)      - sizeof(long));
+	DEFINE(LER2,  offsetof(struct pt_regs, er2)      - sizeof(long));
+	DEFINE(LER3,  offsetof(struct pt_regs, er3)      - sizeof(long));
+	DEFINE(LER4,  offsetof(struct pt_regs, er4)      - sizeof(long));
+	DEFINE(LER5,  offsetof(struct pt_regs, er5)      - sizeof(long));
+	DEFINE(LER6,  offsetof(struct pt_regs, er6)      - sizeof(long));
+	DEFINE(LORIG, offsetof(struct pt_regs, orig_er0) - sizeof(long));
+	DEFINE(LSP,   offsetof(struct pt_regs, sp)       - sizeof(long));
+	DEFINE(LCCR,  offsetof(struct pt_regs, ccr)      - sizeof(long));
+	DEFINE(LVEC,  offsetof(struct pt_regs, vector)   - sizeof(long));
+#if defined(CONFIG_CPU_H8S)
+	DEFINE(LEXR,  offsetof(struct pt_regs, exr)      - sizeof(long));
+#endif
+	DEFINE(LRET,  offsetof(struct pt_regs, pc)       - sizeof(long));
+
+	DEFINE(PT_PTRACED, PT_PTRACED);
+
+	/* offsets in thread_info structure */
+	OFFSET(TI_TASK, thread_info, task);
+	OFFSET(TI_FLAGS, thread_info, flags);
+	OFFSET(TI_CPU, thread_info, cpu);
+	OFFSET(TI_PRE, thread_info, preempt_count);
+
+	return 0;
+}
diff --git a/arch/h8300/kernel/entry.S b/arch/h8300/kernel/entry.S
new file mode 100644
index 0000000..4ade5f8
--- /dev/null
+++ b/arch/h8300/kernel/entry.S
@@ -0,0 +1,434 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *
+ *  linux/arch/h8300/kernel/entry.S
+ *
+ *  Yoshinori Sato <ysato@users.sourceforge.jp>
+ *  David McCullough <davidm@snapgear.com>
+ *
+ */
+
+/*
+ *  entry.S
+ *  include exception/interrupt gateway
+ *          system call entry
+ */
+
+#include <linux/sys.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)
+#define USERRET 8
+INTERRUPTS = 64
+	.h8300h
+	.macro	SHLL2 reg
+	shll.l	\reg
+	shll.l	\reg
+	.endm
+	.macro	SHLR2 reg
+	shlr.l	\reg
+	shlr.l	\reg
+	.endm
+	.macro	SAVEREGS
+	mov.l	er0,@-sp
+	mov.l	er1,@-sp
+	mov.l	er2,@-sp
+	mov.l	er3,@-sp
+	.endm
+	.macro	RESTOREREGS
+	mov.l	@sp+,er3
+	mov.l	@sp+,er2
+	.endm
+	.macro	SAVEEXR
+	.endm
+	.macro	RESTOREEXR
+	.endm
+#endif
+#if defined(CONFIG_CPU_H8S)
+#define USERRET 10
+#define USEREXR 8
+INTERRUPTS = 128
+	.h8300s
+	.macro	SHLL2 reg
+	shll.l	#2,\reg
+	.endm
+	.macro	SHLR2 reg
+	shlr.l	#2,\reg
+	.endm
+	.macro	SAVEREGS
+	stm.l	er0-er3,@-sp
+	.endm
+	.macro	RESTOREREGS
+	ldm.l	@sp+,er2-er3
+	.endm
+	.macro	SAVEEXR
+	mov.w	@(USEREXR:16,er0),r1
+	mov.w	r1,@(LEXR-LER3:16,sp)		/* copy EXR */
+	.endm
+	.macro	RESTOREEXR
+	mov.w	@(LEXR-LER1:16,sp),r1		/* restore EXR */
+	mov.b	r1l,r1h
+	mov.w	r1,@(USEREXR:16,er0)
+	.endm
+#endif
+
+
+/* CPU context save/restore macros. */
+
+	.macro	SAVE_ALL
+	mov.l	er0,@-sp
+	stc	ccr,r0l				/* check kernel mode */
+	btst	#4,r0l
+	bne	5f
+
+	/* user mode */
+	mov.l	sp,@_sw_usp
+	mov.l	@sp,er0				/* restore saved er0 */
+	orc	#0x10,ccr			/* switch kernel stack */
+	mov.l	@_sw_ksp,sp
+	sub.l	#(LRET-LORIG),sp		/* allocate LORIG - LRET */
+	SAVEREGS
+	mov.l   @_sw_usp,er0
+	mov.l   @(USERRET:16,er0),er1           /* copy the RET addr */
+	mov.l   er1,@(LRET-LER3:16,sp)
+	SAVEEXR
+
+	mov.l	@(LORIG-LER3:16,sp),er0
+	mov.l	er0,@(LER0-LER3:16,sp)		/* copy ER0 */
+	mov.w	e1,r1				/* e1 highbyte = ccr */
+	and	#0xef,r1h			/* mask mode? flag */
+	bra	6f
+5:
+	/* kernel mode */
+	mov.l	@sp,er0				/* restore saved er0 */
+	subs	#2,sp				/* set dummy ccr */
+	subs	#4,sp				/* set dummp sp */
+	SAVEREGS
+	mov.w	@(LRET-LER3:16,sp),r1		/* copy old ccr */
+6:
+	mov.b	r1h,r1l
+	mov.b	#0,r1h
+	mov.w	r1,@(LCCR-LER3:16,sp)		/* set ccr */
+	mov.l	@_sw_usp,er2
+	mov.l	er2,@(LSP-LER3:16,sp)		/* set usp */
+	mov.l	er6,@-sp			/* syscall arg #6 */
+	mov.l	er5,@-sp			/* syscall arg #5 */
+	mov.l	er4,@-sp			/* syscall arg #4 */
+	.endm					/* r1 = ccr */
+
+	.macro	RESTORE_ALL
+	mov.l	@sp+,er4
+	mov.l	@sp+,er5
+	mov.l	@sp+,er6
+	RESTOREREGS
+	mov.w	@(LCCR-LER1:16,sp),r0		/* check kernel mode */
+	btst	#4,r0l
+	bne	7f
+
+	orc	#0xc0,ccr
+	mov.l	@(LSP-LER1:16,sp),er0
+	mov.l	@(LER0-LER1:16,sp),er1		/* restore ER0 */
+	mov.l	er1,@er0
+	RESTOREEXR
+	mov.w	@(LCCR-LER1:16,sp),r1		/* restore the RET addr */
+	mov.b	r1l,r1h
+	mov.b	@(LRET+1-LER1:16,sp),r1l
+	mov.w	r1,e1
+	mov.w	@(LRET+2-LER1:16,sp),r1
+	mov.l	er1,@(USERRET:16,er0)
+
+	mov.l	@sp+,er1
+	add.l	#(LRET-LER1),sp			/* remove LORIG - LRET */
+	mov.l	sp,@_sw_ksp
+	andc	#0xef,ccr			/* switch to user mode */
+	mov.l	er0,sp
+	bra	8f
+7:
+	mov.l	@sp+,er1
+	add.l	#10,sp
+8:
+	mov.l	@sp+,er0
+	adds	#4,sp				/* remove the sw created LVEC */
+	rte
+	.endm
+
+.globl _system_call
+.globl ret_from_exception
+.globl ret_from_fork
+.globl ret_from_kernel_thread
+.globl ret_from_interrupt
+.globl _interrupt_redirect_table
+.globl _sw_ksp,_sw_usp
+.globl _resume
+.globl _interrupt_entry
+.globl _trace_break
+.globl _nmi
+
+#if defined(CONFIG_ROMKERNEL)
+	.section .int_redirect,"ax"
+_interrupt_redirect_table:
+#if defined(CONFIG_CPU_H8300H)
+	.rept	7
+	.long	0
+	.endr
+#endif
+#if defined(CONFIG_CPU_H8S)
+	.rept	5
+	.long	0
+	.endr
+	jmp	@_trace_break
+	.long	0
+#endif
+
+	jsr	@_interrupt_entry		/* NMI */
+	jmp	@_system_call			/* TRAPA #0 (System call) */
+	.long	0
+#if defined(CONFIG_KGDB)
+	jmp	@_kgdb_trap
+#else
+	.long	0
+#endif
+	jmp	@_trace_break			/* TRAPA #3 (breakpoint) */
