aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sh/include/asm/processor_64.h
blob: 740e268765963b9c91dcce4d4b204be0aeeceea2 (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
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
#ifndef __ASM_SH_PROCESSOR_64_H
#define __ASM_SH_PROCESSOR_64_H

/*
 * include/asm-sh/processor_64.h
 *
 * Copyright (C) 2000, 2001  Paolo Alberelli
 * Copyright (C) 2003  Paul Mundt
 * Copyright (C) 2004  Richard Curnow
 *
 * 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.
 */
#ifndef __ASSEMBLY__

#include <linux/compiler.h>
#include <asm/page.h>
#include <asm/types.h>
#include <cpu/registers.h>

/*
 * Default implementation of macro that returns current
 * instruction pointer ("program counter").
 */
#define current_text_addr() ({ \
void *pc; \
unsigned long long __dummy = 0; \
__asm__("gettr	tr0, %1\n\t" \
	"pta	4, tr0\n\t" \
	"gettr	tr0, %0\n\t" \
	"ptabs	%1, tr0\n\t"	\
	:"=r" (pc), "=r" (__dummy) \
	: "1" (__dummy)); \
pc; })

#endif

/*
 * User space process size: 2GB - 4k.
 */
#define TASK_SIZE	0x7ffff000UL

#define STACK_TOP	TASK_SIZE
#define STACK_TOP_MAX	STACK_TOP

/* This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#define TASK_UNMAPPED_BASE	(TASK_SIZE / 3)

/*
 * Bit of SR register
 *
 * FD-bit:
 *     When it's set, it means the processor doesn't have right to use FPU,
 *     and it results exception when the floating operation is executed.
 *
 * IMASK-bit:
 *     Interrupt level mask
 *
 * STEP-bit:
 *     Single step bit
 *
 */
#if defined(CONFIG_SH64_SR_WATCH)
#define SR_MMU   0x84000000
#else
#define SR_MMU   0x80000000
#endif

#define SR_IMASK 0x000000f0
#define SR_FD    0x00008000
#define SR_SSTEP 0x08000000

#ifndef __ASSEMBLY__

/*
 * FPU structure and data : require 8-byte alignment as we need to access it
   with fld.p, fst.p
 */

struct sh_fpu_hard_struct {
	unsigned long fp_regs[64];
	unsigned int fpscr;
	/* long status; * software status information */
};

/* Dummy fpu emulator  */
struct sh_fpu_soft_struct {
	unsigned long fp_regs[64];
	unsigned int fpscr;
	unsigned char lookahead;
	unsigned long entry_pc;
};

union thread_xstate {
	struct sh_fpu_hard_struct hardfpu;
	struct sh_fpu_soft_struct softfpu;
	/*
	 * The structure definitions only produce 32 bit alignment, yet we need
	 * to access them using 64 bit load/store as well.
	 */
	unsigned long long alignment_dummy;
};

struct thread_struct {
	unsigned long sp;
	unsigned long pc;

	/* Various thread flags, see SH_THREAD_xxx */
	unsigned long flags;

	/* This stores the address of the pt_regs built during a context
	   switch, or of the register save area built for a kernel mode
	   exception.  It is used for backtracing the stack of a sleeping task
	   or one that traps in kernel mode. */
        struct pt_regs *kregs;
	/* This stores the address of the pt_regs constructed on entry from
	   user mode.  It is a fixed value over the lifetime of a process, or
	   NULL for a kernel thread. */
	struct pt_regs *uregs;

	unsigned long address;
	/* Hardware debugging registers may come here */

	/* floating point info */
	union thread_xstate *xstate;
};

#define INIT_MMAP \
{ &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL }

#define INIT_THREAD  {				\
	.sp		= sizeof(init_stack) +	\
			  (long) &init_stack,	\
	.pc		= 0,			\
        .kregs		= &fake_swapper_regs,	\
	.uregs	        = NULL,			\
	.address	= 0,			\
	.flags		= 0,			\
}

/*
 * Do necessary setup to start up a newly executed thread.
 */
#define SR_USER (SR_MMU | SR_FD)

#define start_thread(_regs, new_pc, new_sp)			\
	_regs->sr = SR_USER;	/* User mode. */		\
	_regs->pc = new_pc - 4;	/* Compensate syscall exit */	\
	_regs->pc |= 1;		/* Set SHmedia ! */		\
	_regs->regs[18] = 0;					\
	_regs->regs[15] = new_sp

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

/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
/*
 * create a kernel thread without removing it from tasklists
 */
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);


/* Copy and release all segment info associated with a VM */
#define copy_segments(p, mm)	do { } while (0)
#define release_segments(mm)	do { } while (0)
#define forget_segments()	do { } while (0)
#define prepare_to_copy(tsk)	do { } while (0)
/*
 * FPU lazy state save handling.
 */

static inline void disable_fpu(void)
{
	unsigned long long __dummy;

	/* Set FD flag in SR */
	__asm__ __volatile__("getcon	" __SR ", %0\n\t"
			     "or	%0, %1, %0\n\t"
			     "putcon	%0, " __SR "\n\t"
			     : "=&r" (__dummy)
			     : "r" (SR_FD));
}

static inline void enable_fpu(void)
{
	unsigned long long __dummy;

	/* Clear out FD flag in SR */
	__asm__ __volatile__("getcon	" __SR ", %0\n\t"
			     "and	%0, %1, %0\n\t"
			     "putcon	%0, " __SR "\n\t"
			     : "=&r" (__dummy)
			     : "r" (~SR_FD));
}

/* Round to nearest, no exceptions on inexact, overflow, underflow,
   zero-divide, invalid.  Configure option for whether to flush denorms to
   zero, or except if a denorm is encountered.  */
#if defined(CONFIG_SH64_FPU_DENORM_FLUSH)
#define FPSCR_INIT  0x00040000
#else
#define FPSCR_INIT  0x00000000
#endif

#ifdef CONFIG_SH_FPU
/* Initialise the FP state of a task */
void fpinit(struct sh_fpu_hard_struct *fpregs);
#else
#define fpinit(fpregs)	do { } while (0)
#endif

extern struct task_struct *last_task_used_math;

/*
 * Return saved PC of a blocked thread.
 */
#define thread_saved_pc(tsk)	(tsk->thread.pc)

extern unsigned long get_wchan(struct task_struct *p);

#define KSTK_EIP(tsk)  ((tsk)->thread.pc)
#define KSTK_ESP(tsk)  ((tsk)->thread.sp)

#endif	/* __ASSEMBLY__ */
#endif /* __ASM_SH_PROCESSOR_64_H */