| #ifndef __M68K_ENTRY_H |
| #define __M68K_ENTRY_H |
| |
| #include <asm/setup.h> |
| #include <asm/page.h> |
| #ifdef __ASSEMBLY__ |
| #include <asm/thread_info.h> |
| #endif |
| |
| /* |
| * 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 |
| */ |
| |
| /* the following macro is used when enabling interrupts */ |
| #if defined(MACH_ATARI_ONLY) |
| /* block out HSYNC = ipl 2 on the atari */ |
| #define ALLOWINT (~0x500) |
| #define MAX_NOINT_IPL 3 |
| #else |
| /* portable version */ |
| #define ALLOWINT (~0x700) |
| #define MAX_NOINT_IPL 0 |
| #endif /* machine compilation types */ |
| |
| #ifdef __ASSEMBLY__ |
| /* |
| * 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 |
| */ |
| #define SWITCH_STACK_SIZE (6*4+4) /* includes return address */ |
| |
| #ifdef CONFIG_COLDFIRE |
| #ifdef CONFIG_COLDFIRE_SW_A7 |
| /* |
| * This is made a little more tricky on older ColdFires. There is no |
| * separate supervisor and user stack pointers. Need to artificially |
| * construct a usp in software... When doing this we need to disable |
| * interrupts, otherwise bad things will happen. |
| */ |
| .globl sw_usp |
| .globl sw_ksp |
| |
| .macro SAVE_ALL_SYS |
| 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_OFF_PC) /* copy exception program counter */ |
| movel %a0@-,%sp@(PT_OFF_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 SAVE_ALL_INT |
| SAVE_ALL_SYS |
| moveq #-1,%d0 /* not system call entry */ |
| movel %d0,%sp@(PT_OFF_ORIG_D0) |
| .endm |
| |
| .macro RESTORE_USER |
| move #0x2700,%sr /* disable intrs */ |
| movel sw_usp,%a0 /* get usp */ |
| movel %sp@(PT_OFF_PC),%a0@- /* copy exception program counter */ |
| movel %sp@(PT_OFF_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 |
| .endm |
| |
| .macro RDUSP |
| movel sw_usp,%a3 |
| .endm |
| |
| .macro WRUSP |
| movel %a3,sw_usp |
| .endm |
| |
| #else /* !CONFIG_COLDFIRE_SW_A7 */ |
| /* |
| * Modern ColdFire parts have separate supervisor and user stack |
| * pointers. Simple load and restore macros for this case. |
| */ |
| .macro SAVE_ALL_SYS |
| 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 SAVE_ALL_INT |
| move #0x2700,%sr /* disable intrs */ |
| clrl %sp@- /* stkadj */ |
| pea -1:w /* orig d0 */ |
| movel %d0,%sp@- /* d0 */ |
| lea %sp@(-32),%sp /* space for 8 regs */ |
| moveml %d1-%d5/%a0-%a2,%sp@ |
| .endm |
| |
| .macro RESTORE_USER |
| 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 RDUSP |
| /*move %usp,%a3*/ |
| .word 0x4e6b |
| .endm |
| |
| .macro WRUSP |
| /*move %a3,%usp*/ |
| .word 0x4e63 |
| .endm |
| |
| #endif /* !CONFIG_COLDFIRE_SW_A7 */ |
| |
| .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 |
| |
| #else /* !CONFIG_COLDFIRE */ |
| |
| /* |
| * All other types of m68k parts (68000, 680x0, CPU32) have the same |
| * entry and exit code. |
| */ |
| |
| /* |
| * 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-%a2,%sp@- |
| .endm |
| |
| .macro SAVE_ALL_SYS |
| clrl %sp@- /* stk_adj */ |
| 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 /* stk adj */ |
| 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 */ |
| |
| /* |
| * Register %a2 is reserved and set to current task on MMU enabled systems. |
| * Non-MMU systems do not reserve %a2 in this way, and this definition is |
| * not used for them. |
| */ |
| #ifdef CONFIG_MMU |
| |
| #define curptr a2 |
| |
| #define GET_CURRENT(tmp) get_current tmp |
| .macro get_current reg=%d0 |
| movel %sp,\reg |
| andl #-THREAD_SIZE,\reg |
| movel \reg,%curptr |
| movel %curptr@,%curptr |
| .endm |
| |
| #else |
| |
| #define GET_CURRENT(tmp) |
| |
| #endif /* CONFIG_MMU */ |
| |
| #else /* C source */ |
| |
| #define STR(X) STR1(X) |
| #define STR1(X) #X |
| |
| #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 */ |