+	.rept	INTERRUPTS-12
+	jsr	@_interrupt_entry
+	.endr
+#endif
+#if defined(CONFIG_RAMKERNEL)
+.globl _interrupt_redirect_table
+	.section .bss
+_interrupt_redirect_table:
+	.space	4
+#endif
+
+	.section .text
+	.align	2
+_interrupt_entry:
+	SAVE_ALL
+/* r1l is saved ccr */
+	mov.l	sp,er0
+	add.l	#LVEC,er0
+	btst	#4,r1l
+	bne	1f
+	/* user LVEC */
+	mov.l	@_sw_usp,er0
+	adds	#4,er0
+1:
+	mov.l	@er0,er0			/* LVEC address */
+#if defined(CONFIG_ROMKERNEL)
+	sub.l	#_interrupt_redirect_table,er0
+#endif
+#if defined(CONFIG_RAMKERNEL)
+	mov.l	@_interrupt_redirect_table,er1
+	sub.l	er1,er0
+#endif
+	SHLR2	er0
+	dec.l	#1,er0
+	mov.l	sp,er1
+	subs	#4,er1				/* adjust ret_pc */
+#if defined(CONFIG_CPU_H8S)
+	orc	#7,exr
+#endif
+	jsr	@do_IRQ
+	jmp	@ret_from_interrupt
+
+_system_call:
+	subs	#4,sp				/* dummy LVEC */
+	SAVE_ALL
+	/* er0: syscall nr */
+	andc	#0xbf,ccr
+	mov.l	er0,er4
+
+	/* save top of frame */
+	mov.l	sp,er0
+	jsr	@set_esp0
+	andc	#0x3f,ccr
+	mov.l	sp,er2
+	and.w	#0xe000,r2
+	mov.l	@(TI_FLAGS:16,er2),er2
+	and.w	#_TIF_WORK_SYSCALL_MASK,r2
+	beq	1f
+	mov.l	sp,er0
+	jsr	@do_syscall_trace_enter
+1:
+	cmp.l	#__NR_syscalls,er4
+	bcc	badsys
+	SHLL2	er4
+	mov.l	#_sys_call_table,er0
+	add.l	er4,er0
+	mov.l	@er0,er4
+	beq	ret_from_exception:16
+	mov.l	@(LER1:16,sp),er0
+	mov.l	@(LER2:16,sp),er1
+	mov.l	@(LER3:16,sp),er2
+	jsr	@er4
+	mov.l	er0,@(LER0:16,sp)		/* save the return value */
+	mov.l	sp,er2
+	and.w	#0xe000,r2
+	mov.l	@(TI_FLAGS:16,er2),er2
+	and.w	#_TIF_WORK_SYSCALL_MASK,r2
+	beq	2f
+	mov.l	sp,er0
+	jsr	@do_syscall_trace_leave
+2:
+	orc	#0xc0,ccr
+	bra	resume_userspace
+
+badsys:
+	mov.l	#-ENOSYS,er0
+	mov.l	er0,@(LER0:16,sp)
+	bra	resume_userspace
+
+#if !defined(CONFIG_PREEMPT)
+#define resume_kernel restore_all
+#endif
+
+ret_from_exception:
+#if defined(CONFIG_PREEMPT)
+	orc	#0xc0,ccr
+#endif
+ret_from_interrupt:
+	mov.b	@(LCCR+1:16,sp),r0l
+	btst	#4,r0l
+	bne	resume_kernel:16	/* return from kernel */
+resume_userspace:
+	andc	#0xbf,ccr
+	mov.l	sp,er4
+	and.w	#0xe000,r4		/* er4 <- current thread info */
+	mov.l	@(TI_FLAGS:16,er4),er1
+	and.l	#_TIF_WORK_MASK,er1
+	beq	restore_all:8
+work_pending:
+	btst	#TIF_NEED_RESCHED,r1l
+	bne	work_resched:8
+	/* work notifysig */
+	mov.l	sp,er0
+	subs	#4,er0			/* er0: pt_regs */
+	jsr	@do_notify_resume
+	bra	resume_userspace:8
+work_resched:
+	mov.l	sp,er0
+	jsr	@set_esp0
+	jsr	@schedule
+	bra	resume_userspace:8
+restore_all:
+	RESTORE_ALL			/* Does RTE */
+
+#if defined(CONFIG_PREEMPT)
+resume_kernel:
+	mov.l	@(TI_PRE_COUNT:16,er4),er0
+	bne	restore_all:8
+need_resched:
+	mov.l	@(TI_FLAGS:16,er4),er0
+	btst	#TIF_NEED_RESCHED,r0l
+	beq	restore_all:8
+	mov.b	@(LCCR+1:16,sp),r0l	/* Interrupt Enabled? */
+	bmi	restore_all:8
+	mov.l	sp,er0
+	jsr	@set_esp0
+	jsr	@preempt_schedule_irq
+	bra	need_resched:8
+#endif
+
+ret_from_fork:
+	mov.l	er2,er0
+	jsr	@schedule_tail
+	jmp	@ret_from_exception
+
+ret_from_kernel_thread:
+	mov.l	er2,er0
+	jsr	@schedule_tail
+	mov.l	@(LER4:16,sp),er0
+	mov.l	@(LER5:16,sp),er1
+	jsr	@er1
+	jmp	@ret_from_exception
+
+_resume:
+	/*
+	 * Beware - when entering resume, offset of tss is in d1,
+	 * prev (the current task) is in a0, next (the new task)
+	 * is in a1 and d2.b is non-zero if the mm structure is
+	 * shared between the tasks, so don't change these
+	 * registers until their contents are no longer needed.
+	 */
+
+	/* save sr */
+	sub.w	r3,r3
+	stc	ccr,r3l
+	mov.w	r3,@(THREAD_CCR+2:16,er0)
+
+	/* disable interrupts */
+	orc	#0xc0,ccr
+	mov.l	@_sw_usp,er3
+	mov.l	er3,@(THREAD_USP:16,er0)
+	mov.l	sp,@(THREAD_KSP:16,er0)
+
+	/* Skip address space switching if they are the same. */
+	/* FIXME: what did we hack out of here, this does nothing! */
+
+	mov.l	@(THREAD_USP:16,er1),er0
+	mov.l	er0,@_sw_usp
+	mov.l	@(THREAD_KSP:16,er1),sp
+
+	/* restore status register */
+	mov.w	@(THREAD_CCR+2:16,er1),r3
+
+	ldc	r3l,ccr
+	rts
+
+_trace_break:
+	subs	#4,sp
+	SAVE_ALL
+	sub.l	er1,er1
+	dec.l	#1,er1
+	mov.l	er1,@(LORIG,sp)
+	mov.l	sp,er0
+	jsr	@set_esp0
+	mov.l	@_sw_usp,er0
+	mov.l	@er0,er1
+	mov.w	@(-2:16,er1),r2
+	cmp.w	#0x5730,r2
+	beq	1f
+	subs	#2,er1
+	mov.l	er1,@er0
+1:
+	and.w	#0xff,e1
+	mov.l	er1,er0
+	jsr	@trace_trap
+	jmp	@ret_from_exception
+
+_nmi:
+	subs	#4, sp
+	mov.l	er0, @-sp
+	mov.l	@_interrupt_redirect_table, er0
+	add.l	#8*4, er0
+	mov.l	er0, @(4,sp)
+	mov.l	@sp+, er0
+	jmp	@_interrupt_entry
+
+#if defined(CONFIG_KGDB)
+_kgdb_trap:
+	subs	#4,sp
+	SAVE_ALL
+	mov.l	sp,er0
+	add.l	#LRET,er0
+	mov.l	er0,@(LSP,sp)
+	jsr	@set_esp0
+	mov.l	sp,er0
+	subs	#4,er0
+	jsr	@h8300_kgdb_trap
+	jmp	@ret_from_exception
+#endif
+
+	.section	.bss
+_sw_ksp:
+	.space	4
+_sw_usp:
+	.space	4
+
+	.end
diff --git a/arch/h8300/kernel/h8300_ksyms.c b/arch/h8300/kernel/h8300_ksyms.c
new file mode 100644
index 0000000..1c6f902
--- /dev/null
+++ b/arch/h8300/kernel/h8300_ksyms.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/module.h>
+#include <linux/linkage.h>
+
+/*
+ * libgcc functions - functions that are used internally by the
+ * compiler...  (prototypes are not correct though, but that
+ * doesn't really matter since they're not versioned).
