include/asm-m68k/entry.h

   1 #ifndef __M68K_ENTRY_H
   2 #define __M68K_ENTRY_H
   3
   4 #include <linux/config.h>
   5 #include <asm/setup.h>
   6 #include <asm/page.h>
   7
   8 /*
   9  * Stack layout in 'ret_from_exception':
  10  *
  11  *      This allows access to the syscall arguments in registers d1-d5
  12  *
  13  *       0(sp) - d1
  14  *       4(sp) - d2
  15  *       8(sp) - d3
  16  *       C(sp) - d4
  17  *      10(sp) - d5
  18  *      14(sp) - a0
  19  *      18(sp) - a1
  20  *      1C(sp) - a2
  21  *      20(sp) - d0
  22  *      24(sp) - orig_d0
  23  *      28(sp) - stack adjustment
  24  *      2C(sp) - sr
  25  *      2E(sp) - pc
  26  *      32(sp) - format & vector
  27  */
  28
  29 /*
  30  * 97/05/14 Andreas: Register %a2 is now set to the current task throughout
  31  *                   the whole kernel.
  32  */
  33
  34 /* the following macro is used when enabling interrupts */
  35 #if defined(MACH_ATARI_ONLY) && !defined(CONFIG_HADES)
  36         /* block out HSYNC on the atari */
  37 #define ALLOWINT        (~0x400)
  38 #define MAX_NOINT_IPL   3
  39 #else
  40         /* portable version */
  41 #define ALLOWINT        (~0x700)
  42 #define MAX_NOINT_IPL   0
  43 #endif /* machine compilation types */
  44
  45 #ifdef __ASSEMBLY__
  46
  47 #define curptr a2
  48
  49 LFLUSH_I_AND_D = 0x00000808
  50 LSIGTRAP = 5
  51
  52 /* process bits for task_struct.ptrace */
  53 PT_TRACESYS_OFF = 3
  54 PT_TRACESYS_BIT = 1
  55 PT_PTRACED_OFF = 3
  56 PT_PTRACED_BIT = 0
  57 PT_DTRACE_OFF = 3
  58 PT_DTRACE_BIT = 2
  59
  60 #define SAVE_ALL_INT save_all_int
  61 #define SAVE_ALL_SYS save_all_sys
  62 #define RESTORE_ALL restore_all
  63 /*
  64  * This defines the normal kernel pt-regs layout.
  65  *
  66  * regs a3-a6 and d6-d7 are preserved by C code
  67  * the kernel doesn't mess with usp unless it needs to
  68  */
  69
  70 /*
  71  * a -1 in the orig_d0 field signifies
  72  * that the stack frame is NOT for syscall
  73  */
  74 .macro  save_all_int
  75         clrl    %sp@-           | stk_adj
  76         pea     -1:w            | orig d0
  77         movel   %d0,%sp@-       | d0
  78         moveml  %d1-%d5/%a0-%a1/%curptr,%sp@-
  79 .endm
  80
  81 .macro  save_all_sys
  82         clrl    %sp@-           | stk_adj
  83         movel   %d0,%sp@-       | orig d0
  84         movel   %d0,%sp@-       | d0
  85         moveml  %d1-%d5/%a0-%a1/%curptr,%sp@-
  86 .endm
  87
  88 .macro  restore_all
  89         moveml  %sp@+,%a0-%a1/%curptr/%d1-%d5
  90         movel   %sp@+,%d0
  91         addql   #4,%sp          | orig d0
  92         addl    %sp@+,%sp       | stk adj
  93         rte
  94 .endm
  95
  96 #define SWITCH_STACK_SIZE (6*4+4)       /* includes return address */
  97
  98 #define SAVE_SWITCH_STACK save_switch_stack
  99 #define RESTORE_SWITCH_STACK restore_switch_stack
 100 #define GET_CURRENT(tmp) get_current tmp
 101
 102 .macro  save_switch_stack
 103         moveml  %a3-%a6/%d6-%d7,%sp@-
 104 .endm
 105
 106 .macro  restore_switch_stack
 107         moveml  %sp@+,%a3-%a6/%d6-%d7
 108 .endm
 109
 110 .macro  get_current reg=%d0
 111         movel   %sp,\reg
 112         andw    #-THREAD_SIZE,\reg
 113         movel   \reg,%curptr
 114         movel   %curptr@,%curptr
 115 .endm
 116
 117 #else /* C source */
 118
 119 #define STR(X) STR1(X)
 120 #define STR1(X) #X
 121
 122 #define PT_OFF_ORIG_D0   0x24
 123 #define PT_OFF_FORMATVEC 0x32
 124 #define PT_OFF_SR        0x2C
 125 #define SAVE_ALL_INT                            \
 126         "clrl   %%sp@-;"    /* stk_adj */       \
 127         "pea    -1:w;"      /* orig d0 = -1 */  \
 128         "movel  %%d0,%%sp@-;" /* d0 */          \
 129         "moveml %%d1-%%d5/%%a0-%%a2,%%sp@-"
 130 #define GET_CURRENT(tmp) \
 131         "movel  %%sp,"#tmp"\n\t" \
 132         "andw   #-"STR(THREAD_SIZE)","#tmp"\n\t" \
 133         "movel  "#tmp",%%a2\n\t" \
 134         "movel  %%a2@,%%a2"
 135
 136 #endif
 137
 138 #endif /* __M68K_ENTRY_H */