]>
Commit | Line | Data |
---|---|---|
9994a338 PM |
1 | /* |
2 | * arch/ppc64/kernel/entry.S | |
3 | * | |
4 | * PowerPC version | |
5 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) | |
6 | * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP | |
7 | * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> | |
8 | * Adapted for Power Macintosh by Paul Mackerras. | |
9 | * Low-level exception handlers and MMU support | |
10 | * rewritten by Paul Mackerras. | |
11 | * Copyright (C) 1996 Paul Mackerras. | |
12 | * MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net). | |
13 | * | |
14 | * This file contains the system call entry code, context switch | |
15 | * code, and exception/interrupt return code for PowerPC. | |
16 | * | |
17 | * This program is free software; you can redistribute it and/or | |
18 | * modify it under the terms of the GNU General Public License | |
19 | * as published by the Free Software Foundation; either version | |
20 | * 2 of the License, or (at your option) any later version. | |
21 | */ | |
22 | ||
23 | #include <linux/config.h> | |
24 | #include <linux/errno.h> | |
25 | #include <asm/unistd.h> | |
26 | #include <asm/processor.h> | |
27 | #include <asm/page.h> | |
28 | #include <asm/mmu.h> | |
29 | #include <asm/thread_info.h> | |
30 | #include <asm/ppc_asm.h> | |
31 | #include <asm/asm-offsets.h> | |
32 | #include <asm/cputable.h> | |
33 | ||
34 | #ifdef CONFIG_PPC_ISERIES | |
35 | #define DO_SOFT_DISABLE | |
36 | #endif | |
37 | ||
38 | /* | |
39 | * System calls. | |
40 | */ | |
41 | .section ".toc","aw" | |
42 | .SYS_CALL_TABLE: | |
43 | .tc .sys_call_table[TC],.sys_call_table | |
44 | ||
45 | /* This value is used to mark exception frames on the stack. */ | |
46 | exception_marker: | |
47 | .tc ID_72656773_68657265[TC],0x7265677368657265 | |
48 | ||
49 | .section ".text" | |
50 | .align 7 | |
51 | ||
52 | #undef SHOW_SYSCALLS | |
53 | ||
54 | .globl system_call_common | |
55 | system_call_common: | |
56 | andi. r10,r12,MSR_PR | |
57 | mr r10,r1 | |
58 | addi r1,r1,-INT_FRAME_SIZE | |
59 | beq- 1f | |
60 | ld r1,PACAKSAVE(r13) | |
61 | 1: std r10,0(r1) | |
62 | std r11,_NIP(r1) | |
63 | std r12,_MSR(r1) | |
64 | std r0,GPR0(r1) | |
65 | std r10,GPR1(r1) | |
66 | std r2,GPR2(r1) | |
67 | std r3,GPR3(r1) | |
68 | std r4,GPR4(r1) | |
69 | std r5,GPR5(r1) | |
70 | std r6,GPR6(r1) | |
71 | std r7,GPR7(r1) | |
72 | std r8,GPR8(r1) | |
73 | li r11,0 | |
74 | std r11,GPR9(r1) | |
75 | std r11,GPR10(r1) | |
76 | std r11,GPR11(r1) | |
77 | std r11,GPR12(r1) | |
78 | std r9,GPR13(r1) | |
79 | crclr so | |
80 | mfcr r9 | |
81 | mflr r10 | |
82 | li r11,0xc01 | |
83 | std r9,_CCR(r1) | |
84 | std r10,_LINK(r1) | |
85 | std r11,_TRAP(r1) | |
86 | mfxer r9 | |
87 | mfctr r10 | |
88 | std r9,_XER(r1) | |
89 | std r10,_CTR(r1) | |
90 | std r3,ORIG_GPR3(r1) | |
91 | ld r2,PACATOC(r13) | |
92 | addi r9,r1,STACK_FRAME_OVERHEAD | |
93 | ld r11,exception_marker@toc(r2) | |
94 | std r11,-16(r9) /* "regshere" marker */ | |
95 | #ifdef CONFIG_PPC_ISERIES | |
96 | /* Hack for handling interrupts when soft-enabling on iSeries */ | |
97 | cmpdi cr1,r0,0x5555 /* syscall 0x5555 */ | |
98 | andi. r10,r12,MSR_PR /* from kernel */ | |
99 | crand 4*cr0+eq,4*cr1+eq,4*cr0+eq | |
100 | beq hardware_interrupt_entry | |
101 | lbz r10,PACAPROCENABLED(r13) | |
