1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * include/asm-h8300/processor.h
4 *
5 * Copyright (C) 2002 Yoshinori Sato
6 *
7 * Based on: linux/asm-m68nommu/processor.h
8 *
9 * Copyright (C) 1995 Hamish Macdonald
10 */
11
12#ifndef __ASM_H8300_PROCESSOR_H
13#define __ASM_H8300_PROCESSOR_H
14
15#include <linux/compiler.h>
16#include <asm/segment.h>
17#include <asm/ptrace.h>
18#include <asm/current.h>
19
20static inline unsigned long rdusp(void)
21{
22	extern unsigned int	_sw_usp;
23
24	return _sw_usp;
25}
26
27static inline void wrusp(unsigned long usp)
28{
29	extern unsigned int	_sw_usp;
30
31	_sw_usp = usp;
32}
33
34/*
35 * User space process size: 3.75GB. This is hardcoded into a few places,
36 * so don't change it unless you know what you are doing.
37 */
38#define TASK_SIZE	(0xFFFFFFFFUL)
39
40#ifdef __KERNEL__
41#define STACK_TOP	TASK_SIZE
42#define STACK_TOP_MAX	STACK_TOP
43#endif
44
45/*
46 * This decides where the kernel will search for a free chunk of vm
47 * space during mmap's. We won't be using it
48 */
49#define TASK_UNMAPPED_BASE	0
50
51struct thread_struct {
52	unsigned long  ksp;		/* kernel stack pointer */
53	unsigned long  usp;		/* user stack pointer */
54	unsigned long  ccr;		/* saved status register */
55	unsigned long  esp0;            /* points to SR of stack frame */
56	struct {
57		unsigned short *addr;
58		unsigned short inst;
59	} breakinfo;
60};
61
62#define INIT_THREAD  {						\
63	.ksp  = sizeof(init_stack) + (unsigned long)init_stack, \
64	.usp  = 0,						\
65	.ccr  = PS_S,						\
66	.esp0 = 0,						\
67	.breakinfo = {						\
68		.addr = (unsigned short *)-1,			\
69		.inst = 0					\
70	}							\
71}
72
73/*
74 * Do necessary setup to start up a newly executed thread.
75 *
76 * pass the data segment into user programs if it exists,
77 * it can't hurt anything as far as I can tell
78 */
79#if defined(CONFIG_CPU_H8300H)
80#define start_thread(_regs, _pc, _usp)				\
81do {								\
82	(_regs)->pc = (_pc);					\
83	(_regs)->ccr = 0x00;	   /* clear all flags */	\
84	(_regs)->er5 = current->mm->start_data;	/* GOT base */	\
85	(_regs)->sp = ((unsigned long)(_usp)) - sizeof(unsigned long) * 3; \
86} while (0)
87#endif
88#if defined(CONFIG_CPU_H8S)
89#define start_thread(_regs, _pc, _usp)				\
90do {								\
91	(_regs)->pc = (_pc);					\
92	(_regs)->ccr = 0x00;	   /* clear kernel flag */	\
93	(_regs)->exr = 0x78;	   /* enable all interrupts */	\
94	(_regs)->er5 = current->mm->start_data;	/* GOT base */	\
95	/* 14 = space for retaddr(4), vector(4), er0(4) and exr(2) on stack */ \
96	(_regs)->sp = ((unsigned long)(_usp)) - 14;		\
97} while (0)
98#endif
99
100/* Forward declaration, a strange C thing */
101struct task_struct;
102
103/* Free all resources held by a thread. */
104static inline void release_thread(struct task_struct *dead_task)
105{
106}
107
108unsigned long get_wchan(struct task_struct *p);
109
110#define	KSTK_EIP(tsk)	\
111	({			 \
112		unsigned long eip = 0;	      \
113		if ((tsk)->thread.esp0 > PAGE_SIZE &&	\
114		    MAP_NR((tsk)->thread.esp0) < max_mapnr)	 \
115			eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
116		eip; })
117
118#define	KSTK_ESP(tsk)	((tsk) == current ? rdusp() : (tsk)->thread.usp)
119
120#define cpu_relax()    barrier()
121
122#define HARD_RESET_NOW() ({		\
123	local_irq_disable();		\
124	asm("jmp @@0");			\
125})
126
127#endif
128