LXR linux-old/include/asm-alpha/processor.h

   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/* This decides where the kernel will search for a free chunk of vm
  24 * space during mmap's.
  25 */
  26#define TASK_UNMAPPED_BASE \
  27  ((current->personality & ADDR_LIMIT_32BIT) ? 0x40000000 : TASK_SIZE / 2)
  28
  29/*
  30 * Bus types
  31 */
  32#define EISA_bus 1
  33#define EISA_bus__is_a_macro /* for versions in ksyms.c */
  34#define MCA_bus 0
  35#define MCA_bus__is_a_macro /* for versions in ksyms.c */
  36
  37typedef struct {
  38        unsigned long seg;
  39} mm_segment_t;
  40
  41struct thread_struct {
  42        /* the fields below are used by PALcode and must match struct pcb: */
  43        unsigned long ksp;
  44        unsigned long usp;
  45        unsigned long ptbr;
  46        unsigned int pcc;
  47        unsigned int asn;
  48        unsigned long unique;
  49        /*
  50         * bit  0: floating point enable
  51         * bit 62: performance monitor enable
  52         */
  53        unsigned long pal_flags;
  54        unsigned long res1, res2;
  55
  56        /*
  57         * The fields below are Linux-specific:
  58         *
  59         * bit 1..5: IEEE_TRAP_ENABLE bits (see fpu.h)
  60         * bit 6..8: UAC bits (see sysinfo.h)
  61         * bit 17..21: IEEE_STATUS_MASK bits (see fpu.h)
  62         * bit 63: die_if_kernel recursion lock
  63         */
  64        unsigned long flags;
  65
  66        /* Perform syscall argument validation (get/set_fs). */
  67        mm_segment_t fs;
  68
  69        /* Breakpoint handling for ptrace.  */
  70        unsigned long bpt_addr[2];
  71        unsigned int bpt_insn[2];
  72        int bpt_nsaved;
  73};
  74
  75#define INIT_THREAD  { \
  76        0, 0, 0, \
  77        0, 0, 0, \
  78        0, 0, 0, \
  79        0, \
  80        KERNEL_DS \
  81}
  82
  83#define THREAD_SIZE (2*PAGE_SIZE)
  84
  85#include <asm/ptrace.h>
  86
  87/*
  88 * Return saved PC of a blocked thread.  This assumes the frame
  89 * pointer is the 6th saved long on the kernel stack and that the
  90 * saved return address is the first long in the frame.  This all
  91 * holds provided the thread blocked through a call to schedule() ($15
  92 * is the frame pointer in schedule() and $15 is saved at offset 48 by
  93 * entry.S:do_switch_stack).
  94 *
  95 * Under heavy swap load I've seen this lose in an ugly way.  So do
  96 * some extra sanity checking on the ranges we expect these pointers
  97 * to be in so that we can fail gracefully.  This is just for ps after
  98 * all.  -- r~
  99 */
 100extern inline unsigned long thread_saved_pc(struct thread_struct *t)
 101{
 102        unsigned long fp, sp = t->ksp, base = (unsigned long)t;
 103 
 104        if (sp > base && sp+6*8 < base + 16*1024) {
 105                fp = ((unsigned long*)sp)[6];
 106                if (fp > sp && fp < base + 16*1024)
 107                        return *(unsigned long *)fp;
 108        }
 109
 110        return 0;
 111}
 112
 113/* Do necessary setup to start up a newly executed thread.  */
 114extern void start_thread(struct pt_regs *, unsigned long, unsigned long);
 115
 116struct task_struct;
 117
 118/* Free all resources held by a thread. */
 119extern void release_thread(struct task_struct *);
 120
 121/* Create a kernel thread without removing it from tasklists.  */
 122extern long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 123
 124#define copy_segments(tsk, mm)          do { } while (0)
 125#define release_segments(mm)            do { } while (0)
 126
 127unsigned long get_wchan(struct task_struct *p);
 128
 129/* See arch/alpha/kernel/ptrace.c for details.  */
 130#define PT_REG(reg)     (PAGE_SIZE*2 - sizeof(struct pt_regs)           \
 131                         + (long)&((struct pt_regs *)0)->reg)
 132
 133#define SW_REG(reg)     (PAGE_SIZE*2 - sizeof(struct pt_regs)           \
 134                         - sizeof(struct switch_stack)                  \
 135                         + (long)&((struct switch_stack *)0)->reg)
 136
 137#define KSTK_EIP(tsk) \
 138    (*(unsigned long *)(PT_REG(pc) + (unsigned long)(tsk)))
 139
 140#define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 141
 142/* NOTE: The task struct and the stack go together!  */
 143#define alloc_task_struct() \
 144        ((struct task_struct *) __get_free_pages(GFP_KERNEL,1))
 145#define free_task_struct(p)     free_pages((unsigned long)(p),1)
 146#define get_task_struct(tsk)      atomic_inc(&virt_to_page(tsk)->count)
 147
 148#define init_task       (init_task_union.task)
 149#define init_stack      (init_task_union.stack)
 150
 151#define cpu_relax()     do { } while (0)
 152
 153#define ARCH_HAS_PREFETCH
 154#define ARCH_HAS_PREFETCHW
 155#define ARCH_HAS_SPINLOCK_PREFETCH
 156
 157extern inline void prefetch(const void *ptr)  
 158{ 
 159        __asm__ ("ldl $31,%0" : : "m"(*(char *)ptr)); 
 160}
 161
 162extern inline void prefetchw(const void *ptr)  
 163{
 164        __asm__ ("ldl $31,%0" : : "m"(*(char *)ptr)); 
 165}
 166
 167extern inline void spin_lock_prefetch(const void *ptr)  
 168{
 169        __asm__ ("ldl $31,%0" : : "m"(*(char *)ptr)); 
 170}
 171        
 172
 173
 174#endif /* __ASM_ALPHA_PROCESSOR_H */
 175