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2874c5fd | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
9994a338 PM |
2 | /* |
3 | * PowerPC version | |
4 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) | |
5 | * Rewritten by Cort Dougan (cort@fsmlabs.com) for PReP | |
6 | * Copyright (C) 1996 Cort Dougan <cort@fsmlabs.com> | |
7 | * Adapted for Power Macintosh by Paul Mackerras. | |
8 | * Low-level exception handlers and MMU support | |
9 | * rewritten by Paul Mackerras. | |
10 | * Copyright (C) 1996 Paul Mackerras. | |
11 | * MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net). | |
12 | * | |
13 | * This file contains the system call entry code, context switch | |
14 | * code, and exception/interrupt return code for PowerPC. | |
9994a338 PM |
15 | */ |
16 | ||
9994a338 | 17 | #include <linux/errno.h> |
c3525940 | 18 | #include <linux/err.h> |
9994a338 PM |
19 | #include <linux/sys.h> |
20 | #include <linux/threads.h> | |
21 | #include <asm/reg.h> | |
22 | #include <asm/page.h> | |
23 | #include <asm/mmu.h> | |
24 | #include <asm/cputable.h> | |
25 | #include <asm/thread_info.h> | |
26 | #include <asm/ppc_asm.h> | |
27 | #include <asm/asm-offsets.h> | |
28 | #include <asm/unistd.h> | |
46f52210 | 29 | #include <asm/ptrace.h> |
9445aa1a | 30 | #include <asm/export.h> |
36a7eeaf | 31 | #include <asm/asm-405.h> |
2c86cd18 | 32 | #include <asm/feature-fixups.h> |
c28218d4 | 33 | #include <asm/barrier.h> |
e2fb9f54 | 34 | #include <asm/kup.h> |
40530db7 | 35 | #include <asm/bug.h> |
9994a338 | 36 | |
37737a2a | 37 | #include "head_32.h" |
9994a338 | 38 | |
0eb0d2e7 CL |
39 | /* |
40 | * Align to 4k in order to ensure that all functions modyfing srr0/srr1 | |
41 | * fit into one page in order to not encounter a TLB miss between the | |
42 | * modification of srr0/srr1 and the associated rfi. | |
43 | */ | |
44 | .align 12 | |
45 | ||
9994a338 | 46 | #ifdef CONFIG_BOOKE |
9994a338 PM |
47 | .globl mcheck_transfer_to_handler |
48 | mcheck_transfer_to_handler: | |
fca622c5 KG |
49 | mfspr r0,SPRN_DSRR0 |
50 | stw r0,_DSRR0(r11) | |
51 | mfspr r0,SPRN_DSRR1 | |
52 | stw r0,_DSRR1(r11) | |
53 | /* fall through */ | |
9994a338 PM |
54 | |
55 | .globl debug_transfer_to_handler | |
56 | debug_transfer_to_handler: | |
fca622c5 KG |
57 | mfspr r0,SPRN_CSRR0 |
58 | stw r0,_CSRR0(r11) | |
59 | mfspr r0,SPRN_CSRR1 | |
60 | stw r0,_CSRR1(r11) | |
61 | /* fall through */ | |
9994a338 PM |
62 | |
63 | .globl crit_transfer_to_handler | |
64 | crit_transfer_to_handler: | |
70fe3af8 | 65 | #ifdef CONFIG_PPC_BOOK3E_MMU |
fca622c5 KG |
66 | mfspr r0,SPRN_MAS0 |
67 | stw r0,MAS0(r11) | |
68 | mfspr r0,SPRN_MAS1 | |
69 | stw r0,MAS1(r11) | |
70 | mfspr r0,SPRN_MAS2 | |
71 | stw r0,MAS2(r11) | |
72 | mfspr r0,SPRN_MAS3 | |
73 | stw r0,MAS3(r11) | |
74 | mfspr r0,SPRN_MAS6 | |
75 | stw r0,MAS6(r11) | |
76 | #ifdef CONFIG_PHYS_64BIT | |
77 | mfspr r0,SPRN_MAS7 | |
78 | stw r0,MAS7(r11) | |
79 | #endif /* CONFIG_PHYS_64BIT */ | |
70fe3af8 | 80 | #endif /* CONFIG_PPC_BOOK3E_MMU */ |
fca622c5 KG |
81 | #ifdef CONFIG_44x |
82 | mfspr r0,SPRN_MMUCR | |
83 | stw r0,MMUCR(r11) | |
84 | #endif | |
85 | mfspr r0,SPRN_SRR0 | |
86 | stw r0,_SRR0(r11) | |
87 | mfspr r0,SPRN_SRR1 | |
88 | stw r0,_SRR1(r11) | |
89 | ||
a7916a1d | 90 | /* set the stack limit to the current stack */ |
ee43eb78 | 91 | mfspr r8,SPRN_SPRG_THREAD |
fca622c5 KG |
92 | lwz r0,KSP_LIMIT(r8) |
93 | stw r0,SAVED_KSP_LIMIT(r11) | |
a7916a1d | 94 | rlwinm r0,r1,0,0,(31 - THREAD_SHIFT) |
fca622c5 | 95 | stw r0,KSP_LIMIT(r8) |
9994a338 PM |
96 | /* fall through */ |
97 | #endif | |
98 | ||
99 | #ifdef CONFIG_40x | |
100 | .globl crit_transfer_to_handler | |
101 | crit_transfer_to_handler: | |
102 | lwz r0,crit_r10@l(0) | |
103 | stw r0,GPR10(r11) | |
104 | lwz r0,crit_r11@l(0) | |
105 | stw r0,GPR11(r11) | |
fca622c5 KG |
106 | mfspr r0,SPRN_SRR0 |
107 | stw r0,crit_srr0@l(0) | |
108 | mfspr r0,SPRN_SRR1 | |
109 | stw r0,crit_srr1@l(0) | |
110 | ||
a7916a1d | 111 | /* set the stack limit to the current stack */ |
ee43eb78 | 112 | mfspr r8,SPRN_SPRG_THREAD |
fca622c5 KG |
113 | lwz r0,KSP_LIMIT(r8) |
114 | stw r0,saved_ksp_limit@l(0) | |
a7916a1d | 115 | rlwinm r0,r1,0,0,(31 - THREAD_SHIFT) |
fca622c5 | 116 | stw r0,KSP_LIMIT(r8) |
9994a338 PM |
117 | /* fall through */ |
118 | #endif | |
119 | ||
120 | /* | |
121 | * This code finishes saving the registers to the exception frame | |
122 | * and jumps to the appropriate handler for the exception, turning | |
123 | * on address translation. | |
124 | * Note that we rely on the caller having set cr0.eq iff the exception | |
125 | * occurred in kernel mode (i.e. MSR:PR = 0). | |
126 | */ | |
127 | .globl transfer_to_handler_full | |
128 | transfer_to_handler_full: | |
129 | SAVE_NVGPRS(r11) | |
130 | /* fall through */ | |
131 | ||
132 | .globl transfer_to_handler | |
133 | transfer_to_handler: | |
134 | stw r2,GPR2(r11) | |
135 | stw r12,_NIP(r11) | |
136 | stw r9,_MSR(r11) | |
137 | andi. r2,r9,MSR_PR | |
138 | mfctr r12 | |
139 | mfspr r2,SPRN_XER | |
140 | stw r12,_CTR(r11) | |
141 | stw r2,_XER(r11) | |
ee43eb78 | 142 | mfspr r12,SPRN_SPRG_THREAD |
9994a338 | 143 | beq 2f /* if from user, fix up THREAD.regs */ |
e2fb9f54 | 144 | addi r2, r12, -THREAD |
9994a338 PM |
145 | addi r11,r1,STACK_FRAME_OVERHEAD |
146 | stw r11,PT_REGS(r12) | |
147 | #if defined(CONFIG_40x) || defined(CONFIG_BOOKE) | |
148 | /* Check to see if the dbcr0 register is set up to debug. Use the | |
4eaddb4d | 149 | internal debug mode bit to do this. */ |
9994a338 | 150 | lwz r12,THREAD_DBCR0(r12) |
2325f0a0 | 151 | andis. r12,r12,DBCR0_IDM@h |
6b9166f0 | 152 | #endif |
f7354cca | 153 | ACCOUNT_CPU_USER_ENTRY(r2, r11, r12) |
31ed2b13 CL |
154 | #ifdef CONFIG_PPC_BOOK3S_32 |
155 | kuep_lock r11, r12 | |
156 | #endif | |
6b9166f0 | 157 | #if defined(CONFIG_40x) || defined(CONFIG_BOOKE) |
9994a338 PM |
158 | beq+ 3f |
159 | /* From user and task is ptraced - load up global dbcr0 */ | |
160 | li r12,-1 /* clear all pending debug events */ | |
161 | mtspr SPRN_DBSR,r12 | |
162 | lis r11,global_dbcr0@ha | |
163 | tophys(r11,r11) | |
164 | addi r11,r11,global_dbcr0@l | |
4eaddb4d | 165 | #ifdef CONFIG_SMP |
f7354cca | 166 | lwz r9,TASK_CPU(r2) |
4eaddb4d KG |
167 | slwi r9,r9,3 |
