arch/cris/include/arch-v10/arch/processor.h

   1 #ifndef __ASM_CRIS_ARCH_PROCESSOR_H
   2 #define __ASM_CRIS_ARCH_PROCESSOR_H
   3
   4 /*
   5  * Default implementation of macro that returns current
   6  * instruction pointer ("program counter").
   7  */
   8 #define current_text_addr() ({void *pc; __asm__ ("move.d $pc,%0" : "=rm" (pc)); pc; })
   9
  10 /* CRIS has no problems with write protection */
  11 #define wp_works_ok 1
  12
  13 /* CRIS thread_struct. this really has nothing to do with the processor itself, since
  14  * CRIS does not do any hardware task-switching, but it's here for legacy reasons.
  15  * The thread_struct here is used when task-switching using _resume defined in entry.S.
  16  * The offsets here are hardcoded into _resume - if you change this struct, you need to
  17  * change them as well!!!
  18 */
  19
  20 struct thread_struct {
  21         unsigned long ksp;     /* kernel stack pointer */
  22         unsigned long usp;     /* user stack pointer */
  23         unsigned long dccr;    /* saved flag register */
  24 };
  25
  26 /*
  27  * User space process size. This is hardcoded into a few places,
  28  * so don't change it unless you know what you are doing.
  29  */
  30
  31 #ifdef CONFIG_CRIS_LOW_MAP
  32 #define TASK_SIZE       (0x50000000UL)   /* 1.25 GB */
  33 #else
  34 #define TASK_SIZE       (0xA0000000UL)   /* 2.56 GB */
  35 #endif
  36
  37 #define INIT_THREAD  { \
  38    0, 0, 0x20 }  /* ccr = int enable, nothing else */
  39
  40 #define KSTK_EIP(tsk)   \
  41 ({                      \
  42         unsigned long eip = 0;   \
  43         unsigned long regs = (unsigned long)task_pt_regs(tsk); \
  44         if (regs > PAGE_SIZE && \
  45                 virt_addr_valid(regs)) \
  46         eip = ((struct pt_regs *)regs)->irp; \
  47         eip; \
  48 })
  49
  50 /* give the thread a program location
  51  * set user-mode (The 'U' flag (User mode flag) is CCR/DCCR bit 8)
  52  * switch user-stackpointer
  53  */
  54
  55 #define start_thread(regs, ip, usp) do { \
  56         set_fs(USER_DS);      \
  57         regs->irp = ip;       \
  58         regs->dccr |= 1 << U_DCCR_BITNR; \
  59         wrusp(usp);           \
  60 } while(0)
  61
  62 /* Called when handling a kernel bus fault fixup.
  63  *
  64  * After a fixup we do not want to return by restoring the CPU-state
  65  * anymore, so switch frame-types (see ptrace.h)
  66  */
  67 #define arch_fixup(regs) \
  68    regs->frametype = CRIS_FRAME_NORMAL;
  69
  70 #endif