+ */
+asmlinkage long __ucmpdi2(long long, long long);
+asmlinkage long long __ashldi3(long long, int);
+asmlinkage long long __ashrdi3(long long, int);
+asmlinkage long long __lshrdi3(long long, int);
+asmlinkage long __divsi3(long, long);
+asmlinkage long __modsi3(long, long);
+asmlinkage unsigned long __umodsi3(unsigned long, unsigned long);
+asmlinkage long long __muldi3(long long, long long);
+asmlinkage long __mulsi3(long, long);
+asmlinkage long __udivsi3(long, long);
+asmlinkage void *memcpy(void *, const void *, size_t);
+asmlinkage void *memset(void *, int, size_t);
+asmlinkage long strncpy_from_user(void *to, void *from, size_t n);
+
+	/* gcc lib functions */
+EXPORT_SYMBOL(__ucmpdi2);
+EXPORT_SYMBOL(__ashldi3);
+EXPORT_SYMBOL(__ashrdi3);
+EXPORT_SYMBOL(__lshrdi3);
+EXPORT_SYMBOL(__divsi3);
+EXPORT_SYMBOL(__modsi3);
+EXPORT_SYMBOL(__umodsi3);
+EXPORT_SYMBOL(__muldi3);
+EXPORT_SYMBOL(__mulsi3);
+EXPORT_SYMBOL(__udivsi3);
+EXPORT_SYMBOL(memcpy);
+EXPORT_SYMBOL(memset);
+EXPORT_SYMBOL(strncpy_from_user);
diff --git a/arch/h8300/kernel/head_ram.S b/arch/h8300/kernel/head_ram.S
new file mode 100644
index 0000000..dbf8429
--- /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
diff --git a/arch/h8300/kernel/head_rom.S b/arch/h8300/kernel/head_rom.S
new file mode 100644
index 0000000..ab55a9c
--- /dev/null
+++ b/arch/h8300/kernel/head_rom.S
@@ -0,0 +1,111 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/init.h>
+#include <asm/thread_info.h>
+
+#if defined(CONFIG_CPU_H8300H)
+	.h8300h
+#define SYSCR 0xfee012
+#define IRAMTOP 0xffff20
+#define NR_INT 64
+#endif
+#if defined(CONFIG_CPU_H8S)
+	.h8300s
+#define INTCR 0xffff31
+#define IRAMTOP 0xffc000
+#define NR_INT 128
+#endif
+
+	__HEAD
+	.global	_start
+_start:
+	mov.l	#IRAMTOP,sp
+#if !defined(CONFIG_H8300H_SIM) && \
+    !defined(CONFIG_H8S_SIM)
+	jsr	@lowlevel_init
+
+	/* copy .data */
+	mov.l	#_begin_data,er5
+	mov.l	#_sdata,er6
+	mov.l	#_edata,er4
+	sub.l	er6,er4
+	shlr.l	er4
+	shlr.l	er4
+1:
+	mov.l	@er5+,er0
+	mov.l	er0,@er6
+	adds	#4,er6
+	dec.l	#1,er4
+	bne	1b
+	/* .bss clear */
+	mov.l	#_sbss,er5
+	mov.l	#_ebss,er4
+	sub.l	er5,er4
+	shlr	er4
+	shlr	er4
+	sub.l	er0,er0
+1:
+	mov.l	er0,@er5
+	adds	#4,er5
+	dec.l	#1,er4
+	bne	1b
+#else
+	/* get cmdline from gdb */
+	jsr	@0xcc
+	;; er0 - argc
+	;; er1 - argv
+	mov.l	#command_line,er3
+	adds	#4,er1
+	dec.l	#1,er0
+	beq	4f
+1:
+	mov.l	@er1+,er2
+2:
+	mov.b	@er2+,r4l
+	beq	3f
+	mov.b	r4l,@er3
+	adds	#1,er3
+	bra	2b
+3:
+	mov.b	#' ',r4l
+	mov.b	r4l,@er3
+	adds	#1,er3
+	dec.l	#1,er0
+	bne	1b
+	subs	#1,er3
+	mov.b	#0,r4l
+	mov.b	r4l,@er3
+4:
+#endif
+	sub.l	er0,er0
+	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
+
+#if defined(CONFIG_ROMKERNEL)
+	/* interrupt vector */
+	.section .vectors,"ax"
+	.long	_start
+	.long	_start
+vector	=	2
+	.rept	NR_INT - 2
+	.long	_interrupt_redirect_table+vector*4
+vector	=	vector + 1
+	.endr
+#endif
+	.end
diff --git a/arch/h8300/kernel/irq.c b/arch/h8300/kernel/irq.c
new file mode 100644
index 0000000..834e4d7
--- /dev/null
+++ b/arch/h8300/kernel/irq.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/arch/h8300/kernel/irq.c
+ *
+ * Copyright 2014-2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_irq.h>
+#include <asm/traps.h>
+
+#ifdef CONFIG_RAMKERNEL
+typedef void (*h8300_vector)(void);
+
+static const h8300_vector __initconst trap_table[] = {
+	0, 0, 0, 0,
+	_trace_break,
+	0, 0,
+	_nmi,
+	_system_call,
+	0, 0,
+	_trace_break,
+};
+
+static unsigned long __init *get_vector_address(void)
+{
+	unsigned long *rom_vector = CPU_VECTOR;
+	unsigned long base, tmp;
+	int vec_no;
+
+	base = rom_vector[EXT_IRQ0] & ADDR_MASK;
+
+	/* check romvector format */
+	for (vec_no = EXT_IRQ0 + 1; vec_no <= EXT_IRQ0+EXT_IRQS; vec_no++) {
+		if ((base+(vec_no - EXT_IRQ0)*4) !=
+		    (rom_vector[vec_no] & ADDR_MASK))
+			return NULL;
+	}
+
+	/* ramvector base address */
+	base -= EXT_IRQ0*4;
+
+	/* writerble? */
+	tmp = ~(*(volatile unsigned long *)base);
+	(*(volatile unsigned long *)base) = tmp;
+	if ((*(volatile unsigned long *)base) != tmp)
+		return NULL;
+	return (unsigned long *)base;
+}
+
+static void __init setup_vector(void)
+{
+	int i;
+	unsigned long *ramvec, *ramvec_p;
+	const h8300_vector *trap_entry;
+
+	ramvec = get_vector_address();
+	if (ramvec == NULL)
+		panic("interrupt vector serup failed.");
+	else
+		pr_debug("virtual vector at 0x%p\n", ramvec);
+
+	/* create redirect table */
+	ramvec_p = ramvec;
+	trap_entry = trap_table;
+	for (i = 0; i < NR_IRQS; i++) {
+		if (i < 12) {
+			if (*trap_entry)
+				*ramvec_p = VECTOR(*trap_entry);
+			ramvec_p++;
+			trap_entry++;
+		} else
+			*ramvec_p++ = REDIRECT(_interrupt_entry);
+	}
+	_interrupt_redirect_table = ramvec;
+}
+#else
+void setup_vector(void)
+{
+	/* noting do */
+}
+#endif
+
+void __init init_IRQ(void)
+{
+	setup_vector();
+	irqchip_init();
+}
+
+asmlinkage void do_IRQ(int irq)
+{
+	irq_enter();
+	generic_handle_irq(irq);
+	irq_exit();
+}
diff --git a/arch/h8300/kernel/kgdb.c b/arch/h8300/kernel/kgdb.c
new file mode 100644
index 0000000..1a1d30c
--- /dev/null
+++ b/arch/h8300/kernel/kgdb.c
@@ -0,0 +1,135 @@
+/*
+ * H8/300 KGDB support
+ *
+ * Copyright (C) 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/ptrace.h>
+#include <linux/kgdb.h>
+#include <linux/kdebug.h>
+#include <linux/io.h>
+
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
+	{ "er0", GDB_SIZEOF_REG, offsetof(struct pt_regs, er0) },
+	{ "er1", GDB_SIZEOF_REG, offsetof(struct pt_regs, er1) },
+	{ "er2", GDB_SIZEOF_REG, offsetof(struct pt_regs, er2) },
+	{ "er3", GDB_SIZEOF_REG, offsetof(struct pt_regs, er3) },
+	{ "er4", GDB_SIZEOF_REG, offsetof(struct pt_regs, er4) },
+	{ "er5", GDB_SIZEOF_REG, offsetof(struct pt_regs, er5) },
+	{ "er6", GDB_SIZEOF_REG, offsetof(struct pt_regs, er6) },
+	{ "sp", GDB_SIZEOF_REG, offsetof(struct pt_regs, sp) },
+	{ "ccr", GDB_SIZEOF_REG, offsetof(struct pt_regs, ccr) },
+	{ "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, pc) },
+	{ "cycles", GDB_SIZEOF_REG, -1 },
+#if defined(CONFIG_CPU_H8S)
+	{ "exr", GDB_SIZEOF_REG, offsetof(struct pt_regs, exr) },
+#endif
+	{ "tick", GDB_SIZEOF_REG, -1 },
+	{ "inst", GDB_SIZEOF_REG, -1 },
+};
+
+char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return NULL;
+
+	switch (regno) {
+	case GDB_CCR:
+#if defined(CONFIG_CPU_H8S)
+	case GDB_EXR:
+#endif
+		*(u32 *)mem = *(u16 *)((void *)regs +
+				       dbg_reg_def[regno].offset);
+		break;
+	default:
+		if (dbg_reg_def[regno].offset >= 0)
+			memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,
+			       dbg_reg_def[regno].size);
+		else
+			memset(mem, 0, dbg_reg_def[regno].size);
+		break;
+	}
+	return dbg_reg_def[regno].name;
+}
+
+int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return -EINVAL;
+
+	switch (regno) {
+	case GDB_CCR:
+#if defined(CONFIG_CPU_H8S)
+	case GDB_EXR:
+#endif
+		*(u16 *)((void *)regs +
+			 dbg_reg_def[regno].offset) = *(u32 *)mem;
+		break;
+	default:
+		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,
+		       dbg_reg_def[regno].size);
+	}
+	return 0;
+}
+
+asmlinkage void h8300_kgdb_trap(struct pt_regs *regs)
+{
+	regs->pc &= 0x00ffffff;
+	if (kgdb_handle_exception(10, SIGTRAP, 0, regs))
+		return;
+	if (*(u16 *)(regs->pc) == *(u16 *)&arch_kgdb_ops.gdb_bpt_instr)
+		regs->pc += BREAK_INSTR_SIZE;
+	regs->pc |= regs->ccr << 24;
+}
+
+void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
+{
+	memset((char *)gdb_regs, 0, NUMREGBYTES);
+	gdb_regs[GDB_SP] = p->thread.ksp;
+	gdb_regs[GDB_PC] = KSTK_EIP(p);
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+	regs->pc = pc;
+}
+
+int kgdb_arch_handle_exception(int vector, int signo, int err_code,
+				char *remcom_in_buffer, char *remcom_out_buffer,
+				struct pt_regs *regs)
+{
+	char *ptr;
+	unsigned long addr;
+
+	switch (remcom_in_buffer[0]) {
+	case 's':
+	case 'c':
+		/* handle the optional parameters */
+		ptr = &remcom_in_buffer[1];
+		if (kgdb_hex2long(&ptr, &addr))
+			regs->pc = addr;
+
+		return 0;
+	}
+
+	return -1; /* this means that we do not want to exit from the handler */
+}
+
+int kgdb_arch_init(void)
+{
+	return 0;
+}
+
+void kgdb_arch_exit(void)
+{
+	/* Nothing to do */
+}
+
+struct kgdb_arch arch_kgdb_ops = {
+	/* Breakpoint instruction: trapa #2 */
+	.gdb_bpt_instr = { 0x57, 0x20 },
+};
diff --git a/arch/h8300/kernel/module.c b/arch/h8300/kernel/module.c
new file mode 100644
index 0000000..cd802cc
--- /dev/null
+++ b/arch/h8300/kernel/module.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+
+int apply_relocate_add(Elf32_Shdr *sechdrs,
+		       const char *strtab,
+		       unsigned int symindex,
+		       unsigned int relsec,
+		       struct module *me)
+{
+	unsigned int i;
+	Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
+
+	pr_debug("Applying relocate section %u to %u\n", relsec,
+	       sechdrs[relsec].sh_info);
+	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
+		/* This is where to make the change */
+		uint32_t *loc =
+			(uint32_t *)(sechdrs[sechdrs[relsec].sh_info].sh_addr
+					     + rela[i].r_offset);
+		/* This is the symbol it is referring to.  Note that all
+		   undefined symbols have been resolved.  */
+		Elf32_Sym *sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+			+ ELF32_R_SYM(rela[i].r_info);
+		uint32_t v = sym->st_value + rela[i].r_addend;
+
+		switch (ELF32_R_TYPE(rela[i].r_info)) {