168 | add r11,r11,r9 | |
169 | #endif | |
9994a338 PM |
170 | lwz r12,0(r11) |
171 | mtspr SPRN_DBCR0,r12 | |
172 | lwz r12,4(r11) | |
173 | addi r12,r12,-1 | |
174 | stw r12,4(r11) | |
175 | #endif | |
c223c903 | 176 | |
9994a338 | 177 | b 3f |
f39224a8 | 178 | |
9994a338 PM |
179 | 2: /* if from kernel, check interrupted DOZE/NAP mode and |
180 | * check for stack overflow | |
181 | */ | |
e2fb9f54 CL |
182 | kuap_save_and_lock r11, r12, r9, r2, r0 |
183 | addi r2, r12, -THREAD | |
85218827 KG |
184 | lwz r9,KSP_LIMIT(r12) |
185 | cmplw r1,r9 /* if r1 <= ksp_limit */ | |
f39224a8 PM |
186 | ble- stack_ovf /* then the kernel stack overflowed */ |
187 | 5: | |
d7cceda9 | 188 | #if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500) |
f7354cca | 189 | lwz r12,TI_LOCAL_FLAGS(r2) |
f39224a8 PM |
190 | mtcrf 0x01,r12 |
191 | bt- 31-TLF_NAPPING,4f | |
a560643e | 192 | bt- 31-TLF_SLEEPING,7f |
d7cceda9 | 193 | #endif /* CONFIG_PPC_BOOK3S_32 || CONFIG_E500 */ |
9994a338 PM |
194 | .globl transfer_to_handler_cont |
195 | transfer_to_handler_cont: | |
9994a338 PM |
196 | 3: |
197 | mflr r9 | |
f7354cca | 198 | tovirt(r2, r2) /* set r2 to current */ |
9994a338 PM |
199 | lwz r11,0(r9) /* virtual address of handler */ |
200 | lwz r9,4(r9) /* where to go when done */ | |
cd99ddbe | 201 | #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) |
75b82472 CL |
202 | mtspr SPRN_NRI, r0 |
203 | #endif | |
5d38902c | 204 | #ifdef CONFIG_TRACE_IRQFLAGS |
40530db7 CL |
205 | /* |
206 | * When tracing IRQ state (lockdep) we enable the MMU before we call | |
207 | * the IRQ tracing functions as they might access vmalloc space or | |
208 | * perform IOs for console output. | |
209 | * | |
210 | * To speed up the syscall path where interrupts stay on, let's check | |
211 | * first if we are changing the MSR value at all. | |
212 | */ | |
213 | tophys(r12, r1) | |
214 | lwz r12,_MSR(r12) | |
40530db7 CL |
215 | andi. r12,r12,MSR_EE |
216 | bne 1f | |
217 | ||
218 | /* MSR isn't changing, just transition directly */ | |
219 | #endif | |
220 | mtspr SPRN_SRR0,r11 | |
221 | mtspr SPRN_SRR1,r10 | |
222 | mtlr r9 | |
223 | SYNC | |
224 | RFI /* jump to handler, enable MMU */ | |
225 | ||
226 | #ifdef CONFIG_TRACE_IRQFLAGS | |
227 | 1: /* MSR is changing, re-enable MMU so we can notify lockdep. We need to | |
228 | * keep interrupts disabled at this point otherwise we might risk | |
229 | * taking an interrupt before we tell lockdep they are enabled. | |
230 | */ | |
5d38902c BH |
231 | lis r12,reenable_mmu@h |
232 | ori r12,r12,reenable_mmu@l | |
40530db7 | 233 | LOAD_MSR_KERNEL(r0, MSR_KERNEL) |
5d38902c | 234 | mtspr SPRN_SRR0,r12 |
40530db7 | 235 | mtspr SPRN_SRR1,r0 |
5d38902c BH |
236 | SYNC |
237 | RFI | |
5d38902c | 238 | |
40530db7 | 239 | reenable_mmu: |
2cd76629 | 240 | /* |
d1865e71 | 241 | * We save a bunch of GPRs, |
08f1ec8a BH |
242 | * r3 can be different from GPR3(r1) at this point, r9 and r11 |
243 | * contains the old MSR and handler address respectively, | |
244 | * r4 & r5 can contain page fault arguments that need to be passed | |
245 | * along as well. r12, CCR, CTR, XER etc... are left clobbered as | |
246 | * they aren't useful past this point (aren't syscall arguments), | |
247 | * the rest is restored from the exception frame. | |
2cd76629 | 248 | */ |
40530db7 | 249 | |
08f1ec8a BH |
250 | stwu r1,-32(r1) |
251 | stw r9,8(r1) | |
252 | stw r11,12(r1) | |
253 | stw r3,16(r1) | |
254 | stw r4,20(r1) | |
255 | stw r5,24(r1) | |
40530db7 | 256 | |
40530db7 CL |
257 | /* If we are disabling interrupts (normal case), simply log it with |
258 | * lockdep | |
259 | */ | |
260 | 1: bl trace_hardirqs_off | |
261 | 2: lwz r5,24(r1) | |
08f1ec8a BH |
262 | lwz r4,20(r1) |
263 | lwz r3,16(r1) | |
264 | lwz r11,12(r1) | |
265 | lwz r9,8(r1) | |
266 | addi r1,r1,32 | |
5d38902c | 267 | lwz r0,GPR0(r1) |
5d38902c BH |
268 | lwz r6,GPR6(r1) |
269 | lwz r7,GPR7(r1) | |
270 | lwz r8,GPR8(r1) | |
40530db7 | 271 | mtctr r11 |
5d38902c BH |
272 | mtlr r9 |
273 | bctr /* jump to handler */ | |
5d38902c | 274 | #endif /* CONFIG_TRACE_IRQFLAGS */ |
9994a338 | 275 | |
d7cceda9 | 276 | #if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500) |
f39224a8 | 277 | 4: rlwinm r12,r12,0,~_TLF_NAPPING |
f7354cca | 278 | stw r12,TI_LOCAL_FLAGS(r2) |
fc4033b2 | 279 | b power_save_ppc32_restore |
a560643e PM |
280 | |
281 | 7: rlwinm r12,r12,0,~_TLF_SLEEPING | |
f7354cca | 282 | stw r12,TI_LOCAL_FLAGS(r2) |
a560643e PM |
283 | lwz r9,_MSR(r11) /* if sleeping, clear MSR.EE */ |
284 | rlwinm r9,r9,0,~MSR_EE | |
285 | lwz r12,_LINK(r11) /* and return to address in LR */ | |
e2fb9f54 | 286 | kuap_restore r11, r2, r3, r4, r5 |
a560643e | 287 | b fast_exception_return |
a0652fc9 PM |
288 | #endif |
289 | ||
9994a338 PM |
290 | /* |
291 | * On kernel stack overflow, load up an initial stack pointer | |
292 | * and call StackOverflow(regs), which should not return. | |
293 | */ | |
294 | stack_ovf: | |
295 | /* sometimes we use a statically-allocated stack, which is OK. */ | |
f39224a8 PM |
296 | lis r12,_end@h |
297 | ori r12,r12,_end@l | |
298 | cmplw r1,r12 | |
299 | ble 5b /* r1 <= &_end is OK */ | |
9994a338 PM |
300 | SAVE_NVGPRS(r11) |
301 | addi r3,r1,STACK_FRAME_OVERHEAD | |
302 | lis r1,init_thread_union@ha | |
303 | addi r1,r1,init_thread_union@l | |
304 | addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD | |
305 | lis r9,StackOverflow@ha | |
306 | addi r9,r9,StackOverflow@l | |
307 | LOAD_MSR_KERNEL(r10,MSR_KERNEL) | |
cd99ddbe | 308 | #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) |
75b82472 CL |
309 | mtspr SPRN_NRI, r0 |
310 | #endif | |
9994a338 PM |
311 | mtspr SPRN_SRR0,r9 |
312 | mtspr SPRN_SRR1,r10 | |
313 | SYNC | |
314 | RFI | |
315 | ||
b86fb888 CL |
316 | #ifdef CONFIG_TRACE_IRQFLAGS |
317 | trace_syscall_entry_irq_off: | |
318 | /* | |
319 | * Syscall shouldn't happen while interrupts are disabled, | |
320 | * so let's do a warning here. | |
321 | */ | |
322 | 0: trap | |
323 | EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING | |
324 | bl trace_hardirqs_on | |
325 | ||
326 | /* Now enable for real */ | |
327 | LOAD_MSR_KERNEL(r10, MSR_KERNEL | MSR_EE) | |
328 | mtmsr r10 | |
329 | ||
330 | REST_GPR(0, r1) | |
