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[PATCH] powerpc: work around a cell interrupt HW bug
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / powerpc / kernel / process.c
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14cf11af 1/*
14cf11af
PM		 2 * Derived from "arch/i386/kernel/process.c"
3 * Copyright (C) 1995 Linus Torvalds
4 *
5 * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
6 * Paul Mackerras (paulus@cs.anu.edu.au)
7 *
8 * PowerPC version
9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16
17#include <linux/config.h>
18#include <linux/errno.h>
19#include <linux/sched.h>
20#include <linux/kernel.h>
21#include <linux/mm.h>
22#include <linux/smp.h>
23#include <linux/smp_lock.h>
24#include <linux/stddef.h>
25#include <linux/unistd.h>
26#include <linux/ptrace.h>
27#include <linux/slab.h>
28#include <linux/user.h>
29#include <linux/elf.h>
30#include <linux/init.h>
31#include <linux/prctl.h>
32#include <linux/init_task.h>
33#include <linux/module.h>
34#include <linux/kallsyms.h>
35#include <linux/mqueue.h>
36#include <linux/hardirq.h>
06d67d54 37#include <linux/utsname.h>
14cf11af
PM		 38
39#include <asm/pgtable.h>
40#include <asm/uaccess.h>
41#include <asm/system.h>
42#include <asm/io.h>
43#include <asm/processor.h>
44#include <asm/mmu.h>
45#include <asm/prom.h>
76032de8 46#include <asm/machdep.h>
c6622f63 47#include <asm/time.h>
06d67d54
PM		 48#ifdef CONFIG_PPC64
49#include <asm/firmware.h>
06d67d54 50#endif
14cf11af
PM		 51
52extern unsigned long _get_SP(void);
53
54#ifndef CONFIG_SMP
55struct task_struct *last_task_used_math = NULL;
56struct task_struct *last_task_used_altivec = NULL;
57struct task_struct *last_task_used_spe = NULL;
58#endif
59
14cf11af
PM		 60/*
61 * Make sure the floating-point register state in the
62 * the thread_struct is up to date for task tsk.
63 */
64void flush_fp_to_thread(struct task_struct *tsk)
65{
66 if (tsk->thread.regs) {
67 /*
68 * We need to disable preemption here because if we didn't,
69 * another process could get scheduled after the regs->msr
70 * test but before we have finished saving the FP registers
71 * to the thread_struct. That process could take over the
72 * FPU, and then when we get scheduled again we would store
73 * bogus values for the remaining FP registers.
74 */
75 preempt_disable();
76 if (tsk->thread.regs->msr & MSR_FP) {
77#ifdef CONFIG_SMP
78 /*
79 * This should only ever be called for current or
80 * for a stopped child process. Since we save away
81 * the FP register state on context switch on SMP,
82 * there is something wrong if a stopped child appears
83 * to still have its FP state in the CPU registers.
84 */
85 BUG_ON(tsk != current);
86#endif
87 giveup_fpu(current);
88 }
89 preempt_enable();
90 }
91}
92
93void enable_kernel_fp(void)
94{
95 WARN_ON(preemptible());
96
97#ifdef CONFIG_SMP
98 if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
99 giveup_fpu(current);
100 else
101 giveup_fpu(NULL); /* just enables FP for kernel */
102#else
103 giveup_fpu(last_task_used_math);
104#endif /* CONFIG_SMP */
105}
106EXPORT_SYMBOL(enable_kernel_fp);
107
108int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
109{
110 if (!tsk->thread.regs)
111 return 0;
112 flush_fp_to_thread(current);
113
114 memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs));
115
116 return 1;
117}
118
119#ifdef CONFIG_ALTIVEC
120void enable_kernel_altivec(void)
121{
122 WARN_ON(preemptible());
123
124#ifdef CONFIG_SMP
125 if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
126 giveup_altivec(current);
127 else
128 giveup_altivec(NULL); /* just enable AltiVec for kernel - force */
129#else
130 giveup_altivec(last_task_used_altivec);
131#endif /* CONFIG_SMP */
132}
133EXPORT_SYMBOL(enable_kernel_altivec);
134
135/*
136 * Make sure the VMX/Altivec register state in the
137 * the thread_struct is up to date for task tsk.
