xref: /openbmc/linux/arch/arm/include/asm/processor.h (revision e8e0929d)
1 /*
2  *  arch/arm/include/asm/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 
25 #ifdef __KERNEL__
26 #define STACK_TOP	((current->personality & ADDR_LIMIT_32BIT) ? \
27 			 TASK_SIZE : TASK_SIZE_26)
28 #define STACK_TOP_MAX	TASK_SIZE
29 #endif
30 
31 union debug_insn {
32 	u32	arm;
33 	u16	thumb;
34 };
35 
36 struct debug_entry {
37 	u32			address;
38 	union debug_insn	insn;
39 };
40 
41 struct debug_info {
42 	int			nsaved;
43 	struct debug_entry	bp[2];
44 };
45 
46 struct thread_struct {
47 							/* fault info	  */
48 	unsigned long		address;
49 	unsigned long		trap_no;
50 	unsigned long		error_code;
51 							/* debugging	  */
52 	struct debug_info	debug;
53 };
54 
55 #define INIT_THREAD  {	}
56 
57 #ifdef CONFIG_MMU
58 #define nommu_start_thread(regs) do { } while (0)
59 #else
60 #define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
61 #endif
62 
63 #define start_thread(regs,pc,sp)					\
64 ({									\
65 	unsigned long *stack = (unsigned long *)sp;			\
66 	set_fs(USER_DS);						\
67 	memset(regs->uregs, 0, sizeof(regs->uregs));			\
68 	if (current->personality & ADDR_LIMIT_32BIT)			\
69 		regs->ARM_cpsr = USR_MODE;				\
70 	else								\
71 		regs->ARM_cpsr = USR26_MODE;				\
72 	if (elf_hwcap & HWCAP_THUMB && pc & 1)				\
73 		regs->ARM_cpsr |= PSR_T_BIT;				\
74 	regs->ARM_cpsr |= PSR_ENDSTATE;					\
75 	regs->ARM_pc = pc & ~1;		/* pc */			\
76 	regs->ARM_sp = sp;		/* sp */			\
77 	regs->ARM_r2 = stack[2];	/* r2 (envp) */			\
78 	regs->ARM_r1 = stack[1];	/* r1 (argv) */			\
79 	regs->ARM_r0 = stack[0];	/* r0 (argc) */			\
80 	nommu_start_thread(regs);					\
81 })
82 
83 /* Forward declaration, a strange C thing */
84 struct task_struct;
85 
86 /* Free all resources held by a thread. */
87 extern void release_thread(struct task_struct *);
88 
89 /* Prepare to copy thread state - unlazy all lazy status */
90 #define prepare_to_copy(tsk)	do { } while (0)
91 
92 unsigned long get_wchan(struct task_struct *p);
93 
94 #define cpu_relax()			barrier()
95 
96 /*
97  * Create a new kernel thread
98  */
99 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
100 
101 #define task_pt_regs(p) \
102 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
103 
104 #define KSTK_EIP(tsk)	task_pt_regs(tsk)->ARM_pc
105 #define KSTK_ESP(tsk)	task_pt_regs(tsk)->ARM_sp
106 
107 /*
108  * Prefetching support - only ARMv5.
109  */
110 #if __LINUX_ARM_ARCH__ >= 5
111 
112 #define ARCH_HAS_PREFETCH
113 static inline void prefetch(const void *ptr)
114 {
115 	__asm__ __volatile__(
116 		"pld\t%a0"
117 		:
118 		: "p" (ptr)
119 		: "cc");
120 }
121 
122 #define ARCH_HAS_PREFETCHW
123 #define prefetchw(ptr)	prefetch(ptr)
124 
125 #define ARCH_HAS_SPINLOCK_PREFETCH
126 #define spin_lock_prefetch(x) do { } while (0)
127 
128 #endif
129 
130 #endif
131 
132 #endif /* __ASM_ARM_PROCESSOR_H */
133