arch/mn10300/include/asm/processor.h

   1 /* MN10300 Processor specifics
   2  *
   3  * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
   4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   5  * Written by David Howells (dhowells@redhat.com)
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public Licence
   9  * as published by the Free Software Foundation; either version
  10  * 2 of the Licence, or (at your option) any later version.
  11  */
  12
  13 #ifndef _ASM_PROCESSOR_H
  14 #define _ASM_PROCESSOR_H
  15
  16 #include <linux/threads.h>
  17 #include <linux/thread_info.h>
  18 #include <asm/page.h>
  19 #include <asm/ptrace.h>
  20 #include <asm/cpu-regs.h>
  21 #include <asm/uaccess.h>
  22 #include <asm/current.h>
  23
  24 /* Forward declaration, a strange C thing */
  25 struct task_struct;
  26 struct mm_struct;
  27
  28 /*
  29  * Default implementation of macro that returns current
  30  * instruction pointer ("program counter").
  31  */
  32 #define current_text_addr()                     \
  33 ({                                              \
  34         void *__pc;                             \
  35         asm("mov pc,%0" : "=a"(__pc));          \
  36         __pc;                                   \
  37 })
  38
  39 extern void get_mem_info(unsigned long *mem_base, unsigned long *mem_size);
  40
  41 extern void show_registers(struct pt_regs *regs);
  42
  43 /*
  44  *  CPU type and hardware bug flags. Kept separately for each CPU.
  45  *  Members of this structure are referenced in head.S, so think twice
  46  *  before touching them. [mj]
  47  */
  48
  49 struct mn10300_cpuinfo {
  50         int             type;
  51         unsigned long   loops_per_jiffy;
  52         char            hard_math;
  53 };
  54
  55 extern struct mn10300_cpuinfo boot_cpu_data;
  56
  57 #ifdef CONFIG_SMP
  58 #if CONFIG_NR_CPUS < 2 || CONFIG_NR_CPUS > 8
  59 # error Sorry, NR_CPUS should be 2 to 8
  60 #endif
  61 extern struct mn10300_cpuinfo cpu_data[];
  62 #define current_cpu_data cpu_data[smp_processor_id()]
  63 #else  /* CONFIG_SMP */
  64 #define cpu_data &boot_cpu_data
  65 #define current_cpu_data boot_cpu_data
  66 #endif /* CONFIG_SMP */
  67
  68 extern void identify_cpu(struct mn10300_cpuinfo *);
  69 extern void print_cpu_info(struct mn10300_cpuinfo *);
  70 extern void dodgy_tsc(void);
  71 #define cpu_relax() barrier()
  72
  73 /*
  74  * User space process size: 1.75GB (default).
  75  */
  76 #define TASK_SIZE               0x70000000
  77
  78 /*
  79  * Where to put the userspace stack by default
  80  */
  81 #define STACK_TOP               0x70000000
  82 #define STACK_TOP_MAX           STACK_TOP
  83
  84 /* This decides where the kernel will search for a free chunk of vm
  85  * space during mmap's.
  86  */
  87 #define TASK_UNMAPPED_BASE      0x30000000
  88
  89 struct fpu_state_struct {
  90         unsigned long   fs[32];         /* fpu registers */
  91         unsigned long   fpcr;           /* fpu control register */
  92 };
  93
  94 struct thread_struct {
  95         struct pt_regs          *uregs;         /* userspace register frame */
  96         unsigned long           pc;             /* kernel PC */
  97         unsigned long           sp;             /* kernel SP */
  98         unsigned long           a3;             /* kernel FP */
  99         unsigned long           wchan;
 100         unsigned long           usp;
 101         unsigned long           fpu_flags;
 102 #define THREAD_USING_FPU        0x00000001      /* T if this task is using the FPU */
 103 #define THREAD_HAS_FPU          0x00000002      /* T if this task owns the FPU right now */
 104         struct fpu_state_struct fpu_state;
 105 };
 106
 107 #define INIT_THREAD             \
 108 {                               \
 109         .uregs  = init_uregs,   \
 110         .pc     = 0,            \
 111         .sp     = 0,            \
 112         .a3     = 0,            \
 113         .wchan  = 0,            \
 114 }
 115
 116 #define INIT_MMAP \
 117 { &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, \
 118   NULL, NULL }
 119
 120 /*
 121  * do necessary setup to start up a newly executed thread
 122  * - need to discard the frame stacked by the kernel thread invoking the execve
 123  *   syscall (see RESTORE_ALL macro)
 124  */
 125 static inline void start_thread(struct pt_regs *regs,
 126                                 unsigned long new_pc, unsigned long new_sp)
 127 {
 128         struct thread_info *ti = current_thread_info();
 129         struct pt_regs *frame0;
 130
 131         frame0 = thread_info_to_uregs(ti);
 132         frame0->epsw = EPSW_nSL | EPSW_IE | EPSW_IM;
 133         frame0->pc = new_pc;
 134         frame0->sp = new_sp;
 135         ti->frame = frame0;
 136 }
 137
 138
 139 /* Free all resources held by a thread. */
 140 extern void release_thread(struct task_struct *);
 141
 142 /* Prepare to copy thread state - unlazy all lazy status */
 143 extern void prepare_to_copy(struct task_struct *tsk);
 144
 145 /*
 146  * create a kernel thread without removing it from tasklists
 147  */
 148 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 149
 150 /*
 151  * Return saved PC of a blocked thread.
 152  */
 153 extern unsigned long thread_saved_pc(struct task_struct *tsk);
 154
 155 unsigned long get_wchan(struct task_struct *p);
 156
 157 #define task_pt_regs(task) ((task)->thread.uregs)
 158 #define KSTK_EIP(task) (task_pt_regs(task)->pc)
 159 #define KSTK_ESP(task) (task_pt_regs(task)->sp)
 160
 161 #define KSTK_TOP(info)                          \
 162 ({                                              \
 163         (unsigned long)(info) + THREAD_SIZE;    \
 164 })
 165
 166 #define ARCH_HAS_PREFETCH
 167 #define ARCH_HAS_PREFETCHW
 168
 169 static inline void prefetch(const void *x)
 170 {
 171 #ifdef CONFIG_MN10300_CACHE_ENABLED
 172 #ifdef CONFIG_MN10300_PROC_MN103E010
 173         asm volatile ("nop; nop; dcpf (%0)" : : "r"(x));
 174 #else
 175         asm volatile ("dcpf (%0)" : : "r"(x));
 176 #endif
 177 #endif
 178 }
 179
 180 static inline void prefetchw(const void *x)
 181 {
 182 #ifdef CONFIG_MN10300_CACHE_ENABLED
 183 #ifdef CONFIG_MN10300_PROC_MN103E010
 184         asm volatile ("nop; nop; dcpf (%0)" : : "r"(x));
 185 #else
 186         asm volatile ("dcpf (%0)" : : "r"(x));
 187 #endif
 188 #endif
 189 }
 190
 191 #endif /* _ASM_PROCESSOR_H */