331 | REST_4GPRS(3, r1) | |
332 | REST_2GPRS(7, r1) | |
333 | b DoSyscall | |
334 | #endif /* CONFIG_TRACE_IRQFLAGS */ | |
335 | ||
336 | .globl transfer_to_syscall | |
337 | transfer_to_syscall: | |
338 | #ifdef CONFIG_TRACE_IRQFLAGS | |
339 | andi. r12,r9,MSR_EE | |
340 | beq- trace_syscall_entry_irq_off | |
341 | #endif /* CONFIG_TRACE_IRQFLAGS */ | |
b86fb888 | 342 | |
9994a338 PM |
343 | /* |
344 | * Handle a system call. | |
345 | */ | |
346 | .stabs "arch/powerpc/kernel/",N_SO,0,0,0f | |
347 | .stabs "entry_32.S",N_SO,0,0,0f | |
348 | 0: | |
349 | ||
350 | _GLOBAL(DoSyscall) | |
9994a338 PM |
351 | stw r3,ORIG_GPR3(r1) |
352 | li r12,0 | |
353 | stw r12,RESULT(r1) | |
5d38902c | 354 | #ifdef CONFIG_TRACE_IRQFLAGS |
40530db7 | 355 | /* Make sure interrupts are enabled */ |
5d38902c BH |
356 | mfmsr r11 |
357 | andi. r12,r11,MSR_EE | |
40530db7 CL |
358 | /* We came in with interrupts disabled, we WARN and mark them enabled |
359 | * for lockdep now */ | |
360 | 0: tweqi r12, 0 | |
361 | EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING | |
5d38902c | 362 | #endif /* CONFIG_TRACE_IRQFLAGS */ |
f7354cca | 363 | lwz r11,TI_FLAGS(r2) |
10ea8343 | 364 | andi. r11,r11,_TIF_SYSCALL_DOTRACE |
9994a338 PM |
365 | bne- syscall_dotrace |
366 | syscall_dotrace_cont: | |
367 | cmplwi 0,r0,NR_syscalls | |
368 | lis r10,sys_call_table@h | |
369 | ori r10,r10,sys_call_table@l | |
370 | slwi r0,r0,2 | |
371 | bge- 66f | |
c28218d4 DC |
372 | |
373 | barrier_nospec_asm | |
374 | /* | |
375 | * Prevent the load of the handler below (based on the user-passed | |
376 | * system call number) being speculatively executed until the test | |
377 | * against NR_syscalls and branch to .66f above has | |
378 | * committed. | |
379 | */ | |
380 | ||
9994a338 PM |
381 | lwzx r10,r10,r0 /* Fetch system call handler [ptr] */ |
382 | mtlr r10 | |
383 | addi r9,r1,STACK_FRAME_OVERHEAD | |
384 | PPC440EP_ERR42 | |
385 | blrl /* Call handler */ | |
386 | .globl ret_from_syscall | |
387 | ret_from_syscall: | |
6f37be4b BF |
388 | #ifdef CONFIG_DEBUG_RSEQ |
389 | /* Check whether the syscall is issued inside a restartable sequence */ | |
390 | stw r3,GPR3(r1) | |
391 | addi r3,r1,STACK_FRAME_OVERHEAD | |
392 | bl rseq_syscall | |
393 | lwz r3,GPR3(r1) | |
394 | #endif | |
9994a338 | 395 | mr r6,r3 |
9994a338 | 396 | /* disable interrupts so current_thread_info()->flags can't change */ |
401d1f02 | 397 | LOAD_MSR_KERNEL(r10,MSR_KERNEL) /* doesn't include MSR_EE */ |
5d38902c | 398 | /* Note: We don't bother telling lockdep about it */ |
9994a338 PM |
399 | SYNC |
400 | MTMSRD(r10) | |
f7354cca | 401 | lwz r9,TI_FLAGS(r2) |
c3525940 | 402 | li r8,-MAX_ERRNO |
10ea8343 | 403 | andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK) |
9994a338 | 404 | bne- syscall_exit_work |
401d1f02 DW |
405 | cmplw 0,r3,r8 |
406 | blt+ syscall_exit_cont | |
407 | lwz r11,_CCR(r1) /* Load CR */ | |
408 | neg r3,r3 | |
409 | oris r11,r11,0x1000 /* Set SO bit in CR */ | |
410 | stw r11,_CCR(r1) | |
9994a338 | 411 | syscall_exit_cont: |
5d38902c BH |
412 | lwz r8,_MSR(r1) |
413 | #ifdef CONFIG_TRACE_IRQFLAGS | |
414 | /* If we are going to return from the syscall with interrupts | |
40530db7 | 415 | * off, we trace that here. It shouldn't normally happen. |
5d38902c BH |
416 | */ |
417 | andi. r10,r8,MSR_EE | |
418 | bne+ 1f | |
419 | stw r3,GPR3(r1) | |
420 | bl trace_hardirqs_off | |
421 | lwz r3,GPR3(r1) | |
422 | 1: | |
423 | #endif /* CONFIG_TRACE_IRQFLAGS */ | |
9994a338 | 424 | #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) |
4eaddb4d KG |
425 | /* If the process has its own DBCR0 value, load it up. The internal |
426 | debug mode bit tells us that dbcr0 should be loaded. */ | |
9994a338 | 427 | lwz r0,THREAD+THREAD_DBCR0(r2) |
2325f0a0 | 428 | andis. r10,r0,DBCR0_IDM@h |
9994a338 PM |
429 | bnel- load_dbcr0 |
430 | #endif | |
b98ac05d | 431 | #ifdef CONFIG_44x |
e7f75ad0 | 432 | BEGIN_MMU_FTR_SECTION |
b98ac05d BH |
433 | lis r4,icache_44x_need_flush@ha |
434 | lwz r5,icache_44x_need_flush@l(r4) | |
435 | cmplwi cr0,r5,0 | |
436 | bne- 2f | |
437 | 1: | |
e7f75ad0 | 438 | END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_47x) |
b98ac05d | 439 | #endif /* CONFIG_44x */ |
b64f87c1 BB |
440 | BEGIN_FTR_SECTION |
441 | lwarx r7,0,r1 | |
442 | END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX) | |
9994a338 | 443 | stwcx. r0,0,r1 /* to clear the reservation */ |
f7354cca | 444 | ACCOUNT_CPU_USER_EXIT(r2, r5, r7) |
31ed2b13 CL |
445 | #ifdef CONFIG_PPC_BOOK3S_32 |
446 | kuep_unlock r5, r7 | |
447 | #endif | |
e2fb9f54 | 448 | kuap_check r2, r4 |
9994a338 PM |
449 | lwz r4,_LINK(r1) |
450 | lwz r5,_CCR(r1) | |
451 | mtlr r4 | |
452 | mtcr r5 | |
453 | lwz r7,_NIP(r1) | |
9994a338 PM |
454 | lwz r2,GPR2(r1) |
455 | lwz r1,GPR1(r1) | |
cd99ddbe | 456 | #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) |
75b82472 CL |
457 | mtspr SPRN_NRI, r0 |
458 | #endif | |
9994a338 PM |
459 | mtspr SPRN_SRR0,r7 |
460 | mtspr SPRN_SRR1,r8 | |
461 | SYNC | |
462 | RFI | |
b98ac05d BH |
463 | #ifdef CONFIG_44x |
464 | 2: li r7,0 | |
465 | iccci r0,r0 | |
466 | stw r7,icache_44x_need_flush@l(r4) | |
467 | b 1b | |
468 | #endif /* CONFIG_44x */ | |
9994a338 PM |
469 | |
470 | 66: li r3,-ENOSYS | |
471 | b ret_from_syscall | |
472 | ||
473 | .globl ret_from_fork | |
474 | ret_from_fork: | |
475 | REST_NVGPRS(r1) | |
476 | bl schedule_tail | |
477 | li r3,0 | |
478 | b ret_from_syscall | |
479 | ||
58254e10 AV |
480 | .globl ret_from_kernel_thread |
481 | ret_from_kernel_thread: | |
482 | REST_NVGPRS(r1) | |
483 | bl schedule_tail | |
484 | mtlr r14 | |
485 | mr r3,r15 | |
486 | PPC440EP_ERR42 | |
487 | blrl | |
488 | li r3,0 | |
be6abfa7 | 489 | b ret_from_syscall |
9994a338 PM |
490 | |
491 | /* Traced system call support */ | |
492 | syscall_dotrace: | |
493 | SAVE_NVGPRS(r1) | |
494 | li r0,0xc00 | |
d73e0c99 | 495 | stw r0,_TRAP(r1) |
9994a338 PM |
496 | addi r3,r1,STACK_FRAME_OVERHEAD |
497 | bl do_syscall_trace_enter | |
4f72c427 RM |
498 | /* |
499 | * Restore argument registers possibly just changed. | |
500 | * We use the return value of do_syscall_trace_enter | |
501 | * for call number to look up in the table (r0). | |
502 | */ | |
503 | mr r0,r3 | |
9994a338 PM |
