diff options
Diffstat (limited to 'arch/m68knommu/include/asm/entry.h')
| -rw-r--r-- | arch/m68knommu/include/asm/entry.h | 182 |
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 00000000000..c2553d26273 --- /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 */ |