102 | std r10,SOFTE(r1) | |
103 | #endif | |
104 | mfmsr r11 | |
105 | ori r11,r11,MSR_EE | |
106 | mtmsrd r11,1 | |
107 | ||
108 | #ifdef SHOW_SYSCALLS | |
109 | bl .do_show_syscall | |
110 | REST_GPR(0,r1) | |
111 | REST_4GPRS(3,r1) | |
112 | REST_2GPRS(7,r1) | |
113 | addi r9,r1,STACK_FRAME_OVERHEAD | |
114 | #endif | |
115 | clrrdi r11,r1,THREAD_SHIFT | |
116 | li r12,0 | |
117 | ld r10,TI_FLAGS(r11) | |
118 | stb r12,TI_SC_NOERR(r11) | |
119 | andi. r11,r10,_TIF_SYSCALL_T_OR_A | |
120 | bne- syscall_dotrace | |
121 | syscall_dotrace_cont: | |
122 | cmpldi 0,r0,NR_syscalls | |
123 | bge- syscall_enosys | |
124 | ||
125 | system_call: /* label this so stack traces look sane */ | |
126 | /* | |
127 | * Need to vector to 32 Bit or default sys_call_table here, | |
128 | * based on caller's run-mode / personality. | |
129 | */ | |
130 | ld r11,.SYS_CALL_TABLE@toc(2) | |
131 | andi. r10,r10,_TIF_32BIT | |
132 | beq 15f | |
133 | addi r11,r11,8 /* use 32-bit syscall entries */ | |
134 | clrldi r3,r3,32 | |
135 | clrldi r4,r4,32 | |
136 | clrldi r5,r5,32 | |
137 | clrldi r6,r6,32 | |
138 | clrldi r7,r7,32 | |
139 | clrldi r8,r8,32 | |
140 | 15: | |
141 | slwi r0,r0,4 | |
142 | ldx r10,r11,r0 /* Fetch system call handler [ptr] */ | |
143 | mtctr r10 | |
144 | bctrl /* Call handler */ | |
145 | ||
146 | syscall_exit: | |
147 | #ifdef SHOW_SYSCALLS | |
148 | std r3,GPR3(r1) | |
149 | bl .do_show_syscall_exit | |
150 | ld r3,GPR3(r1) | |
151 | #endif | |
152 | std r3,RESULT(r1) | |
153 | ld r5,_CCR(r1) | |
154 | li r10,-_LAST_ERRNO | |
155 | cmpld r3,r10 | |
156 | clrrdi r12,r1,THREAD_SHIFT | |
157 | bge- syscall_error | |
158 | syscall_error_cont: | |
159 | ||
160 | /* check for syscall tracing or audit */ | |
161 | ld r9,TI_FLAGS(r12) | |
162 | andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP) | |
163 | bne- syscall_exit_trace | |
164 | syscall_exit_trace_cont: | |
165 | ||
166 | /* disable interrupts so current_thread_info()->flags can't change, | |
167 | and so that we don't get interrupted after loading SRR0/1. */ | |
168 | ld r8,_MSR(r1) | |
169 | andi. r10,r8,MSR_RI | |
170 | beq- unrecov_restore | |
171 | mfmsr r10 | |
172 | rldicl r10,r10,48,1 | |
173 | rotldi r10,r10,16 | |
174 | mtmsrd r10,1 | |
175 | ld r9,TI_FLAGS(r12) | |
176 | andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SIGPENDING|_TIF_NEED_RESCHED) | |
177 | bne- syscall_exit_work | |
178 | ld r7,_NIP(r1) | |
179 | stdcx. r0,0,r1 /* to clear the reservation */ | |
180 | andi. r6,r8,MSR_PR | |
181 | ld r4,_LINK(r1) | |
182 | beq- 1f /* only restore r13 if */ | |
183 | ld r13,GPR13(r1) /* returning to usermode */ | |
184 | 1: ld r2,GPR2(r1) | |
185 | li r12,MSR_RI | |
186 | andc r10,r10,r12 | |
187 | mtmsrd r10,1 /* clear MSR.RI */ | |
188 | ld r1,GPR1(r1) | |
189 | mtlr r4 | |
190 | mtcr r5 | |
191 | mtspr SPRN_SRR0,r7 | |
192 | mtspr SPRN_SRR1,r8 | |
193 | rfid | |
194 | b . /* prevent speculative execution */ | |
195 | ||
196 | syscall_enosys: | |
197 | li r3,-ENOSYS | |
198 | std r3,RESULT(r1) | |
199 | clrrdi r12,r1,THREAD_SHIFT | |
200 | ld r5,_CCR(r1) | |
201 | ||
202 | syscall_error: | |
203 | lbz r11,TI_SC_NOERR(r12) | |
204 | cmpwi 0,r11,0 | |
205 | bne- syscall_error_cont | |
206 | neg r3,r3 | |
207 | oris r5,r5,0x1000 /* Set SO bit in CR */ | |
208 | std r5,_CCR(r1) | |