138 */
139void flush_altivec_to_thread(struct task_struct *tsk)
140{
141 if (tsk->thread.regs) {
142 preempt_disable();
143 if (tsk->thread.regs->msr & MSR_VEC) {
144#ifdef CONFIG_SMP
145 BUG_ON(tsk != current);
146#endif
147 giveup_altivec(current);
148 }
149 preempt_enable();
150 }
151}
152
153int dump_task_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs)
154{
155 flush_altivec_to_thread(current);
156 memcpy(vrregs, &current->thread.vr[0], sizeof(*vrregs));
157 return 1;
158}
159#endif /* CONFIG_ALTIVEC */
160
161#ifdef CONFIG_SPE
162
163void enable_kernel_spe(void)
164{
165 WARN_ON(preemptible());
166
167#ifdef CONFIG_SMP
168 if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
169 giveup_spe(current);
170 else
171 giveup_spe(NULL); /* just enable SPE for kernel - force */
172#else
173 giveup_spe(last_task_used_spe);
174#endif /* __SMP __ */
175}
176EXPORT_SYMBOL(enable_kernel_spe);
177
178void flush_spe_to_thread(struct task_struct *tsk)
179{
180 if (tsk->thread.regs) {
181 preempt_disable();
182 if (tsk->thread.regs->msr & MSR_SPE) {
183#ifdef CONFIG_SMP
184 BUG_ON(tsk != current);
185#endif
186 giveup_spe(current);
187 }
188 preempt_enable();
189 }
190}
191
192int dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs)
193{
194 flush_spe_to_thread(current);
195 /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */
196 memcpy(evrregs, &current->thread.evr[0], sizeof(u32) * 35);
197 return 1;
198}
199#endif /* CONFIG_SPE */
200
5388fb10 201#ifndef CONFIG_SMP
48abec07
PM		 202/*
203 * If we are doing lazy switching of CPU state (FP, altivec or SPE),
204 * and the current task has some state, discard it.
205 */
5388fb10 206void discard_lazy_cpu_state(void)
48abec07 207{
48abec07
PM		 208 preempt_disable();
209 if (last_task_used_math == current)
210 last_task_used_math = NULL;
211#ifdef CONFIG_ALTIVEC
212 if (last_task_used_altivec == current)
213 last_task_used_altivec = NULL;
214#endif /* CONFIG_ALTIVEC */
215#ifdef CONFIG_SPE
216 if (last_task_used_spe == current)
217 last_task_used_spe = NULL;
218#endif
219 preempt_enable();
48abec07 220}
5388fb10 221#endif /* CONFIG_SMP */
48abec07 222
624cee31 223#ifdef CONFIG_PPC_MERGE /* XXX for now */
14cf11af
PM		 224int set_dabr(unsigned long dabr)
225{
cab0af98
ME		 226 if (ppc_md.set_dabr)
227 return ppc_md.set_dabr(dabr);
14cf11af 228
cab0af98
ME		 229 mtspr(SPRN_DABR, dabr);
230 return 0;
14cf11af 231}
624cee31 232#endif
14cf11af 233
06d67d54
PM		 234#ifdef CONFIG_PPC64
235DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
14cf11af 236static DEFINE_PER_CPU(unsigned long, current_dabr);
06d67d54 237#endif
14cf11af
PM		 238
239struct task_struct *__switch_to(struct task_struct *prev,
240 struct task_struct *new)
241{
242 struct thread_struct *new_thread, *old_thread;
243 unsigned long flags;
244 struct task_struct *last;
245
246#ifdef CONFIG_SMP
247 /* avoid complexity of lazy save/restore of fpu
248 * by just saving it every time we switch out if
249 * this task used the fpu during the last quantum.