504 | lwz r3,GPR3(r1) |
505 | lwz r4,GPR4(r1) | |
506 | lwz r5,GPR5(r1) | |
507 | lwz r6,GPR6(r1) | |
508 | lwz r7,GPR7(r1) | |
509 | lwz r8,GPR8(r1) | |
510 | REST_NVGPRS(r1) | |
d3837414 ME |
511 | |
512 | cmplwi r0,NR_syscalls | |
513 | /* Return code is already in r3 thanks to do_syscall_trace_enter() */ | |
514 | bge- ret_from_syscall | |
9994a338 PM |
515 | b syscall_dotrace_cont |
516 | ||
517 | syscall_exit_work: | |
401d1f02 | 518 | andi. r0,r9,_TIF_RESTOREALL |
1bd79336 PM |
519 | beq+ 0f |
520 | REST_NVGPRS(r1) | |
521 | b 2f | |
522 | 0: cmplw 0,r3,r8 | |
401d1f02 DW |
523 | blt+ 1f |
524 | andi. r0,r9,_TIF_NOERROR | |
525 | bne- 1f | |
526 | lwz r11,_CCR(r1) /* Load CR */ | |
527 | neg r3,r3 | |
528 | oris r11,r11,0x1000 /* Set SO bit in CR */ | |
529 | stw r11,_CCR(r1) | |
530 | ||
531 | 1: stw r6,RESULT(r1) /* Save result */ | |
9994a338 | 532 | stw r3,GPR3(r1) /* Update return value */ |
401d1f02 DW |
533 | 2: andi. r0,r9,(_TIF_PERSYSCALL_MASK) |
534 | beq 4f | |
535 | ||
1bd79336 | 536 | /* Clear per-syscall TIF flags if any are set. */ |
401d1f02 DW |
537 | |
538 | li r11,_TIF_PERSYSCALL_MASK | |
f7354cca | 539 | addi r12,r2,TI_FLAGS |
401d1f02 DW |
540 | 3: lwarx r8,0,r12 |
541 | andc r8,r8,r11 | |
542 | #ifdef CONFIG_IBM405_ERR77 | |
543 | dcbt 0,r12 | |
544 | #endif | |
545 | stwcx. r8,0,r12 | |
546 | bne- 3b | |
401d1f02 DW |
547 | |
548 | 4: /* Anything which requires enabling interrupts? */ | |
10ea8343 | 549 | andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP) |
1bd79336 PM |
550 | beq ret_from_except |
551 | ||
5d38902c BH |
552 | /* Re-enable interrupts. There is no need to trace that with |
553 | * lockdep as we are supposed to have IRQs on at this point | |
554 | */ | |
1bd79336 PM |
555 | ori r10,r10,MSR_EE |
556 | SYNC | |
557 | MTMSRD(r10) | |
401d1f02 DW |
558 | |
559 | /* Save NVGPRS if they're not saved already */ | |
d73e0c99 | 560 | lwz r4,_TRAP(r1) |
9994a338 | 561 | andi. r4,r4,1 |
401d1f02 | 562 | beq 5f |
9994a338 PM |
563 | SAVE_NVGPRS(r1) |
564 | li r4,0xc00 | |
d73e0c99 | 565 | stw r4,_TRAP(r1) |
1bd79336 | 566 | 5: |
9994a338 PM |
567 | addi r3,r1,STACK_FRAME_OVERHEAD |
568 | bl do_syscall_trace_leave | |
1bd79336 | 569 | b ret_from_except_full |
9994a338 | 570 | |
9994a338 | 571 | /* |
401d1f02 DW |
572 | * The fork/clone functions need to copy the full register set into |
573 | * the child process. Therefore we need to save all the nonvolatile | |
574 | * registers (r13 - r31) before calling the C code. | |
9994a338 | 575 | */ |
9994a338 PM |
576 | .globl ppc_fork |
577 | ppc_fork: | |
578 | SAVE_NVGPRS(r1) | |
d73e0c99 | 579 | lwz r0,_TRAP(r1) |
9994a338 | 580 | rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ |
d73e0c99 | 581 | stw r0,_TRAP(r1) /* register set saved */ |
9994a338 PM |
582 | b sys_fork |
583 | ||
584 | .globl ppc_vfork | |
585 | ppc_vfork: | |
586 | SAVE_NVGPRS(r1) | |
d73e0c99 | 587 | lwz r0,_TRAP(r1) |
9994a338 | 588 | rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ |
d73e0c99 | 589 | stw r0,_TRAP(r1) /* register set saved */ |
9994a338 PM |
590 | b sys_vfork |
591 | ||
592 | .globl ppc_clone | |
593 | ppc_clone: | |
594 | SAVE_NVGPRS(r1) | |
d73e0c99 | 595 | lwz r0,_TRAP(r1) |
9994a338 | 596 | rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ |
d73e0c99 | 597 | stw r0,_TRAP(r1) /* register set saved */ |
9994a338 PM |
598 | b sys_clone |
599 | ||
1bd79336 PM |
600 | .globl ppc_swapcontext |
601 | ppc_swapcontext: | |
602 | SAVE_NVGPRS(r1) | |
603 | lwz r0,_TRAP(r1) | |
604 | rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ | |
605 | stw r0,_TRAP(r1) /* register set saved */ | |
606 | b sys_swapcontext | |
607 | ||
9994a338 PM |
608 | /* |
609 | * Top-level page fault handling. | |
610 | * This is in assembler because if do_page_fault tells us that | |
611 | * it is a bad kernel page fault, we want to save the non-volatile | |
612 | * registers before calling bad_page_fault. | |
613 | */ | |
614 | .globl handle_page_fault | |
615 | handle_page_fault: | |
616 | stw r4,_DAR(r1) | |
617 | addi r3,r1,STACK_FRAME_OVERHEAD | |
d7cceda9 | 618 | #ifdef CONFIG_PPC_BOOK3S_32 |
64d0a506 | 619 | andis. r0,r5,DSISR_DABRMATCH@h |
d300627c | 620 | bne- handle_dabr_fault |
d300627c | 621 | #endif |
64d0a506 | 622 | bl do_page_fault |
9994a338 PM |
623 | cmpwi r3,0 |
624 | beq+ ret_from_except | |
625 | SAVE_NVGPRS(r1) | |
d73e0c99 | 626 | lwz r0,_TRAP(r1) |
9994a338 | 627 | clrrwi r0,r0,1 |
d73e0c99 | 628 | stw r0,_TRAP(r1) |
9994a338 PM |
629 | mr r5,r3 |
630 | addi r3,r1,STACK_FRAME_OVERHEAD | |
631 | lwz r4,_DAR(r1) | |
632 | bl bad_page_fault | |
633 | b ret_from_except_full | |
634 | ||
d7cceda9 | 635 | #ifdef CONFIG_PPC_BOOK3S_32 |
d300627c BH |
636 | /* We have a data breakpoint exception - handle it */ |
637 | handle_dabr_fault: | |
638 | SAVE_NVGPRS(r1) | |
639 | lwz r0,_TRAP(r1) | |
640 | clrrwi r0,r0,1 | |
641 | stw r0,_TRAP(r1) | |
642 | bl do_break | |
643 | b ret_from_except_full | |
644 | #endif | |
645 | ||
9994a338 PM |
646 | /* |
647 | * This routine switches between two different tasks. The process | |
648 | * state of one is saved on its kernel stack. Then the state | |
649 | * of the other is restored from its kernel stack. The memory | |
650 | * management hardware is updated to the second process's state. | |
651 | * Finally, we can return to the second process. | |
652 | * On entry, r3 points to the THREAD for the current task, r4 | |
653 | * points to the THREAD for the new task. | |
654 | * | |
655 | * This routine is always called with interrupts disabled. | |
656 | * | |
657 | * Note: there are two ways to get to the "going out" portion | |
658 | * of this code; either by coming in via the entry (_switch) | |
659 | * or via "fork" which must set up an environment equivalent | |
660 | * to the "_switch" path. If you change this , you'll have to | |
661 | * change the fork code also. | |
662 | * | |
663 | * The code which creates the new task context is in 'copy_thread' | |
664 | * in arch/ppc/kernel/process.c | |
665 | */ | |
666 | _GLOBAL(_switch) | |
667 | stwu r1,-INT_FRAME_SIZE(r1) | |
668 | mflr r0 | |
669 | stw r0,INT_FRAME_SIZE+4(r1) | |
670 | /* r3-r12 are caller saved -- Cort */ | |
671 | SAVE_NVGPRS(r1) | |
