xref: /openbmc/linux/arch/arm/include/asm/processor.h (revision 565d76cb)
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/hw_breakpoint.h>
23 #include <asm/ptrace.h>
24 #include <asm/types.h>
25 
26 #ifdef __KERNEL__
27 #define STACK_TOP	((current->personality & ADDR_LIMIT_32BIT) ? \
28 			 TASK_SIZE : TASK_SIZE_26)
29 #define STACK_TOP_MAX	TASK_SIZE
30 #endif
31 
32 struct debug_info {
33 #ifdef CONFIG_HAVE_HW_BREAKPOINT
34 	struct perf_event	*hbp[ARM_MAX_HBP_SLOTS];
35 #endif
36 };
37 
38 struct thread_struct {
39 							/* fault info	  */
40 	unsigned long		address;
41 	unsigned long		trap_no;
42 	unsigned long		error_code;
43 							/* debugging	  */
44 	struct debug_info	debug;
45 };
46 
47 #define INIT_THREAD  {	}
48 
49 #ifdef CONFIG_MMU
50 #define nommu_start_thread(regs) do { } while (0)
51 #else
52 #define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
53 #endif
54 
55 #define start_thread(regs,pc,sp)					\
56 ({									\
57 	unsigned long *stack = (unsigned long *)sp;			\
58 	set_fs(USER_DS);						\
59 	memset(regs->uregs, 0, sizeof(regs->uregs));			\
60 	if (current->personality & ADDR_LIMIT_32BIT)			\
61 		regs->ARM_cpsr = USR_MODE;				\
62 	else								\
63 		regs->ARM_cpsr = USR26_MODE;				\
64 	if (elf_hwcap & HWCAP_THUMB && pc & 1)				\
65 		regs->ARM_cpsr |= PSR_T_BIT;				\
66 	regs->ARM_cpsr |= PSR_ENDSTATE;					\
67 	regs->ARM_pc = pc & ~1;		/* pc */			\
68 	regs->ARM_sp = sp;		/* sp */			\
69 	regs->ARM_r2 = stack[2];	/* r2 (envp) */			\
70 	regs->ARM_r1 = stack[1];	/* r1 (argv) */			\
71 	regs->ARM_r0 = stack[0];	/* r0 (argc) */			\
72 	nommu_start_thread(regs);					\
73 })
74 
75 /* Forward declaration, a strange C thing */
76 struct task_struct;
77 
78 /* Free all resources held by a thread. */
79 extern void release_thread(struct task_struct *);
80 
81 /* Prepare to copy thread state - unlazy all lazy status */
82 #define prepare_to_copy(tsk)	do { } while (0)
83 
84 unsigned long get_wchan(struct task_struct *p);
85 
86 #if __LINUX_ARM_ARCH__ == 6 || defined(CONFIG_ARM_ERRATA_754327)
87 #define cpu_relax()			smp_mb()
88 #else
89 #define cpu_relax()			barrier()
90 #endif
91 
92 /*
93  * Create a new kernel thread
94  */
95 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
96 
97 #define task_pt_regs(p) \
98 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
99 
100 #define KSTK_EIP(tsk)	task_pt_regs(tsk)->ARM_pc
101 #define KSTK_ESP(tsk)	task_pt_regs(tsk)->ARM_sp
102 
103 /*
104  * Prefetching support - only ARMv5.
105  */
106 #if __LINUX_ARM_ARCH__ >= 5
107 
108 #define ARCH_HAS_PREFETCH
109 static inline void prefetch(const void *ptr)
110 {
111 	__asm__ __volatile__(
112 		"pld\t%a0"
113 		:
114 		: "p" (ptr)
115 		: "cc");
116 }
117 
118 #define ARCH_HAS_PREFETCHW
119 #define prefetchw(ptr)	prefetch(ptr)
120 
121 #define ARCH_HAS_SPINLOCK_PREFETCH
122 #define spin_lock_prefetch(x) do { } while (0)
123 
124 #endif
125 
126 #endif
127 
128 #endif /* __ASM_ARM_PROCESSOR_H */
129