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