672 | stw r0,_NIP(r1) /* Return to switch caller */ | |
673 | mfmsr r11 | |
674 | li r0,MSR_FP /* Disable floating-point */ | |
675 | #ifdef CONFIG_ALTIVEC | |
676 | BEGIN_FTR_SECTION | |
677 | oris r0,r0,MSR_VEC@h /* Disable altivec */ | |
678 | mfspr r12,SPRN_VRSAVE /* save vrsave register value */ | |
679 | stw r12,THREAD+THREAD_VRSAVE(r2) | |
680 | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | |
681 | #endif /* CONFIG_ALTIVEC */ | |
682 | #ifdef CONFIG_SPE | |
5e14d21e | 683 | BEGIN_FTR_SECTION |
9994a338 PM |
684 | oris r0,r0,MSR_SPE@h /* Disable SPE */ |
685 | mfspr r12,SPRN_SPEFSCR /* save spefscr register value */ | |
686 | stw r12,THREAD+THREAD_SPEFSCR(r2) | |
5e14d21e | 687 | END_FTR_SECTION_IFSET(CPU_FTR_SPE) |
9994a338 PM |
688 | #endif /* CONFIG_SPE */ |
689 | and. r0,r0,r11 /* FP or altivec or SPE enabled? */ | |
690 | beq+ 1f | |
691 | andc r11,r11,r0 | |
692 | MTMSRD(r11) | |
693 | isync | |
694 | 1: stw r11,_MSR(r1) | |
695 | mfcr r10 | |
696 | stw r10,_CCR(r1) | |
697 | stw r1,KSP(r3) /* Set old stack pointer */ | |
698 | ||
e2fb9f54 | 699 | kuap_check r2, r4 |
9994a338 PM |
700 | #ifdef CONFIG_SMP |
701 | /* We need a sync somewhere here to make sure that if the | |
702 | * previous task gets rescheduled on another CPU, it sees all | |
703 | * stores it has performed on this one. | |
704 | */ | |
705 | sync | |
706 | #endif /* CONFIG_SMP */ | |
707 | ||
708 | tophys(r0,r4) | |
ee43eb78 | 709 | mtspr SPRN_SPRG_THREAD,r0 /* Update current THREAD phys addr */ |
9994a338 PM |
710 | lwz r1,KSP(r4) /* Load new stack pointer */ |
711 | ||
712 | /* save the old current 'last' for return value */ | |
713 | mr r3,r2 | |
714 | addi r2,r4,-THREAD /* Update current */ | |
715 | ||
716 | #ifdef CONFIG_ALTIVEC | |
717 | BEGIN_FTR_SECTION | |
718 | lwz r0,THREAD+THREAD_VRSAVE(r2) | |
719 | mtspr SPRN_VRSAVE,r0 /* if G4, restore VRSAVE reg */ | |
720 | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | |
721 | #endif /* CONFIG_ALTIVEC */ | |
722 | #ifdef CONFIG_SPE | |
5e14d21e | 723 | BEGIN_FTR_SECTION |
9994a338 PM |
724 | lwz r0,THREAD+THREAD_SPEFSCR(r2) |
725 | mtspr SPRN_SPEFSCR,r0 /* restore SPEFSCR reg */ | |
5e14d21e | 726 | END_FTR_SECTION_IFSET(CPU_FTR_SPE) |
9994a338 | 727 | #endif /* CONFIG_SPE */ |
f2574030 | 728 | |
9994a338 PM |
729 | lwz r0,_CCR(r1) |
730 | mtcrf 0xFF,r0 | |
731 | /* r3-r12 are destroyed -- Cort */ | |
732 | REST_NVGPRS(r1) | |
733 | ||
734 | lwz r4,_NIP(r1) /* Return to _switch caller in new task */ | |
735 | mtlr r4 | |
736 | addi r1,r1,INT_FRAME_SIZE | |
737 | blr | |
738 | ||
739 | .globl fast_exception_return | |
740 | fast_exception_return: | |
741 | #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) | |
742 | andi. r10,r9,MSR_RI /* check for recoverable interrupt */ | |
743 | beq 1f /* if not, we've got problems */ | |
744 | #endif | |
745 | ||
746 | 2: REST_4GPRS(3, r11) | |
747 | lwz r10,_CCR(r11) | |
748 | REST_GPR(1, r11) | |
749 | mtcr r10 | |
750 | lwz r10,_LINK(r11) | |
751 | mtlr r10 | |
9580b71b CL |
752 | /* Clear the exception_marker on the stack to avoid confusing stacktrace */ |
753 | li r10, 0 | |
754 | stw r10, 8(r11) | |
9994a338 | 755 | REST_GPR(10, r11) |
cd99ddbe | 756 | #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) |
75b82472 CL |
757 | mtspr SPRN_NRI, r0 |
758 | #endif | |
9994a338 PM |
759 | mtspr SPRN_SRR1,r9 |
760 | mtspr SPRN_SRR0,r12 | |
761 | REST_GPR(9, r11) | |
762 | REST_GPR(12, r11) | |
763 | lwz r11,GPR11(r11) | |
764 | SYNC | |
765 | RFI | |
766 | ||
767 | #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) | |
768 | /* check if the exception happened in a restartable section */ | |
769 | 1: lis r3,exc_exit_restart_end@ha | |
770 | addi r3,r3,exc_exit_restart_end@l | |
771 | cmplw r12,r3 | |
772 | bge 3f | |
773 | lis r4,exc_exit_restart@ha | |
774 | addi r4,r4,exc_exit_restart@l | |
775 | cmplw r12,r4 | |
776 | blt 3f | |
777 | lis r3,fee_restarts@ha | |
778 | tophys(r3,r3) | |
779 | lwz r5,fee_restarts@l(r3) | |
780 | addi r5,r5,1 | |
781 | stw r5,fee_restarts@l(r3) | |
782 | mr r12,r4 /* restart at exc_exit_restart */ | |
783 | b 2b | |
784 | ||
991eb43a KG |
785 | .section .bss |
786 | .align 2 | |
787 | fee_restarts: | |
788 | .space 4 | |
789 | .previous | |
9994a338 PM |
790 | |
791 | /* aargh, a nonrecoverable interrupt, panic */ | |
792 | /* aargh, we don't know which trap this is */ | |
793 | /* but the 601 doesn't implement the RI bit, so assume it's OK */ | |
794 | 3: | |
795 | BEGIN_FTR_SECTION | |
796 | b 2b | |
797 | END_FTR_SECTION_IFSET(CPU_FTR_601) | |
798 | li r10,-1 | |
d73e0c99 | 799 | stw r10,_TRAP(r11) |
9994a338 PM |
800 | addi r3,r1,STACK_FRAME_OVERHEAD |
801 | lis r10,MSR_KERNEL@h | |
802 | ori r10,r10,MSR_KERNEL@l | |
803 | bl transfer_to_handler_full | |
51423a9c | 804 | .long unrecoverable_exception |
9994a338 PM |
805 | .long ret_from_except |
806 | #endif | |
807 | ||
9994a338 PM |
808 | .globl ret_from_except_full |
809 | ret_from_except_full: | |
810 | REST_NVGPRS(r1) | |
811 | /* fall through */ | |
812 | ||
813 | .globl ret_from_except | |
814 | ret_from_except: | |
815 | /* Hard-disable interrupts so that current_thread_info()->flags | |
816 | * can't change between when we test it and when we return | |
817 | * from the interrupt. */ | |
5d38902c | 818 | /* Note: We don't bother telling lockdep about it */ |
9994a338 PM |
819 | LOAD_MSR_KERNEL(r10,MSR_KERNEL) |
820 | SYNC /* Some chip revs have problems here... */ | |
821 | MTMSRD(r10) /* disable interrupts */ | |
822 | ||
823 | lwz r3,_MSR(r1) /* Returning to user mode? */ | |
824 | andi. r0,r3,MSR_PR | |
825 | beq resume_kernel | |
826 | ||
827 | user_exc_return: /* r10 contains MSR_KERNEL here */ | |
828 | /* Check current_thread_info()->flags */ | |
f7354cca | 829 | lwz r9,TI_FLAGS(r2) |
7a10174e | 830 | andi. r0,r9,_TIF_USER_WORK_MASK |
9994a338 PM |
831 | bne do_work |
832 | ||
833 | restore_user: | |
834 | #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) | |
4eaddb4d KG |
835 | /* Check whether this process has its own DBCR0 value. The internal |
836 | debug mode bit tells us that dbcr0 should be loaded. */ | |
9994a338 | 837 | lwz r0,THREAD+THREAD_DBCR0(r2) |
2325f0a0 | 838 | andis. r10,r0,DBCR0_IDM@h |
9994a338 PM |
839 | bnel- load_dbcr0 |
