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