+		case R_H8_DIR24R8:
+			loc = (uint32_t *)((uint32_t)loc - 1);
+			*loc = (*loc & 0xff000000) | ((*loc & 0xffffff) + v);
+			break;
+		case R_H8_DIR24A8:
+			if (ELF32_R_SYM(rela[i].r_info))
+				*loc += v;
+			break;
+		case R_H8_DIR32:
+		case R_H8_DIR32A16:
+			*loc += v;
+			break;
+		case R_H8_PCREL16:
+			v -= (unsigned long)loc + 2;
+			if ((Elf32_Sword)v > 0x7fff ||
+			    (Elf32_Sword)v < -(Elf32_Sword)0x8000)
+				goto overflow;
+			else
+				*(unsigned short *)loc = v;
+			break;
+		case R_H8_PCREL8:
+			v -= (unsigned long)loc + 1;
+			if ((Elf32_Sword)v > 0x7f ||
+			    (Elf32_Sword)v < -(Elf32_Sword)0x80)
+				goto overflow;
+			else
+				*(unsigned char *)loc = v;
+			break;
+		default:
+			pr_err("module %s: Unknown relocation: %u\n",
+			       me->name, ELF32_R_TYPE(rela[i].r_info));
+			return -ENOEXEC;
+		}
+	}
+	return 0;
+ overflow:
+	pr_err("module %s: relocation offset overflow: %08x\n",
+	       me->name, rela[i].r_offset);
+	return -ENOEXEC;
+}
diff --git a/arch/h8300/kernel/process.c b/arch/h8300/kernel/process.c
new file mode 100644
index 0000000..e35cdf0
--- /dev/null
+++ b/arch/h8300/kernel/process.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/arch/h8300/kernel/process.c
+ *
+ * Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ *  Based on:
+ *
+ *  linux/arch/m68knommu/kernel/process.c
+ *
+ *  Copyright (C) 1998  D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
+ *                      Kenneth Albanowski <kjahds@kjahds.com>,
+ *                      The Silver Hammer Group, Ltd.
+ *
+ *  linux/arch/m68k/kernel/process.c
+ *
+ *  Copyright (C) 1995  Hamish Macdonald
+ *
+ *  68060 fixes by Jesper Skov
+ */
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/interrupt.h>
+#include <linux/reboot.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/rcupdate.h>
+
+#include <linux/uaccess.h>
+#include <asm/traps.h>
+#include <asm/setup.h>
+#include <asm/pgtable.h>
+
+void (*pm_power_off)(void) = NULL;
+EXPORT_SYMBOL(pm_power_off);
+
+asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
+
+/*
+ * The idle loop on an H8/300..
+ */
+void arch_cpu_idle(void)
+{
+	local_irq_enable();
+	__asm__("sleep");
+}
+
+void machine_restart(char *__unused)
+{
+	local_irq_disable();
+	__asm__("jmp @@0");
+}
+
+void machine_halt(void)
+{
+	local_irq_disable();
+	__asm__("sleep");
+	for (;;)
+		;
+}
+
+void machine_power_off(void)
+{
+	local_irq_disable();
+	__asm__("sleep");
+	for (;;)
+		;
+}
+
+void show_regs(struct pt_regs *regs)
+{
+	show_regs_print_info(KERN_DEFAULT);
+
+	pr_notice("\n");
+	pr_notice("PC: %08lx  Status: %02x\n",
+	       regs->pc, regs->ccr);
+	pr_notice("ORIG_ER0: %08lx ER0: %08lx ER1: %08lx\n",
+	       regs->orig_er0, regs->er0, regs->er1);
+	pr_notice("ER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx\n",
+	       regs->er2, regs->er3, regs->er4, regs->er5);
+	pr_notice("ER6' %08lx ", regs->er6);
+	if (user_mode(regs))
+		printk("USP: %08lx\n", rdusp());
+	else
+		printk("\n");
+}
+
+void flush_thread(void)
+{
+}
+
+int copy_thread(unsigned long clone_flags,
+		unsigned long usp, unsigned long topstk,
+		struct task_struct *p)
+{
+	struct pt_regs *childregs;
+
+	childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
+
+	if (unlikely(p->flags & PF_KTHREAD)) {
+		memset(childregs, 0, sizeof(struct pt_regs));
+		childregs->retpc = (unsigned long) ret_from_kernel_thread;
+		childregs->er4 = topstk; /* arg */
+		childregs->er5 = usp; /* fn */
+	}  else {
+		*childregs = *current_pt_regs();
+		childregs->er0 = 0;
+		childregs->retpc = (unsigned long) ret_from_fork;
+		p->thread.usp = usp ?: rdusp();
+	}
+	p->thread.ksp = (unsigned long)childregs;
+
+	return 0;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+	unsigned long fp, pc;
+	unsigned long stack_page;
+	int count = 0;
+
+	if (!p || p == current || p->state == TASK_RUNNING)
+		return 0;
+
+	stack_page = (unsigned long)p;
+	fp = ((struct pt_regs *)p->thread.ksp)->er6;
+	do {
+		if (fp < stack_page+sizeof(struct thread_info) ||
+		    fp >= 8184+stack_page)
+			return 0;
+		pc = ((unsigned long *)fp)[1];
+		if (!in_sched_functions(pc))
+			return pc;
+		fp = *(unsigned long *) fp;
+	} while (count++ < 16);
+	return 0;
+}
+
+/* generic sys_clone is not enough registers */
+asmlinkage int sys_clone(unsigned long __user *args)
+{
+	unsigned long clone_flags;
+	unsigned long  newsp;
+	uintptr_t parent_tidptr;
+	uintptr_t child_tidptr;
+
+	get_user(clone_flags, &args[0]);
+	get_user(newsp, &args[1]);
+	get_user(parent_tidptr, &args[2]);
+	get_user(child_tidptr, &args[3]);
+	return do_fork(clone_flags, newsp, 0,
+		       (int __user *)parent_tidptr, (int __user *)child_tidptr);
+}
diff --git a/arch/h8300/kernel/ptrace.c b/arch/h8300/kernel/ptrace.c
new file mode 100644
index 0000000..0dc1c8f
--- /dev/null
+++ b/arch/h8300/kernel/ptrace.c
@@ -0,0 +1,205 @@
+/*
+ *  linux/arch/h8300/kernel/ptrace.c
+ *
+ *  Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of
+ * this archive for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/audit.h>
+#include <linux/tracehook.h>
+#include <linux/regset.h>
+#include <linux/elf.h>
+
+#define CCR_MASK 0x6f    /* mode/imask not set */
+#define EXR_MASK 0x80    /* modify only T */
+
+#define PT_REG(r) offsetof(struct pt_regs, r)
+
+extern void user_disable_single_step(struct task_struct *child);
+
+/* Mapping from PT_xxx to the stack offset at which the register is
+   saved.  Notice that usp has no stack-slot and needs to be treated
+   specially (see get_reg/put_reg below). */
+static const int register_offset[] = {
+	PT_REG(er1), PT_REG(er2), PT_REG(er3), PT_REG(er4),
+	PT_REG(er5), PT_REG(er6), PT_REG(er0), -1,
+	PT_REG(orig_er0), PT_REG(ccr), PT_REG(pc),
+#if defined(CONFIG_CPU_H8S)
+	PT_REG(exr),
+#endif
+};
+
+/* read register */
+long h8300_get_reg(struct task_struct *task, int regno)
+{
+	switch (regno) {
+	case PT_USP:
+		return task->thread.usp + sizeof(long)*2;
+	case PT_CCR:
+	case PT_EXR:
+	    return *(unsigned short *)(task->thread.esp0 +
+				       register_offset[regno]);
+	default:
+	    return *(unsigned long *)(task->thread.esp0 +
+				      register_offset[regno]);
+	}
+}
+
+int h8300_put_reg(struct task_struct *task, int regno, unsigned long data)
+{
+	unsigned short oldccr;
+	unsigned short oldexr;
+
+	switch (regno) {
+	case PT_USP:
+		task->thread.usp = data - sizeof(long)*2;
+	case PT_CCR:
+		oldccr = *(unsigned short *)(task->thread.esp0 +
+					     register_offset[regno]);
+		oldccr &= ~CCR_MASK;
+		data &= CCR_MASK;
+		data |= oldccr;
+		*(unsigned short *)(task->thread.esp0 +
+				    register_offset[regno]) = data;
+		break;
+	case PT_EXR:
+		oldexr = *(unsigned short *)(task->thread.esp0 +
+					     register_offset[regno]);
+		oldccr &= ~EXR_MASK;
+		data &= EXR_MASK;
+		data |= oldexr;
+		*(unsigned short *)(task->thread.esp0 +
+				    register_offset[regno]) = data;
+		break;
+	default:
+		*(unsigned long *)(task->thread.esp0 +
+				   register_offset[regno]) = data;
+		break;
+	}
+	return 0;
+}
+
+static int regs_get(struct task_struct *target,
+		    const struct user_regset *regset,
+		    unsigned int pos, unsigned int count,
+		    void *kbuf, void __user *ubuf)
+{
+	int r;
+	struct user_regs_struct regs;
+	long *reg = (long *)&regs;
+
+	/* build user regs in buffer */
+	BUILD_BUG_ON(sizeof(regs) % sizeof(long) != 0);
+	for (r = 0; r < sizeof(regs) / sizeof(long); r++)
+		*reg++ = h8300_get_reg(target, r);
+
+	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+				   &regs, 0, sizeof(regs));
+}
+
+static int regs_set(struct task_struct *target,
+		    const struct user_regset *regset,
+		    unsigned int pos, unsigned int count,
+		    const void *kbuf, const void __user *ubuf)
+{
+	int r;
+	int ret;
+	struct user_regs_struct regs;
+	long *reg;
+
+	/* build user regs in buffer */
+	BUILD_BUG_ON(sizeof(regs) % sizeof(long) != 0);
+	for (reg = (long *)&regs, r = 0; r < sizeof(regs) / sizeof(long); r++)
+		*reg++ = h8300_get_reg(target, r);
+
+	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				 &regs, 0, sizeof(regs));
+	if (ret)
+		return ret;
+
+	/* write back to pt_regs */
+	for (reg = (long *)&regs, r = 0; r < sizeof(regs) / sizeof(long); r++)
+		h8300_put_reg(target, r, *reg++);
+	return 0;
+}
+
+enum h8300_regset {
+	REGSET_GENERAL,
+};
+
+static const struct user_regset h8300_regsets[] = {
+	[REGSET_GENERAL] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= ELF_NGREG,
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.get		= regs_get,
+		.set		= regs_set,
+	},
+};
+
+static const struct user_regset_view user_h8300_native_view = {
+	.name = "h8300",
+	.e_machine = EM_H8_300,
+	.regsets = h8300_regsets,
+	.n = ARRAY_SIZE(h8300_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+	return &user_h8300_native_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+	user_disable_single_step(child);
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+		 unsigned long addr, unsigned long data)
+{
+	int ret;
+
+	switch (request) {
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+	return ret;
+}
+
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
+{
+	long ret = 0;
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+	    tracehook_report_syscall_entry(regs))
+		/*
+		 * Tracing decided this syscall should not happen.
