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_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. */
31 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);
32
33 extern void ret_from_fork(void);
34 extern 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 */
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. */
release_thread(struct task_struct * dead_task)69 static inline void release_thread(struct task_struct *dead_task)
70 {
71 }
72
73 extern unsigned long thread_saved_pc(struct task_struct *t);
74
75 extern unsigned long get_wchan(struct task_struct *p);
76
77 # define KSTK_EIP(tsk) (0)
78 # define KSTK_ESP(tsk) (0)
79
80 # else /* CONFIG_MMU */
81
82 /*
83 * This is used to define STACK_TOP, and with MMU it must be below
84 * kernel base to select the correct PGD when handling MMU exceptions.
85 */
86 # define TASK_SIZE (CONFIG_KERNEL_START)
87
88 /*
89 * This decides where the kernel will search for a free chunk of vm
90 * space during mmap's.
91 */
92 # define TASK_UNMAPPED_BASE (TASK_SIZE / 8 * 3)
93
94 # define THREAD_KSP 0
95
96 # ifndef __ASSEMBLY__
97
98 /*
99 * Default implementation of macro that returns current
100 * instruction pointer ("program counter").
101 */
102 # define current_text_addr() ({ __label__ _l; _l: &&_l; })
103
104 /* If you change this, you must change the associated assembly-languages
105 * constants defined below, THREAD_*.
106 */
107 struct thread_struct {
108 /* kernel stack pointer (must be first field in structure) */
109 unsigned long ksp;
110 unsigned long ksp_limit; /* if ksp <= ksp_limit stack overflow */
111 void *pgdir; /* root of page-table tree */
112 struct pt_regs *regs; /* Pointer to saved register state */
113 };
114
115 # define INIT_THREAD { \
116 .ksp = sizeof init_stack + (unsigned long)init_stack, \
117 .pgdir = swapper_pg_dir, \
118 }
119
120 /* Free all resources held by a thread. */
release_thread(struct task_struct * dead_task)121 static inline void release_thread(struct task_struct *dead_task)
122 {
123 }
124
125 /* Return saved (kernel) PC of a blocked thread. */
126 # define thread_saved_pc(tsk) \
127 ((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0)
128
129 unsigned long get_wchan(struct task_struct *p);
130
131 /* The size allocated for kernel stacks. This _must_ be a power of two! */
132 # define KERNEL_STACK_SIZE 0x2000
133
134 /* Return some info about the user process TASK. */
135 # define task_tos(task) ((unsigned long)(task) + KERNEL_STACK_SIZE)
136 # define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
137
138 # define task_pt_regs_plus_args(tsk) \
139 ((void *)task_pt_regs(tsk))
140
141 # define task_sp(task) (task_regs(task)->r1)
142 # define task_pc(task) (task_regs(task)->pc)
143 /* Grotty old names for some. */
144 # define KSTK_EIP(task) (task_pc(task))
145 # define KSTK_ESP(task) (task_sp(task))
146
147 /* FIXME */
148 # define deactivate_mm(tsk, mm) do { } while (0)
149
150 # define STACK_TOP TASK_SIZE
151 # define STACK_TOP_MAX STACK_TOP
152
153 #ifdef CONFIG_DEBUG_FS
154 extern struct dentry *of_debugfs_root;
155 #endif
156
157 # endif /* __ASSEMBLY__ */
158 # endif /* CONFIG_MMU */
159 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */
160