1/*
2 *  linux/include/asm-arm/processor.h
3 *
4 *  Copyright (C) 1995-1999 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
11#ifndef __ASM_ARM_PROCESSOR_H
12#define __ASM_ARM_PROCESSOR_H
13
14/*
15 * Default implementation of macro that returns current
16 * instruction pointer ("program counter").
17 */
18#define current_text_addr() ({ __label__ _l; _l: &&_l;})
19
20#ifdef __KERNEL__
21
22#include <asm/ptrace.h>
23#include <asm/procinfo.h>
24#include <asm/types.h>
25
26union debug_insn {
27	u32	arm;
28	u16	thumb;
29};
30
31struct debug_entry {
32	u32			address;
33	union debug_insn	insn;
34};
35
36struct debug_info {
37	int			nsaved;
38	struct debug_entry	bp[2];
39};
40
41struct thread_struct {
42							/* fault info	  */
43	unsigned long		address;
44	unsigned long		trap_no;
45	unsigned long		error_code;
46							/* debugging	  */
47	struct debug_info	debug;
48};
49
50#define INIT_THREAD  {	}
51
52#ifdef CONFIG_MMU
53#define nommu_start_thread(regs) do { } while (0)
54#else
55#define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
56#endif
57
58#define start_thread(regs,pc,sp)					\
59({									\
60	unsigned long *stack = (unsigned long *)sp;			\
61	set_fs(USER_DS);						\
62	memzero(regs->uregs, sizeof(regs->uregs));			\
63	if (current->personality & ADDR_LIMIT_32BIT)			\
64		regs->ARM_cpsr = USR_MODE;				\
65	else								\
66		regs->ARM_cpsr = USR26_MODE;				\
67	if (elf_hwcap & HWCAP_THUMB && pc & 1)				\
68		regs->ARM_cpsr |= PSR_T_BIT;				\
69	regs->ARM_pc = pc & ~1;		/* pc */			\
70	regs->ARM_sp = sp;		/* sp */			\
71	regs->ARM_r2 = stack[2];	/* r2 (envp) */			\
72	regs->ARM_r1 = stack[1];	/* r1 (argv) */			\
73	regs->ARM_r0 = stack[0];	/* r0 (argc) */			\
74	nommu_start_thread(regs);					\
75})
76
77/* Forward declaration, a strange C thing */
78struct task_struct;
79
80/* Free all resources held by a thread. */
81extern void release_thread(struct task_struct *);
82
83/* Prepare to copy thread state - unlazy all lazy status */
84#define prepare_to_copy(tsk)	do { } while (0)
85
86unsigned long get_wchan(struct task_struct *p);
87
88#define cpu_relax()			barrier()
89
90/*
91 * Create a new kernel thread
92 */
93extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
94
95#define task_pt_regs(p) \
96	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
97
98#define KSTK_EIP(tsk)	task_pt_regs(tsk)->ARM_pc
99#define KSTK_ESP(tsk)	task_pt_regs(tsk)->ARM_sp
100
101/*
102 * Prefetching support - only ARMv5.
103 */
104#if __LINUX_ARM_ARCH__ >= 5
105
106#define ARCH_HAS_PREFETCH
107#define prefetch(ptr)				\
108	({					\
109		__asm__ __volatile__(		\
110		"pld\t%0"			\
111		:				\
112		: "o" (*(char *)(ptr))		\
113		: "cc");			\
114	})
115
116#define ARCH_HAS_PREFETCHW
117#define prefetchw(ptr)	prefetch(ptr)
118
119#define ARCH_HAS_SPINLOCK_PREFETCH
120#define spin_lock_prefetch(x) do { } while (0)
121
122#endif
123
124#endif
125
126#endif /* __ASM_ARM_PROCESSOR_H */
127