1 /*
2  *  linux/include/asm-arm/proc-armo/processor.h
3  *
4  *  Copyright (C) 1996 Russell King.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  *  Changelog:
11  *   27-06-1996	RMK	Created
12  *   10-10-1996	RMK	Brought up to date with SA110
13  *   26-09-1996	RMK	Added 'EXTRA_THREAD_STRUCT*'
14  *   28-09-1996	RMK	Moved start_thread into the processor dependencies
15  *   11-01-1998	RMK	Added new uaccess_t
16  *   09-09-1998	PJB	Delete redundant `wp_works_ok'
17  *   30-05-1999	PJB	Save sl across context switches
18  */
19 #ifndef __ASM_PROC_PROCESSOR_H
20 #define __ASM_PROC_PROCESSOR_H
21 
22 #include <linux/string.h>
23 
24 #define KERNEL_STACK_SIZE 4096
25 
26 struct context_save_struct {
27 	unsigned long r4;
28 	unsigned long r5;
29 	unsigned long r6;
30 	unsigned long r7;
31 	unsigned long r8;
32 	unsigned long r9;
33 	unsigned long sl;
34 	unsigned long fp;
35 	unsigned long pc;
36 };
37 
38 #define INIT_CSS (struct context_save_struct){ 0, 0, 0, 0, 0, 0, 0, 0, SVC26_MODE }
39 
40 typedef struct {
41 	void (*put_byte)(void);			/* Special calling convention */
42 	void (*get_byte)(void);			/* Special calling convention */
43 	void (*put_half)(void);			/* Special calling convention */
44 	void (*get_half)(void);			/* Special calling convention */
45 	void (*put_word)(void);			/* Special calling convention */
46 	void (*get_word)(void);			/* Special calling convention */
47 	unsigned long (*copy_from_user)(void *to, const void *from, unsigned long sz);
48 	unsigned long (*copy_to_user)(void *to, const void *from, unsigned long sz);
49 	unsigned long (*clear_user)(void *addr, unsigned long sz);
50 	unsigned long (*strncpy_from_user)(char *to, const char *from, unsigned long sz);
51 	unsigned long (*strnlen_user)(const char *s, long n);
52 } uaccess_t;
53 
54 extern uaccess_t uaccess_user, uaccess_kernel;
55 
56 #define EXTRA_THREAD_STRUCT							\
57 	uaccess_t	*uaccess;		/* User access functions*/
58 
59 #define EXTRA_THREAD_STRUCT_INIT		\
60 	.uaccess	= &uaccess_kernel,
61 
62 #define start_thread(regs,pc,sp)					\
63 ({									\
64 	unsigned long *stack = (unsigned long *)sp;			\
65 	set_fs(USER_DS);						\
66 	memzero(regs->uregs, sizeof (regs->uregs));			\
67 	regs->ARM_pc = pc;		/* pc */			\
68 	regs->ARM_sp = sp;		/* sp */			\
69 	regs->ARM_r2 = stack[2];	/* r2 (envp) */			\
70 	regs->ARM_r1 = stack[1];	/* r1 (argv) */			\
71 	regs->ARM_r0 = stack[0];	/* r0 (argc) */			\
72 })
73 
74 #define KSTK_EIP(tsk)	(((unsigned long *)(4096+(unsigned long)(tsk)))[1020])
75 #define KSTK_ESP(tsk)	(((unsigned long *)(4096+(unsigned long)(tsk)))[1018])
76 
77 /* Allocation and freeing of basic task resources. */
78 /*
79  * NOTE! The task struct and the stack go together
80  */
81 extern unsigned long get_page_8k(int priority);
82 extern void free_page_8k(unsigned long page);
83 
84 #define ll_alloc_task_struct()	((struct task_struct *)get_page_8k(GFP_KERNEL))
85 #define ll_free_task_struct(p)  free_page_8k((unsigned long)(p))
86 
87 #endif
88