7 #include <asm/thread_info.h>
11 * Stack layout in 'ret_from_exception':
13 * This allows access to the syscall arguments in registers d1-d5
25 * 28(sp) - stack adjustment
26 * 2C(sp) - [ sr ] [ format & vector ]
27 * 2E(sp) - [ pc-hiword ] [ sr ]
28 * 30(sp) - [ pc-loword ] [ pc-hiword ]
29 * 32(sp) - [ format & vector ] [ pc-loword ]
30 * ^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^
34 /* the following macro is used when enabling interrupts */
35 #if defined(MACH_ATARI_ONLY)
36 /* block out HSYNC on the atari */
37 #define ALLOWINT (~0x400)
38 #define MAX_NOINT_IPL 3
40 /* portable version */
41 #define ALLOWINT (~0x700)
42 #define MAX_NOINT_IPL 0
43 #endif /* machine compilation types */
47 * This defines the normal kernel pt-regs layout.
49 * regs a3-a6 and d6-d7 are preserved by C code
50 * the kernel doesn't mess with usp unless it needs to
52 #define SWITCH_STACK_SIZE (6*4+4) /* includes return address */
54 #ifdef CONFIG_COLDFIRE
55 #ifdef CONFIG_COLDFIRE_SW_A7
57 * This is made a little more tricky on older ColdFires. There is no
58 * separate supervisor and user stack pointers. Need to artificially
59 * construct a usp in software... When doing this we need to disable
60 * interrupts, otherwise bad things will happen.
66 move #0x2700,%sr /* disable intrs */
67 btst #5,%sp@(2) /* from user? */
68 bnes 6f /* no, skip */
69 movel %sp,sw_usp /* save user sp */
70 addql #8,sw_usp /* remove exception */
71 movel sw_ksp,%sp /* kernel sp */
72 subql #8,%sp /* room for exception */
73 clrl %sp@- /* stkadj */
74 movel %d0,%sp@- /* orig d0 */
75 movel %d0,%sp@- /* d0 */
76 lea %sp@(-32),%sp /* space for 8 regs */
77 moveml %d1-%d5/%a0-%a2,%sp@
78 movel sw_usp,%a0 /* get usp */
79 movel %a0@-,%sp@(PT_OFF_PC) /* copy exception program counter */
80 movel %a0@-,%sp@(PT_OFF_FORMATVEC)/*copy exception format/vector/sr */
83 clrl %sp@- /* stkadj */
84 movel %d0,%sp@- /* orig d0 */
85 movel %d0,%sp@- /* d0 */
86 lea %sp@(-32),%sp /* space for 8 regs */
87 moveml %d1-%d5/%a0-%a2,%sp@
93 moveq #-1,%d0 /* not system call entry */
94 movel %d0,%sp@(PT_OFF_ORIG_D0)
98 move #0x2700,%sr /* disable intrs */
99 movel sw_usp,%a0 /* get usp */
100 movel %sp@(PT_OFF_PC),%a0@- /* copy exception program counter */
101 movel %sp@(PT_OFF_FORMATVEC),%a0@-/*copy exception format/vector/sr */
102 moveml %sp@,%d1-%d5/%a0-%a2
103 lea %sp@(32),%sp /* space for 8 regs */
105 addql #4,%sp /* orig d0 */
106 addl %sp@+,%sp /* stkadj */
107 addql #8,%sp /* remove exception */
108 movel %sp,sw_ksp /* save ksp */
109 subql #8,sw_usp /* set exception */
110 movel sw_usp,%sp /* restore usp */
122 #else /* !CONFIG_COLDFIRE_SW_A7 */
124 * Modern ColdFire parts have separate supervisor and user stack
125 * pointers. Simple load and restore macros for this case.
128 move #0x2700,%sr /* disable intrs */
129 clrl %sp@- /* stkadj */
130 movel %d0,%sp@- /* orig d0 */
131 movel %d0,%sp@- /* d0 */
132 lea %sp@(-32),%sp /* space for 8 regs */
133 moveml %d1-%d5/%a0-%a2,%sp@
137 move #0x2700,%sr /* disable intrs */
138 clrl %sp@- /* stkadj */
139 pea -1:w /* orig d0 */
140 movel %d0,%sp@- /* d0 */
141 lea %sp@(-32),%sp /* space for 8 regs */
142 moveml %d1-%d5/%a0-%a2,%sp@
146 moveml %sp@,%d1-%d5/%a0-%a2
147 lea %sp@(32),%sp /* space for 8 regs */
149 addql #4,%sp /* orig d0 */
150 addl %sp@+,%sp /* stkadj */
164 #endif /* !CONFIG_COLDFIRE_SW_A7 */
166 .macro SAVE_SWITCH_STACK
167 lea %sp@(-24),%sp /* 6 regs */
168 moveml %a3-%a6/%d6-%d7,%sp@
171 .macro RESTORE_SWITCH_STACK
172 moveml %sp@,%a3-%a6/%d6-%d7
173 lea %sp@(24),%sp /* 6 regs */
176 #else /* !CONFIG_COLDFIRE */
179 * All other types of m68k parts (68000, 680x0, CPU32) have the same
180 * entry and exit code.
184 * a -1 in the orig_d0 field signifies
185 * that the stack frame is NOT for syscall
188 clrl %sp@- /* stk_adj */
189 pea -1:w /* orig d0 */
190 movel %d0,%sp@- /* d0 */
191 moveml %d1-%d5/%a0-%a2,%sp@-
195 clrl %sp@- /* stk_adj */
196 movel %d0,%sp@- /* orig d0 */
197 movel %d0,%sp@- /* d0 */
198 moveml %d1-%d5/%a0-%a2,%sp@-
202 moveml %sp@+,%a0-%a2/%d1-%d5
204 addql #4,%sp /* orig d0 */
205 addl %sp@+,%sp /* stk adj */
210 .macro SAVE_SWITCH_STACK
211 moveml %a3-%a6/%d6-%d7,%sp@-
214 .macro RESTORE_SWITCH_STACK
215 moveml %sp@+,%a3-%a6/%d6-%d7
218 #endif /* !CONFIG_COLDFIRE */
221 * Register %a2 is reserved and set to current task on MMU enabled systems.
222 * Non-MMU systems do not reserve %a2 in this way, and this definition is
229 #define GET_CURRENT(tmp) get_current tmp
230 .macro get_current reg=%d0
232 andl #-THREAD_SIZE,\reg
234 movel %curptr@,%curptr
239 #define GET_CURRENT(tmp)
241 #endif /* CONFIG_MMU */
245 #define STR(X) STR1(X)
248 #define SAVE_ALL_INT \
249 "clrl %%sp@-;" /* stk_adj */ \
250 "pea -1:w;" /* orig d0 = -1 */ \
251 "movel %%d0,%%sp@-;" /* d0 */ \
252 "moveml %%d1-%%d5/%%a0-%%a2,%%sp@-"
254 #define GET_CURRENT(tmp) \
255 "movel %%sp,"#tmp"\n\t" \
256 "andw #-"STR(THREAD_SIZE)","#tmp"\n\t" \
257 "movel "#tmp",%%a2\n\t" \
262 #endif /* __M68K_ENTRY_H */