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 typedef struct {
 100         unsigned long seg;
 101 } mm_segment_t;
 102
 103 #define ARCH_MIN_TASKALIGN      8
 104
 105 /*
 106  * If you change thread_struct remember to change the #defines below too!
 107  */
 108 struct thread_struct {
 109         /* Saved main processor registers. */
 110         unsigned long reg16;
 111         unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
 112         unsigned long reg29, reg30, reg31;
 113
 114         /* Saved cp0 stuff. */
 115         unsigned long cp0_status;
 116
 117         /* Saved fpu/fpu emulator stuff. */
 118         union mips_fpu_union fpu;
 119
 120         /* Other stuff associated with the thread. */
 121         unsigned long cp0_badvaddr;     /* Last user fault */
 122         unsigned long cp0_baduaddr;     /* Last kernel fault accessing USEG */
 123         unsigned long error_code;
 124         unsigned long trap_no;
 125 #define MF_FIXADE       1               /* Fix address errors in software */
 126 #define MF_LOGADE       2               /* Log address errors to syslog */
 127 #define MF_32BIT_REGS   4               /* also implies 16/32 fprs */
 128 #define MF_32BIT_ADDR   8               /* 32-bit address space (o32/n32) */
 129         unsigned long mflags;
 130         unsigned long irix_trampoline;  /* Wheee... */
 131         unsigned long irix_oldctx;
 132 };
 133
 134 #define MF_ABI_MASK     (MF_32BIT_REGS | MF_32BIT_ADDR)
 135 #define MF_O32          (MF_32BIT_REGS | MF_32BIT_ADDR)
 136 #define MF_N32          MF_32BIT_ADDR
 137 #define MF_N64          0
 138
 139 #define INIT_THREAD  { \
 140         /* \
 141          * saved main processor registers \
 142          */ \
 143         0, 0, 0, 0, 0, 0, 0, 0, \
 144                        0, 0, 0, \
 145         /* \
 146          * saved cp0 stuff \
 147          */ \
 148         0, \
 149         /* \
 150          * saved fpu/fpu emulator stuff \
 151          */ \
 152         INIT_FPU, \
 153         /* \
 154          * Other stuff associated with the process \
 155          */ \
 156         0, 0, 0, 0, \
 157         /* \
 158          * For now the default is to fix address errors \
 159          */ \
 160         MF_FIXADE, 0, 0 \
 161 }
 162
 163 struct task_struct;
 164
 165 /* Free all resources held by a thread. */
 166 #define release_thread(thread) do { } while(0)
 167
 168 /* Prepare to copy thread state - unlazy all lazy status */
 169 #define prepare_to_copy(tsk)    do { } while (0)
 170
 171 extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 172
 173 extern unsigned long thread_saved_pc(struct task_struct *tsk);
 174
 175 /*
 176  * Do necessary setup to start up a newly executed thread.
 177  */
 178 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
 179
 180 unsigned long get_wchan(struct task_struct *p);
 181
 182 #define __PT_REG(reg) ((long)&((struct pt_regs *)0)->reg - sizeof(struct pt_regs))
 183 #define __KSTK_TOS(tsk) ((unsigned long)(tsk->thread_info) + THREAD_SIZE - 32)
 184 #define KSTK_EIP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_epc)))
 185 #define KSTK_ESP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(regs[29])))
 186 #define KSTK_STATUS(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_status)))
 187
 188 #define cpu_relax()     barrier()
 189
 190 /*
 191  * Return_address is a replacement for __builtin_return_address(count)
 192  * which on certain architectures cannot reasonably be implemented in GCC
 193  * (MIPS, Alpha) or is unuseable with -fomit-frame-pointer (i386).
 194  * Note that __builtin_return_address(x>=1) is forbidden because GCC
 195  * aborts compilation on some CPUs.  It's simply not possible to unwind
 196  * some CPU's stackframes.
 197  *
 198  * __builtin_return_address works only for non-leaf functions.  We avoid the
 199  * overhead of a function call by forcing the compiler to save the return
 200  * address register on the stack.
 201  */
 202 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
 203
 204 #ifdef CONFIG_CPU_HAS_PREFETCH
 205
 206 #define ARCH_HAS_PREFETCH
 207
 208 extern inline void prefetch(const void *addr)
 209 {
 210         __asm__ __volatile__(
 211         "       .set    mips4           \n"
 212         "       pref    %0, (%1)        \n"
 213         "       .set    mips0           \n"
 214         :
 215         : "i" (Pref_Load), "r" (addr));
 216 }
 217
 218 #endif
 219
 220 #endif /* _ASM_PROCESSOR_H */