include/asm-mips/processor.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 Waldorf GMBH
   7  * Copyright (C) 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2003 Ralf Baechle
   8  * Copyright (C) 1996 Paul M. Antoine
   9  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
  10  */
  11 #ifndef _ASM_PROCESSOR_H
  12 #define _ASM_PROCESSOR_H
  13
  14 #include <linux/config.h>
  15 #include <linux/threads.h>
  16
  17 #include <asm/cachectl.h>
  18 #include <asm/cpu.h>
  19 #include <asm/cpu-info.h>
  20 #include <asm/mipsregs.h>
  21 #include <asm/prefetch.h>
  22 #include <asm/system.h>
  23
  24 /*
  25  * Return current * instruction pointer ("program counter").
  26  */
  27 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
  28
  29 /*
  30  * System setup and hardware flags..
  31  */
  32 extern void (*cpu_wait)(void);
  33
  34 extern unsigned int vced_count, vcei_count;
  35
  36 #ifdef CONFIG_32BIT
  37 /*
  38  * User space process size: 2GB. This is hardcoded into a few places,
  39  * so don't change it unless you know what you are doing.
  40  */
  41 #define TASK_SIZE       0x7fff8000UL
  42
  43 /*
  44  * This decides where the kernel will search for a free chunk of vm
  45  * space during mmap's.
  46  */
  47 #define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 3))
  48 #endif
  49
  50 #ifdef CONFIG_64BIT
  51 /*
  52  * User space process size: 1TB. This is hardcoded into a few places,
  53  * so don't change it unless you know what you are doing.  TASK_SIZE
  54  * is limited to 1TB by the R4000 architecture; R10000 and better can
  55  * support 16TB; the architectural reserve for future expansion is
  56  * 8192EB ...
  57  */
  58 #define TASK_SIZE32     0x7fff8000UL
  59 #define TASK_SIZE       0x10000000000UL
  60
  61 /*
  62  * This decides where the kernel will search for a free chunk of vm
  63  * space during mmap's.
  64  */
  65 #define TASK_UNMAPPED_BASE      ((current->thread.mflags & MF_32BIT_ADDR) ? \
  66         PAGE_ALIGN(TASK_SIZE32 / 3) : PAGE_ALIGN(TASK_SIZE / 3))
  67 #endif
  68
  69 #define NUM_FPU_REGS    32
  70
  71 typedef __u64 fpureg_t;
  72
  73 struct mips_fpu_hard_struct {
  74         fpureg_t        fpr[NUM_FPU_REGS];
  75         unsigned int    fcr31;
  76 };
  77
  78 /*
  79  * It would be nice to add some more fields for emulator statistics, but there
  80  * are a number of fixed offsets in offset.h and elsewhere that would have to
  81  * be recalculated by hand.  So the additional information will be private to
  82  * the FPU emulator for now.  See asm-mips/fpu_emulator.h.
  83  */
  84
  85 struct mips_fpu_soft_struct {
  86         fpureg_t        fpr[NUM_FPU_REGS];
  87         unsigned int    fcr31;
  88 };
  89
  90 union mips_fpu_union {
  91         struct mips_fpu_hard_struct hard;
  92         struct mips_fpu_soft_struct soft;
  93 };
  94
  95 #define INIT_FPU { \
  96         {{0,},} \
  97 }
  98
  99 #define NUM_DSP_REGS   6
 100
 101 typedef __u32 dspreg_t;
 102
 103 struct mips_dsp_state {
 104         dspreg_t        dspr[NUM_DSP_REGS];
 105         unsigned int    dspcontrol;
 106         unsigned short  used_dsp;
 107 };
 108
 109 #define INIT_DSP {{0,},}
 110
 111 typedef struct {
 112         unsigned long seg;
 113 } mm_segment_t;
 114
 115 #define ARCH_MIN_TASKALIGN      8
 116
 117 struct mips_abi;
 118
 119 /*
 120  * If you change thread_struct remember to change the #defines below too!