250 *
251 * If it tries to use the fpu again, it'll trap and
252 * reload its fp regs. So we don't have to do a restore
253 * every switch, just a save.
254 * -- Cort
255 */
256 if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
257 giveup_fpu(prev);
258#ifdef CONFIG_ALTIVEC
259 /*
260 * If the previous thread used altivec in the last quantum
261 * (thus changing altivec regs) then save them.
262 * We used to check the VRSAVE register but not all apps
263 * set it, so we don't rely on it now (and in fact we need
264 * to save & restore VSCR even if VRSAVE == 0). -- paulus
265 *
266 * On SMP we always save/restore altivec regs just to avoid the
267 * complexity of changing processors.
268 * -- Cort
269 */
270 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
271 giveup_altivec(prev);
14cf11af
PM		 272#endif /* CONFIG_ALTIVEC */
273#ifdef CONFIG_SPE
274 /*
275 * If the previous thread used spe in the last quantum
276 * (thus changing spe regs) then save them.
277 *
278 * On SMP we always save/restore spe regs just to avoid the
279 * complexity of changing processors.
280 */
281 if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
282 giveup_spe(prev);
c0c0d996
PM		 283#endif /* CONFIG_SPE */
284
285#else /* CONFIG_SMP */
286#ifdef CONFIG_ALTIVEC
287 /* Avoid the trap. On smp this this never happens since
288 * we don't set last_task_used_altivec -- Cort
289 */
290 if (new->thread.regs && last_task_used_altivec == new)
291 new->thread.regs->msr |= MSR_VEC;
292#endif /* CONFIG_ALTIVEC */
293#ifdef CONFIG_SPE
14cf11af
PM		 294 /* Avoid the trap. On smp this this never happens since
295 * we don't set last_task_used_spe
296 */
297 if (new->thread.regs && last_task_used_spe == new)
298 new->thread.regs->msr |= MSR_SPE;
299#endif /* CONFIG_SPE */
c0c0d996 300
14cf11af
PM		 301#endif /* CONFIG_SMP */
302
303#ifdef CONFIG_PPC64 /* for now */
304 if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) {
305 set_dabr(new->thread.dabr);
306 __get_cpu_var(current_dabr) = new->thread.dabr;
307 }
06d67d54
PM		 308
309 flush_tlb_pending();
14cf11af
PM		 310#endif
311
312 new_thread = &new->thread;
313 old_thread = &current->thread;
06d67d54
PM		 314
315#ifdef CONFIG_PPC64
316 /*
317 * Collect processor utilization data per process
318 */
319 if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
320 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
321 long unsigned start_tb, current_tb;
322 start_tb = old_thread->start_tb;
323 cu->current_tb = current_tb = mfspr(SPRN_PURR);
324 old_thread->accum_tb += (current_tb - start_tb);
325 new_thread->start_tb = current_tb;
326 }
327#endif
328
14cf11af 329 local_irq_save(flags);
c6622f63
PM		 330
331 account_system_vtime(current);
332 account_process_vtime(current);
333 calculate_steal_time();
334
14cf11af
PM		 335 last = _switch(old_thread, new_thread);
336
337 local_irq_restore(flags);
338
339 return last;
340}
341
06d67d54
PM		 342static int instructions_to_print = 16;
343
344#ifdef CONFIG_PPC64
345#define BAD_PC(pc) ((REGION_ID(pc) != KERNEL_REGION_ID) && \
346 (REGION_ID(pc) != VMALLOC_REGION_ID))
347#else
348#define BAD_PC(pc) ((pc) < KERNELBASE)
349#endif
350
351static void show_instructions(struct pt_regs *regs)
352{
353 int i;
354 unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
355 sizeof(int));
356
357 printk("Instruction dump:");
358
359 for (i = 0; i < instructions_to_print; i++) {
360 int instr;
361
362 if (!(i % 8))
363 printk("\n");
364
af308377
SR		 365 /* We use __get_user here *only* to avoid an OOPS on a
366 * bad address because the pc *should* only be a
367 * kernel address.
