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 <linux/config.h>
  14 #include <asm/system.h>
  15 #include <asm/page.h>
  16 #include <asm/ptrace.h>
  17 #include <asm/arch/processor.h>
  18
  19 struct task_struct;
  20
  21 /* This decides where the kernel will search for a free chunk of vm
  22  * space during mmap's.
  23  */
  24 #define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 3))
  25
  26 /* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
  27  * normally, the stack is found by doing something like p + THREAD_SIZE
  28  * in CRIS, a page is 8192 bytes, which seems like a sane size
  29  */
  30
  31 #define THREAD_SIZE       PAGE_SIZE
  32 #define KERNEL_STACK_SIZE PAGE_SIZE
  33
  34 /*
  35  * At user->kernel entry, the pt_regs struct is stacked on the top of the kernel-stack.
  36  * This macro allows us to find those regs for a task.
  37  * Notice that subsequent pt_regs stackings, like recursive interrupts occurring while
  38  * we're in the kernel, won't affect this - only the first user->kernel transition
  39  * registers are reached by this.
  40  */
  41
  42 #define user_regs(thread_info) (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE)) - 1)
  43
  44 /*
  45  * Dito but for the currently running task
  46  */
  47
  48 #define task_pt_regs(task) user_regs(task_thread_info(task))
  49 #define current_regs() task_pt_regs(current)
  50
  51 static inline void prepare_to_copy(struct task_struct *tsk)
  52 {
  53 }
  54
  55 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
  56
  57 unsigned long get_wchan(struct task_struct *p);
  58
  59 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
  60
  61 extern unsigned long thread_saved_pc(struct task_struct *tsk);
  62
  63 /* Free all resources held by a thread. */
  64 static inline void release_thread(struct task_struct *dead_task)
  65 {
  66         /* Nothing needs to be done.  */
  67 }
  68
  69 #define init_stack      (init_thread_union.stack)
  70
  71 #define cpu_relax()     barrier()
  72
  73 #endif /* __ASM_CRIS_PROCESSOR_H */