 121  */
 122 struct thread_struct {
 123         /* Saved main processor registers. */
 124         unsigned long reg16;
 125         unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
 126         unsigned long reg29, reg30, reg31;
 127
 128         /* Saved cp0 stuff. */
 129         unsigned long cp0_status;
 130
 131         /* Saved fpu/fpu emulator stuff. */
 132         union mips_fpu_union fpu;
 133
 134         /* Saved state of the DSP ASE, if available. */
 135         struct mips_dsp_state dsp;
 136
 137         /* Other stuff associated with the thread. */
 138         unsigned long cp0_badvaddr;     /* Last user fault */
 139         unsigned long cp0_baduaddr;     /* Last kernel fault accessing USEG */
 140         unsigned long error_code;
 141         unsigned long trap_no;
 142 #define MF_FIXADE       1               /* Fix address errors in software */
 143 #define MF_LOGADE       2               /* Log address errors to syslog */
 144 #define MF_32BIT_REGS   4               /* also implies 16/32 fprs */
 145 #define MF_32BIT_ADDR   8               /* 32-bit address space (o32/n32) */
 146         unsigned long mflags;
 147         unsigned long irix_trampoline;  /* Wheee... */
 148         unsigned long irix_oldctx;
 149         struct mips_abi *abi;
 150 };
 151
 152 #define MF_ABI_MASK     (MF_32BIT_REGS | MF_32BIT_ADDR)
 153 #define MF_O32          (MF_32BIT_REGS | MF_32BIT_ADDR)
 154 #define MF_N32          MF_32BIT_ADDR
 155 #define MF_N64          0
 156
 157 #define INIT_THREAD  { \
 158         /* \
 159          * saved main processor registers \
 160          */ \
 161         0, 0, 0, 0, 0, 0, 0, 0, \
 162                        0, 0, 0, \
 163         /* \
 164          * saved cp0 stuff \
 165          */ \
 166         0, \
 167         /* \
 168          * saved fpu/fpu emulator stuff \
 169          */ \
 170         INIT_FPU, \
 171         /* \
 172          * saved dsp/dsp emulator stuff \
 173          */ \
 174         INIT_DSP, \
 175         /* \
 176          * Other stuff associated with the process \
 177          */ \
 178         0, 0, 0, 0, \
 179         /* \
 180          * For now the default is to fix address errors \
 181          */ \
 182         MF_FIXADE, 0, 0 \
 183 }
 184
 185 struct task_struct;
 186
 187 /* Free all resources held by a thread. */
 188 #define release_thread(thread) do { } while(0)
 189
 190 /* Prepare to copy thread state - unlazy all lazy status */
 191 #define prepare_to_copy(tsk)    do { } while (0)
 192
 193 extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 194
 195 extern unsigned long thread_saved_pc(struct task_struct *tsk);
 196
 197 /*
 198  * Do necessary setup to start up a newly executed thread.
 199  */
 200 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
 201
 202 unsigned long get_wchan(struct task_struct *p);
 203
 204 #define __PT_REG(reg) ((long)&((struct pt_regs *)0)->reg - sizeof(struct pt_regs))
 205 #define __KSTK_TOS(tsk) ((unsigned long)(tsk->thread_info) + THREAD_SIZE - 32)
 206 #define KSTK_EIP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_epc)))
 207 #define KSTK_ESP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(regs[29])))
 208 #define KSTK_STATUS(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_status)))
 209
 210 #define cpu_relax()     barrier()
 211
 212 /*
 213  * Return_address is a replacement for __builtin_return_address(count)
 214  * which on certain architectures cannot reasonably be implemented in GCC
 215  * (MIPS, Alpha) or is unuseable with -fomit-frame-pointer (i386).
 216  * Note that __builtin_return_address(x>=1) is forbidden because GCC
 217  * aborts compilation on some CPUs.  It's simply not possible to unwind
 218  * some CPU's stackframes.
 219  *
 220  * __builtin_return_address works only for non-leaf functions.  We avoid the
 221  * overhead of a function call by forcing the compiler to save the return
 222  * address register on the stack.
 223  */
 224 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
 225
 226 #ifdef CONFIG_CPU_HAS_PREFETCH
 227
 228 #define ARCH_HAS_PREFETCH
 229
 230 extern inline void prefetch(const void *addr)
 231 {
 232         __asm__ __volatile__(
 233         "       .set    mips4           \n"
 234         "       pref    %0, (%1)        \n"
 235         "       .set    mips0           \n"
 236         :
 237         : "i" (Pref_Load), "r" (addr));
 238 }
 239
 240 #endif
 241
 242 #endif /* _ASM_PROCESSOR_H */