209 | b syscall_error_cont | |
210 | ||
211 | /* Traced system call support */ | |
212 | syscall_dotrace: | |
213 | bl .save_nvgprs | |
214 | addi r3,r1,STACK_FRAME_OVERHEAD | |
215 | bl .do_syscall_trace_enter | |
216 | ld r0,GPR0(r1) /* Restore original registers */ | |
217 | ld r3,GPR3(r1) | |
218 | ld r4,GPR4(r1) | |
219 | ld r5,GPR5(r1) | |
220 | ld r6,GPR6(r1) | |
221 | ld r7,GPR7(r1) | |
222 | ld r8,GPR8(r1) | |
223 | addi r9,r1,STACK_FRAME_OVERHEAD | |
224 | clrrdi r10,r1,THREAD_SHIFT | |
225 | ld r10,TI_FLAGS(r10) | |
226 | b syscall_dotrace_cont | |
227 | ||
228 | syscall_exit_trace: | |
229 | std r3,GPR3(r1) | |
230 | bl .save_nvgprs | |
231 | addi r3,r1,STACK_FRAME_OVERHEAD | |
232 | bl .do_syscall_trace_leave | |
233 | REST_NVGPRS(r1) | |
234 | ld r3,GPR3(r1) | |
235 | ld r5,_CCR(r1) | |
236 | clrrdi r12,r1,THREAD_SHIFT | |
237 | b syscall_exit_trace_cont | |
238 | ||
239 | /* Stuff to do on exit from a system call. */ | |
240 | syscall_exit_work: | |
241 | std r3,GPR3(r1) | |
242 | std r5,_CCR(r1) | |
243 | b .ret_from_except_lite | |
244 | ||
245 | /* Save non-volatile GPRs, if not already saved. */ | |
246 | _GLOBAL(save_nvgprs) | |
247 | ld r11,_TRAP(r1) | |
248 | andi. r0,r11,1 | |
249 | beqlr- | |
250 | SAVE_NVGPRS(r1) | |
251 | clrrdi r0,r11,1 | |
252 | std r0,_TRAP(r1) | |
253 | blr | |
254 | ||
255 | /* | |
256 | * The sigsuspend and rt_sigsuspend system calls can call do_signal | |
257 | * and thus put the process into the stopped state where we might | |
258 | * want to examine its user state with ptrace. Therefore we need | |
259 | * to save all the nonvolatile registers (r14 - r31) before calling | |
260 | * the C code. Similarly, fork, vfork and clone need the full | |
261 | * register state on the stack so that it can be copied to the child. | |
262 | */ | |
263 | _GLOBAL(ppc32_sigsuspend) | |
264 | bl .save_nvgprs | |
265 | bl .sys32_sigsuspend | |
266 | b 70f | |
267 | ||
268 | _GLOBAL(ppc64_rt_sigsuspend) | |
269 | bl .save_nvgprs | |
270 | bl .sys_rt_sigsuspend | |
271 | b 70f | |
272 | ||
273 | _GLOBAL(ppc32_rt_sigsuspend) | |
274 | bl .save_nvgprs | |
275 | bl .sys32_rt_sigsuspend | |
276 | 70: cmpdi 0,r3,0 | |
277 | /* If it returned an error, we need to return via syscall_exit to set | |
278 | the SO bit in cr0 and potentially stop for ptrace. */ | |
279 | bne syscall_exit | |
280 | /* If sigsuspend() returns zero, we are going into a signal handler. We | |
281 | may need to call audit_syscall_exit() to mark the exit from sigsuspend() */ | |
282 | #ifdef CONFIG_AUDIT | |
283 | ld r3,PACACURRENT(r13) | |
284 | ld r4,AUDITCONTEXT(r3) | |
285 | cmpdi 0,r4,0 | |
286 | beq .ret_from_except /* No audit_context: Leave immediately. */ | |
287 | li r4, 2 /* AUDITSC_FAILURE */ | |
288 | li r5,-4 /* It's always -EINTR */ | |
289 | bl .audit_syscall_exit | |
290 | #endif | |
291 | b .ret_from_except | |
292 | ||
293 | _GLOBAL(ppc_fork) | |
294 | bl .save_nvgprs | |
295 | bl .sys_fork | |
296 | b syscall_exit | |
297 | ||
298 | _GLOBAL(ppc_vfork) | |
299 | bl .save_nvgprs | |
300 | bl .sys_vfork | |
301 | b syscall_exit | |
302 | ||
303 | _GLOBAL(ppc_clone) | |
304 | bl .save_nvgprs | |
305 | bl .sys_clone | |
306 | b syscall_exit | |
307 | ||
308 | _GLOBAL(ppc32_swapcontext) | |
309 | bl .save_nvgprs | |
310 | bl .sys32_swapcontext | |