+		 * We'll return a bogus call number to get an ENOSYS
+		 * error, but leave the original number in regs->regs[0].
+		 */
+		ret = -1L;
+
+	audit_syscall_entry(regs->er1, regs->er2, regs->er3,
+			    regs->er4, regs->er5);
+
+	return ret ?: regs->er0;
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+	int step;
+
+	audit_syscall_exit(regs);
+
+	step = test_thread_flag(TIF_SINGLESTEP);
+	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+		tracehook_report_syscall_exit(regs, step);
+}
diff --git a/arch/h8300/kernel/ptrace_h.c b/arch/h8300/kernel/ptrace_h.c
new file mode 100644
index 0000000..f5ff3b7
--- /dev/null
+++ b/arch/h8300/kernel/ptrace_h.c
@@ -0,0 +1,256 @@
+/*
+ *    ptrace cpu depend helper functions
+ *
+ *  Copyright 2003, 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of
+ * this archive for more details.
+ */
+
+#include <linux/linkage.h>
+#include <linux/sched/signal.h>
+#include <asm/ptrace.h>
+
+#define BREAKINST 0x5730 /* trapa #3 */
+
+/* disable singlestep */
+void user_disable_single_step(struct task_struct *child)
+{
+	if ((long)child->thread.breakinfo.addr != -1L) {
+		*(child->thread.breakinfo.addr) = child->thread.breakinfo.inst;
+		child->thread.breakinfo.addr = (unsigned short *)-1L;
+	}
+}
+
+/* calculate next pc */
+enum jump_type {none,	 /* normal instruction */
+		jabs,	 /* absolute address jump */
+		ind,	 /* indirect address jump */
+		ret,	 /* return to subrutine */
+		reg,	 /* register indexed jump */
+		relb,	 /* pc relative jump (byte offset) */
+		relw,	 /* pc relative jump (word offset) */
+	       };
+
+/* opcode decode table define
+   ptn: opcode pattern
+   msk: opcode bitmask
+   len: instruction length (<0 next table index)
+   jmp: jump operation mode */
+struct optable {
+	unsigned char bitpattern;
+	unsigned char bitmask;
+	signed char length;
+	signed char type;
+} __packed __aligned(1);
+
+#define OPTABLE(ptn, msk, len, jmp)	\
+	{				\
+		.bitpattern = ptn,	\
+		.bitmask    = msk,	\
+		.length	    = len,	\
+		.type	    = jmp,	\
+	}
+
+static const struct optable optable_0[] = {
+	OPTABLE(0x00, 0xff,  1, none), /* 0x00 */
+	OPTABLE(0x01, 0xff, -1, none), /* 0x01 */
+	OPTABLE(0x02, 0xfe,  1, none), /* 0x02-0x03 */
+	OPTABLE(0x04, 0xee,  1, none), /* 0x04-0x05/0x14-0x15 */
+	OPTABLE(0x06, 0xfe,  1, none), /* 0x06-0x07 */
+	OPTABLE(0x08, 0xea,  1, none), /* 0x08-0x09/0x0c-0x0d/0x18-0x19/0x1c-0x1d */
+	OPTABLE(0x0a, 0xee,  1, none), /* 0x0a-0x0b/0x1a-0x1b */
+	OPTABLE(0x0e, 0xee,  1, none), /* 0x0e-0x0f/0x1e-0x1f */
+	OPTABLE(0x10, 0xfc,  1, none), /* 0x10-0x13 */
+	OPTABLE(0x16, 0xfe,  1, none), /* 0x16-0x17 */
+	OPTABLE(0x20, 0xe0,  1, none), /* 0x20-0x3f */
+	OPTABLE(0x40, 0xf0,  1, relb), /* 0x40-0x4f */
+	OPTABLE(0x50, 0xfc,  1, none), /* 0x50-0x53 */
+	OPTABLE(0x54, 0xfd,  1, ret), /* 0x54/0x56 */
+	OPTABLE(0x55, 0xff,  1, relb), /* 0x55 */
+	OPTABLE(0x57, 0xff,  1, none), /* 0x57 */
+	OPTABLE(0x58, 0xfb,  2, relw), /* 0x58/0x5c */
+	OPTABLE(0x59, 0xfb,  1, reg), /* 0x59/0x5b */
+	OPTABLE(0x5a, 0xfb,  2, jabs), /* 0x5a/0x5e */
+	OPTABLE(0x5b, 0xfb,  2, ind), /* 0x5b/0x5f */
+	OPTABLE(0x60, 0xe8,  1, none), /* 0x60-0x67/0x70-0x77 */
+	OPTABLE(0x68, 0xfa,  1, none), /* 0x68-0x69/0x6c-0x6d */
+	OPTABLE(0x6a, 0xfe, -2, none), /* 0x6a-0x6b */
+	OPTABLE(0x6e, 0xfe,  2, none), /* 0x6e-0x6f */
+	OPTABLE(0x78, 0xff,  4, none), /* 0x78 */
+	OPTABLE(0x79, 0xff,  2, none), /* 0x79 */
+	OPTABLE(0x7a, 0xff,  3, none), /* 0x7a */
+	OPTABLE(0x7b, 0xff,  2, none), /* 0x7b */
+	OPTABLE(0x7c, 0xfc,  2, none), /* 0x7c-0x7f */
+	OPTABLE(0x80, 0x80,  1, none), /* 0x80-0xff */
+};
+
+static const struct optable optable_1[] = {
+	OPTABLE(0x00, 0xff, -3, none), /* 0x0100 */
+	OPTABLE(0x40, 0xf0, -3, none), /* 0x0140-0x14f */
+	OPTABLE(0x80, 0xf0,  1, none), /* 0x0180-0x018f */
+	OPTABLE(0xc0, 0xc0,  2, none), /* 0x01c0-0x01ff */
+};
+
+static const struct optable optable_2[] = {
+	OPTABLE(0x00, 0x20,  2, none), /* 0x6a0?/0x6a8?/0x6b0?/0x6b8? */
+	OPTABLE(0x20, 0x20,  3, none), /* 0x6a2?/0x6aa?/0x6b2?/0x6ba? */
+};
+
+static const struct optable optable_3[] = {
+	OPTABLE(0x69, 0xfb,  2, none), /* 0x010069/0x01006d/014069/0x01406d */
+	OPTABLE(0x6b, 0xff, -4, none), /* 0x01006b/0x01406b */
+	OPTABLE(0x6f, 0xff,  3, none), /* 0x01006f/0x01406f */
+	OPTABLE(0x78, 0xff,  5, none), /* 0x010078/0x014078 */
+};
+
+static const struct optable optable_4[] = {
+/* 0x0100690?/0x01006d0?/0140690?/0x01406d0?/
+   0x0100698?/0x01006d8?/0140698?/0x01406d8? */
+	OPTABLE(0x00, 0x78, 3, none),
+/* 0x0100692?/0x01006d2?/0140692?/0x01406d2?/
+   0x010069a?/0x01006da?/014069a?/0x01406da? */
+	OPTABLE(0x20, 0x78, 4, none),
+};
+
+static const struct optables_list {
+	const struct optable *ptr;
+	int size;
+} optables[] = {
+#define OPTABLES(no)                                                   \
+	{                                                              \
+		.ptr  = optable_##no,                                  \
+		.size = sizeof(optable_##no) / sizeof(struct optable), \
+	}
+	OPTABLES(0),
+	OPTABLES(1),
+	OPTABLES(2),
+	OPTABLES(3),
+	OPTABLES(4),
+
+};
+
+const unsigned char condmask[] = {
+	0x00, 0x40, 0x01, 0x04, 0x02, 0x08, 0x10, 0x20
+};
+
+static int isbranch(struct task_struct *task, int reson)
+{
+	unsigned char cond = h8300_get_reg(task, PT_CCR);
+
+	/* encode complex conditions */
+	/* B4: N^V
+	   B5: Z|(N^V)
+	   B6: C|Z */
+	__asm__("bld #3,%w0\n\t"
+		"bxor #1,%w0\n\t"
+		"bst #4,%w0\n\t"
+		"bor #2,%w0\n\t"
+		"bst #5,%w0\n\t"
+		"bld #2,%w0\n\t"
+		"bor #0,%w0\n\t"
+		"bst #6,%w0\n\t"
+		: "=&r"(cond) : "0"(cond) : "cc");
+	cond &= condmask[reson >> 1];
+	if (!(reson & 1))
+		return cond == 0;
+	else
+		return cond != 0;
+}
+
+static unsigned short *decode(struct task_struct *child,
+			      const struct optable *op,
+			      char *fetch_p, unsigned short *pc,
+			      unsigned char inst)
+{
+	unsigned long addr;
+	unsigned long *sp;
+	int regno;
+
+	switch (op->type) {
+	case none:
+		return (unsigned short *)pc + op->length;
+	case jabs:
+		addr = *(unsigned long *)pc;
