1 files changed, 138 insertions, 0 deletions

diff --git a/include/asm-m68k/entry.h b/include/asm-m68k/entry.h
new file mode 100644
index 000000000000..0396495cd97d
--- /dev/null
+++ b/include/asm-m68k/entry.h
@@ -0,0 +1,138 @@
+#ifndef __M68K_ENTRY_H
+#define __M68K_ENTRY_H
+
+#include <linux/config.h>
+#include <asm/setup.h>
+#include <asm/page.h>
+
+/*
+ * Stack layout in 'ret_from_exception':
+ *
+ *      This allows access to the syscall arguments in registers d1-d5
+ *
+ *       0(sp) - d1
+ *       4(sp) - d2
+ *       8(sp) - d3
+ *       C(sp) - d4
+ *      10(sp) - d5
+ *      14(sp) - a0
+ *      18(sp) - a1
+ *      1C(sp) - a2
+ *      20(sp) - d0
+ *      24(sp) - orig_d0
+ *      28(sp) - stack adjustment
+ *      2C(sp) - sr
+ *      2E(sp) - pc
+ *      32(sp) - format & vector
+ */
+
+/*
+ * 97/05/14 Andreas: Register %a2 is now set to the current task throughout
+ *                   the whole kernel.
+ */
+
+/* the following macro is used when enabling interrupts */
+#if defined(MACH_ATARI_ONLY) && !defined(CONFIG_HADES)
+        /* block out HSYNC on the atari */
+#define ALLOWINT        (~0x400)
+#define MAX_NOINT_IPL   3
+#else
+        /* portable version */
+#define ALLOWINT        (~0x700)
+#define MAX_NOINT_IPL   0
+#endif /* machine compilation types */
+
+#ifdef __ASSEMBLY__
+
+#define curptr a2
+
+LFLUSH_I_AND_D = 0x00000808
+LSIGTRAP = 5
+
+/* process bits for task_struct.ptrace */
+PT_TRACESYS_OFF = 3
+PT_TRACESYS_BIT = 1
+PT_PTRACED_OFF = 3
+PT_PTRACED_BIT = 0
+PT_DTRACE_OFF = 3
+PT_DTRACE_BIT = 2
+
+#define SAVE_ALL_INT save_all_int
+#define SAVE_ALL_SYS save_all_sys
+#define RESTORE_ALL restore_all
+/*
+ * This defines the normal kernel pt-regs layout.
+ *
+ * regs a3-a6 and d6-d7 are preserved by C code
+ * the kernel doesn't mess with usp unless it needs to
+ */
+
+/*
+ * a -1 in the orig_d0 field signifies
+ * that the stack frame is NOT for syscall
+ */
+.macro  save_all_int
+        clrl    %sp@-           | stk_adj
+        pea     -1:w            | orig d0
+        movel   %d0,%sp@-       | d0
+        moveml  %d1-%d5/%a0-%a1/%curptr,%sp@-
+.endm
+
+.macro  save_all_sys
+        clrl    %sp@-           | stk_adj
+        movel   %d0,%sp@-       | orig d0
+        movel   %d0,%sp@-       | d0
+        moveml  %d1-%d5/%a0-%a1/%curptr,%sp@-
+.endm
+
+.macro  restore_all
+        moveml  %sp@+,%a0-%a1/%curptr/%d1-%d5
+        movel   %sp@+,%d0
+        addql   #4,%sp          | orig d0
+        addl    %sp@+,%sp       | stk adj
+        rte
+.endm
+
+#define SWITCH_STACK_SIZE (6*4+4)       /* includes return address */
+
+#define SAVE_SWITCH_STACK save_switch_stack
+#define RESTORE_SWITCH_STACK restore_switch_stack
+#define GET_CURRENT(tmp) get_current tmp
+
+.macro  save_switch_stack
+        moveml  %a3-%a6/%d6-%d7,%sp@-
+.endm
+
+.macro  restore_switch_stack
+        moveml  %sp@+,%a3-%a6/%d6-%d7
+.endm
+
+.macro  get_current reg=%d0
+        movel   %sp,\reg
+        andw    #-THREAD_SIZE,\reg
+        movel   \reg,%curptr
+        movel   %curptr@,%curptr
+.endm
+
+#else /* C source */
+
+#define STR(X) STR1(X)
+#define STR1(X) #X
+
+#define PT_OFF_ORIG_D0   0x24
+#define PT_OFF_FORMATVEC 0x32
+#define PT_OFF_SR        0x2C
+#define SAVE_ALL_INT                            \
+        "clrl   %%sp@-;"    /* stk_adj */       \
+        "pea    -1:w;"      /* orig d0 = -1 */  \
+        "movel  %%d0,%%sp@-;" /* d0 */          \
+        "moveml %%d1-%%d5/%%a0-%%a2,%%sp@-"
+#define GET_CURRENT(tmp) \
+        "movel  %%sp,"#tmp"\n\t" \
+        "andw   #-"STR(THREAD_SIZE)","#tmp"\n\t" \
+        "movel  "#tmp",%%a2\n\t" \
+        "movel  %%a2@,%%a2"
+
+#endif
+
+#endif /* __M68K_ENTRY_H */