311 | b 80f | |
312 | ||
313 | _GLOBAL(ppc64_swapcontext) | |
314 | bl .save_nvgprs | |
315 | bl .sys_swapcontext | |
316 | b 80f | |
317 | ||
318 | _GLOBAL(ppc32_sigreturn) | |
319 | bl .sys32_sigreturn | |
320 | b 80f | |
321 | ||
322 | _GLOBAL(ppc32_rt_sigreturn) | |
323 | bl .sys32_rt_sigreturn | |
324 | b 80f | |
325 | ||
326 | _GLOBAL(ppc64_rt_sigreturn) | |
327 | bl .sys_rt_sigreturn | |
328 | ||
329 | 80: cmpdi 0,r3,0 | |
330 | blt syscall_exit | |
331 | clrrdi r4,r1,THREAD_SHIFT | |
332 | ld r4,TI_FLAGS(r4) | |
333 | andi. r4,r4,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP) | |
334 | beq+ 81f | |
335 | addi r3,r1,STACK_FRAME_OVERHEAD | |
336 | bl .do_syscall_trace_leave | |
337 | 81: b .ret_from_except | |
338 | ||
339 | _GLOBAL(ret_from_fork) | |
340 | bl .schedule_tail | |
341 | REST_NVGPRS(r1) | |
342 | li r3,0 | |
343 | b syscall_exit | |
344 | ||
345 | /* | |
346 | * This routine switches between two different tasks. The process | |
347 | * state of one is saved on its kernel stack. Then the state | |
348 | * of the other is restored from its kernel stack. The memory | |
349 | * management hardware is updated to the second process's state. | |
350 | * Finally, we can return to the second process, via ret_from_except. | |
351 | * On entry, r3 points to the THREAD for the current task, r4 | |
352 | * points to the THREAD for the new task. | |
353 | * | |
354 | * Note: there are two ways to get to the "going out" portion | |
355 | * of this code; either by coming in via the entry (_switch) | |
356 | * or via "fork" which must set up an environment equivalent | |
357 | * to the "_switch" path. If you change this you'll have to change | |
358 | * the fork code also. | |
359 | * | |
360 | * The code which creates the new task context is in 'copy_thread' | |
361 | * in arch/ppc64/kernel/process.c | |
362 | */ | |
363 | .align 7 | |
364 | _GLOBAL(_switch) | |
365 | mflr r0 | |
366 | std r0,16(r1) | |
367 | stdu r1,-SWITCH_FRAME_SIZE(r1) | |
368 | /* r3-r13 are caller saved -- Cort */ | |
369 | SAVE_8GPRS(14, r1) | |
370 | SAVE_10GPRS(22, r1) | |
371 | mflr r20 /* Return to switch caller */ | |
372 | mfmsr r22 | |
373 | li r0, MSR_FP | |
374 | #ifdef CONFIG_ALTIVEC | |
375 | BEGIN_FTR_SECTION | |
376 | oris r0,r0,MSR_VEC@h /* Disable altivec */ | |
377 | mfspr r24,SPRN_VRSAVE /* save vrsave register value */ | |
378 | std r24,THREAD_VRSAVE(r3) | |
379 | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | |
380 | #endif /* CONFIG_ALTIVEC */ | |
381 | and. r0,r0,r22 | |
382 | beq+ 1f | |
383 | andc r22,r22,r0 | |
384 | mtmsrd r22 | |
385 | isync | |
386 | 1: std r20,_NIP(r1) | |
387 | mfcr r23 | |
388 | std r23,_CCR(r1) | |
389 | std r1,KSP(r3) /* Set old stack pointer */ | |
390 | ||
391 | #ifdef CONFIG_SMP | |
392 | /* We need a sync somewhere here to make sure that if the | |
393 | * previous task gets rescheduled on another CPU, it sees all | |
394 | * stores it has performed on this one. | |
395 | */ | |
396 | sync | |
397 | #endif /* CONFIG_SMP */ | |
398 | ||
399 | addi r6,r4,-THREAD /* Convert THREAD to 'current' */ | |
400 | std r6,PACACURRENT(r13) /* Set new 'current' */ | |
401 | ||
402 | ld r8,KSP(r4) /* new stack pointer */ | |
403 | BEGIN_FTR_SECTION | |
404 | clrrdi r6,r8,28 /* get its ESID */ | |
405 | clrrdi r9,r1,28 /* get current sp ESID */ | |
