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 #if 0
  91 /* Dummy fpu emulator  */
  92 struct sh_fpu_soft_struct {
  93         unsigned long long fp_regs[32];
  94         unsigned int fpscr;
  95         unsigned char lookahead;
  96         unsigned long entry_pc;
  97 };
  98 #endif
  99
 100 union sh_fpu_union {
 101         struct sh_fpu_hard_struct hard;
 102         /* 'hard' itself only produces 32 bit alignment, yet we need
 103            to access it using 64 bit load/store as well. */
 104         unsigned long long alignment_dummy;
 105 };
 106
 107 struct thread_struct {
 108         unsigned long sp;
 109         unsigned long pc;
 110         /* This stores the address of the pt_regs built during a context
 111            switch, or of the register save area built for a kernel mode
 112            exception.  It is used for backtracing the stack of a sleeping task
 113            or one that traps in kernel mode. */
 114         struct pt_regs *kregs;
 115         /* This stores the address of the pt_regs constructed on entry from
 116            user mode.  It is a fixed value over the lifetime of a process, or
 117            NULL for a kernel thread. */
 118         struct pt_regs *uregs;
 119
 120         unsigned long trap_no, error_code;
 121         unsigned long address;
 122         /* Hardware debugging registers may come here */
 123
 124         /* floating point info */
 125         union sh_fpu_union fpu;
 126 };
 127
 128 #define INIT_MMAP \
 129 { &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL }
 130
 131 #define INIT_THREAD  {                          \
 132         .sp             = sizeof(init_stack) +  \
 133                           (long) &init_stack,   \
 134         .pc             = 0,                    \
 135         .kregs          = &fake_swapper_regs,   \
 136         .uregs          = NULL,                 \
 137         .trap_no        = 0,                    \
 138         .error_code     = 0,                    \
 139         .address        = 0,                    \
 140         .fpu            = { { { 0, } }, }       \
 141 }
 142
 143 /*
 144  * Do necessary setup to start up a newly executed thread.
 145  */
 146 #define SR_USER (SR_MMU | SR_FD)
 147
 148 #define start_thread(_regs, new_pc, new_sp)                     \
 149         set_fs(USER_DS);                                        \
 150         _regs->sr = SR_USER;    /* User mode. */                \
 151         _regs->pc = new_pc - 4; /* Compensate syscall exit */   \
 152         _regs->pc |= 1;         /* Set SHmedia ! */             \
 153         _regs->regs[18] = 0;                                    \
 154         _regs->regs[15] = new_sp
 155
 156 /* Forward declaration, a strange C thing */
 157 struct task_struct;
 158 struct mm_struct;
 159
 160 /* Free all resources held by a thread. */
 161 extern void release_thread(struct task_struct *);
 162 /*
 163  * create a kernel thread without removing it from tasklists
 164  */
 165 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 166
 167
 168 /* Copy and release all segment info associated with a VM */
 169 #define copy_segments(p, mm)    do { } while (0)
 170 #define release_segments(mm)    do { } while (0)
 171 #define forget_segments()       do { } while (0)
 172 #define prepare_to_copy(tsk)    do { } while (0)
 173 /*
 174  * FPU lazy state save handling.
 175  */
 176
 177 static inline void disable_fpu(void)
 178 {
 179         unsigned long long __dummy;
 180
 181         /* Set FD flag in SR */
 182         __asm__ __volatile__("getcon    " __SR ", %0\n\t"
 183                              "or        %0, %1, %0\n\t"
 184                              "putcon    %0, " __SR "\n\t"
 185                              : "=&r" (__dummy)
 186                              : "r" (SR_FD));
 187 }
 188
 189 static inline void enable_fpu(void)
 190 {
 191         unsigned long long __dummy;
 192
 193         /* Clear out FD flag in SR */
 194         __asm__ __volatile__("getcon    " __SR ", %0\n\t"
 195                              "and       %0, %1, %0\n\t"
 196                              "putcon    %0, " __SR "\n\t"
 197                              : "=&r" (__dummy)
 198                              : "r" (~SR_FD));
 199 }
 200
 201 /* Round to nearest, no exceptions on inexact, overflow, underflow,
 202    zero-divide, invalid.  Configure option for whether to flush denorms to
 203    zero, or except if a denorm is encountered.  */
 204 #if defined(CONFIG_SH64_FPU_DENORM_FLUSH)
 205 #define FPSCR_INIT  0x00040000
 206 #else
 207 #define FPSCR_INIT  0x00000000
 208 #endif
 209
 210 #ifdef CONFIG_SH_FPU
 211 /* Initialise the FP state of a task */
 212 void fpinit(struct sh_fpu_hard_struct *fpregs);
 213 #else
 214 #define fpinit(fpregs)  do { } while (0)
 215 #endif
 216
 217 extern struct task_struct *last_task_used_math;
 218
 219 /*
 220  * Return saved PC of a blocked thread.
 221  */
 222 #define thread_saved_pc(tsk)    (tsk->thread.pc)
 223
 224 extern unsigned long get_wchan(struct task_struct *p);
 225
 226 #define KSTK_EIP(tsk)  ((tsk)->thread.pc)
 227 #define KSTK_ESP(tsk)  ((tsk)->thread.sp)
 228
 229 #define user_stack_pointer(_regs)       ((_regs)->regs[15])
 230
 231 #endif  /* __ASSEMBLY__ */
 232 #endif /* __ASM_SH_PROCESSOR_64_H */