1 /*
2  * OpenRISC Linux
3  *
4  * Linux architectural port borrowing liberally from similar works of
5  * others.  All original copyrights apply as per the original source
6  * declaration.
7  *
8  * OpenRISC implementation:
9  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
10  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
11  * et al.
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  */
18 
19 #ifndef __ASM_OPENRISC_PROCESSOR_H
20 #define __ASM_OPENRISC_PROCESSOR_H
21 
22 #include <asm/spr_defs.h>
23 #include <asm/page.h>
24 #include <asm/ptrace.h>
25 
26 #define STACK_TOP       TASK_SIZE
27 #define STACK_TOP_MAX	STACK_TOP
28 /* Kernel and user SR register setting */
29 #define KERNEL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
30 		   | SPR_SR_DCE | SPR_SR_SM)
31 #define USER_SR   (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
32 		   | SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE)
33 
34 /*
35  * User space process size. This is hardcoded into a few places,
36  * so don't change it unless you know what you are doing.
37  */
38 
39 #define TASK_SIZE       (0x80000000UL)
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 #ifndef __ASSEMBLY__
47 
48 struct task_struct;
49 
50 struct thread_struct {
51 };
52 
53 /*
54  * At user->kernel entry, the pt_regs struct is stacked on the top of the
55  * kernel-stack.  This macro allows us to find those regs for a task.
56  * Notice that subsequent pt_regs stackings, like recursive interrupts
57  * occurring while we're in the kernel, won't affect this - only the first
58  * user->kernel transition registers are reached by this (i.e. not regs
59  * for running signal handler)
60  */
61 #define user_regs(thread_info)  (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE - STACK_FRAME_OVERHEAD)) - 1)
62 
63 /*
64  * Dito but for the currently running task
65  */
66 
67 #define task_pt_regs(task) user_regs(task_thread_info(task))
68 
69 #define INIT_SP         (sizeof(init_stack) + (unsigned long) &init_stack)
70 
71 #define INIT_THREAD  { }
72 
73 
74 #define KSTK_EIP(tsk)   (task_pt_regs(tsk)->pc)
75 #define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
76 
77 
78 void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
79 void release_thread(struct task_struct *);
80 unsigned long get_wchan(struct task_struct *p);
81 
82 #define cpu_relax()     barrier()
83 
84 #endif /* __ASSEMBLY__ */
85 #endif /* __ASM_OPENRISC_PROCESSOR_H */
86