406 | clrldi. r0,r6,2 /* is new ESID c00000000? */ | |
407 | cmpd cr1,r6,r9 /* or is new ESID the same as current ESID? */ | |
408 | cror eq,4*cr1+eq,eq | |
409 | beq 2f /* if yes, don't slbie it */ | |
410 | ||
411 | /* Bolt in the new stack SLB entry */ | |
412 | ld r7,KSP_VSID(r4) /* Get new stack's VSID */ | |
413 | oris r0,r6,(SLB_ESID_V)@h | |
414 | ori r0,r0,(SLB_NUM_BOLTED-1)@l | |
415 | slbie r6 | |
416 | slbie r6 /* Workaround POWER5 < DD2.1 issue */ | |
417 | slbmte r7,r0 | |
418 | isync | |
419 | ||
420 | 2: | |
421 | END_FTR_SECTION_IFSET(CPU_FTR_SLB) | |
422 | clrrdi r7,r8,THREAD_SHIFT /* base of new stack */ | |
423 | /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE | |
424 | because we don't need to leave the 288-byte ABI gap at the | |
425 | top of the kernel stack. */ | |
426 | addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE | |
427 | ||
428 | mr r1,r8 /* start using new stack pointer */ | |
429 | std r7,PACAKSAVE(r13) | |
430 | ||
431 | ld r6,_CCR(r1) | |
432 | mtcrf 0xFF,r6 | |
433 | ||
434 | #ifdef CONFIG_ALTIVEC | |
435 | BEGIN_FTR_SECTION | |
436 | ld r0,THREAD_VRSAVE(r4) | |
437 | mtspr SPRN_VRSAVE,r0 /* if G4, restore VRSAVE reg */ | |
438 | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | |
439 | #endif /* CONFIG_ALTIVEC */ | |
440 | ||
441 | /* r3-r13 are destroyed -- Cort */ | |
442 | REST_8GPRS(14, r1) | |
443 | REST_10GPRS(22, r1) | |
444 | ||
445 | /* convert old thread to its task_struct for return value */ | |
446 | addi r3,r3,-THREAD | |
447 | ld r7,_NIP(r1) /* Return to _switch caller in new task */ | |
448 | mtlr r7 | |
449 | addi r1,r1,SWITCH_FRAME_SIZE | |
450 | blr | |
451 | ||
452 | .align 7 | |
453 | _GLOBAL(ret_from_except) | |
454 | ld r11,_TRAP(r1) | |
455 | andi. r0,r11,1 | |
456 | bne .ret_from_except_lite | |
457 | REST_NVGPRS(r1) | |
458 | ||
459 | _GLOBAL(ret_from_except_lite) | |
460 | /* | |
461 | * Disable interrupts so that current_thread_info()->flags | |
462 | * can't change between when we test it and when we return | |
463 | * from the interrupt. | |
464 | */ | |
465 | mfmsr r10 /* Get current interrupt state */ | |
466 | rldicl r9,r10,48,1 /* clear MSR_EE */ | |
467 | rotldi r9,r9,16 | |
468 | mtmsrd r9,1 /* Update machine state */ | |
469 | ||
470 | #ifdef CONFIG_PREEMPT | |
471 | clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */ | |
472 | li r0,_TIF_NEED_RESCHED /* bits to check */ | |
473 | ld r3,_MSR(r1) | |
474 | ld r4,TI_FLAGS(r9) | |
475 | /* Move MSR_PR bit in r3 to _TIF_SIGPENDING position in r0 */ | |
476 | rlwimi r0,r3,32+TIF_SIGPENDING-MSR_PR_LG,_TIF_SIGPENDING | |
477 | and. r0,r4,r0 /* check NEED_RESCHED and maybe SIGPENDING */ | |
478 | bne do_work | |
479 | ||
480 | #else /* !CONFIG_PREEMPT */ | |
481 | ld r3,_MSR(r1) /* Returning to user mode? */ | |
482 | andi. r3,r3,MSR_PR | |
483 | beq restore /* if not, just restore regs and return */ | |
484 | ||
485 | /* Check current_thread_info()->flags */ | |
486 | clrrdi r9,r1,THREAD_SHIFT | |
487 | ld r4,TI_FLAGS(r9) | |
488 | andi. r0,r4,_TIF_USER_WORK_MASK | |
489 | bne do_work | |
490 | #endif | |
491 | ||
492 | restore: | |
493 | #ifdef CONFIG_PPC_ISERIES | |
494 | ld r5,SOFTE(r1) | |
495 | cmpdi 0,r5,0 | |
496 | beq 4f | |
497 | /* Check for pending interrupts (iSeries) */ | |
