1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
4 * Copyright (C) 2008-2009 PetaLogix
5 * Copyright (C) 2006 Atmark Techno, Inc.
6 */
7
8 #ifndef _ASM_MICROBLAZE_PROCESSOR_H
9 #define _ASM_MICROBLAZE_PROCESSOR_H
10
11 #include <asm/ptrace.h>
12 #include <asm/setup.h>
13 #include <asm/registers.h>
14 #include <asm/entry.h>
15 #include <asm/current.h>
16
17 # ifndef __ASSEMBLY__
18 /* from kernel/cpu/mb.c */
19 extern const struct seq_operations cpuinfo_op;
20
21 # define cpu_relax() barrier()
22
23 #define task_pt_regs(tsk) \
24 (((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)
25
26 /* Do necessary setup to start up a newly executed thread. */
27 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);
28
29 extern void ret_from_fork(void);
30 extern void ret_from_kernel_thread(void);
31
32 # endif /* __ASSEMBLY__ */
33
34 # ifndef CONFIG_MMU
35 /*
36 * User space process size: memory size
37 *
38 * TASK_SIZE on MMU cpu is usually 1GB. However, on no-MMU arch, both
39 * user processes and the kernel is on the same memory region. They
40 * both share the memory space and that is limited by the amount of
41 * physical memory. thus, we set TASK_SIZE == amount of total memory.
42 */
43 # define TASK_SIZE (0x81000000 - 0x80000000)
44
45 /*
46 * This decides where the kernel will search for a free chunk of vm
47 * space during mmap's. We won't be using it
48 */
49 # define TASK_UNMAPPED_BASE 0
50
51 /* definition in include/linux/sched.h */
52 struct task_struct;
53
54 /* thread_struct is gone. use thread_info instead. */
55 struct thread_struct { };
56 # define INIT_THREAD { }
57
58 /* Free all resources held by a thread. */
release_thread(struct task_struct * dead_task)59 static inline void release_thread(struct task_struct *dead_task)
60 {
61 }
62
63 extern unsigned long get_wchan(struct task_struct *p);
64
65 # define KSTK_EIP(tsk) (0)
66 # define KSTK_ESP(tsk) (0)
67
68 # else /* CONFIG_MMU */
69
70 /*
71 * This is used to define STACK_TOP, and with MMU it must be below
72 * kernel base to select the correct PGD when handling MMU exceptions.
73 */
74 # define TASK_SIZE (CONFIG_KERNEL_START)
75
76 /*
77 * This decides where the kernel will search for a free chunk of vm
78 * space during mmap's.
79 */
80 # define TASK_UNMAPPED_BASE (TASK_SIZE / 8 * 3)
81
82 # define THREAD_KSP 0
83
84 # ifndef __ASSEMBLY__
85
86 /* If you change this, you must change the associated assembly-languages
87 * constants defined below, THREAD_*.
88 */
89 struct thread_struct {
90 /* kernel stack pointer (must be first field in structure) */
91 unsigned long ksp;
92 unsigned long ksp_limit; /* if ksp <= ksp_limit stack overflow */
93 void *pgdir; /* root of page-table tree */
94 struct pt_regs *regs; /* Pointer to saved register state */
95 };
96
97 # define INIT_THREAD { \
98 .ksp = sizeof init_stack + (unsigned long)init_stack, \
99 .pgdir = swapper_pg_dir, \
100 }
101
102 /* Free all resources held by a thread. */
release_thread(struct task_struct * dead_task)103 static inline void release_thread(struct task_struct *dead_task)
104 {
105 }
106
107 unsigned long get_wchan(struct task_struct *p);
108
109 /* The size allocated for kernel stacks. This _must_ be a power of two! */
110 # define KERNEL_STACK_SIZE 0x2000
111
112 /* Return some info about the user process TASK. */
113 # define task_tos(task) ((unsigned long)(task) + KERNEL_STACK_SIZE)
114 # define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
115
116 # define task_pt_regs_plus_args(tsk) \
117 ((void *)task_pt_regs(tsk))
118
119 # define task_sp(task) (task_regs(task)->r1)
120 # define task_pc(task) (task_regs(task)->pc)
121 /* Grotty old names for some. */
122 # define KSTK_EIP(task) (task_pc(task))
123 # define KSTK_ESP(task) (task_sp(task))
124
125 /* FIXME */
126 # define deactivate_mm(tsk, mm) do { } while (0)
127
128 # define STACK_TOP TASK_SIZE
129 # define STACK_TOP_MAX STACK_TOP
130
131 #ifdef CONFIG_DEBUG_FS
132 extern struct dentry *of_debugfs_root;
133 #endif
134
135 # endif /* __ASSEMBLY__ */
136 # endif /* CONFIG_MMU */
137 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */
138