release/src-rt-6.x.4708/linux/linux-2.6.36/arch/sh/include/asm/processor_64.h

   1 #ifndef __ASM_SH_PROCESSOR_64_H
   2 #define __ASM_SH_PROCESSOR_64_H
   3
   4 /*
   5  * include/asm-sh/processor_64.h
   6  *
   7  * Copyright (C) 2000, 2001  Paolo Alberelli
   8  * Copyright (C) 2003  Paul Mundt
   9  * Copyright (C) 2004  Richard Curnow
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  */
  15 #ifndef __ASSEMBLY__
  16
  17 #include <linux/compiler.h>
  18 #include <asm/page.h>
  19 #include <asm/types.h>
  20 #include <asm/ptrace.h>
  21 #include <cpu/registers.h>
  22
  23 /*
  24  * Default implementation of macro that returns current
  25  * instruction pointer ("program counter").
  26  */
  27 #define current_text_addr() ({ \
  28 void *pc; \
  29 unsigned long long __dummy = 0; \
  30 __asm__("gettr  tr0, %1\n\t" \
  31         "pta    4, tr0\n\t" \
  32         "gettr  tr0, %0\n\t" \
  33         "ptabs  %1, tr0\n\t"    \
  34         :"=r" (pc), "=r" (__dummy) \
  35         : "1" (__dummy)); \
  36 pc; })
  37
  38 #endif
  39
  40 /*
  41  * User space process size: 2GB - 4k.
  42  */
  43 #define TASK_SIZE       0x7ffff000UL
  44
  45 #define STACK_TOP       TASK_SIZE
  46 #define STACK_TOP_MAX   STACK_TOP
  47
  48 /* This decides where the kernel will search for a free chunk of vm
  49  * space during mmap's.
  50  */
  51 #define TASK_UNMAPPED_BASE      (TASK_SIZE / 3)
  52
  53 /*
  54  * Bit of SR register
  55  *
  56  * FD-bit:
  57  *     When it's set, it means the processor doesn't have right to use FPU,
  58  *     and it results exception when the floating operation is executed.
  59  *
  60  * IMASK-bit:
  61  *     Interrupt level mask
  62  *
  63  * STEP-bit:
  64  *     Single step bit
  65  *
  66  */
  67 #if defined(CONFIG_SH64_SR_WATCH)
  68 #define SR_MMU   0x84000000
  69 #else
  70 #define SR_MMU   0x80000000
  71 #endif
  72
  73 #define SR_IMASK 0x000000f0
  74 #define SR_FD    0x00008000
  75 #define SR_SSTEP 0x08000000
  76
  77 #ifndef __ASSEMBLY__
  78
  79 /*
  80  * FPU structure and data : require 8-byte alignment as we need to access it
  81    with fld.p, fst.p
  82  */
  83
  84 struct sh_fpu_hard_struct {
  85         unsigned long fp_regs[64];
  86         unsigned int fpscr;
  87         /* long status; * software status information */
  88 };
  89
  90 /* Dummy fpu emulator  */
  91 struct sh_fpu_soft_struct {
  92         unsigned long fp_regs[64];
  93         unsigned int fpscr;
  94         unsigned char lookahead;
  95         unsigned long entry_pc;
  96 };
  97
  98 union thread_xstate {
  99         struct sh_fpu_hard_struct hardfpu;
 100         struct sh_fpu_soft_struct softfpu;
 101         /*
 102          * The structure definitions only produce 32 bit alignment, yet we need
 103          * to access them using 64 bit load/store as well.