840 | #endif | |
f7354cca | 841 | ACCOUNT_CPU_USER_EXIT(r2, r10, r11) |
31ed2b13 CL |
842 | #ifdef CONFIG_PPC_BOOK3S_32 |
843 | kuep_unlock r10, r11 | |
844 | #endif | |
9994a338 | 845 | |
9994a338 PM |
846 | b restore |
847 | ||
848 | /* N.B. the only way to get here is from the beq following ret_from_except. */ | |
849 | resume_kernel: | |
a9c4e541 | 850 | /* check current_thread_info, _TIF_EMULATE_STACK_STORE */ |
f7354cca | 851 | lwz r8,TI_FLAGS(r2) |
f7b33677 | 852 | andis. r0,r8,_TIF_EMULATE_STACK_STORE@h |
a9c4e541 TC |
853 | beq+ 1f |
854 | ||
855 | addi r8,r1,INT_FRAME_SIZE /* Get the kprobed function entry */ | |
856 | ||
857 | lwz r3,GPR1(r1) | |
858 | subi r3,r3,INT_FRAME_SIZE /* dst: Allocate a trampoline exception frame */ | |
859 | mr r4,r1 /* src: current exception frame */ | |
860 | mr r1,r3 /* Reroute the trampoline frame to r1 */ | |
861 | ||
862 | /* Copy from the original to the trampoline. */ | |
863 | li r5,INT_FRAME_SIZE/4 /* size: INT_FRAME_SIZE */ | |
864 | li r6,0 /* start offset: 0 */ | |
865 | mtctr r5 | |
866 | 2: lwzx r0,r6,r4 | |
867 | stwx r0,r6,r3 | |
868 | addi r6,r6,4 | |
869 | bdnz 2b | |
870 | ||
871 | /* Do real store operation to complete stwu */ | |
872 | lwz r5,GPR1(r1) | |
873 | stw r8,0(r5) | |
874 | ||
875 | /* Clear _TIF_EMULATE_STACK_STORE flag */ | |
876 | lis r11,_TIF_EMULATE_STACK_STORE@h | |
f7354cca | 877 | addi r5,r2,TI_FLAGS |
a9c4e541 TC |
878 | 0: lwarx r8,0,r5 |
879 | andc r8,r8,r11 | |
880 | #ifdef CONFIG_IBM405_ERR77 | |
881 | dcbt 0,r5 | |
882 | #endif | |
883 | stwcx. r8,0,r5 | |
884 | bne- 0b | |
885 | 1: | |
886 | ||
887 | #ifdef CONFIG_PREEMPT | |
888 | /* check current_thread_info->preempt_count */ | |
f7354cca | 889 | lwz r0,TI_PREEMPT(r2) |
9994a338 | 890 | cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ |
e2fb9f54 | 891 | bne restore_kuap |
a9c4e541 | 892 | andi. r8,r8,_TIF_NEED_RESCHED |
e2fb9f54 | 893 | beq+ restore_kuap |
a9c4e541 | 894 | lwz r3,_MSR(r1) |
9994a338 | 895 | andi. r0,r3,MSR_EE /* interrupts off? */ |
e2fb9f54 | 896 | beq restore_kuap /* don't schedule if so */ |
5d38902c BH |
897 | #ifdef CONFIG_TRACE_IRQFLAGS |
898 | /* Lockdep thinks irqs are enabled, we need to call | |
899 | * preempt_schedule_irq with IRQs off, so we inform lockdep | |
900 | * now that we -did- turn them off already | |
901 | */ | |
902 | bl trace_hardirqs_off | |
903 | #endif | |
90437bff | 904 | bl preempt_schedule_irq |
5d38902c BH |
905 | #ifdef CONFIG_TRACE_IRQFLAGS |
906 | /* And now, to properly rebalance the above, we tell lockdep they | |
907 | * are being turned back on, which will happen when we return | |
908 | */ | |
909 | bl trace_hardirqs_on | |
910 | #endif | |
9994a338 | 911 | #endif /* CONFIG_PREEMPT */ |
e2fb9f54 CL |
912 | restore_kuap: |
913 | kuap_restore r1, r2, r9, r10, r0 | |
9994a338 PM |
914 | |
915 | /* interrupts are hard-disabled at this point */ | |
916 | restore: | |
b98ac05d | 917 | #ifdef CONFIG_44x |
e7f75ad0 DK |
918 | BEGIN_MMU_FTR_SECTION |
919 | b 1f | |
920 | END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_47x) | |
b98ac05d BH |
921 | lis r4,icache_44x_need_flush@ha |
922 | lwz r5,icache_44x_need_flush@l(r4) | |
923 | cmplwi cr0,r5,0 | |
924 | beq+ 1f | |
925 | li r6,0 | |
926 | iccci r0,r0 | |
927 | stw r6,icache_44x_need_flush@l(r4) | |
928 | 1: | |
929 | #endif /* CONFIG_44x */ | |
5d38902c BH |
930 | |
931 | lwz r9,_MSR(r1) | |
932 | #ifdef CONFIG_TRACE_IRQFLAGS | |
933 | /* Lockdep doesn't know about the fact that IRQs are temporarily turned | |
934 | * off in this assembly code while peeking at TI_FLAGS() and such. However | |
935 | * we need to inform it if the exception turned interrupts off, and we | |
936 | * are about to trun them back on. | |
5d38902c BH |
937 | */ |
938 | andi. r10,r9,MSR_EE | |
939 | beq 1f | |
06ca2188 SR |
940 | stwu r1,-32(r1) |
941 | mflr r0 | |
942 | stw r0,4(r1) | |
5d38902c | 943 | bl trace_hardirqs_on |
d1865e71 | 944 | addi r1, r1, 32 |
5d38902c BH |
945 | lwz r9,_MSR(r1) |
946 | 1: | |
947 | #endif /* CONFIG_TRACE_IRQFLAGS */ | |
948 | ||
9994a338 PM |
949 | lwz r0,GPR0(r1) |
950 | lwz r2,GPR2(r1) | |
951 | REST_4GPRS(3, r1) | |
952 | REST_2GPRS(7, r1) | |
953 | ||
954 | lwz r10,_XER(r1) | |
955 | lwz r11,_CTR(r1) | |
956 | mtspr SPRN_XER,r10 | |
957 | mtctr r11 | |
958 | ||
959 | PPC405_ERR77(0,r1) | |
b64f87c1 BB |
960 | BEGIN_FTR_SECTION |
961 | lwarx r11,0,r1 | |
962 | END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX) | |
9994a338 PM |
963 | stwcx. r0,0,r1 /* to clear the reservation */ |
964 | ||
965 | #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) | |
9994a338 PM |
966 | andi. r10,r9,MSR_RI /* check if this exception occurred */ |
967 | beql nonrecoverable /* at a bad place (MSR:RI = 0) */ | |
968 | ||
969 | lwz r10,_CCR(r1) | |
970 | lwz r11,_LINK(r1) | |
971 | mtcrf 0xFF,r10 | |
972 | mtlr r11 | |
973 | ||
9580b71b CL |
974 | /* Clear the exception_marker on the stack to avoid confusing stacktrace */ |
975 | li r10, 0 | |
976 | stw r10, 8(r1) | |
9994a338 PM |
977 | /* |
978 | * Once we put values in SRR0 and SRR1, we are in a state | |
979 | * where exceptions are not recoverable, since taking an | |
980 | * exception will trash SRR0 and SRR1. Therefore we clear the | |
981 | * MSR:RI bit to indicate this. If we do take an exception, | |
982 | * we can't return to the point of the exception but we | |
983 | * can restart the exception exit path at the label | |
984 | * exc_exit_restart below. -- paulus | |
985 | */ | |
986 | LOAD_MSR_KERNEL(r10,MSR_KERNEL & ~MSR_RI) | |
987 | SYNC | |
988 | MTMSRD(r10) /* clear the RI bit */ | |
989 | .globl exc_exit_restart | |
990 | exc_exit_restart: | |
9994a338 | 991 | lwz r12,_NIP(r1) |
9994a338 PM |
992 | mtspr SPRN_SRR0,r12 |
993 | mtspr SPRN_SRR1,r9 | |
994 | REST_4GPRS(9, r1) | |
995 | lwz r1,GPR1(r1) | |
996 | .globl exc_exit_restart_end | |
997 | exc_exit_restart_end: | |
998 | SYNC | |
999 | RFI | |
1000 | ||
1001 | #else /* !(CONFIG_4xx || CONFIG_BOOKE) */ | |
1002 | /* | |
1003 | * This is a bit different on 4xx/Book-E because it doesn't have | |
1004 | * the RI bit in the MSR. | |
1005 | * The TLB miss handler checks if we have interrupted | |
1006 | * the exception exit path and restarts it if so | |
