1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * OpenRISC Linux
4  *
5  * Linux architectural port borrowing liberally from similar works of
6  * others.  All original copyrights apply as per the original source
7  * declaration.
8  *
9  * OpenRISC implementation:
10  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12  * et al.
13  */
14 
15 #ifndef __ASM_OPENRISC_PROCESSOR_H
16 #define __ASM_OPENRISC_PROCESSOR_H
17 
18 #include <asm/spr_defs.h>
19 #include <asm/page.h>
20 #include <asm/ptrace.h>
21 
22 #define STACK_TOP       TASK_SIZE
23 #define STACK_TOP_MAX	STACK_TOP
24 /* Kernel and user SR register setting */
25 #define KERNEL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
26 		   | SPR_SR_DCE | SPR_SR_SM)
27 #define USER_SR   (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
28 		   | SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE)
29 
30 /*
31  * User space process size. This is hardcoded into a few places,
32  * so don't change it unless you know what you are doing.
33  */
34 
35 #define TASK_SIZE       (0x80000000UL)
36 
37 /* This decides where the kernel will search for a free chunk of vm
38  * space during mmap's.
39  */
40 #define TASK_UNMAPPED_BASE      (TASK_SIZE / 8 * 3)
41 
42 #ifndef __ASSEMBLY__
43 
44 struct task_struct;
45 
46 struct thread_struct {
47 };
48 
49 /*
50  * At user->kernel entry, the pt_regs struct is stacked on the top of the
51  * kernel-stack.  This macro allows us to find those regs for a task.
52  * Notice that subsequent pt_regs stackings, like recursive interrupts
53  * occurring while we're in the kernel, won't affect this - only the first
54  * user->kernel transition registers are reached by this (i.e. not regs
55  * for running signal handler)
56  */
57 #define user_regs(thread_info)  (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE - STACK_FRAME_OVERHEAD)) - 1)
58 
59 /*
60  * Dito but for the currently running task
61  */
62 
63 #define task_pt_regs(task) user_regs(task_thread_info(task))
64 
65 #define INIT_SP         (sizeof(init_stack) + (unsigned long) &init_stack)
66 
67 #define INIT_THREAD  { }
68 
69 
70 #define KSTK_EIP(tsk)   (task_pt_regs(tsk)->pc)
71 #define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
72 
73 
74 void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
75 unsigned long __get_wchan(struct task_struct *p);
76 void show_registers(struct pt_regs *regs);
77 
78 #define cpu_relax()     barrier()
79 
80 #endif /* __ASSEMBLY__ */
81 #endif /* __ASM_OPENRISC_PROCESSOR_H */
82