xref: /linux/arch/microblaze/include/asm/processor.h (revision 163ec0369be4c26e68385f6cec88d0ee38c8d8e5)
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 */
22 extern const struct seq_operations cpuinfo_op;
23 
24 # define cpu_relax()		barrier()
25 # define cpu_sleep()		do {} while (0)
26 # define prepare_to_copy(tsk)	do {} while (0)
27 
28 #define task_pt_regs(tsk) \
29 		(((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)
30 
31 /* Do necessary setup to start up a newly executed thread. */
32 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);
33 
34 extern void ret_from_fork(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 */
62 struct task_struct;
63 
64 /* thread_struct is gone. use thread_info instead. */
65 struct thread_struct { };
66 # define INIT_THREAD	{ }
67 
68 /* Free all resources held by a thread. */
69 static inline void release_thread(struct task_struct *dead_task)
70 {
71 }
72 
73 /* Free all resources held by a thread. */
74 static inline void exit_thread(void)
75 {
76 }
77 
78 extern unsigned long thread_saved_pc(struct task_struct *t);
79 
80 extern unsigned long get_wchan(struct task_struct *p);
81 
82 /*
83  * create a kernel thread without removing it from tasklists
84  */
85 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
86 
87 # define KSTK_EIP(tsk)	(0)
88 # define KSTK_ESP(tsk)	(0)
89 
90 # else /* CONFIG_MMU */
91 
92 /*
93  * This is used to define STACK_TOP, and with MMU it must be below
94  * kernel base to select the correct PGD when handling MMU exceptions.
95  */
96 # define TASK_SIZE	(CONFIG_KERNEL_START)
97 
98 /*
99  * This decides where the kernel will search for a free chunk of vm
100  * space during mmap's.
101  */
102 # define TASK_UNMAPPED_BASE	(TASK_SIZE / 8 * 3)
103 
104 # define THREAD_KSP	0
105 
106 #  ifndef __ASSEMBLY__
107 
108 /*
109  * Default implementation of macro that returns current
110  * instruction pointer ("program counter").
111  */
112 #  define current_text_addr()	({ __label__ _l; _l: &&_l; })
113 
114 /* If you change this, you must change the associated assembly-languages
115  * constants defined below, THREAD_*.
116  */
117 struct thread_struct {
118 	/* kernel stack pointer (must be first field in structure) */
119 	unsigned long	ksp;
120 	unsigned long	ksp_limit;	/* if ksp <= ksp_limit stack overflow */
121 	void		*pgdir;		/* root of page-table tree */
122 	struct pt_regs	*regs;		/* Pointer to saved register state */
123 };
124 
125 #  define INIT_THREAD { \
126 	.ksp   = sizeof init_stack + (unsigned long)init_stack, \
127 	.pgdir = swapper_pg_dir, \
128 }
129 
130 /* Free all resources held by a thread. */
131 extern inline void release_thread(struct task_struct *dead_task)
132 {
133 }
134 
135 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
136 
137 /* Free current thread data structures etc.  */
138 static inline void exit_thread(void)
139 {
140 }
141 
142 /* Return saved (kernel) PC of a blocked thread.  */
143 #  define thread_saved_pc(tsk)	\
144 	((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0)
145 
146 unsigned long get_wchan(struct task_struct *p);
147 
148 /* The size allocated for kernel stacks. This _must_ be a power of two! */
149 # define KERNEL_STACK_SIZE	0x2000
150 
151 /* Return some info about the user process TASK.  */
152 #  define task_tos(task)	((unsigned long)(task) + KERNEL_STACK_SIZE)
153 #  define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
154 
155 #  define task_pt_regs_plus_args(tsk) \
156 	((void *)task_pt_regs(tsk))
157 
158 #  define task_sp(task)	(task_regs(task)->r1)
159 #  define task_pc(task)	(task_regs(task)->pc)
160 /* Grotty old names for some.  */
161 #  define KSTK_EIP(task)	(task_pc(task))
162 #  define KSTK_ESP(task)	(task_sp(task))
163 
164 /* FIXME */
165 #  define deactivate_mm(tsk, mm)	do { } while (0)
166 
167 #  define STACK_TOP	TASK_SIZE
168 #  define STACK_TOP_MAX	STACK_TOP
169 
170 void disable_hlt(void);
171 void enable_hlt(void);
172 void default_idle(void);
173 
174 #ifdef CONFIG_DEBUG_FS
175 extern struct dentry *of_debugfs_root;
176 #endif
177 
178 #  endif /* __ASSEMBLY__ */
179 # endif /* CONFIG_MMU */
180 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */
181