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

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __ASM_CRIS_ARCH_PROCESSOR_H
   3 #define __ASM_CRIS_ARCH_PROCESSOR_H
   4
   5 /*
   6  * Default implementation of macro that returns current
   7  * instruction pointer ("program counter").
   8  */
   9 #define current_text_addr() ({void *pc; __asm__ ("move.d $pc,%0" : "=rm" (pc)); pc; })
  10
  11 /* CRIS has no problems with write protection */
  12 #define wp_works_ok 1
  13
  14 /* CRIS thread_struct. this really has nothing to do with the processor itself, since
  15  * CRIS does not do any hardware task-switching, but it's here for legacy reasons.
  16  * The thread_struct here is used when task-switching using _resume defined in entry.S.
  17  * The offsets here are hardcoded into _resume - if you change this struct, you need to
  18  * change them as well!!!
  19 */
  20
  21 struct thread_struct {
  22         unsigned long ksp;     /* kernel stack pointer */
  23         unsigned long usp;     /* user stack pointer */
  24         unsigned long dccr;    /* saved flag register */
  25 };
  26
  27 /*
  28  * User space process size. This is hardcoded into a few places,
  29  * so don't change it unless you know what you are doing.
  30  */
  31
  32 #ifdef CONFIG_CRIS_LOW_MAP
  33 #define TASK_SIZE       (0x50000000UL)   /* 1.25 GB */
  34 #else
  35 #define TASK_SIZE       (0xA0000000UL)   /* 2.56 GB */
  36 #endif
  37
  38 #define INIT_THREAD  { \
  39    0, 0, 0x20 }  /* ccr = int enable, nothing else */
  40
  41 #define KSTK_EIP(tsk)   \
  42 ({                      \
  43         unsigned long eip = 0;   \
  44         unsigned long regs = (unsigned long)task_pt_regs(tsk); \
  45         if (regs > PAGE_SIZE && \
  46                 virt_addr_valid(regs)) \
  47         eip = ((struct pt_regs *)regs)->irp; \
  48         eip; \
  49 })
  50
  51 /* give the thread a program location
  52  * set user-mode (The 'U' flag (User mode flag) is CCR/DCCR bit 8)
  53  * switch user-stackpointer
  54  */
  55
  56 #define start_thread(regs, ip, usp) do { \
  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