arch/microblaze/include/asm/processor.h

   1 /*
   2  * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
   3  * Copyright (C) 2008-2009 PetaLogix
   4  * Copyright (C) 2006 Atmark Techno, Inc.
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License. See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10
  11 #ifndef _ASM_MICROBLAZE_PROCESSOR_H
  12 #define _ASM_MICROBLAZE_PROCESSOR_H
  13
  14 #include <asm/ptrace.h>
  15 #include <asm/setup.h>
  16 #include <asm/registers.h>
  17 #include <asm/segment.h>
  18 #include <asm/entry.h>
  19 #include <asm/current.h>
  20
  21 # ifndef __ASSEMBLY__
  22 /* from kernel/cpu/mb.c */
  23 extern const struct seq_operations cpuinfo_op;
  24
  25 # define cpu_relax()            barrier()
  26 # define cpu_sleep()            do {} while (0)
  27 # define prepare_to_copy(tsk)   do {} while (0)
  28
  29 #define task_pt_regs(tsk) \
  30                 (((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)
  31
  32 /* Do necessary setup to start up a newly executed thread. */
  33 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);
  34
  35 # endif /* __ASSEMBLY__ */
  36
  37 # ifndef CONFIG_MMU
  38 /*
  39  * User space process size: memory size
  40  *
  41  * TASK_SIZE on MMU cpu is usually 1GB. However, on no-MMU arch, both
  42  * user processes and the kernel is on the same memory region. They
  43  * both share the memory space and that is limited by the amount of
  44  * physical memory. thus, we set TASK_SIZE == amount of total memory.
  45  */
  46 # define TASK_SIZE      (0x81000000 - 0x80000000)
  47
  48 /*
  49  * Default implementation of macro that returns current
  50  * instruction pointer ("program counter").
  51  */
  52 # define current_text_addr() ({ __label__ _l; _l: &&_l; })
  53
  54 /*
  55  * This decides where the kernel will search for a free chunk of vm
  56  * space during mmap's. We won't be using it
  57  */
  58 # define TASK_UNMAPPED_BASE     0
  59
  60 /* definition in include/linux/sched.h */
  61 struct task_struct;
  62
  63 /* thread_struct is gone. use thread_info instead. */
  64 struct thread_struct { };
  65 # define INIT_THREAD    { }
  66
  67 /* Free all resources held by a thread. */
  68 static inline void release_thread(struct task_struct *dead_task)
  69 {
  70 }
  71
  72 /* Free all resources held by a thread. */
  73 static inline void exit_thread(void)
  74 {
  75 }
  76
  77 extern unsigned long thread_saved_pc(struct task_struct *t);
  78
  79 extern unsigned long get_wchan(struct task_struct *p);
  80
  81 /*
  82  * create a kernel thread without removing it from tasklists
  83  */
  84 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
  85
  86 # define KSTK_EIP(tsk)  (0)
  87 # define KSTK_ESP(tsk)  (0)
  88
  89 # else /* CONFIG_MMU */
  90
  91 /*
  92  * This is used to define STACK_TOP, and with MMU it must be below
  93  * kernel base to select the correct PGD when handling MMU exceptions.
  94  */
  95 # define TASK_SIZE      (CONFIG_KERNEL_START)
  96
  97 /*
  98  * This decides where the kernel will search for a free chunk of vm
  99  * space during mmap's.
 100  */
 101 # define TASK_UNMAPPED_BASE     (TASK_SIZE / 8 * 3)
 102
 103 # define THREAD_KSP     0
 104
 105 #  ifndef __ASSEMBLY__
 106
 107 /*
 108  * Default implementation of macro that returns current
 109  * instruction pointer ("program counter").
 110  */
 111 #  define current_text_addr()   ({ __label__ _l; _l: &&_l; })
 112
 113 /* If you change this, you must change the associated assembly-languages
 114  * constants defined below, THREAD_*.
 115  */
 116 struct thread_struct {
 117         /* kernel stack pointer (must be first field in structure) */
 118         unsigned long   ksp;
 119         unsigned long   ksp_limit;      /* if ksp <= ksp_limit stack overflow */
 120         void            *pgdir;         /* root of page-table tree */
 121         struct pt_regs  *regs;          /* Pointer to saved register state */
 122 };
 123
 124 #  define INIT_THREAD { \
 125         .ksp   = sizeof init_stack + (unsigned long)init_stack, \
 126         .pgdir = swapper_pg_dir, \
 127 }
 128
 129 /* Do necessary setup to start up a newly executed thread.  */
 130 void start_thread(struct pt_regs *regs,
 131                 unsigned long pc, unsigned long usp);
 132
 133 /* Free all resources held by a thread. */
 134 extern inline void release_thread(struct task_struct *dead_task)
 135 {
 136 }
 137
 138 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 139
 140 /* Free current thread data structures etc.  */
 141 static inline void exit_thread(void)
 142 {
 143 }
 144
 145 /* Return saved (kernel) PC of a blocked thread.  */
 146 #  define thread_saved_pc(tsk)  \
 147         ((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0)
 148
 149 unsigned long get_wchan(struct task_struct *p);
 150
 151 /* The size allocated for kernel stacks. This _must_ be a power of two! */
 152 # define KERNEL_STACK_SIZE      0x2000
 153
 154 /* Return some info about the user process TASK.  */
 155 #  define task_tos(task)        ((unsigned long)(task) + KERNEL_STACK_SIZE)
 156 #  define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
 157
 158 #  define task_pt_regs_plus_args(tsk) \
 159         (((void *)task_pt_regs(tsk)) - STATE_SAVE_ARG_SPACE)
 160
 161 #  define task_sp(task) (task_regs(task)->r1)
 162 #  define task_pc(task) (task_regs(task)->pc)
 163 /* Grotty old names for some.  */
 164 #  define KSTK_EIP(task)        (task_pc(task))
 165 #  define KSTK_ESP(task)        (task_sp(task))
 166
 167 /* FIXME */
 168 #  define deactivate_mm(tsk, mm)        do { } while (0)
 169
 170 #  define STACK_TOP     TASK_SIZE
 171 #  define STACK_TOP_MAX STACK_TOP
 172
 173 #  endif /* __ASSEMBLY__ */
 174 # endif /* CONFIG_MMU */
 175 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */