1/*
2 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2008-2009 PetaLogix
4 * Copyright (C) 2006 Atmark Techno, Inc.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#ifndef _ASM_MICROBLAZE_PROCESSOR_H
12#define _ASM_MICROBLAZE_PROCESSOR_H
13
14#include <asm/ptrace.h>
15#include <asm/setup.h>
16#include <asm/registers.h>
17#include <asm/entry.h>
18#include <asm/current.h>
19
20# ifndef __ASSEMBLY__
21/* from kernel/cpu/mb.c */
22extern const struct seq_operations cpuinfo_op;
23
24# define cpu_relax()		barrier()
25# define cpu_relax_lowlatency()	cpu_relax()
26
27#define task_pt_regs(tsk) \
28		(((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)
29
30/* Do necessary setup to start up a newly executed thread. */
31void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);
32
33extern void ret_from_fork(void);
34extern void ret_from_kernel_thread(void);
35
36# endif /* __ASSEMBLY__ */
37
38# ifndef CONFIG_MMU
39/*
40 * User space process size: memory size
41 *
42 * TASK_SIZE on MMU cpu is usually 1GB. However, on no-MMU arch, both
43 * user processes and the kernel is on the same memory region. They
44 * both share the memory space and that is limited by the amount of
45 * physical memory. thus, we set TASK_SIZE == amount of total memory.
46 */
47# define TASK_SIZE	(0x81000000 - 0x80000000)
48
49/*
50 * Default implementation of macro that returns current
51 * instruction pointer ("program counter").
52 */
53# define current_text_addr() ({ __label__ _l; _l: &&_l; })
54
55/*
56 * This decides where the kernel will search for a free chunk of vm
57 * space during mmap's. We won't be using it
58 */
59# define TASK_UNMAPPED_BASE	0
60
61/* definition in include/linux/sched.h */
62struct task_struct;
63
64/* thread_struct is gone. use thread_info instead. */
65struct thread_struct { };
66# define INIT_THREAD	{ }
67
68/* Free all resources held by a thread. */
69static inline void release_thread(struct task_struct *dead_task)
70{
71}
72
73/* Free all resources held by a thread. */
74static inline void exit_thread(void)
75{
76}
77
78extern unsigned long thread_saved_pc(struct task_struct *t);
79
80extern unsigned long get_wchan(struct task_struct *p);
81
82# define KSTK_EIP(tsk)	(0)
83# define KSTK_ESP(tsk)	(0)
84
85# else /* CONFIG_MMU */
86
87/*
88 * This is used to define STACK_TOP, and with MMU it must be below
89 * kernel base to select the correct PGD when handling MMU exceptions.
90 */
91# define TASK_SIZE	(CONFIG_KERNEL_START)
92
93/*
94 * This decides where the kernel will search for a free chunk of vm
95 * space during mmap's.
96 */
97# define TASK_UNMAPPED_BASE	(TASK_SIZE / 8 * 3)
98
99# define THREAD_KSP	0
100
101#  ifndef __ASSEMBLY__
102
103/*
104 * Default implementation of macro that returns current
105 * instruction pointer ("program counter").
106 */
107#  define current_text_addr()	({ __label__ _l; _l: &&_l; })
108
109/* If you change this, you must change the associated assembly-languages
110 * constants defined below, THREAD_*.
111 */
112struct thread_struct {
113	/* kernel stack pointer (must be first field in structure) */
114	unsigned long	ksp;
115	unsigned long	ksp_limit;	/* if ksp <= ksp_limit stack overflow */
116	void		*pgdir;		/* root of page-table tree */
117	struct pt_regs	*regs;		/* Pointer to saved register state */
118};
119
120#  define INIT_THREAD { \
121	.ksp   = sizeof init_stack + (unsigned long)init_stack, \
122	.pgdir = swapper_pg_dir, \
123}
124
125/* Free all resources held by a thread. */
126static inline void release_thread(struct task_struct *dead_task)
127{
128}
129
130/* Free current thread data structures etc.  */
131static inline void exit_thread(void)
132{
133}
134
135/* Return saved (kernel) PC of a blocked thread.  */
136#  define thread_saved_pc(tsk)	\
137	((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0)
138
139unsigned long get_wchan(struct task_struct *p);
140
141/* The size allocated for kernel stacks. This _must_ be a power of two! */
142# define KERNEL_STACK_SIZE	0x2000
143
144/* Return some info about the user process TASK.  */
145#  define task_tos(task)	((unsigned long)(task) + KERNEL_STACK_SIZE)
146#  define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
147
148#  define task_pt_regs_plus_args(tsk) \
149	((void *)task_pt_regs(tsk))
150
151#  define task_sp(task)	(task_regs(task)->r1)
152#  define task_pc(task)	(task_regs(task)->pc)
153/* Grotty old names for some.  */
154#  define KSTK_EIP(task)	(task_pc(task))
155#  define KSTK_ESP(task)	(task_sp(task))
156
157/* FIXME */
158#  define deactivate_mm(tsk, mm)	do { } while (0)
159
160#  define STACK_TOP	TASK_SIZE
161#  define STACK_TOP_MAX	STACK_TOP
162
163#ifdef CONFIG_DEBUG_FS
164extern struct dentry *of_debugfs_root;
165#endif
166
167#  endif /* __ASSEMBLY__ */
168# endif /* CONFIG_MMU */
169#endif /* _ASM_MICROBLAZE_PROCESSOR_H */
170