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 /*
35  * This is used to define STACK_TOP, and with MMU it must be below
36  * kernel base to select the correct PGD when handling MMU exceptions.
37  */
38 # define TASK_SIZE	(CONFIG_KERNEL_START)
39 
40 /*
41  * This decides where the kernel will search for a free chunk of vm
42  * space during mmap's.
43  */
44 # define TASK_UNMAPPED_BASE	(TASK_SIZE / 8 * 3)
45 
46 # define THREAD_KSP	0
47 
48 #  ifndef __ASSEMBLY__
49 
50 /* If you change this, you must change the associated assembly-languages
51  * constants defined below, THREAD_*.
52  */
53 struct thread_struct {
54 	/* kernel stack pointer (must be first field in structure) */
55 	unsigned long	ksp;
56 	unsigned long	ksp_limit;	/* if ksp <= ksp_limit stack overflow */
57 	void		*pgdir;		/* root of page-table tree */
58 	struct pt_regs	*regs;		/* Pointer to saved register state */
59 };
60 
61 #  define INIT_THREAD { \
62 	.ksp   = sizeof init_stack + (unsigned long)init_stack, \
63 	.pgdir = swapper_pg_dir, \
64 }
65 
66 /* Free all resources held by a thread. */
release_thread(struct task_struct * dead_task)67 static inline void release_thread(struct task_struct *dead_task)
68 {
69 }
70 
71 unsigned long __get_wchan(struct task_struct *p);
72 
73 /* The size allocated for kernel stacks. This _must_ be a power of two! */
74 # define KERNEL_STACK_SIZE	0x2000
75 
76 /* Return some info about the user process TASK.  */
77 #  define task_tos(task)	((unsigned long)(task) + KERNEL_STACK_SIZE)
78 #  define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
79 
80 #  define task_pt_regs_plus_args(tsk) \
81 	((void *)task_pt_regs(tsk))
82 
83 #  define task_sp(task)	(task_regs(task)->r1)
84 #  define task_pc(task)	(task_regs(task)->pc)
85 /* Grotty old names for some.  */
86 #  define KSTK_EIP(task)	(task_pc(task))
87 #  define KSTK_ESP(task)	(task_sp(task))
88 
89 #  define STACK_TOP	TASK_SIZE
90 #  define STACK_TOP_MAX	STACK_TOP
91 
92 #ifdef CONFIG_DEBUG_FS
93 extern struct dentry *of_debugfs_root;
94 #endif
95 
96 #  endif /* __ASSEMBLY__ */
97 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */
98