+		return (unsigned short *)(addr & 0x00ffffff);
+	case ind:
+		addr = *pc & 0xff;
+		return (unsigned short *)(*(unsigned long *)addr);
+	case ret:
+		sp = (unsigned long *)h8300_get_reg(child, PT_USP);
+		/* user stack frames
+		   |   er0  | temporary saved
+		   +--------+
+		   |   exp  | exception stack frames
+		   +--------+
+		   | ret pc | userspace return address
+		*/
+		return (unsigned short *)(*(sp+2) & 0x00ffffff);
+	case reg:
+		regno = (*pc >> 4) & 0x07;
+		if (regno == 0)
+			addr = h8300_get_reg(child, PT_ER0);
+		else
+			addr = h8300_get_reg(child, regno-1 + PT_ER1);
+		return (unsigned short *)addr;
+	case relb:
+		if (inst == 0x55 || isbranch(child, inst & 0x0f))
+			pc = (unsigned short *)((unsigned long)pc +
+						((signed char)(*fetch_p)));
+		return pc+1; /* skip myself */
+	case relw:
+		if (inst == 0x5c || isbranch(child, (*fetch_p & 0xf0) >> 4))
+			pc = (unsigned short *)((unsigned long)pc +
+						((signed short)(*(pc+1))));
+		return pc+2; /* skip myself */
+	default:
+		return NULL;
+	}
+}
+
+static unsigned short *nextpc(struct task_struct *child, unsigned short *pc)
+{
+	const struct optable *op;
+	unsigned char *fetch_p;
+	int op_len;
+	unsigned char inst;
+
+	op = optables[0].ptr;
+	op_len = optables[0].size;
+	fetch_p = (unsigned char *)pc;
+	inst = *fetch_p++;
+	do {
+		if ((inst & op->bitmask) == op->bitpattern) {
+			if (op->length < 0) {
+				op = optables[-op->length].ptr;
+				op_len = optables[-op->length].size + 1;
+				inst = *fetch_p++;
+			} else
+				return decode(child, op, fetch_p, pc, inst);
+		} else
+			op++;
+	} while (--op_len > 0);
+	return NULL;
+}
+
+/* Set breakpoint(s) to simulate a single step from the current PC.  */
+
+void user_enable_single_step(struct task_struct *child)
+{
+	unsigned short *next;
+
+	next = nextpc(child, (unsigned short *)h8300_get_reg(child, PT_PC));
+	child->thread.breakinfo.addr = next;
+	child->thread.breakinfo.inst = *next;
+	*next = BREAKINST;
+}
+
+asmlinkage void trace_trap(unsigned long bp)
+{
+	if ((unsigned long)current->thread.breakinfo.addr == bp) {
+		user_disable_single_step(current);
+		force_sig(SIGTRAP, current);
+	} else
+		force_sig(SIGILL, current);
+}
diff --git a/arch/h8300/kernel/ptrace_s.c b/arch/h8300/kernel/ptrace_s.c
new file mode 100644
index 0000000..c0af930
--- /dev/null
+++ b/arch/h8300/kernel/ptrace_s.c
@@ -0,0 +1,44 @@
+/*
+ *  linux/arch/h8300/kernel/ptrace_h8s.c
+ *    ptrace cpu depend helper functions
+ *
+ *  Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of
+ * this archive for more details.
+ */
+
+#include <linux/linkage.h>
+#include <linux/sched/signal.h>
+#include <linux/errno.h>
+#include <asm/ptrace.h>
+
+#define CCR_MASK  0x6f
+#define EXR_TRACE 0x80
+
+/* disable singlestep */
+void user_disable_single_step(struct task_struct *child)
+{
+	unsigned char exr;
+
+	exr = h8300_get_reg(child, PT_EXR);
+	exr &= ~EXR_TRACE;
+	h8300_put_reg(child, PT_EXR, exr);
+}
+
+/* enable singlestep */
+void user_enable_single_step(struct task_struct *child)
+{
+	unsigned char exr;
+
+	exr = h8300_get_reg(child, PT_EXR);
+	exr |= EXR_TRACE;
+	h8300_put_reg(child, PT_EXR, exr);
+}
+
+asmlinkage void trace_trap(unsigned long bp)
+{
+	(void)bp;
+	force_sig(SIGTRAP, current);
+}
diff --git a/arch/h8300/kernel/setup.c b/arch/h8300/kernel/setup.c
new file mode 100644
index 0000000..34e2df5
--- /dev/null
+++ b/arch/h8300/kernel/setup.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/arch/h8300/kernel/setup.c
+ *
+ *  Copyright (C) 2001-2014 Yoshinori Sato <ysato@users.sourceforge.jp>
+ */
+
+/*
+ * This file handles the architecture-dependent parts of system setup
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/console.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/bootmem.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_address.h>
+#include <linux/clk-provider.h>
+#include <linux/memblock.h>
+#include <linux/screen_info.h>
+#include <linux/clocksource.h>
+
+#include <asm/setup.h>
+#include <asm/irq.h>
+#include <asm/pgtable.h>
+#include <asm/sections.h>
+#include <asm/page.h>
+
+#if defined(CONFIG_CPU_H8300H)
+#define CPU "H8/300H"
+#elif defined(CONFIG_CPU_H8S)
+#define CPU "H8S"
+#else
+#define CPU "Unknown"
+#endif
+
+unsigned long memory_start;
+unsigned long memory_end;
+EXPORT_SYMBOL(memory_end);
+static unsigned long freq;
+extern char __dtb_start[];
+
+#ifdef CONFIG_VT
+struct screen_info screen_info;
+#endif
+
+char __initdata command_line[COMMAND_LINE_SIZE];
+
+void sim_console_register(void);
+
+void __init h8300_fdt_init(void *fdt, char *bootargs)
+{
+	if (!fdt)
+		fdt = __dtb_start;
+	else
+		strcpy(command_line, bootargs);
+
+	early_init_dt_scan(fdt);
+	memblock_allow_resize();
+}
+
+static void __init bootmem_init(void)
+{
+	struct memblock_region *region;
+
+	memory_end = memory_start = 0;
+
+	/* Find main memory where is the kernel */
+	for_each_memblock(memory, region) {
+		memory_start = region->base;
+		memory_end = region->base + region->size;
+	}
+
+	if (!memory_end)
+		panic("No memory!");
+
+	/* setup bootmem globals (we use no_bootmem, but mm still depends on this) */
+	min_low_pfn = PFN_UP(memory_start);
+	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
+	max_pfn = max_low_pfn;
+
+	memblock_reserve(__pa(_stext), _end - _stext);
+
+	early_init_fdt_reserve_self();
+	early_init_fdt_scan_reserved_mem();
+
+	memblock_dump_all();
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+	unflatten_and_copy_device_tree();
+
+	init_mm.start_code = (unsigned long) _stext;
+	init_mm.end_code = (unsigned long) _etext;
+	init_mm.end_data = (unsigned long) _edata;
+	init_mm.brk = (unsigned long) 0;
+
+	pr_notice("\r\n\nuClinux " CPU "\n");
+	pr_notice("Flat model support (C) 1998,1999 Kenneth Albanowski, D. Jeff Dionne\n");
+
+	if (*command_line)
+		strcpy(boot_command_line, command_line);
+	*cmdline_p = boot_command_line;
+
+	parse_early_param();
+
+	bootmem_init();
+	/*
+	 * get kmalloc into gear
+	 */
+	paging_init();
+}
+
+/*
+ *	Get CPU information for use by the procfs.