368 */
369 if (BAD_PC(pc) || __get_user(instr, (unsigned int __user *)pc)) {
06d67d54
PM		 370 printk("XXXXXXXX ");
371 } else {
372 if (regs->nip == pc)
373 printk("<%08x> ", instr);
374 else
375 printk("%08x ", instr);
376 }
377
378 pc += sizeof(int);
379 }
380
381 printk("\n");
382}
383
384static struct regbit {
385 unsigned long bit;
386 const char *name;
387} msr_bits[] = {
388 {MSR_EE, "EE"},
389 {MSR_PR, "PR"},
390 {MSR_FP, "FP"},
391 {MSR_ME, "ME"},
392 {MSR_IR, "IR"},
393 {MSR_DR, "DR"},
394 {0, NULL}
395};
396
397static void printbits(unsigned long val, struct regbit *bits)
398{
399 const char *sep = "";
400
401 printk("<");
402 for (; bits->bit; ++bits)
403 if (val & bits->bit) {
404 printk("%s%s", sep, bits->name);
405 sep = ",";
406 }
407 printk(">");
408}
409
410#ifdef CONFIG_PPC64
411#define REG "%016lX"
412#define REGS_PER_LINE 4
413#define LAST_VOLATILE 13
414#else
415#define REG "%08lX"
416#define REGS_PER_LINE 8
417#define LAST_VOLATILE 12
418#endif
419
14cf11af
PM		 420void show_regs(struct pt_regs * regs)
421{
422 int i, trap;
423
06d67d54
PM		 424 printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
425 regs->nip, regs->link, regs->ctr);
426 printk("REGS: %p TRAP: %04lx %s (%s)\n",
427 regs, regs->trap, print_tainted(), system_utsname.release);
428 printk("MSR: "REG" ", regs->msr);
429 printbits(regs->msr, msr_bits);
430 printk(" CR: %08lX XER: %08lX\n", regs->ccr, regs->xer);
14cf11af
PM		 431 trap = TRAP(regs);
432 if (trap == 0x300 || trap == 0x600)
06d67d54
PM		 433 printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
434 printk("TASK = %p[%d] '%s' THREAD: %p",
b5e2fc1c 435 current, current->pid, current->comm, task_thread_info(current));
14cf11af
PM		 436
437#ifdef CONFIG_SMP
438 printk(" CPU: %d", smp_processor_id());
439#endif /* CONFIG_SMP */
440
441 for (i = 0; i < 32; i++) {
06d67d54 442 if ((i % REGS_PER_LINE) == 0)
14cf11af 443 printk("\n" KERN_INFO "GPR%02d: ", i);
06d67d54
PM		 444 printk(REG " ", regs->gpr[i]);
445 if (i == LAST_VOLATILE && !FULL_REGS(regs))
14cf11af
PM		 446 break;
447 }
448 printk("\n");
449#ifdef CONFIG_KALLSYMS
450 /*
451 * Lookup NIP late so we have the best change of getting the
452 * above info out without failing
453 */
06d67d54 454 printk("NIP ["REG"] ", regs->nip);
14cf11af 455 print_symbol("%s\n", regs->nip);
06d67d54 456 printk("LR ["REG"] ", regs->link);
14cf11af
PM		 457 print_symbol("%s\n", regs->link);
458#endif
459 show_stack(current, (unsigned long *) regs->gpr[1]);
06d67d54
PM		 460 if (!user_mode(regs))
461 show_instructions(regs);
14cf11af
PM		 462}
463
464void exit_thread(void)
465{
48abec07 466 discard_lazy_cpu_state();
14cf11af
PM		 467}
468
469void flush_thread(void)
470{
06d67d54
PM		 471#ifdef CONFIG_PPC64
472 struct thread_info *t = current_thread_info();
473
474 if (t->flags & _TIF_ABI_PENDING)
475 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
476#endif
06d67d54 477
48abec07 478 discard_lazy_cpu_state();
14cf11af
PM		 479
480#ifdef CONFIG_PPC64 /* for now */
481 if (current->thread.dabr) {
482 current->thread.dabr = 0;
483 set_dabr(0);
484 }
485#endif
486}
487
488void
489release_thread(struct task_struct *t)
490{
491}
492
493/*
494 * This gets called before we allocate a new thread and copy
495 * the current task into it.
