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