 104          */
 105         unsigned long long alignment_dummy;
 106 };
 107
 108 struct thread_struct {
 109         unsigned long sp;
 110         unsigned long pc;
 111
 112         /* Various thread flags, see SH_THREAD_xxx */
 113         unsigned long flags;
 114
 115         /* This stores the address of the pt_regs built during a context
 116            switch, or of the register save area built for a kernel mode
 117            exception.  It is used for backtracing the stack of a sleeping task
 118            or one that traps in kernel mode. */
 119         struct pt_regs *kregs;
 120         /* This stores the address of the pt_regs constructed on entry from
 121            user mode.  It is a fixed value over the lifetime of a process, or
 122            NULL for a kernel thread. */
 123         struct pt_regs *uregs;
 124
 125         unsigned long trap_no, error_code;
 126         unsigned long address;
 127         /* Hardware debugging registers may come here */
 128
 129         /* floating point info */
 130         union thread_xstate *xstate;
 131 };
 132
 133 #define INIT_MMAP \
 134 { &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL }
 135
 136 #define INIT_THREAD  {                          \
 137         .sp             = sizeof(init_stack) +  \
 138                           (long) &init_stack,   \
 139         .pc             = 0,                    \
 140         .kregs          = &fake_swapper_regs,   \
 141         .uregs          = NULL,                 \
 142         .trap_no        = 0,                    \
 143         .error_code     = 0,                    \
 144         .address        = 0,                    \
 145         .flags          = 0,                    \
 146 }
 147
 148 /*
 149  * Do necessary setup to start up a newly executed thread.
 150  */
 151 #define SR_USER (SR_MMU | SR_FD)
 152
 153 #define start_thread(_regs, new_pc, new_sp)                     \
 154         set_fs(USER_DS);                                        \
 155         _regs->sr = SR_USER;    /* User mode. */                \
 156         _regs->pc = new_pc - 4; /* Compensate syscall exit */   \
 157         _regs->pc |= 1;         /* Set SHmedia ! */             \
 158         _regs->regs[18] = 0;                                    \
 159         _regs->regs[15] = new_sp
 160
 161 /* Forward declaration, a strange C thing */
 162 struct task_struct;
 163 struct mm_struct;
 164
 165 /* Free all resources held by a thread. */
 166 extern void release_thread(struct task_struct *);
 167 /*
 168  * create a kernel thread without removing it from tasklists
 169  */
 170 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 171
 172
 173 /* Copy and release all segment info associated with a VM */
 174 #define copy_segments(p, mm)    do { } while (0)
 175 #define release_segments(mm)    do { } while (0)
 176 #define forget_segments()       do { } while (0)
 177 #define prepare_to_copy(tsk)    do { } while (0)
 178 /*
 179  * FPU lazy state save handling.
 180  */
 181
 182 static inline void disable_fpu(void)
 183 {
 184         unsigned long long __dummy;
 185
 186         /* Set FD flag in SR */
 187         __asm__ __volatile__("getcon    " __SR ", %0\n\t"
 188                              "or        %0, %1, %0\n\t"
 189                              "putcon    %0, " __SR "\n\t"
 190                              : "=&r" (__dummy)
 191                              : "r" (SR_FD));
 192 }
 193
 194 static inline void enable_fpu(void)
 195 {
 196         unsigned long long __dummy;
 197
 198         /* Clear out FD flag in SR */
 199         __asm__ __volatile__("getcon    " __SR ", %0\n\t"
 200                              "and       %0, %1, %0\n\t"
 201                              "putcon    %0, " __SR "\n\t"
 202                              : "=&r" (__dummy)
 203                              : "r" (~SR_FD));
 204 }
 205
 206 /* Round to nearest, no exceptions on inexact, overflow, underflow,
 207    zero-divide, invalid.  Configure option for whether to flush denorms to
 208    zero, or except if a denorm is encountered.  */
 209 #if defined(CONFIG_SH64_FPU_DENORM_FLUSH)
 210 #define FPSCR_INIT  0x00040000
 211 #else
 212 #define FPSCR_INIT  0x00000000
 213 #endif
 214
 215 #ifdef CONFIG_SH_FPU
 216 /* Initialise the FP state of a task */
 217 void fpinit(struct sh_fpu_hard_struct *fpregs);
 218 #else
 219 #define fpinit(fpregs)  do { } while (0)
 220 #endif
 221
 222 extern struct task_struct *last_task_used_math;
 223
 224 /*
 225  * Return saved PC of a blocked thread.
 226  */
 227 #define thread_saved_pc(tsk)    (tsk->thread.pc)
 228
 229 extern unsigned long get_wchan(struct task_struct *p);
 230
 231 #define KSTK_EIP(tsk)  ((tsk)->thread.pc)
 232 #define KSTK_ESP(tsk)  ((tsk)->thread.sp)
 233
 234 #define user_stack_pointer(_regs)       ((_regs)->regs[15])
 235
 236 #endif  /* __ASSEMBLY__ */
 237 #endif /* __ASM_SH_PROCESSOR_64_H */