498 | ld r3,PACALPPACA+LPPACAANYINT(r13) | |
499 | cmpdi r3,0 | |
500 | beq+ 4f /* skip do_IRQ if no interrupts */ | |
501 | ||
502 | li r3,0 | |
503 | stb r3,PACAPROCENABLED(r13) /* ensure we are soft-disabled */ | |
504 | ori r10,r10,MSR_EE | |
505 | mtmsrd r10 /* hard-enable again */ | |
506 | addi r3,r1,STACK_FRAME_OVERHEAD | |
507 | bl .do_IRQ | |
508 | b .ret_from_except_lite /* loop back and handle more */ | |
509 | ||
510 | 4: stb r5,PACAPROCENABLED(r13) | |
511 | #endif | |
512 | ||
513 | ld r3,_MSR(r1) | |
514 | andi. r0,r3,MSR_RI | |
515 | beq- unrecov_restore | |
516 | ||
517 | andi. r0,r3,MSR_PR | |
518 | ||
519 | /* | |
520 | * r13 is our per cpu area, only restore it if we are returning to | |
521 | * userspace | |
522 | */ | |
523 | beq 1f | |
524 | REST_GPR(13, r1) | |
525 | 1: | |
526 | ld r3,_CTR(r1) | |
527 | ld r0,_LINK(r1) | |
528 | mtctr r3 | |
529 | mtlr r0 | |
530 | ld r3,_XER(r1) | |
531 | mtspr SPRN_XER,r3 | |
532 | ||
533 | REST_8GPRS(5, r1) | |
534 | ||
535 | stdcx. r0,0,r1 /* to clear the reservation */ | |
536 | ||
537 | mfmsr r0 | |
538 | li r2, MSR_RI | |
539 | andc r0,r0,r2 | |
540 | mtmsrd r0,1 | |
541 | ||
542 | ld r0,_MSR(r1) | |
543 | mtspr SPRN_SRR1,r0 | |
544 | ||
545 | ld r2,_CCR(r1) | |
546 | mtcrf 0xFF,r2 | |
547 | ld r2,_NIP(r1) | |
548 | mtspr SPRN_SRR0,r2 | |
549 | ||
550 | ld r0,GPR0(r1) | |
551 | ld r2,GPR2(r1) | |
552 | ld r3,GPR3(r1) | |
553 | ld r4,GPR4(r1) | |
554 | ld r1,GPR1(r1) | |
555 | ||
556 | rfid | |
557 | b . /* prevent speculative execution */ | |
558 | ||
559 | /* Note: this must change if we start using the TIF_NOTIFY_RESUME bit */ | |
560 | do_work: | |
561 | #ifdef CONFIG_PREEMPT | |
562 | andi. r0,r3,MSR_PR /* Returning to user mode? */ | |
563 | bne user_work | |
564 | /* Check that preempt_count() == 0 and interrupts are enabled */ | |
565 | lwz r8,TI_PREEMPT(r9) | |
566 | cmpwi cr1,r8,0 | |
567 | #ifdef CONFIG_PPC_ISERIES | |
568 | ld r0,SOFTE(r1) | |
569 | cmpdi r0,0 | |
570 | #else | |
571 | andi. r0,r3,MSR_EE | |
572 | #endif | |
573 | crandc eq,cr1*4+eq,eq | |
574 | bne restore | |
575 | /* here we are preempting the current task */ | |
576 | 1: | |
577 | #ifdef CONFIG_PPC_ISERIES | |
578 | li r0,1 | |
579 | stb r0,PACAPROCENABLED(r13) | |
580 | #endif | |
581 | ori r10,r10,MSR_EE | |
582 | mtmsrd r10,1 /* reenable interrupts */ | |
583 | bl .preempt_schedule | |
584 | mfmsr r10 | |
585 | clrrdi r9,r1,THREAD_SHIFT | |
586 | rldicl r10,r10,48,1 /* disable interrupts again */ | |
587 | rotldi r10,r10,16 | |
588 | mtmsrd r10,1 | |
589 | ld r4,TI_FLAGS(r9) | |
590 | andi. r0,r4,_TIF_NEED_RESCHED | |
591 | bne 1b | |
592 | b restore | |
593 | ||
594 | user_work: | |
595 | #endif | |
596 | /* Enable interrupts */ | |
597 | ori r10,r10,MSR_EE | |
598 | mtmsrd r10,1 | |
599 | ||
600 | andi. r0,r4,_TIF_NEED_RESCHED | |
601 | beq 1f | |
602 | bl .schedule | |
603 | b .ret_from_except_lite | |
604 | ||
605 | 1: bl .save_nvgprs | |
606 | li r3,0 | |
607 | addi r4,r1,STACK_FRAME_OVERHEAD | |
608 | bl .do_signal | |
609 | b .ret_from_except | |
610 | ||
611 | unrecov_restore: | |
612 | addi r3,r1,STACK_FRAME_OVERHEAD | |
613 | bl .unrecoverable_exception | |
614 | b unrecov_restore | |
615 | ||
616 | #ifdef CONFIG_PPC_RTAS | |
617 | /* | |
618 | * On CHRP, the Run-Time Abstraction Services (RTAS) have to be | |
