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Diffstat (limited to 'arch/m68k/include/asm/entry_mm.h')
-rw-r--r--arch/m68k/include/asm/entry_mm.h137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/m68k/include/asm/entry_mm.h b/arch/m68k/include/asm/entry_mm.h
new file mode 100644
index 00000000000..5202f5a5b42
--- /dev/null
+++ b/arch/m68k/include/asm/entry_mm.h
@@ -0,0 +1,137 @@
+#ifndef __M68K_ENTRY_H
+#define __M68K_ENTRY_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)
+ /* 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 */