xref: /linux/arch/alpha/include/asm/processor.h (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /*
2  * include/asm-alpha/processor.h
3  *
4  * Copyright (C) 1994 Linus Torvalds
5  */
6 
7 #ifndef __ASM_ALPHA_PROCESSOR_H
8 #define __ASM_ALPHA_PROCESSOR_H
9 
10 #include <linux/personality.h>	/* for ADDR_LIMIT_32BIT */
11 
12 /*
13  * Returns current instruction pointer ("program counter").
14  */
15 #define current_text_addr() \
16   ({ void *__pc; __asm__ ("br %0,.+4" : "=r"(__pc)); __pc; })
17 
18 /*
19  * We have a 42-bit user address space: 4TB user VM...
20  */
21 #define TASK_SIZE (0x40000000000UL)
22 
23 #define STACK_TOP \
24   (current->personality & ADDR_LIMIT_32BIT ? 0x80000000 : 0x00120000000UL)
25 
26 #define STACK_TOP_MAX	0x00120000000UL
27 
28 /* This decides where the kernel will search for a free chunk of vm
29  * space during mmap's.
30  */
31 #define TASK_UNMAPPED_BASE \
32   ((current->personality & ADDR_LIMIT_32BIT) ? 0x40000000 : TASK_SIZE / 2)
33 
34 typedef struct {
35 	unsigned long seg;
36 } mm_segment_t;
37 
38 /* This is dead.  Everything has been moved to thread_info.  */
39 struct thread_struct { };
40 #define INIT_THREAD  { }
41 
42 /* Return saved PC of a blocked thread.  */
43 struct task_struct;
44 extern unsigned long thread_saved_pc(struct task_struct *);
45 
46 /* Do necessary setup to start up a newly executed thread.  */
47 extern void start_thread(struct pt_regs *, unsigned long, unsigned long);
48 
49 /* Free all resources held by a thread. */
50 extern void release_thread(struct task_struct *);
51 
52 /* Create a kernel thread without removing it from tasklists.  */
53 extern long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
54 
55 unsigned long get_wchan(struct task_struct *p);
56 
57 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
58 
59 #define KSTK_ESP(tsk) \
60   ((tsk) == current ? rdusp() : task_thread_info(tsk)->pcb.usp)
61 
62 #define cpu_relax()	barrier()
63 
64 #define ARCH_HAS_PREFETCH
65 #define ARCH_HAS_PREFETCHW
66 #define ARCH_HAS_SPINLOCK_PREFETCH
67 
68 #ifndef CONFIG_SMP
69 /* Nothing to prefetch. */
70 #define spin_lock_prefetch(lock)  	do { } while (0)
71 #endif
72 
73 extern inline void prefetch(const void *ptr)
74 {
75 	__builtin_prefetch(ptr, 0, 3);
76 }
77 
78 extern inline void prefetchw(const void *ptr)
79 {
80 	__builtin_prefetch(ptr, 1, 3);
81 }
82 
83 #ifdef CONFIG_SMP
84 extern inline void spin_lock_prefetch(const void *ptr)
85 {
86 	__builtin_prefetch(ptr, 1, 3);
87 }
88 #endif
89 
90 #endif /* __ASM_ALPHA_PROCESSOR_H */
91