+ */
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+	char *cpu;
+
+	cpu = CPU;
+
+	seq_printf(m,  "CPU:\t\t%s\n"
+		   "Clock:\t\t%lu.%1luMHz\n"
+		   "BogoMips:\t%lu.%02lu\n"
+		   "Calibration:\t%lu loops\n",
+		   cpu,
+		   freq/1000, freq%1000,
+		   (loops_per_jiffy*HZ)/500000,
+		   ((loops_per_jiffy*HZ)/5000)%100,
+		   (loops_per_jiffy*HZ));
+
+	return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+	return *pos < num_possible_cpus() ?
+		((void *) 0x12345678) : NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	++*pos;
+	return c_start(m, pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+	.start	= c_start,
+	.next	= c_next,
+	.stop	= c_stop,
+	.show	= show_cpuinfo,
+};
+
+#if defined(CONFIG_CPU_H8300H)
+#define get_wait(base, addr) ({		\
+	int baddr;			\
+	baddr = ((addr) / 0x200000 * 2);			     \
+	w *= (readw((base) + 2) & (3 << baddr)) + 1;		     \
+	})
+#endif
+#if defined(CONFIG_CPU_H8S)
+#define get_wait(base, addr) ({		\
+	int baddr;			\
+	baddr = ((addr) / 0x200000 * 16);			     \
+	w *= (readl((base) + 2) & (7 << baddr)) + 1;	\
+	})
+#endif
+
+static __init int access_timing(void)
+{
+	struct device_node *bsc;
+	void __iomem *base;
+	unsigned long addr = (unsigned long)&__delay;
+	int bit = 1 << (addr / 0x200000);
+	int w;
+
+	bsc = of_find_compatible_node(NULL, NULL, "renesas,h8300-bsc");
+	base = of_iomap(bsc, 0);
+	w = (readb(base + 0) & bit)?2:1;
+	if (readb(base + 1) & bit)
+		w *= get_wait(base, addr);
+	else
+		w *= 2;
+	return w * 3 / 2;
+}
+
+void __init calibrate_delay(void)
+{
+	struct device_node *cpu;
+	int freq;
+
+	cpu = of_find_compatible_node(NULL, NULL, "renesas,h8300");
+	of_property_read_s32(cpu, "clock-frequency", &freq);
+	loops_per_jiffy = freq / HZ / (access_timing() * 2);
+	pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
+		loops_per_jiffy / (500000 / HZ),
+		(loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
+}
+
+
+void __init time_init(void)
+{
+	of_clk_init(NULL);
+	timer_probe();
+}
diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c
new file mode 100644
index 0000000..1e8070d
--- /dev/null
+++ b/arch/h8300/kernel/signal.c
@@ -0,0 +1,290 @@
+/*
+ *  linux/arch/h8300/kernel/signal.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+/*
+ * uClinux H8/300 support by Yoshinori Sato <ysato@users.sourceforge.jp>
+ *                and David McCullough <davidm@snapgear.com>
+ *
+ * Based on
+ * Linux/m68k by Hamish Macdonald
+ */
+
+/*
+ * ++roman (07/09/96): implemented signal stacks (specially for tosemu on
+ * Atari :-) Current limitation: Only one sigstack can be active at one time.
+ * If a second signal with SA_ONSTACK set arrives while working on a sigstack,
+ * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
+ * signal handlers!
+ */
+
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/highuid.h>
+#include <linux/personality.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/tracehook.h>
+
+#include <asm/setup.h>
+#include <linux/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/traps.h>
+#include <asm/ucontext.h>
+
+/*
+ * Do a signal return; undo the signal stack.
+ *
+ * Keep the return code on the stack quadword aligned!
+ * That makes the cache flush below easier.
+ */
+
+struct rt_sigframe {
+	long dummy_er0;
+	long dummy_vector;
+#if defined(CONFIG_CPU_H8S)
+	short dummy_exr;
+#endif
+	long dummy_pc;
+	char *pretcode;
+	struct siginfo *pinfo;
+	void *puc;
+	unsigned char retcode[8];
+	struct siginfo info;
+	struct ucontext uc;
+	int sig;
+} __packed __aligned(2);
+
+static inline int
+restore_sigcontext(struct sigcontext *usc, int *pd0)
+{
+	struct pt_regs *regs = current_pt_regs();
+	int err = 0;
+	unsigned int ccr;
+	unsigned int usp;
+	unsigned int er0;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current->restart_block.fn = do_no_restart_syscall;
+
+	/* restore passed registers */
+#define COPY(r)  do { err |= get_user(regs->r, &usc->sc_##r); } while (0)
+	COPY(er1);
+	COPY(er2);
+	COPY(er3);
+	COPY(er5);
+	COPY(pc);
+	ccr = regs->ccr & 0x10;
+	COPY(ccr);
+#undef COPY
+	regs->ccr &= 0xef;
+	regs->ccr |= ccr;
+	regs->orig_er0 = -1;		/* disable syscall checks */
+	err |= __get_user(usp, &usc->sc_usp);
+	regs->sp = usp;
+
+	err |= __get_user(er0, &usc->sc_er0);
+	*pd0 = er0;
+	return err;
+}
+
+asmlinkage int sys_rt_sigreturn(void)
+{
+	unsigned long usp = rdusp();
+	struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4);
+	sigset_t set;
+	int er0;
+
+	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+		goto badframe;
+
+	set_current_blocked(&set);
+
+	if (restore_sigcontext(&frame->uc.uc_mcontext, &er0))
+		goto badframe;
+
+	if (restore_altstack(&frame->uc.uc_stack))
+		goto badframe;
+
+	return er0;
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+static int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+			     unsigned long mask)
+{
+	int err = 0;
+
+	err |= __put_user(regs->er0, &sc->sc_er0);
+	err |= __put_user(regs->er1, &sc->sc_er1);
+	err |= __put_user(regs->er2, &sc->sc_er2);
+	err |= __put_user(regs->er3, &sc->sc_er3);
+	err |= __put_user(regs->er4, &sc->sc_er4);
+	err |= __put_user(regs->er5, &sc->sc_er5);
+	err |= __put_user(regs->er6, &sc->sc_er6);
+	err |= __put_user(rdusp(),   &sc->sc_usp);
+	err |= __put_user(regs->pc,  &sc->sc_pc);
+	err |= __put_user(regs->ccr, &sc->sc_ccr);
+	err |= __put_user(mask,      &sc->sc_mask);
+
+	return err;
+}
+
+static inline void __user *
+get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size)
+{
+	return (void __user *)((sigsp(rdusp(), ksig) - frame_size) & -8UL);
+}
+
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+			  struct pt_regs *regs)
+{
+	struct rt_sigframe *frame;
+	int err = 0;
+	unsigned char *ret;
+
+	frame = get_sigframe(ksig, regs, sizeof(*frame));
+
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		return -EFAULT;
+
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+		err |= copy_siginfo_to_user(&frame->info, &ksig->info);
+
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(0, &frame->uc.uc_link);
+	err |= __save_altstack(&frame->uc.uc_stack, rdusp());
+	err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
+	err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+	if (err)
+		return -EFAULT;
+
+	/* Set up to return from userspace.  */
+	ret = (unsigned char *)&frame->retcode;
+	if (ksig->ka.sa.sa_flags & SA_RESTORER)
+		ret = (unsigned char *)(ksig->ka.sa.sa_restorer);
+	else {
+		/* sub.l er0,er0; mov.b #__NR_rt_sigreturn,r0l; trapa #0 */
+		err |= __put_user(0x1a80f800 + (__NR_rt_sigreturn & 0xff),
+				  (unsigned long *)(frame->retcode + 0));
+		err |= __put_user(0x5700,
+				  (unsigned short *)(frame->retcode + 4));
+	}
+	err |= __put_user(ret, &frame->pretcode);
+
+	if (err)
+		return -EFAULT;
+
+	/* Set up registers for signal handler */
+	regs->sp  = (unsigned long)frame;
+	regs->pc  = (unsigned long)ksig->ka.sa.sa_handler;
+	regs->er0 = ksig->sig;
+	regs->er1 = (unsigned long)&(frame->info);
+	regs->er2 = (unsigned long)&frame->uc;
+	regs->er5 = current->mm->start_data;	/* GOT base */
+
+	return 0;
+}
+
+static void
+handle_restart(struct pt_regs *regs, struct k_sigaction *ka)
+{
+	switch (regs->er0) {
+	case -ERESTARTNOHAND:
+		if (!ka)
+			goto do_restart;
+		regs->er0 = -EINTR;
+		break;
+	case -ERESTART_RESTARTBLOCK:
+		if (!ka) {
+			regs->er0 = __NR_restart_syscall;
+			regs->pc -= 2;
+		} else
+			regs->er0 = -EINTR;
+		break;
+	case -ERESTARTSYS:
+		if (!(ka->sa.sa_flags & SA_RESTART)) {
+			regs->er0 = -EINTR;
+			break;
+		}
+		/* fallthrough */
+	case -ERESTARTNOINTR:
+do_restart:
+		regs->er0 = regs->orig_er0;
+		regs->pc -= 2;
+		break;
+	}
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+	sigset_t *oldset = sigmask_to_save();
+	int ret;
+	/* are we from a system call? */
+	if (regs->orig_er0 >= 0)
+		handle_restart(regs, &ksig->ka);
+
+	ret = setup_rt_frame(ksig, oldset, regs);
+
+	signal_setup_done(ret, ksig, 0);
+}
+
+/*
+ * Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ */
+static void do_signal(struct pt_regs *regs)
+{
+	struct ksignal ksig;
+
+	current->thread.esp0 = (unsigned long) regs;
+
+	if (get_signal(&ksig)) {
+		/* Whee!  Actually deliver the signal.  */
+		handle_signal(&ksig, regs);
+		return;
+	}
+	/* Did we come from a system call? */
+	if (regs->orig_er0 >= 0)
+		handle_restart(regs, NULL);
+
+	/* If there's no signal to deliver, we just restore the saved mask.  */
+	restore_saved_sigmask();
+}
+
+asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
+{
+	if (thread_info_flags & _TIF_SIGPENDING)
+		do_signal(regs);
+
+	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+		clear_thread_flag(TIF_NOTIFY_RESUME);
+		tracehook_notify_resume(regs);
+	}
+}
diff --git a/arch/h8300/kernel/sim-console.c b/arch/h8300/kernel/sim-console.c
new file mode 100644
index 0000000..03aa35b
--- /dev/null
+++ b/arch/h8300/kernel/sim-console.c
@@ -0,0 +1,31 @@
+/*
+ * arch/h8300/kernel/sim-console.c
+ *
+ *  Copyright (C) 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/serial_core.h>
+
+static void sim_write(struct console *con, const char *s, unsigned n)
+{
+	register const char *_ptr __asm__("er1") = s;
+	register const unsigned _len __asm__("er2") = n;
+
+	__asm__("sub.l er0,er0\n\t"		/* er0 = 1 (stdout) */
+		"inc.l #1,er0\n\t"
+		".byte 0x5e,0x00,0x00,0xc7\n\t" /* jsr @0xc7 (sys_write) */
+		: : "g"(_ptr), "g"(_len):"er0");
+}
+
+static int __init sim_setup(struct earlycon_device *device, const char *opt)
+{
+	device->con->write = sim_write;
+	return 0;
+}
+
+EARLYCON_DECLARE(h8sim, sim_setup);
diff --git a/arch/h8300/kernel/syscalls.c b/arch/h8300/kernel/syscalls.c
new file mode 100644
index 0000000..9022036
--- /dev/null
+++ b/arch/h8300/kernel/syscalls.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/syscalls.h>
+#include <linux/signal.h>
+#include <linux/unistd.h>
+
+#undef __SYSCALL
+#define __SYSCALL(nr, call) [nr] = (call),
+
+#define sys_mmap2 sys_mmap_pgoff
+
+asmlinkage int sys_rt_sigreturn(void);
+
+void *_sys_call_table[__NR_syscalls] = {
+#include <asm/unistd.h>
+};
diff --git a/arch/h8300/kernel/traps.c b/arch/h8300/kernel/traps.c
new file mode 100644
index 0000000..e47a9e0
--- /dev/null
+++ b/arch/h8300/kernel/traps.c
@@ -0,0 +1,159 @@
+/*
+ * linux/arch/h8300/boot/traps.c -- general exception handling code
+ * H8/300 support Yoshinori Sato <ysato@users.sourceforge.jp>
+ *
+ * Cloned from Linux/m68k.
+ *
+ * No original Copyright holder listed,
+ * Probable original (C) Roman Zippel (assigned DJD, 1999)
+ *
+ * Copyright 1999-2000 D. Jeff Dionne, <jeff@rt-control.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/mm_types.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/bug.h>
+
+#include <asm/irq.h>
+#include <asm/traps.h>
+#include <asm/page.h>
+
+static DEFINE_SPINLOCK(die_lock);
+
+/*
+ * this must be called very early as the kernel might
+ * use some instruction that are emulated on the 060
+ */
+
+void __init base_trap_init(void)
+{
+}
+
+void __init trap_init(void)
+{
+}
+
+asmlinkage void set_esp0(unsigned long ssp)
+{
+	current->thread.esp0 = ssp;
+}
+
+/*
+ *	Generic dumping code. Used for panic and debug.
+ */
+
+static void dump(struct pt_regs *fp)
+{
+	unsigned long	*sp;
+	unsigned char	*tp;
+	int		i;
+
+	pr_info("\nCURRENT PROCESS:\n\n");
+	pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
+	if (current->mm) {
+		pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
+			(int) current->mm->start_code,
+			(int) current->mm->end_code,
+			(int) current->mm->start_data,
+			(int) current->mm->end_data,
+			(int) current->mm->end_data,
+			(int) current->mm->brk);
+		pr_info("USER-STACK=%08x  KERNEL-STACK=%08lx\n\n",
+			(int) current->mm->start_stack,
+			(int) PAGE_SIZE+(unsigned long)current);
+	}
+
+	show_regs(fp);
+	pr_info("\nCODE:");
+	tp = ((unsigned char *) fp->pc) - 0x20;
+	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
+		if ((i % 0x10) == 0)
+			pr_info("\n%08x: ", (int) (tp + i));
+		pr_info("%08x ", (int) *sp++);
+	}
+	pr_info("\n");
+
+	pr_info("\nKERNEL STACK:");
+	tp = ((unsigned char *) fp) - 0x40;
+	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
+		if ((i % 0x10) == 0)
+			pr_info("\n%08x: ", (int) (tp + i));
+		pr_info("%08x ", (int) *sp++);
+	}
+	pr_info("\n");
+	if (STACK_MAGIC != *(unsigned long *)((unsigned long)current+PAGE_SIZE))
+		pr_info("(Possibly corrupted stack page??)\n");
+
+	pr_info("\n\n");
+}
+
+void die(const char *str, struct pt_regs *fp, unsigned long err)
+{
+	static int diecount;
+
+	oops_enter();
+
+	console_verbose();
+	spin_lock_irq(&die_lock);
+	report_bug(fp->pc, fp);
+	pr_crit("%s: %04lx [#%d] ", str, err & 0xffff, ++diecount);
+	dump(fp);
+
+	spin_unlock_irq(&die_lock);
+	do_exit(SIGSEGV);
+}
+
+static int kstack_depth_to_print = 24;
+
+void show_stack(struct task_struct *task, unsigned long *esp)
+{
+	unsigned long *stack,  addr;
+	int i;
+
+	if (esp == NULL)
+		esp = (unsigned long *) &esp;
+
+	stack = esp;
+
+	pr_info("Stack from %08lx:", (unsigned long)stack);
+	for (i = 0; i < kstack_depth_to_print; i++) {
+		if (((unsigned long)stack & (THREAD_SIZE - 1)) >=
+		    THREAD_SIZE-4)
+			break;
+		if (i % 8 == 0)
+			pr_info(" ");
+		pr_cont(" %08lx", *stack++);
+	}
+
+	pr_info("\nCall Trace:\n");
+	i = 0;
+	stack = esp;
+	while (((unsigned long)stack & (THREAD_SIZE - 1)) < THREAD_SIZE-4) {
+		addr = *stack++;
+		/*
+		 * If the address is either in the text segment of the
+		 * kernel, or in the region which contains vmalloc'ed
+		 * memory, it *may* be the address of a calling
+		 * routine; if so, print it so that someone tracing
+		 * down the cause of the crash will be able to figure
+		 * out the call path that was taken.
+		 */
+		if (check_kernel_text(addr)) {
+			if (i % 4 == 0)
+				pr_info("       ");
+			pr_cont(" [<%08lx>]", addr);
+			i++;
+		}
+	}
+	pr_info("\n");
+}
diff --git a/arch/h8300/kernel/vmlinux.lds.S b/arch/h8300/kernel/vmlinux.lds.S
new file mode 100644
index 0000000..35716a3
--- /dev/null
+++ b/arch/h8300/kernel/vmlinux.lds.S
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <asm-generic/vmlinux.lds.h>
+#include <asm/page.h>
+#include <asm/thread_info.h>
+
+#define ROMTOP 0x000000
+#define RAMTOP 0x400000
+
+jiffies = jiffies_64 + 4;
+
+ENTRY(_start)
+
+SECTIONS
+{
+#if defined(CONFIG_ROMKERNEL)
+	. = ROMTOP;
+	.vectors :
+	{
+	_vector = . ;
+		*(.vector*)
+	}
+#else
+	. = RAMTOP;
+	_ramstart = .;
+	. = . + CONFIG_OFFSET;
+#endif
+	_text = .;
+	HEAD_TEXT_SECTION
+	.text : {
+	_stext = . ;
+		TEXT_TEXT
+		SCHED_TEXT
+		CPUIDLE_TEXT
+		LOCK_TEXT
+#if defined(CONFIG_ROMKERNEL)
+		*(.int_redirect)
+#endif
+	_etext = . ;
+	}
+	EXCEPTION_TABLE(16)
+	NOTES
+	RO_DATA_SECTION(4)
+	ROMEND = .;
+#if defined(CONFIG_ROMKERNEL)
+	. = RAMTOP;
+	_ramstart = .;
+#define ADDR(x) ROMEND
+#endif
+	_sdata = . ;
+	__data_start = . ;
+	RW_DATA_SECTION(0, PAGE_SIZE, THREAD_SIZE)
+#if defined(CONFIG_ROMKERNEL)
+#undef ADDR
+#endif
+	. = ALIGN(0x4) ;
+	__init_begin = .;
+	INIT_TEXT_SECTION(4)
+	INIT_DATA_SECTION(4)
+	SECURITY_INIT
+	__init_end = .;
+	_edata = . ;
+	_begin_data = LOADADDR(.data);
+	_sbss =.;
+	BSS_SECTION(0, 0 ,0)
+	_ebss =.;
+	_ramend = .;
+	_end = .;
+	DISCARDS
+}