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/entry.h>
  18 #include <asm/current.h>
  19
  20 # ifndef __ASSEMBLY__
  21 /* from kernel/cpu/mb.c */
  22 extern const struct seq_operations cpuinfo_op;
  23
  24 # define cpu_relax()            barrier()
  25 # define cpu_relax_lowlatency() cpu_relax()
  26
  27 #define task_pt_regs(tsk) \
  28                 (((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)
  29
  30 /* Do necessary setup to start up a newly executed thread. */
  31 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);
  32
  33 extern void ret_from_fork(void);
  34 extern void ret_from_kernel_thread(void);
  35
  36 # endif /* __ASSEMBLY__ */
  37
  38 # ifndef CONFIG_MMU
  39 /*
  40  * User space process size: memory size
  41  *
  42  * TASK_SIZE on MMU cpu is usually 1GB. However, on no-MMU arch, both
  43  * user processes and the kernel is on the same memory region. They
  44  * both share the memory space and that is limited by the amount of
  45  * physical memory. thus, we set TASK_SIZE == amount of total memory.
  46  */
  47 # define TASK_SIZE      (0x81000000 - 0x80000000)
  48
  49 /*
  50  * Default implementation of macro that returns current
  51  * instruction pointer ("program counter").
  52  */
  53 # define current_text_addr() ({ __label__ _l; _l: &&_l; })
  54
  55 /*
  56  * This decides where the kernel will search for a free chunk of vm
  57  * space during mmap's. We won't be using it
  58  */
  59 # define TASK_UNMAPPED_BASE     0
  60
  61 /* definition in include/linux/sched.h */
  62 struct task_struct;
  63
  64 /* thread_struct is gone. use thread_info instead. */
  65 struct thread_struct { };
  66 # define INIT_THREAD    { }
  67
  68 /* Free all resources held by a thread. */
  69 static inline void release_thread(struct task_struct *dead_task)
  70 {
  71 }
  72
  73 /* Free all resources held by a thread. */
  74 static inline void exit_thread(void)
  75 {
  76 }
  77
  78 extern unsigned long thread_saved_pc(struct task_struct *t);
  79
  80 extern unsigned long get_wchan(struct task_struct *p);
  81
  82 # define KSTK_EIP(tsk)  (0)
  83 # define KSTK_ESP(tsk)  (0)
  84
  85 # else /* CONFIG_MMU */
  86
  87 /*
  88  * This is used to define STACK_TOP, and with MMU it must be below
  89  * kernel base to select the correct PGD when handling MMU exceptions.
  90  */
  91 # define TASK_SIZE      (CONFIG_KERNEL_START)
  92
  93 /*
  94  * This decides where the kernel will search for a free chunk of vm
  95  * space during mmap's.
  96  */
  97 # define TASK_UNMAPPED_BASE     (TASK_SIZE / 8 * 3)
  98
  99 # define THREAD_KSP     0
 100
 101 #  ifndef __ASSEMBLY__
 102
 103 /*
 104  * Default implementation of macro that returns current
 105  * instruction pointer ("program counter").
 106  */
 107 #  define current_text_addr()   ({ __label__ _l; _l: &&_l; })
 108
 109 /* If you change this, you must change the associated assembly-languages
 110  * constants defined below, THREAD_*.
 111  */
 112 struct thread_struct {
 113         /* kernel stack pointer (must be first field in structure) */
 114         unsigned long   ksp;
 115         unsigned long   ksp_limit;      /* if ksp <= ksp_limit stack overflow */
 116         void            *pgdir;         /* root of page-table tree */
 117         struct pt_regs  *regs;          /* Pointer to saved register state */
 118 };
 119
 120 #  define INIT_THREAD { \
 121         .ksp   = sizeof init_stack + (unsigned long)init_stack, \
 122         .pgdir = swapper_pg_dir, \
 123 }
 124
 125 /* Free all resources held by a thread. */
 126 static inline void release_thread(struct task_struct *dead_task)
 127 {
 128 }
 129
 130 /* Free current thread data structures etc.  */
 131 static inline void exit_thread(void)
 132 {
 133 }
 134
 135 /* Return saved (kernel) PC of a blocked thread.  */
 136 #  define thread_saved_pc(tsk)  \
 137         ((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0)
 138
 139 unsigned long get_wchan(struct task_struct *p);
 140
 141 /* The size allocated for kernel stacks. This _must_ be a power of two! */
 142 # define KERNEL_STACK_SIZE      0x2000
 143
 144 /* Return some info about the user process TASK.  */
 145 #  define task_tos(task)        ((unsigned long)(task) + KERNEL_STACK_SIZE)
 146 #  define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)
 147
 148 #  define task_pt_regs_plus_args(tsk) \
 149         ((void *)task_pt_regs(tsk))
 150
 151 #  define task_sp(task) (task_regs(task)->r1)
 152 #  define task_pc(task) (task_regs(task)->pc)
 153 /* Grotty old names for some.  */
 154 #  define KSTK_EIP(task)        (task_pc(task))
 155 #  define KSTK_ESP(task)        (task_sp(task))
 156
 157 /* FIXME */
 158 #  define deactivate_mm(tsk, mm)        do { } while (0)
 159
 160 #  define STACK_TOP     TASK_SIZE
 161 #  define STACK_TOP_MAX STACK_TOP
 162
 163 #ifdef CONFIG_DEBUG_FS
 164 extern struct dentry *of_debugfs_root;
 165 #endif
 166
 167 #  endif /* __ASSEMBLY__ */
 168 # endif /* CONFIG_MMU */
 169 #endif /* _ASM_MICROBLAZE_PROCESSOR_H */