summaryrefslogtreecommitdiff
path: root/arch/m68k/include/asm/processor.h
blob: d86b4009880b4e790c4abeb4cda8fbc38be7e238 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * include/asm-m68k/processor.h
 *
 * Copyright (C) 1995 Hamish Macdonald
 */

#ifndef __ASM_M68K_PROCESSOR_H
#define __ASM_M68K_PROCESSOR_H

#include <linux/thread_info.h>
#include <asm/fpu.h>
#include <asm/ptrace.h>

static inline unsigned long rdusp(void)
{
#ifdef CONFIG_COLDFIRE_SW_A7
	extern unsigned int sw_usp;
	return sw_usp;
#else
	register unsigned long usp __asm__("a0");
	/* move %usp,%a0 */
	__asm__ __volatile__(".word 0x4e68" : "=a" (usp));
	return usp;
#endif
}

static inline void wrusp(unsigned long usp)
{
#ifdef CONFIG_COLDFIRE_SW_A7
	extern unsigned int sw_usp;
	sw_usp = usp;
#else
	register unsigned long a0 __asm__("a0") = usp;
	/* move %a0,%usp */
	__asm__ __volatile__(".word 0x4e60" : : "a" (a0) );
#endif
}

/*
 * User space process size: 3.75GB. This is hardcoded into a few places,
 * so don't change it unless you know what you are doing.
 */
#ifdef CONFIG_MMU
#if defined(CONFIG_COLDFIRE)
#define TASK_SIZE	(0xC0000000UL)
#elif defined(CONFIG_SUN3)
#define TASK_SIZE	(0x0E000000UL)
#else
#define TASK_SIZE	(0xF0000000UL)
#endif
#else
#define TASK_SIZE	(0xFFFFFFFFUL)
#endif

#ifdef __KERNEL__
#define STACK_TOP	TASK_SIZE
#define STACK_TOP_MAX	STACK_TOP
#endif

/* This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#ifdef CONFIG_MMU
#if defined(CONFIG_COLDFIRE)
#define TASK_UNMAPPED_BASE	0x60000000UL
#elif defined(CONFIG_SUN3)
#define TASK_UNMAPPED_BASE	0x0A000000UL
#else
#define TASK_UNMAPPED_BASE	0xC0000000UL
#endif
#define TASK_UNMAPPED_ALIGN(addr, off)	PAGE_ALIGN(addr)
#else
#define TASK_UNMAPPED_BASE	0
#endif

/* Address spaces (or Function Codes in Motorola lingo) */
#define USER_DATA     1
#define USER_PROGRAM  2
#define SUPER_DATA    5
#define SUPER_PROGRAM 6
#define CPU_SPACE     7

#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES
/*
 * Set the SFC/DFC registers for special MM operations.  For most normal
 * operation these remain set to USER_DATA for the uaccess routines.
 */
static inline void set_fc(unsigned long val)
{
	WARN_ON_ONCE(in_interrupt());

	__asm__ __volatile__ ("movec %0,%/sfc\n\t"
			      "movec %0,%/dfc\n\t"
			      : /* no outputs */ : "r" (val) : "memory");
}
#else
static inline void set_fc(unsigned long val)
{
}
#endif /* CONFIG_CPU_HAS_ADDRESS_SPACES */

struct thread_struct {
	unsigned long  ksp;		/* kernel stack pointer */
	unsigned long  usp;		/* user stack pointer */
	unsigned short sr;		/* saved status register */
	unsigned short fc;		/* saved fc (sfc, dfc) */
	unsigned long  crp[2];		/* cpu root pointer */
	unsigned long  esp0;		/* points to SR of stack frame */
	unsigned long  faddr;		/* info about last fault */
	int            signo, code;
	unsigned long  fp[8*3];
	unsigned long  fpcntl[3];	/* fp control regs */
	unsigned char  fpstate[FPSTATESIZE];  /* floating point state */
};

#define INIT_THREAD  {							\
	.ksp	= sizeof(init_stack) + (unsigned long) init_stack,	\
	.sr	= PS_S,							\
	.fc	= USER_DATA,						\
}

/*
 * ColdFire stack format sbould be 0x4 for an aligned usp (will always be
 * true on thread creation). We need to set this explicitly.
 */
#ifdef CONFIG_COLDFIRE
#define setframeformat(_regs)	do { (_regs)->format = 0x4; } while(0)
#else
#define setframeformat(_regs)	do { } while (0)
#endif

/*
 * Do necessary setup to start up a newly executed thread.
 */
static inline void start_thread(struct pt_regs * regs, unsigned long pc,
				unsigned long usp)
{
	regs->pc = pc;
	regs->sr &= ~0x2000;
	setframeformat(regs);
	wrusp(usp);
}

/* Forward declaration, a strange C thing */
struct task_struct;

/* Free all resources held by a thread. */
static inline void release_thread(struct task_struct *dead_task)
{
}

unsigned long __get_wchan(struct task_struct *p);
void show_registers(struct pt_regs *regs);

#define	KSTK_EIP(tsk)	\
    ({			\
	unsigned long eip = 0;	 \
	if ((tsk)->thread.esp0 > PAGE_SIZE && \
	    (virt_addr_valid((tsk)->thread.esp0))) \
	      eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
	eip; })
#define	KSTK_ESP(tsk)	((tsk) == current ? rdusp() : (tsk)->thread.usp)

#define task_pt_regs(tsk)	((struct pt_regs *) ((tsk)->thread.esp0))

#define cpu_relax()	barrier()

#endif