xref: /openbmc/linux/arch/arm/include/asm/processor.h (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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 union debug_insn {
33 	u32	arm;
34 	u16	thumb;
35 };
36 
37 struct debug_entry {
38 	u32			address;
39 	union debug_insn	insn;
40 };
41 
42 struct debug_info {
43 	int			nsaved;
44 	struct debug_entry	bp[2];
45 #ifdef CONFIG_HAVE_HW_BREAKPOINT
46 	struct perf_event	*hbp[ARM_MAX_HBP_SLOTS];
47 #endif
48 };
49 
50 struct thread_struct {
51 							/* fault info	  */
52 	unsigned long		address;
53 	unsigned long		trap_no;
54 	unsigned long		error_code;
55 							/* debugging	  */
56 	struct debug_info	debug;
57 };
58 
59 #define INIT_THREAD  {	}
60 
61 #ifdef CONFIG_MMU
62 #define nommu_start_thread(regs) do { } while (0)
63 #else
64 #define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
65 #endif
66 
67 #define start_thread(regs,pc,sp)					\
68 ({									\
69 	unsigned long *stack = (unsigned long *)sp;			\
70 	set_fs(USER_DS);						\
71 	memset(regs->uregs, 0, sizeof(regs->uregs));			\
72 	if (current->personality & ADDR_LIMIT_32BIT)			\
73 		regs->ARM_cpsr = USR_MODE;				\
74 	else								\
75 		regs->ARM_cpsr = USR26_MODE;				\
76 	if (elf_hwcap & HWCAP_THUMB && pc & 1)				\
77 		regs->ARM_cpsr |= PSR_T_BIT;				\
78 	regs->ARM_cpsr |= PSR_ENDSTATE;					\
79 	regs->ARM_pc = pc & ~1;		/* pc */			\
80 	regs->ARM_sp = sp;		/* sp */			\
81 	regs->ARM_r2 = stack[2];	/* r2 (envp) */			\
82 	regs->ARM_r1 = stack[1];	/* r1 (argv) */			\
83 	regs->ARM_r0 = stack[0];	/* r0 (argc) */			\
84 	nommu_start_thread(regs);					\
85 })
86 
87 /* Forward declaration, a strange C thing */
88 struct task_struct;
89 
90 /* Free all resources held by a thread. */
91 extern void release_thread(struct task_struct *);
92 
93 /* Prepare to copy thread state - unlazy all lazy status */
94 #define prepare_to_copy(tsk)	do { } while (0)
95 
96 unsigned long get_wchan(struct task_struct *p);
97 
98 #if __LINUX_ARM_ARCH__ == 6
99 #define cpu_relax()			smp_mb()
100 #else
101 #define cpu_relax()			barrier()
102 #endif
103 
104 /*
105  * Create a new kernel thread
106  */
107 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
108 
109 #define task_pt_regs(p) \
110 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
111 
112 #define KSTK_EIP(tsk)	task_pt_regs(tsk)->ARM_pc
113 #define KSTK_ESP(tsk)	task_pt_regs(tsk)->ARM_sp
114 
115 /*
116  * Prefetching support - only ARMv5.
117  */
118 #if __LINUX_ARM_ARCH__ >= 5
119 
120 #define ARCH_HAS_PREFETCH
121 static inline void prefetch(const void *ptr)
122 {
123 	__asm__ __volatile__(
124 		"pld\t%a0"
125 		:
126 		: "p" (ptr)
127 		: "cc");
128 }
129 
130 #define ARCH_HAS_PREFETCHW
131 #define prefetchw(ptr)	prefetch(ptr)
132 
133 #define ARCH_HAS_SPINLOCK_PREFETCH
134 #define spin_lock_prefetch(x) do { } while (0)
135 
136 #endif
137 
138 #endif
139 
140 #endif /* __ASM_ARM_PROCESSOR_H */
141