1007 | * (well maybe one day it will... :). | |
1008 | */ | |
1009 | lwz r11,_LINK(r1) | |
1010 | mtlr r11 | |
1011 | lwz r10,_CCR(r1) | |
1012 | mtcrf 0xff,r10 | |
9580b71b CL |
1013 | /* Clear the exception_marker on the stack to avoid confusing stacktrace */ |
1014 | li r10, 0 | |
1015 | stw r10, 8(r1) | |
9994a338 PM |
1016 | REST_2GPRS(9, r1) |
1017 | .globl exc_exit_restart | |
1018 | exc_exit_restart: | |
1019 | lwz r11,_NIP(r1) | |
1020 | lwz r12,_MSR(r1) | |
1021 | exc_exit_start: | |
1022 | mtspr SPRN_SRR0,r11 | |
1023 | mtspr SPRN_SRR1,r12 | |
1024 | REST_2GPRS(11, r1) | |
1025 | lwz r1,GPR1(r1) | |
1026 | .globl exc_exit_restart_end | |
1027 | exc_exit_restart_end: | |
1028 | PPC405_ERR77_SYNC | |
1029 | rfi | |
1030 | b . /* prevent prefetch past rfi */ | |
1031 | ||
1032 | /* | |
1033 | * Returning from a critical interrupt in user mode doesn't need | |
1034 | * to be any different from a normal exception. For a critical | |
1035 | * interrupt in the kernel, we just return (without checking for | |
1036 | * preemption) since the interrupt may have happened at some crucial | |
1037 | * place (e.g. inside the TLB miss handler), and because we will be | |
1038 | * running with r1 pointing into critical_stack, not the current | |
1039 | * process's kernel stack (and therefore current_thread_info() will | |
1040 | * give the wrong answer). | |
1041 | * We have to restore various SPRs that may have been in use at the | |
1042 | * time of the critical interrupt. | |
1043 | * | |
1044 | */ | |
1045 | #ifdef CONFIG_40x | |
1046 | #define PPC_40x_TURN_OFF_MSR_DR \ | |
1047 | /* avoid any possible TLB misses here by turning off MSR.DR, we \ | |
1048 | * assume the instructions here are mapped by a pinned TLB entry */ \ | |
1049 | li r10,MSR_IR; \ | |
1050 | mtmsr r10; \ | |
1051 | isync; \ | |
1052 | tophys(r1, r1); | |
1053 | #else | |
1054 | #define PPC_40x_TURN_OFF_MSR_DR | |
1055 | #endif | |
1056 | ||
1057 | #define RET_FROM_EXC_LEVEL(exc_lvl_srr0, exc_lvl_srr1, exc_lvl_rfi) \ | |
1058 | REST_NVGPRS(r1); \ | |
1059 | lwz r3,_MSR(r1); \ | |
1060 | andi. r3,r3,MSR_PR; \ | |
1061 | LOAD_MSR_KERNEL(r10,MSR_KERNEL); \ | |
1062 | bne user_exc_return; \ | |
1063 | lwz r0,GPR0(r1); \ | |
1064 | lwz r2,GPR2(r1); \ | |
1065 | REST_4GPRS(3, r1); \ | |
1066 | REST_2GPRS(7, r1); \ | |
1067 | lwz r10,_XER(r1); \ | |
1068 | lwz r11,_CTR(r1); \ | |
1069 | mtspr SPRN_XER,r10; \ | |
1070 | mtctr r11; \ | |
1071 | PPC405_ERR77(0,r1); \ | |
1072 | stwcx. r0,0,r1; /* to clear the reservation */ \ | |
1073 | lwz r11,_LINK(r1); \ | |
1074 | mtlr r11; \ | |
1075 | lwz r10,_CCR(r1); \ | |
1076 | mtcrf 0xff,r10; \ | |
1077 | PPC_40x_TURN_OFF_MSR_DR; \ | |
1078 | lwz r9,_DEAR(r1); \ | |
1079 | lwz r10,_ESR(r1); \ | |
1080 | mtspr SPRN_DEAR,r9; \ | |
1081 | mtspr SPRN_ESR,r10; \ | |
1082 | lwz r11,_NIP(r1); \ | |
1083 | lwz r12,_MSR(r1); \ | |
1084 | mtspr exc_lvl_srr0,r11; \ | |
1085 | mtspr exc_lvl_srr1,r12; \ | |
1086 | lwz r9,GPR9(r1); \ | |
1087 | lwz r12,GPR12(r1); \ | |
1088 | lwz r10,GPR10(r1); \ | |
1089 | lwz r11,GPR11(r1); \ | |
1090 | lwz r1,GPR1(r1); \ | |
1091 | PPC405_ERR77_SYNC; \ | |
1092 | exc_lvl_rfi; \ | |
1093 | b .; /* prevent prefetch past exc_lvl_rfi */ | |
1094 | ||
fca622c5 KG |
1095 | #define RESTORE_xSRR(exc_lvl_srr0, exc_lvl_srr1) \ |
1096 | lwz r9,_##exc_lvl_srr0(r1); \ | |
1097 | lwz r10,_##exc_lvl_srr1(r1); \ | |
1098 | mtspr SPRN_##exc_lvl_srr0,r9; \ | |
1099 | mtspr SPRN_##exc_lvl_srr1,r10; | |
1100 | ||
70fe3af8 | 1101 | #if defined(CONFIG_PPC_BOOK3E_MMU) |
fca622c5 KG |
1102 | #ifdef CONFIG_PHYS_64BIT |
1103 | #define RESTORE_MAS7 \ | |
1104 | lwz r11,MAS7(r1); \ | |
1105 | mtspr SPRN_MAS7,r11; | |
1106 | #else | |
1107 | #define RESTORE_MAS7 | |
1108 | #endif /* CONFIG_PHYS_64BIT */ | |
1109 | #define RESTORE_MMU_REGS \ | |
1110 | lwz r9,MAS0(r1); \ | |
1111 | lwz r10,MAS1(r1); \ | |
1112 | lwz r11,MAS2(r1); \ | |
1113 | mtspr SPRN_MAS0,r9; \ | |
1114 | lwz r9,MAS3(r1); \ | |
1115 | mtspr SPRN_MAS1,r10; \ | |
1116 | lwz r10,MAS6(r1); \ | |
1117 | mtspr SPRN_MAS2,r11; \ | |
1118 | mtspr SPRN_MAS3,r9; \ | |
1119 | mtspr SPRN_MAS6,r10; \ | |
1120 | RESTORE_MAS7; | |
1121 | #elif defined(CONFIG_44x) | |
1122 | #define RESTORE_MMU_REGS \ | |
1123 | lwz r9,MMUCR(r1); \ | |
1124 | mtspr SPRN_MMUCR,r9; | |
1125 | #else | |
1126 | #define RESTORE_MMU_REGS | |
1127 | #endif | |
1128 | ||
1129 | #ifdef CONFIG_40x | |
9994a338 PM |
1130 | .globl ret_from_crit_exc |
1131 | ret_from_crit_exc: | |
ee43eb78 | 1132 | mfspr r9,SPRN_SPRG_THREAD |
fca622c5 KG |
1133 | lis r10,saved_ksp_limit@ha; |
1134 | lwz r10,saved_ksp_limit@l(r10); | |
1135 | tovirt(r9,r9); | |
1136 | stw r10,KSP_LIMIT(r9) | |
1137 | lis r9,crit_srr0@ha; | |
1138 | lwz r9,crit_srr0@l(r9); | |
1139 | lis r10,crit_srr1@ha; | |
1140 | lwz r10,crit_srr1@l(r10); | |
1141 | mtspr SPRN_SRR0,r9; | |
1142 | mtspr SPRN_SRR1,r10; | |
16c57b36 | 1143 | RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI) |
fca622c5 | 1144 | #endif /* CONFIG_40x */ |
9994a338 PM |
1145 | |
1146 | #ifdef CONFIG_BOOKE | |
fca622c5 KG |
1147 | .globl ret_from_crit_exc |
1148 | ret_from_crit_exc: | |
ee43eb78 | 1149 | mfspr r9,SPRN_SPRG_THREAD |
fca622c5 KG |
1150 | lwz r10,SAVED_KSP_LIMIT(r1) |
1151 | stw r10,KSP_LIMIT(r9) | |
1152 | RESTORE_xSRR(SRR0,SRR1); | |
1153 | RESTORE_MMU_REGS; | |
16c57b36 | 1154 | RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI) |
fca622c5 | 1155 | |
9994a338 PM |
1156 | .globl ret_from_debug_exc |
1157 | ret_from_debug_exc: | |
ee43eb78 | 1158 | mfspr r9,SPRN_SPRG_THREAD |
fca622c5 KG |
1159 | lwz r10,SAVED_KSP_LIMIT(r1) |
1160 | stw r10,KSP_LIMIT(r9) | |
fca622c5 KG |
1161 | RESTORE_xSRR(SRR0,SRR1); |
1162 | RESTORE_xSRR(CSRR0,CSRR1); | |
1163 | RESTORE_MMU_REGS; | |
16c57b36 | 1164 | RET_FROM_EXC_LEVEL(SPRN_DSRR0, SPRN_DSRR1, PPC_RFDI) |
9994a338 PM |
1165 | |
1166 | .globl ret_from_mcheck_exc | |
1167 | ret_from_mcheck_exc: | |
ee43eb78 | 1168 | mfspr r9,SPRN_SPRG_THREAD |
fca622c5 KG |
1169 | lwz r10,SAVED_KSP_LIMIT(r1) |
1170 | stw r10,KSP_LIMIT(r9) | |
1171 | RESTORE_xSRR(SRR0,SRR1); | |
1172 | RESTORE_xSRR(CSRR0,CSRR1); | |
1173 | RESTORE_xSRR(DSRR0,DSRR1); | |
1174 | RESTORE_MMU_REGS; | |
16c57b36 | 1175 | RET_FROM_EXC_LEVEL(SPRN_MCSRR0, SPRN_MCSRR1, PPC_RFMCI) |
9994a338 PM |