496 */
497void prepare_to_copy(struct task_struct *tsk)
498{
499 flush_fp_to_thread(current);
500 flush_altivec_to_thread(current);
501 flush_spe_to_thread(current);
502}
503
504/*
505 * Copy a thread..
506 */
06d67d54
PM		 507int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
508 unsigned long unused, struct task_struct *p,
509 struct pt_regs *regs)
14cf11af
PM		 510{
511 struct pt_regs *childregs, *kregs;
512 extern void ret_from_fork(void);
0cec6fd1 513 unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
14cf11af
PM		 514
515 CHECK_FULL_REGS(regs);
516 /* Copy registers */
517 sp -= sizeof(struct pt_regs);
518 childregs = (struct pt_regs *) sp;
519 *childregs = *regs;
520 if ((childregs->msr & MSR_PR) == 0) {
521 /* for kernel thread, set `current' and stackptr in new task */
522 childregs->gpr[1] = sp + sizeof(struct pt_regs);
06d67d54 523#ifdef CONFIG_PPC32
14cf11af 524 childregs->gpr[2] = (unsigned long) p;
06d67d54 525#else
b5e2fc1c 526 clear_tsk_thread_flag(p, TIF_32BIT);
06d67d54 527#endif
14cf11af
PM		 528 p->thread.regs = NULL; /* no user register state */
529 } else {
530 childregs->gpr[1] = usp;
531 p->thread.regs = childregs;
06d67d54
PM		 532 if (clone_flags & CLONE_SETTLS) {
533#ifdef CONFIG_PPC64
534 if (!test_thread_flag(TIF_32BIT))
535 childregs->gpr[13] = childregs->gpr[6];
536 else
537#endif
538 childregs->gpr[2] = childregs->gpr[6];
539 }
14cf11af
PM		 540 }
541 childregs->gpr[3] = 0; /* Result from fork() */
542 sp -= STACK_FRAME_OVERHEAD;
14cf11af
PM		 543
544 /*
545 * The way this works is that at some point in the future
546 * some task will call _switch to switch to the new task.
547 * That will pop off the stack frame created below and start
548 * the new task running at ret_from_fork. The new task will
549 * do some house keeping and then return from the fork or clone
550 * system call, using the stack frame created above.
551 */
552 sp -= sizeof(struct pt_regs);
553 kregs = (struct pt_regs *) sp;
554 sp -= STACK_FRAME_OVERHEAD;
555 p->thread.ksp = sp;
14cf11af 556
06d67d54
PM		 557#ifdef CONFIG_PPC64
558 if (cpu_has_feature(CPU_FTR_SLB)) {
559 unsigned long sp_vsid = get_kernel_vsid(sp);
3c726f8d 560 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
06d67d54
PM		 561
562 sp_vsid <<= SLB_VSID_SHIFT;
3c726f8d 563 sp_vsid |= SLB_VSID_KERNEL | llp;
06d67d54
PM		 564 p->thread.ksp_vsid = sp_vsid;
565 }
566
567 /*
568 * The PPC64 ABI makes use of a TOC to contain function
569 * pointers. The function (ret_from_except) is actually a pointer
570 * to the TOC entry. The first entry is a pointer to the actual
571 * function.
572 */
573 kregs->nip = *((unsigned long *)ret_from_fork);
574#else
575 kregs->nip = (unsigned long)ret_from_fork;
14cf11af 576 p->thread.last_syscall = -1;
06d67d54 577#endif
14cf11af
PM		 578
579 return 0;
580}
581
582/*
583 * Set up a thread for executing a new program
584 */
06d67d54 585void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
14cf11af 586{
90eac727
ME		 587#ifdef CONFIG_PPC64
588 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
589#endif
590
14cf11af 591 set_fs(USER_DS);
06d67d54
PM		 592
593 /*
594 * If we exec out of a kernel thread then thread.regs will not be
595 * set. Do it now.
