include/asm-cris/processor.h

   1 /*
   2  * include/asm-cris/processor.h
   3  *
   4  * Copyright (C) 2000, 2001 Axis Communications AB
   5  *
   6  * Authors:         Bjorn Wesen        Initial version
   7  *
   8  */
   9
  10 #ifndef __ASM_CRIS_PROCESSOR_H
  11 #define __ASM_CRIS_PROCESSOR_H
  12
  13 #include <asm/system.h>
  14 #include <asm/page.h>
  15 #include <asm/ptrace.h>
  16 #include <asm/arch/processor.h>
  17
  18 struct task_struct;
  19
  20 #define STACK_TOP       TASK_SIZE
  21 #define STACK_TOP_MAX   STACK_TOP
  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      (PAGE_ALIGN(TASK_SIZE / 3))
  27
  28 /* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
  29  * normally, the stack is found by doing something like p + THREAD_SIZE
  30  * in CRIS, a page is 8192 bytes, which seems like a sane size
  31  */
  32
  33 #define THREAD_SIZE       PAGE_SIZE
  34 #define KERNEL_STACK_SIZE PAGE_SIZE
  35
  36 /*
  37  * At user->kernel entry, the pt_regs struct is stacked on the top of the kernel-stack.
  38  * This macro allows us to find those regs for a task.
  39  * Notice that subsequent pt_regs stackings, like recursive interrupts occurring while
  40  * we're in the kernel, won't affect this - only the first user->kernel transition
  41  * registers are reached by this.
  42  */
  43
  44 #define user_regs(thread_info) (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE)) - 1)
  45
  46 /*
  47  * Dito but for the currently running task
  48  */
  49
  50 #define task_pt_regs(task) user_regs(task_thread_info(task))
  51 #define current_regs() task_pt_regs(current)
  52
  53 static inline void prepare_to_copy(struct task_struct *tsk)
  54 {
  55 }
  56
  57 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
  58
  59 unsigned long get_wchan(struct task_struct *p);
  60
  61 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
  62
  63 extern unsigned long thread_saved_pc(struct task_struct *tsk);
  64
  65 /* Free all resources held by a thread. */
  66 static inline void release_thread(struct task_struct *dead_task)
  67 {
  68         /* Nothing needs to be done.  */
  69 }
  70
  71 #define init_stack      (init_thread_union.stack)
  72
  73 #define cpu_relax()     barrier()
  74
  75 #endif /* __ASM_CRIS_PROCESSOR_H */