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-rw-r--r--arch/m68knommu/include/asm/entry.h182
1 files changed, 182 insertions, 0 deletions
diff --git a/arch/m68knommu/include/asm/entry.h b/arch/m68knommu/include/asm/entry.h
new file mode 100644
index 000000000000..c2553d26273d
--- /dev/null
+++ b/arch/m68knommu/include/asm/entry.h
@@ -0,0 +1,182 @@
+#ifndef __M68KNOMMU_ENTRY_H
+#define __M68KNOMMU_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 ] [ format & vector ]
+ * 2E(sp) - [ pc-hiword ] [ sr ]
+ * 30(sp) - [ pc-loword ] [ pc-hiword ]
+ * 32(sp) - [ format & vector ] [ pc-loword ]
+ * ^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^
+ * M68K COLDFIRE
+ */
+
+#define ALLOWINT 0xf8ff
+
+#ifdef __ASSEMBLY__
+
+/* process bits for task_struct.flags */
+PF_TRACESYS_OFF = 3
+PF_TRACESYS_BIT = 5
+PF_PTRACED_OFF = 3
+PF_PTRACED_BIT = 4
+PF_DTRACE_OFF = 1
+PF_DTRACE_BIT = 5
+
+LENOSYS = 38
+
+#define SWITCH_STACK_SIZE (6*4+4) /* Includes return address */
+
+/*
+ * This defines the normal kernel pt-regs layout.
+ *
+ * regs are a2-a6 and d6-d7 preserved by C code
+ * the kernel doesn't mess with usp unless it needs to
+ */
+
+#ifdef CONFIG_COLDFIRE
+/*
+ * This is made a little more tricky on the ColdFire. There is no
+ * separate kernel and user stack pointers. Need to artificially
+ * construct a usp in software... When doing this we need to disable
+ * interrupts, otherwise bad things could happen.
+ */
+.macro SAVE_ALL
+ move #0x2700,%sr /* disable intrs */
+ btst #5,%sp@(2) /* from user? */
+ bnes 6f /* no, skip */
+ movel %sp,sw_usp /* save user sp */
+ addql #8,sw_usp /* remove exception */
+ movel sw_ksp,%sp /* kernel sp */
+ subql #8,%sp /* room for exception */
+ clrl %sp@- /* stkadj */
+ movel %d0,%sp@- /* orig d0 */
+ movel %d0,%sp@- /* d0 */
+ lea %sp@(-32),%sp /* space for 8 regs */
+ moveml %d1-%d5/%a0-%a2,%sp@
+ movel sw_usp,%a0 /* get usp */
+ movel %a0@-,%sp@(PT_PC) /* copy exception program counter */
+ movel %a0@-,%sp@(PT_FORMATVEC)/* copy exception format/vector/sr */
+ bra 7f
+ 6:
+ clrl %sp@- /* stkadj */
+ movel %d0,%sp@- /* orig d0 */
+ movel %d0,%sp@- /* d0 */
+ lea %sp@(-32),%sp /* space for 8 regs */
+ moveml %d1-%d5/%a0-%a2,%sp@
+ 7:
+.endm
+
+.macro RESTORE_ALL
+ btst #5,%sp@(PT_SR) /* going user? */
+ bnes 8f /* no, skip */
+ move #0x2700,%sr /* disable intrs */
+ movel sw_usp,%a0 /* get usp */
+ movel %sp@(PT_PC),%a0@- /* copy exception program counter */
+ movel %sp@(PT_FORMATVEC),%a0@-/* copy exception format/vector/sr */
+ moveml %sp@,%d1-%d5/%a0-%a2
+ lea %sp@(32),%sp /* space for 8 regs */
+ movel %sp@+,%d0
+ addql #4,%sp /* orig d0 */
+ addl %sp@+,%sp /* stkadj */
+ addql #8,%sp /* remove exception */
+ movel %sp,sw_ksp /* save ksp */
+ subql #8,sw_usp /* set exception */
+ movel sw_usp,%sp /* restore usp */
+ rte
+ 8:
+ moveml %sp@,%d1-%d5/%a0-%a2
+ lea %sp@(32),%sp /* space for 8 regs */
+ movel %sp@+,%d0
+ addql #4,%sp /* orig d0 */
+ addl %sp@+,%sp /* stkadj */
+ rte
+.endm
+
+/*
+ * Quick exception save, use current stack only.
+ */
+.macro SAVE_LOCAL
+ move #0x2700,%sr /* disable intrs */
+ clrl %sp@- /* stkadj */
+ movel %d0,%sp@- /* orig d0 */
+ movel %d0,%sp@- /* d0 */
+ lea %sp@(-32),%sp /* space for 8 regs */
+ moveml %d1-%d5/%a0-%a2,%sp@
+.endm
+
+.macro RESTORE_LOCAL
+ moveml %sp@,%d1-%d5/%a0-%a2
+ lea %sp@(32),%sp /* space for 8 regs */
+ movel %sp@+,%d0
+ addql #4,%sp /* orig d0 */
+ addl %sp@+,%sp /* stkadj */
+ rte
+.endm
+
+.macro SAVE_SWITCH_STACK
+ lea %sp@(-24),%sp /* 6 regs */
+ moveml %a3-%a6/%d6-%d7,%sp@
+.endm
+
+.macro RESTORE_SWITCH_STACK
+ moveml %sp@,%a3-%a6/%d6-%d7
+ lea %sp@(24),%sp /* 6 regs */
+.endm
+
+/*
+ * Software copy of the user and kernel stack pointers... Ugh...
+ * Need these to get around ColdFire not having separate kernel
+ * and user stack pointers.
+ */
+.globl sw_usp
+.globl sw_ksp
+
+#else /* !CONFIG_COLDFIRE */
+
+/*
+ * Standard 68k interrupt entry and exit macros.
+ */
+.macro SAVE_ALL
+ clrl %sp@- /* stkadj */
+ movel %d0,%sp@- /* orig d0 */
+ movel %d0,%sp@- /* d0 */
+ moveml %d1-%d5/%a0-%a2,%sp@-
+.endm
+
+.macro RESTORE_ALL
+ moveml %sp@+,%a0-%a2/%d1-%d5
+ movel %sp@+,%d0
+ addql #4,%sp /* orig d0 */
+ addl %sp@+,%sp /* stkadj */
+ rte
+.endm
+
+.macro SAVE_SWITCH_STACK
+ moveml %a3-%a6/%d6-%d7,%sp@-
+.endm
+
+.macro RESTORE_SWITCH_STACK
+ moveml %sp@+,%a3-%a6/%d6-%d7
+.endm
+
+#endif /* !CONFIG_COLDFIRE */
+#endif /* __ASSEMBLY__ */
+#endif /* __M68KNOMMU_ENTRY_H */
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