596 */
597 if (!current->thread.regs) {
0cec6fd1
AV		 598 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
599 current->thread.regs = regs - 1;
06d67d54
PM		 600 }
601
14cf11af
PM		 602 memset(regs->gpr, 0, sizeof(regs->gpr));
603 regs->ctr = 0;
604 regs->link = 0;
605 regs->xer = 0;
606 regs->ccr = 0;
14cf11af 607 regs->gpr[1] = sp;
06d67d54
PM		 608
609#ifdef CONFIG_PPC32
610 regs->mq = 0;
611 regs->nip = start;
14cf11af 612 regs->msr = MSR_USER;
06d67d54 613#else
d4bf9a78 614 if (!test_thread_flag(TIF_32BIT)) {
90eac727 615 unsigned long entry, toc;
06d67d54
PM		 616
617 /* start is a relocated pointer to the function descriptor for
618 * the elf _start routine. The first entry in the function
619 * descriptor is the entry address of _start and the second
620 * entry is the TOC value we need to use.
621 */
622 __get_user(entry, (unsigned long __user *)start);
623 __get_user(toc, (unsigned long __user *)start+1);
624
625 /* Check whether the e_entry function descriptor entries
626 * need to be relocated before we can use them.
627 */
628 if (load_addr != 0) {
629 entry += load_addr;
630 toc += load_addr;
631 }
632 regs->nip = entry;
633 regs->gpr[2] = toc;
634 regs->msr = MSR_USER64;
d4bf9a78
SR		 635 } else {
636 regs->nip = start;
637 regs->gpr[2] = 0;
638 regs->msr = MSR_USER32;
06d67d54
PM		 639 }
640#endif
641
48abec07 642 discard_lazy_cpu_state();
14cf11af 643 memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
25c8a78b 644 current->thread.fpscr.val = 0;
14cf11af
PM		 645#ifdef CONFIG_ALTIVEC
646 memset(current->thread.vr, 0, sizeof(current->thread.vr));
647 memset(&current->thread.vscr, 0, sizeof(current->thread.vscr));
06d67d54 648 current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
14cf11af
PM		 649 current->thread.vrsave = 0;
650 current->thread.used_vr = 0;
651#endif /* CONFIG_ALTIVEC */
652#ifdef CONFIG_SPE
653 memset(current->thread.evr, 0, sizeof(current->thread.evr));
654 current->thread.acc = 0;
655 current->thread.spefscr = 0;
656 current->thread.used_spe = 0;
657#endif /* CONFIG_SPE */
658}
659
660#define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
661 | PR_FP_EXC_RES | PR_FP_EXC_INV)
662
663int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
664{
665 struct pt_regs *regs = tsk->thread.regs;
666
667 /* This is a bit hairy. If we are an SPE enabled processor
668 * (have embedded fp) we store the IEEE exception enable flags in
669 * fpexc_mode. fpexc_mode is also used for setting FP exception
670 * mode (asyn, precise, disabled) for 'Classic' FP. */
671 if (val & PR_FP_EXC_SW_ENABLE) {
672#ifdef CONFIG_SPE
673 tsk->thread.fpexc_mode = val &
674 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
06d67d54 675 return 0;
14cf11af
PM		 676#else
677 return -EINVAL;
678#endif
14cf11af 679 }
06d67d54
PM		 680
681 /* on a CONFIG_SPE this does not hurt us. The bits that
682 * __pack_fe01 use do not overlap with bits used for
683 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
684 * on CONFIG_SPE implementations are reserved so writing to
685 * them does not change anything */
686 if (val > PR_FP_EXC_PRECISE)
687 return -EINVAL;
688 tsk->thread.fpexc_mode = __pack_fe01(val);
689 if (regs != NULL && (regs->msr & MSR_FP) != 0)
