target/linux/coldfire/files-2.6.31/arch/m68k/include/asm/cf_entry.h

   1 #ifndef __CF_M68K_ENTRY_H
   2 #define __CF_M68K_ENTRY_H
   3
   4 #include <asm/setup.h>
   5 #include <asm/page.h>
   6 #include <asm/coldfire.h>
   7 #include <asm/cfmmu.h>
   8 #include <asm/asm-offsets.h>
   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  *      36(sp) - MMUSR
  30  *      3A(sp) - MMUAR
  31  */
  32
  33 /*
  34  * 97/05/14 Andreas: Register %a2 is now set to the current task throughout
  35  *                   the whole kernel.
  36  */
  37
  38 /* the following macro is used when enabling interrupts */
  39 /* portable version */
  40 #define ALLOWINT        (~0x700)
  41 #define MAX_NOINT_IPL   0
  42
  43 #ifdef __ASSEMBLY__
  44
  45 #define curptr a2
  46
  47 LFLUSH_I_AND_D = 0x00000808
  48 LSIGTRAP = 5
  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         movel   MMUSR,%sp@-
  74         movel   MMUAR,%sp@-
  75         clrl    %sp@-           | stk_adj
  76         pea     -1:w            | orig d0
  77         movel   %d0,%sp@-       | d0
  78         subal   #(8*4), %sp
  79         moveml  %d1-%d5/%a0-%a1/%curptr,%sp@
  80 .endm
  81
  82 .macro  save_all_sys
  83         movel   MMUSR,%sp@-
  84         movel   MMUAR,%sp@-
  85         clrl    %sp@-           | stk_adj
  86         movel   %d0,%sp@-       | orig d0
  87         movel   %d0,%sp@-       | d0
  88         subal   #(8*4), %sp
  89         moveml  %d1-%d5/%a0-%a1/%curptr,%sp@
  90 .endm
  91
  92 .macro  restore_all
  93         moveml  %sp@,%a0-%a1/%curptr/%d1-%d5
  94         addal   #(8*4), %sp
  95         movel   %sp@+,%d0       | d0
  96         addql   #4,%sp          | orig d0
  97         addl    %sp@+,%sp       | stk_adj
  98         addql   #8,%sp          | MMUAR & MMUSR
  99         rte
 100 .endm
 101
 102 #define SWITCH_STACK_SIZE (6*4+4)       /* includes return address */
 103
 104 #define SAVE_SWITCH_STACK save_switch_stack
 105 #define RESTORE_SWITCH_STACK restore_switch_stack
 106 #define GET_CURRENT(tmp) get_current tmp
 107
 108 .macro  save_switch_stack
 109         subal   #(6*4), %sp
 110         moveml  %a3-%a6/%d6-%d7,%sp@
 111 .endm
 112
 113 .macro  restore_switch_stack
 114         moveml  %sp@,%a3-%a6/%d6-%d7
 115         addal   #(6*4), %sp
 116 .endm
 117
 118 .macro  get_current reg=%d0
 119         movel   %sp,\reg
 120         andl    #-THREAD_SIZE,\reg
 121         movel   \reg,%curptr
 122         movel   %curptr@,%curptr
 123 .endm
 124
 125 #else /* C source */
 126
 127 #define STR(X) STR1(X)
 128 #define STR1(X) #X
 129
 130 #define PT_OFF_ORIG_D0   0x24
 131 #define PT_OFF_FORMATVEC 0x32
 132 #define PT_OFF_SR        0x2C
 133 #define SAVE_ALL_INT                            \
 134         "clrl   %%sp@-;"    /* stk_adj */       \
 135         "pea    -1:w;"      /* orig d0 = -1 */  \
 136         "movel  %%d0,%%sp@-;" /* d0 */          \
 137         "subal  #(8*4),%sp"                     \
 138         "moveml %%d1-%%d5/%%a0-%%a2,%%sp@"
 139 #define GET_CURRENT(tmp) \
 140         "movel  %%sp,"#tmp"\n\t" \
 141         "andw   #-"STR(THREAD_SIZE)","#tmp"\n\t" \
 142         "movel  "#tmp",%%a2\n\t"
 143
 144 #endif
 145
 146 #endif /* __CF_M68K_ENTRY_H */