619 | * called with the MMU off. | |
620 | * | |
621 | * In addition, we need to be in 32b mode, at least for now. | |
622 | * | |
623 | * Note: r3 is an input parameter to rtas, so don't trash it... | |
624 | */ | |
625 | _GLOBAL(enter_rtas) | |
626 | mflr r0 | |
627 | std r0,16(r1) | |
628 | stdu r1,-RTAS_FRAME_SIZE(r1) /* Save SP and create stack space. */ | |
629 | ||
630 | /* Because RTAS is running in 32b mode, it clobbers the high order half | |
631 | * of all registers that it saves. We therefore save those registers | |
632 | * RTAS might touch to the stack. (r0, r3-r13 are caller saved) | |
633 | */ | |
634 | SAVE_GPR(2, r1) /* Save the TOC */ | |
635 | SAVE_GPR(13, r1) /* Save paca */ | |
636 | SAVE_8GPRS(14, r1) /* Save the non-volatiles */ | |
637 | SAVE_10GPRS(22, r1) /* ditto */ | |
638 | ||
639 | mfcr r4 | |
640 | std r4,_CCR(r1) | |
641 | mfctr r5 | |
642 | std r5,_CTR(r1) | |
643 | mfspr r6,SPRN_XER | |
644 | std r6,_XER(r1) | |
645 | mfdar r7 | |
646 | std r7,_DAR(r1) | |
647 | mfdsisr r8 | |
648 | std r8,_DSISR(r1) | |
649 | mfsrr0 r9 | |
650 | std r9,_SRR0(r1) | |
651 | mfsrr1 r10 | |
652 | std r10,_SRR1(r1) | |
653 | ||
654 | /* There is no way it is acceptable to get here with interrupts enabled, | |
655 | * check it with the asm equivalent of WARN_ON | |
656 | */ | |
657 | mfmsr r6 | |
658 | andi. r0,r6,MSR_EE | |
659 | 1: tdnei r0,0 | |
660 | .section __bug_table,"a" | |
661 | .llong 1b,__LINE__ + 0x1000000, 1f, 2f | |
662 | .previous | |
663 | .section .rodata,"a" | |
664 | 1: .asciz __FILE__ | |
665 | 2: .asciz "enter_rtas" | |
666 | .previous | |
667 | ||
668 | /* Unfortunately, the stack pointer and the MSR are also clobbered, | |
669 | * so they are saved in the PACA which allows us to restore | |
670 | * our original state after RTAS returns. | |
671 | */ | |
672 | std r1,PACAR1(r13) | |
673 | std r6,PACASAVEDMSR(r13) | |
674 | ||
675 | /* Setup our real return addr */ | |
676 | SET_REG_TO_LABEL(r4,.rtas_return_loc) | |
677 | SET_REG_TO_CONST(r9,KERNELBASE) | |
678 | sub r4,r4,r9 | |
679 | mtlr r4 | |
680 | ||
681 | li r0,0 | |
682 | ori r0,r0,MSR_EE|MSR_SE|MSR_BE|MSR_RI | |
683 | andc r0,r6,r0 | |
684 | ||
685 | li r9,1 | |
686 | rldicr r9,r9,MSR_SF_LG,(63-MSR_SF_LG) | |
687 | ori r9,r9,MSR_IR|MSR_DR|MSR_FE0|MSR_FE1|MSR_FP | |
688 | andc r6,r0,r9 | |
689 | ori r6,r6,MSR_RI | |
690 | sync /* disable interrupts so SRR0/1 */ | |
691 | mtmsrd r0 /* don't get trashed */ | |
692 | ||
693 | SET_REG_TO_LABEL(r4,rtas) | |
694 | ld r5,RTASENTRY(r4) /* get the rtas->entry value */ | |
695 | ld r4,RTASBASE(r4) /* get the rtas->base value */ | |
696 | ||
697 | mtspr SPRN_SRR0,r5 | |
698 | mtspr SPRN_SRR1,r6 | |
699 | rfid | |
700 | b . /* prevent speculative execution */ | |
701 | ||
702 | _STATIC(rtas_return_loc) | |
703 | /* relocation is off at this point */ | |
704 | mfspr r4,SPRN_SPRG3 /* Get PACA */ | |
705 | SET_REG_TO_CONST(r5, KERNELBASE) | |
706 | sub r4,r4,r5 /* RELOC the PACA base pointer */ | |
707 | ||
708 | mfmsr r6 | |
709 | li r0,MSR_RI | |
710 | andc r6,r6,r0 | |
711 | sync | |
712 | mtmsrd r6 | |
713 | ||
714 | ld r1,PACAR1(r4) /* Restore our SP */ | |
715 | LOADADDR(r3,.rtas_restore_regs) | |
716 | ld r4,PACASAVEDMSR(r4) /* Restore our MSR */ | |
717 | ||
718 | mtspr SPRN_SRR0,r3 | |
719 | mtspr SPRN_SRR1,r4 | |