690 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
691 | tsk->thread.fpexc_mode;
14cf11af
PM		 692 return 0;
693}
694
695int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
696{
697 unsigned int val;
698
699 if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
700#ifdef CONFIG_SPE
701 val = tsk->thread.fpexc_mode;
702#else
703 return -EINVAL;
704#endif
705 else
706 val = __unpack_fe01(tsk->thread.fpexc_mode);
707 return put_user(val, (unsigned int __user *) adr);
708}
709
06d67d54
PM		 710#define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
711
14cf11af
PM		 712int sys_clone(unsigned long clone_flags, unsigned long usp,
713 int __user *parent_tidp, void __user *child_threadptr,
714 int __user *child_tidp, int p6,
715 struct pt_regs *regs)
716{
717 CHECK_FULL_REGS(regs);
718 if (usp == 0)
719 usp = regs->gpr[1]; /* stack pointer for child */
06d67d54
PM		 720#ifdef CONFIG_PPC64
721 if (test_thread_flag(TIF_32BIT)) {
722 parent_tidp = TRUNC_PTR(parent_tidp);
723 child_tidp = TRUNC_PTR(child_tidp);
724 }
725#endif
14cf11af
PM		 726 return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
727}
728
729int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
730 unsigned long p4, unsigned long p5, unsigned long p6,
731 struct pt_regs *regs)
732{
733 CHECK_FULL_REGS(regs);
734 return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
735}
736
737int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
738 unsigned long p4, unsigned long p5, unsigned long p6,
739 struct pt_regs *regs)
740{
741 CHECK_FULL_REGS(regs);
742 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
743 regs, 0, NULL, NULL);
744}
745
746int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
747 unsigned long a3, unsigned long a4, unsigned long a5,
748 struct pt_regs *regs)
749{
750 int error;
06d67d54 751 char *filename;
14cf11af
PM		 752
753 filename = getname((char __user *) a0);
754 error = PTR_ERR(filename);
755 if (IS_ERR(filename))
756 goto out;
757 flush_fp_to_thread(current);
758 flush_altivec_to_thread(current);
759 flush_spe_to_thread(current);
20c8c210
PM		 760 error = do_execve(filename, (char __user * __user *) a1,
761 (char __user * __user *) a2, regs);
14cf11af
PM		 762 if (error == 0) {
763 task_lock(current);
764 current->ptrace &= ~PT_DTRACE;
765 task_unlock(current);
766 }
767 putname(filename);
768out:
769 return error;
770}
771
772static int validate_sp(unsigned long sp, struct task_struct *p,
773 unsigned long nbytes)
774{
0cec6fd1 775 unsigned long stack_page = (unsigned long)task_stack_page(p);
14cf11af
PM		 776
777 if (sp >= stack_page + sizeof(struct thread_struct)
778 && sp <= stack_page + THREAD_SIZE - nbytes)
779 return 1;
780
781#ifdef CONFIG_IRQSTACKS
782 stack_page = (unsigned long) hardirq_ctx[task_cpu(p)];
783 if (sp >= stack_page + sizeof(struct thread_struct)
784 && sp <= stack_page + THREAD_SIZE - nbytes)
785 return 1;
786
787 stack_page = (unsigned long) softirq_ctx[task_cpu(p)];
788 if (sp >= stack_page + sizeof(struct thread_struct)
789 && sp <= stack_page + THREAD_SIZE - nbytes)
790 return 1;
791#endif
792
793 return 0;
794}
795
06d67d54
PM		 796#ifdef CONFIG_PPC64
797#define MIN_STACK_FRAME 112 /* same as STACK_FRAME_OVERHEAD, in fact */
