arch/m68k/include/asm/entry_mm.h

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