720 | rfid | |
721 | b . /* prevent speculative execution */ | |
722 | ||
723 | _STATIC(rtas_restore_regs) | |
724 | /* relocation is on at this point */ | |
725 | REST_GPR(2, r1) /* Restore the TOC */ | |
726 | REST_GPR(13, r1) /* Restore paca */ | |
727 | REST_8GPRS(14, r1) /* Restore the non-volatiles */ | |
728 | REST_10GPRS(22, r1) /* ditto */ | |
729 | ||
730 | mfspr r13,SPRN_SPRG3 | |
731 | ||
732 | ld r4,_CCR(r1) | |
733 | mtcr r4 | |
734 | ld r5,_CTR(r1) | |
735 | mtctr r5 | |
736 | ld r6,_XER(r1) | |
737 | mtspr SPRN_XER,r6 | |
738 | ld r7,_DAR(r1) | |
739 | mtdar r7 | |
740 | ld r8,_DSISR(r1) | |
741 | mtdsisr r8 | |
742 | ld r9,_SRR0(r1) | |
743 | mtsrr0 r9 | |
744 | ld r10,_SRR1(r1) | |
745 | mtsrr1 r10 | |
746 | ||
747 | addi r1,r1,RTAS_FRAME_SIZE /* Unstack our frame */ | |
748 | ld r0,16(r1) /* get return address */ | |
749 | ||
750 | mtlr r0 | |
751 | blr /* return to caller */ | |
752 | ||
753 | #endif /* CONFIG_PPC_RTAS */ | |
754 | ||
755 | #ifdef CONFIG_PPC_MULTIPLATFORM | |
756 | ||
757 | _GLOBAL(enter_prom) | |
758 | mflr r0 | |
759 | std r0,16(r1) | |
760 | stdu r1,-PROM_FRAME_SIZE(r1) /* Save SP and create stack space */ | |
761 | ||
762 | /* Because PROM is running in 32b mode, it clobbers the high order half | |
763 | * of all registers that it saves. We therefore save those registers | |
764 | * PROM might touch to the stack. (r0, r3-r13 are caller saved) | |
765 | */ | |
766 | SAVE_8GPRS(2, r1) | |
767 | SAVE_GPR(13, r1) | |
768 | SAVE_8GPRS(14, r1) | |
769 | SAVE_10GPRS(22, r1) | |
770 | mfcr r4 | |
771 | std r4,_CCR(r1) | |
772 | mfctr r5 | |
773 | std r5,_CTR(r1) | |
774 | mfspr r6,SPRN_XER | |
775 | std r6,_XER(r1) | |
776 | mfdar r7 | |
777 | std r7,_DAR(r1) | |
778 | mfdsisr r8 | |
779 | std r8,_DSISR(r1) | |
780 | mfsrr0 r9 | |
781 | std r9,_SRR0(r1) | |
782 | mfsrr1 r10 | |
783 | std r10,_SRR1(r1) | |
784 | mfmsr r11 | |
785 | std r11,_MSR(r1) | |
786 | ||
787 | /* Get the PROM entrypoint */ | |
788 | ld r0,GPR4(r1) | |
789 | mtlr r0 | |
790 | ||
791 | /* Switch MSR to 32 bits mode | |
792 | */ | |
793 | mfmsr r11 | |
794 | li r12,1 | |
795 | rldicr r12,r12,MSR_SF_LG,(63-MSR_SF_LG) | |
796 | andc r11,r11,r12 | |
797 | li r12,1 | |
798 | rldicr r12,r12,MSR_ISF_LG,(63-MSR_ISF_LG) | |
799 | andc r11,r11,r12 | |
800 | mtmsrd r11 | |
801 | isync | |
802 | ||
803 | /* Restore arguments & enter PROM here... */ | |
804 | ld r3,GPR3(r1) | |
805 | blrl | |
806 | ||
807 | /* Just make sure that r1 top 32 bits didn't get | |
808 | * corrupt by OF | |
809 | */ | |
810 | rldicl r1,r1,0,32 | |
811 | ||
812 | /* Restore the MSR (back to 64 bits) */ | |
813 | ld r0,_MSR(r1) | |
814 | mtmsrd r0 | |
815 | isync | |
816 | ||
817 | /* Restore other registers */ | |
818 | REST_GPR(2, r1) | |
819 | REST_GPR(13, r1) | |
820 | REST_8GPRS(14, r1) | |
821 | REST_10GPRS(22, r1) | |
822 | ld r4,_CCR(r1) | |
823 | mtcr r4 | |
824 | ld r5,_CTR(r1) | |
825 | mtctr r5 | |
826 | ld r6,_XER(r1) | |
827 | mtspr SPRN_XER,r6 | |
828 | ld r7,_DAR(r1) | |
829 | mtdar r7 | |
830 | ld r8,_DSISR(r1) | |
831 | mtdsisr r8 | |
832 | ld r9,_SRR0(r1) | |
833 | mtsrr0 r9 | |
834 | ld r10,_SRR1(r1) | |
835 | mtsrr1 r10 | |
836 | ||
837 | addi r1,r1,PROM_FRAME_SIZE | |
838 | ld r0,16(r1) | |
839 | mtlr r0 | |
840 | blr | |
841 | ||
842 | #endif /* CONFIG_PPC_MULTIPLATFORM */ |