798#define FRAME_LR_SAVE 2
799#define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD + 288)
800#define REGS_MARKER 0x7265677368657265ul
801#define FRAME_MARKER 12
802#else
803#define MIN_STACK_FRAME 16
804#define FRAME_LR_SAVE 1
805#define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
806#define REGS_MARKER 0x72656773ul
807#define FRAME_MARKER 2
14cf11af 808#endif
14cf11af
PM		 809
810unsigned long get_wchan(struct task_struct *p)
811{
812 unsigned long ip, sp;
813 int count = 0;
814
815 if (!p || p == current || p->state == TASK_RUNNING)
816 return 0;
817
818 sp = p->thread.ksp;
06d67d54 819 if (!validate_sp(sp, p, MIN_STACK_FRAME))
14cf11af
PM		 820 return 0;
821
822 do {
823 sp = *(unsigned long *)sp;
06d67d54 824 if (!validate_sp(sp, p, MIN_STACK_FRAME))
14cf11af
PM		 825 return 0;
826 if (count > 0) {
06d67d54 827 ip = ((unsigned long *)sp)[FRAME_LR_SAVE];
14cf11af
PM		 828 if (!in_sched_functions(ip))
829 return ip;
830 }
831 } while (count++ < 16);
832 return 0;
833}
834EXPORT_SYMBOL(get_wchan);
06d67d54
PM		 835
836static int kstack_depth_to_print = 64;
837
838void show_stack(struct task_struct *tsk, unsigned long *stack)
839{
840 unsigned long sp, ip, lr, newsp;
841 int count = 0;
842 int firstframe = 1;
843
844 sp = (unsigned long) stack;
845 if (tsk == NULL)
846 tsk = current;
847 if (sp == 0) {
848 if (tsk == current)
849 asm("mr %0,1" : "=r" (sp));
850 else
851 sp = tsk->thread.ksp;
852 }
853
854 lr = 0;
855 printk("Call Trace:\n");
856 do {
857 if (!validate_sp(sp, tsk, MIN_STACK_FRAME))
858 return;
859
860 stack = (unsigned long *) sp;
861 newsp = stack[0];
862 ip = stack[FRAME_LR_SAVE];
863 if (!firstframe || ip != lr) {
864 printk("["REG"] ["REG"] ", sp, ip);
865 print_symbol("%s", ip);
866 if (firstframe)
867 printk(" (unreliable)");
868 printk("\n");
869 }
870 firstframe = 0;
871
872 /*
873 * See if this is an exception frame.
874 * We look for the "regshere" marker in the current frame.
875 */
876 if (validate_sp(sp, tsk, INT_FRAME_SIZE)
877 && stack[FRAME_MARKER] == REGS_MARKER) {
878 struct pt_regs *regs = (struct pt_regs *)
879 (sp + STACK_FRAME_OVERHEAD);
880 printk("--- Exception: %lx", regs->trap);
881 print_symbol(" at %s\n", regs->nip);
882 lr = regs->link;
883 print_symbol(" LR = %s\n", lr);
884 firstframe = 1;
885 }
886
887 sp = newsp;
888 } while (count++ < kstack_depth_to_print);
889}
890
891void dump_stack(void)
892{
893 show_stack(current, NULL);
894}
895EXPORT_SYMBOL(dump_stack);
cb2c9b27
AB		 896
897#ifdef CONFIG_PPC64
898void ppc64_runlatch_on(void)
899{
900 unsigned long ctrl;
901
902 if (cpu_has_feature(CPU_FTR_CTRL) && !test_thread_flag(TIF_RUNLATCH)) {
903 HMT_medium();
904
905 ctrl = mfspr(SPRN_CTRLF);
906 ctrl |= CTRL_RUNLATCH;
907 mtspr(SPRN_CTRLT, ctrl);
908
909 set_thread_flag(TIF_RUNLATCH);
910 }
911}
912
913void ppc64_runlatch_off(void)
914{
915 unsigned long ctrl;
916
917 if (cpu_has_feature(CPU_FTR_CTRL) && test_thread_flag(TIF_RUNLATCH)) {
918 HMT_medium();
919
920 clear_thread_flag(TIF_RUNLATCH);
921
922 ctrl = mfspr(SPRN_CTRLF);
923 ctrl &= ~CTRL_RUNLATCH;
924 mtspr(SPRN_CTRLT, ctrl);
925 }
926}
927#endif
kernel source for telekom puls (alcatel/mediatek)