1176 | #endif /* CONFIG_BOOKE */ |
1177 | ||
1178 | /* | |
1179 | * Load the DBCR0 value for a task that is being ptraced, | |
1180 | * having first saved away the global DBCR0. Note that r0 | |
1181 | * has the dbcr0 value to set upon entry to this. | |
1182 | */ | |
1183 | load_dbcr0: | |
1184 | mfmsr r10 /* first disable debug exceptions */ | |
1185 | rlwinm r10,r10,0,~MSR_DE | |
1186 | mtmsr r10 | |
1187 | isync | |
1188 | mfspr r10,SPRN_DBCR0 | |
1189 | lis r11,global_dbcr0@ha | |
1190 | addi r11,r11,global_dbcr0@l | |
4eaddb4d | 1191 | #ifdef CONFIG_SMP |
f7354cca | 1192 | lwz r9,TASK_CPU(r2) |
4eaddb4d KG |
1193 | slwi r9,r9,3 |
1194 | add r11,r11,r9 | |
1195 | #endif | |
9994a338 PM |
1196 | stw r10,0(r11) |
1197 | mtspr SPRN_DBCR0,r0 | |
1198 | lwz r10,4(r11) | |
1199 | addi r10,r10,1 | |
1200 | stw r10,4(r11) | |
1201 | li r11,-1 | |
1202 | mtspr SPRN_DBSR,r11 /* clear all pending debug events */ | |
1203 | blr | |
1204 | ||
991eb43a KG |
1205 | .section .bss |
1206 | .align 4 | |
b86fb888 | 1207 | .global global_dbcr0 |
991eb43a | 1208 | global_dbcr0: |
4eaddb4d | 1209 | .space 8*NR_CPUS |
991eb43a | 1210 | .previous |
9994a338 PM |
1211 | #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */ |
1212 | ||
1213 | do_work: /* r10 contains MSR_KERNEL here */ | |
1214 | andi. r0,r9,_TIF_NEED_RESCHED | |
1215 | beq do_user_signal | |
1216 | ||
1217 | do_resched: /* r10 contains MSR_KERNEL here */ | |
40530db7 CL |
1218 | #ifdef CONFIG_TRACE_IRQFLAGS |
1219 | bl trace_hardirqs_on | |
1220 | mfmsr r10 | |
1221 | #endif | |
9994a338 PM |
1222 | ori r10,r10,MSR_EE |
1223 | SYNC | |
1224 | MTMSRD(r10) /* hard-enable interrupts */ | |
1225 | bl schedule | |
1226 | recheck: | |
5d38902c BH |
1227 | /* Note: And we don't tell it we are disabling them again |
1228 | * neither. Those disable/enable cycles used to peek at | |
1229 | * TI_FLAGS aren't advertised. | |
1230 | */ | |
9994a338 PM |
1231 | LOAD_MSR_KERNEL(r10,MSR_KERNEL) |
1232 | SYNC | |
1233 | MTMSRD(r10) /* disable interrupts */ | |
f7354cca | 1234 | lwz r9,TI_FLAGS(r2) |
9994a338 PM |
1235 | andi. r0,r9,_TIF_NEED_RESCHED |
1236 | bne- do_resched | |
7a10174e | 1237 | andi. r0,r9,_TIF_USER_WORK_MASK |
9994a338 PM |
1238 | beq restore_user |
1239 | do_user_signal: /* r10 contains MSR_KERNEL here */ | |
1240 | ori r10,r10,MSR_EE | |
1241 | SYNC | |
1242 | MTMSRD(r10) /* hard-enable interrupts */ | |
1243 | /* save r13-r31 in the exception frame, if not already done */ | |
d73e0c99 | 1244 | lwz r3,_TRAP(r1) |
9994a338 PM |
1245 | andi. r0,r3,1 |
1246 | beq 2f | |
1247 | SAVE_NVGPRS(r1) | |
1248 | rlwinm r3,r3,0,0,30 | |
d73e0c99 | 1249 | stw r3,_TRAP(r1) |
7d6d637d RM |
1250 | 2: addi r3,r1,STACK_FRAME_OVERHEAD |
1251 | mr r4,r9 | |
18b246fa | 1252 | bl do_notify_resume |
9994a338 PM |
1253 | REST_NVGPRS(r1) |
1254 | b recheck | |
1255 | ||
1256 | /* | |
1257 | * We come here when we are at the end of handling an exception | |
1258 | * that occurred at a place where taking an exception will lose | |
1259 | * state information, such as the contents of SRR0 and SRR1. | |
1260 | */ | |
1261 | nonrecoverable: | |
1262 | lis r10,exc_exit_restart_end@ha | |
1263 | addi r10,r10,exc_exit_restart_end@l | |
1264 | cmplw r12,r10 | |
1265 | bge 3f | |
1266 | lis r11,exc_exit_restart@ha | |
1267 | addi r11,r11,exc_exit_restart@l | |
1268 | cmplw r12,r11 | |
1269 | blt 3f | |
1270 | lis r10,ee_restarts@ha | |
1271 | lwz r12,ee_restarts@l(r10) | |
1272 | addi r12,r12,1 | |
1273 | stw r12,ee_restarts@l(r10) | |
1274 | mr r12,r11 /* restart at exc_exit_restart */ | |
1275 | blr | |
1276 | 3: /* OK, we can't recover, kill this process */ | |
1277 | /* but the 601 doesn't implement the RI bit, so assume it's OK */ | |
1278 | BEGIN_FTR_SECTION | |
1279 | blr | |
1280 | END_FTR_SECTION_IFSET(CPU_FTR_601) | |
d73e0c99 | 1281 | lwz r3,_TRAP(r1) |
9994a338 | 1282 | andi. r0,r3,1 |
ed1cd6de | 1283 | beq 5f |
9994a338 PM |
1284 | SAVE_NVGPRS(r1) |
1285 | rlwinm r3,r3,0,0,30 | |
d73e0c99 | 1286 | stw r3,_TRAP(r1) |
ed1cd6de CL |
1287 | 5: mfspr r2,SPRN_SPRG_THREAD |
1288 | addi r2,r2,-THREAD | |
1289 | tovirt(r2,r2) /* set back r2 to current */ | |
9994a338 | 1290 | 4: addi r3,r1,STACK_FRAME_OVERHEAD |
51423a9c | 1291 | bl unrecoverable_exception |
9994a338 PM |
1292 | /* shouldn't return */ |
1293 | b 4b | |
1294 | ||
991eb43a KG |
1295 | .section .bss |
1296 | .align 2 | |
1297 | ee_restarts: | |
1298 | .space 4 | |
1299 | .previous | |
9994a338 PM |
1300 | |
1301 | /* | |
1302 | * PROM code for specific machines follows. Put it | |
1303 | * here so it's easy to add arch-specific sections later. | |
1304 | * -- Cort | |
1305 | */ | |
033ef338 | 1306 | #ifdef CONFIG_PPC_RTAS |
9994a338 PM |
1307 | /* |
1308 | * On CHRP, the Run-Time Abstraction Services (RTAS) have to be | |
1309 | * called with the MMU off. | |
1310 | */ | |
1311 | _GLOBAL(enter_rtas) | |
1312 | stwu r1,-INT_FRAME_SIZE(r1) | |
1313 | mflr r0 | |
1314 | stw r0,INT_FRAME_SIZE+4(r1) | |
e58c3495 | 1315 | LOAD_REG_ADDR(r4, rtas) |
9994a338 PM |
1316 | lis r6,1f@ha /* physical return address for rtas */ |
1317 | addi r6,r6,1f@l | |
1318 | tophys(r6,r6) | |
1319 | tophys(r7,r1) | |
033ef338 PM |
1320 | lwz r8,RTASENTRY(r4) |
1321 | lwz r4,RTASBASE(r4) | |
9994a338 PM |
1322 | mfmsr r9 |
1323 | stw r9,8(r1) | |
1324 | LOAD_MSR_KERNEL(r0,MSR_KERNEL) | |
1325 | SYNC /* disable interrupts so SRR0/1 */ | |
1326 | MTMSRD(r0) /* don't get trashed */ | |
1327 | li r9,MSR_KERNEL & ~(MSR_IR|MSR_DR) | |
1328 | mtlr r6 | |
0df977ea | 1329 | stw r7, THREAD + RTAS_SP(r2) |
9994a338 PM |
1330 | mtspr SPRN_SRR0,r8 |
1331 | mtspr SPRN_SRR1,r9 | |
1332 | RFI | |
1333 | 1: tophys(r9,r1) | |
1334 | lwz r8,INT_FRAME_SIZE+4(r9) /* get return address */ | |
1335 | lwz r9,8(r9) /* original msr value */ | |
9994a338 PM |
1336 | addi r1,r1,INT_FRAME_SIZE |
1337 | li r0,0 | |
0df977ea CL |
1338 | tophys(r7, r2) |
1339 | stw r0, THREAD + RTAS_SP(r7) | |
9994a338 PM |
1340 | mtspr SPRN_SRR0,r8 |
1341 | mtspr SPRN_SRR1,r9 | |
1342 | RFI /* return to caller */ | |
1343 | ||
1344 | .globl machine_check_in_rtas | |
1345 | machine_check_in_rtas: | |
1346 | twi 31,0,0 | |
1347 | /* XXX load up BATs and panic */ | |
1348 | ||
033ef338 | 1349 | #endif /* CONFIG_PPC_RTAS */ |