include/asm-sh/processor.h

   1 /*
   2  * include/asm-sh/processor.h
   3  *
   4  * Copyright (C) 1999, 2000  Niibe Yutaka
   5  */
   6
   7 #ifndef __ASM_SH_PROCESSOR_H
   8 #define __ASM_SH_PROCESSOR_H
   9
  10 #include <asm/page.h>
  11 #include <asm/types.h>
  12 #include <linux/threads.h>
  13
  14 /*
  15  * Default implementation of macro that returns current
  16  * instruction pointer ("program counter").
  17  */
  18 #define current_text_addr() ({ void *pc; __asm__("mova  1f, %0\n1:":"=z" (pc)); pc; })
  19
  20 /*
  21  *  CPU type and hardware bug flags. Kept separately for each CPU.
  22  */
  23 enum cpu_type {
  24         CPU_SH7708,             /* Represents 7707, 7708, 7708S, 7708R, 7709 */
  25         CPU_SH7729,             /* Represents 7709A, 7729 */
  26         CPU_SH7750,
  27         CPU_SH_NONE
  28 };
  29
  30 struct sh_cpuinfo {
  31         enum cpu_type type;
  32         unsigned long loops_per_sec;
  33
  34         char    hard_math;
  35
  36         unsigned long *pgd_quick;
  37         unsigned long *pte_quick;
  38         unsigned long pgtable_cache_sz;
  39         unsigned int cpu_clock, master_clock, bus_clock, module_clock;
  40 };
  41
  42 extern struct sh_cpuinfo boot_cpu_data;
  43
  44 #define cpu_data (&boot_cpu_data)
  45 #define current_cpu_data boot_cpu_data
  46
  47 /*
  48  * User space process size: 2GB.
  49  *
  50  * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
  51  */
  52 #define TASK_SIZE       0x7c000000UL
  53
  54 /* This decides where the kernel will search for a free chunk of vm
  55  * space during mmap's.
  56  */
  57 #define TASK_UNMAPPED_BASE      (TASK_SIZE / 3)
  58
  59 /*
  60  * Bit of SR register
  61  *
  62  * FD-bit:
  63  *     When it's set, it means the processor doesn't have right to use FPU,
  64  *     and it results exception when the floating operation is executed.
  65  *
  66  * IMASK-bit:
  67  *     Interrupt level mask
  68  */
  69 #define SR_FD    0x00008000
  70 #define SR_IMASK 0x000000f0
  71
  72 /*
  73  * FPU structure and data
  74  */
  75
  76 struct sh_fpu_hard_struct {
  77         unsigned long fp_regs[16];
  78         unsigned long long xd_regs[8];
  79         unsigned long fpscr;
  80         unsigned long fpul;
  81
  82         long status; /* software status information */
  83 };
  84
  85 /* Dummy fpu emulator  */
  86 struct sh_fpu_soft_struct {
  87         unsigned long fp_regs[16];
  88         unsigned long long xd_regs[8];
  89         unsigned long fpscr;
  90         unsigned long fpul;
  91
  92         unsigned char lookahead;
  93         unsigned long entry_pc;
  94 };
  95
  96 union sh_fpu_union {
  97         struct sh_fpu_hard_struct hard;
  98         struct sh_fpu_soft_struct soft;
  99 };
 100
 101 struct thread_struct {
 102         unsigned long sp;
 103         unsigned long pc;
 104
 105         unsigned long trap_no, error_code;
 106         unsigned long address;
 107         /* Hardware debugging registers may come here */
 108
 109         /* floating point info */
 110         union sh_fpu_union fpu;
 111 };
 112
 113 #define INIT_MMAP \
 114 { &init_mm, 0x80000000, 0xa0000000, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL }
 115
 116 #define INIT_THREAD  {                                          \
 117         sizeof(init_stack) + (long) &init_stack, /* sp */       \
 118         0,                                       /* pc */       \
 119         0, 0,                                                   \
 120         0,                                                      \
 121         {{{0,}},}                               /* fpu state */ \
 122 }
 123
 124 /*
 125  * Do necessary setup to start up a newly executed thread.
 126  */
 127 #define start_thread(regs, new_pc, new_sp)       \
 128         set_fs(USER_DS);                         \
 129         regs->pr = 0;                            \
 130         regs->sr = 0;           /* User mode. */ \
 131         regs->pc = new_pc;                       \
 132         regs->regs[15] = new_sp
 133
 134 /* Forward declaration, a strange C thing */
 135 struct task_struct;
 136 struct mm_struct;
 137
 138 /* Free all resources held by a thread. */
 139 extern void release_thread(struct task_struct *);
 140 /*
 141  * create a kernel thread without removing it from tasklists
 142  */
 143 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 144
 145 /*
 146  * Bus types
 147  */
 148 #define EISA_bus 0
 149 #define EISA_bus__is_a_macro /* for versions in ksyms.c */
 150 #define MCA_bus 0
 151 #define MCA_bus__is_a_macro /* for versions in ksyms.c */
 152
 153
 154 /*
 155  * FPU lazy state save handling.
 156  */
 157
 158 extern __inline__ void release_fpu(void)
 159 {
 160         unsigned long __dummy;
 161
 162         /* Set FD flag in SR */
 163         __asm__ __volatile__("stc       $sr, %0\n\t"
 164                              "or        %1, %0\n\t"
 165                              "ldc       %0, $sr"
 166                              : "=&r" (__dummy)
 167                              : "r" (SR_FD));
 168 }
 169
 170 extern __inline__ void grab_fpu(void)
 171 {
 172         unsigned long __dummy;
 173
 174         /* Clear out FD flag in SR */
 175         __asm__ __volatile__("stc       $sr, %0\n\t"
 176                              "and       %1, %0\n\t"
 177                              "ldc       %0, $sr"
 178                              : "=&r" (__dummy)
 179                              : "r" (~SR_FD));
 180 }
 181
 182 extern void save_fpu(struct task_struct *__tsk);
 183
 184 #define unlazy_fpu(tsk) do {                    \
 185         if ((tsk)->flags & PF_USEDFPU) {        \
 186                 grab_fpu();                     \
 187                 save_fpu(tsk);                  \
 188         }                                       \
 189 } while (0)
 190
 191 #define clear_fpu(tsk) do {                     \
 192         if ((tsk)->flags & PF_USEDFPU)          \
 193                 (tsk)->flags &= ~PF_USEDFPU;    \
 194 } while (0)
 195
 196 /* Double presision, NANS as NANS, rounding to nearest, no exceptions */
 197 #define FPSCR_INIT  0x00080000
 198
 199 /*
 200  * Return saved PC of a blocked thread.
 201  */
 202 extern __inline__ unsigned long thread_saved_pc(struct thread_struct *t)
 203 {
 204         return t->pc;
 205 }
 206
 207 extern unsigned long get_wchan(struct task_struct *p);
 208
 209 #define KSTK_EIP(tsk)  ((tsk)->thread.pc)
 210 #define KSTK_ESP(tsk)  ((tsk)->thread.sp)
 211
 212 #define THREAD_SIZE (2*PAGE_SIZE)
 213 extern struct task_struct * alloc_task_struct(void);
 214 extern void free_task_struct(struct task_struct *);
 215 #define get_task_struct(tsk)      atomic_inc(&virt_to_page(tsk)->count)
 216
 217 #define init_task       (init_task_union.task)
 218 #define init_stack      (init_task_union.stack)
 219
 220 #endif /* __ASM_SH_PROCESSOR_H */