1 /* linux/arch/sparc/kernel/process.c
3 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
8 * This file handles the architecture-dependent parts of process handling..
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
18 #include <linux/stddef.h>
19 #include <linux/ptrace.h>
20 #include <linux/user.h>
21 #include <linux/smp.h>
22 #include <linux/reboot.h>
23 #include <linux/delay.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
28 #include <asm/auxio.h>
29 #include <asm/oplib.h>
30 #include <asm/uaccess.h>
31 #include <asm/system.h>
33 #include <asm/pgalloc.h>
34 #include <asm/pgtable.h>
35 #include <asm/delay.h>
36 #include <asm/processor.h>
40 #include <asm/unistd.h>
43 * Power management idle function
44 * Set in pm platform drivers (apc.c and pmc.c)
46 void (*pm_idle
)(void);
47 EXPORT_SYMBOL(pm_idle
);
50 * Power-off handler instantiation for pm.h compliance
51 * This is done via auxio, but could be used as a fallback
52 * handler when auxio is not present-- unused for now...
54 void (*pm_power_off
)(void) = machine_power_off
;
55 EXPORT_SYMBOL(pm_power_off
);
58 * sysctl - toggle power-off restriction for serial console
59 * systems in machine_power_off()
63 extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);
65 struct task_struct
*last_task_used_math
= NULL
;
66 struct thread_info
*current_set
[NR_CPUS
];
70 #define SUN4C_FAULT_HIGH 100
73 * the idle loop on a Sparc... ;)
77 /* endless idle loop with no priority at all */
80 static int count
= HZ
;
81 static unsigned long last_jiffies
;
82 static unsigned long last_faults
;
83 static unsigned long fps
;
87 extern unsigned long sun4c_kernel_faults
;
88 extern void sun4c_grow_kernel_ring(void);
92 count
-= (now
- last_jiffies
);
96 faults
= sun4c_kernel_faults
;
97 fps
= (fps
+ (faults
- last_faults
)) >> 1;
100 printk("kernel faults / second = %ld\n", fps
);
102 if (fps
>= SUN4C_FAULT_HIGH
) {
103 sun4c_grow_kernel_ring();
110 while (!need_resched())
113 while (!need_resched())
116 schedule_preempt_disabled();
123 /* This is being executed in task 0 'user space'. */
126 set_thread_flag(TIF_POLLING_NRFLAG
);
127 /* endless idle loop with no priority at all */
129 #ifdef CONFIG_SPARC_LEON
131 while (!need_resched())
136 while (!need_resched())
139 schedule_preempt_disabled();
146 /* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
147 void machine_halt(void)
153 panic("Halt failed!");
156 void machine_restart(char * cmd
)
164 p
= strchr (reboot_command
, '\n');
169 prom_reboot(reboot_command
);
170 prom_feval ("reset");
171 panic("Reboot failed!");
174 void machine_power_off(void)
176 if (auxio_power_register
&&
177 (strcmp(of_console_device
->type
, "serial") || scons_pwroff
))
178 *auxio_power_register
|= AUXIO_POWER_OFF
;
184 static DEFINE_SPINLOCK(sparc_backtrace_lock
);
186 void __show_backtrace(unsigned long fp
)
188 struct reg_window32
*rw
;
190 int cpu
= smp_processor_id();
192 spin_lock_irqsave(&sparc_backtrace_lock
, flags
);
194 rw
= (struct reg_window32
*)fp
;
195 while(rw
&& (((unsigned long) rw
) >= PAGE_OFFSET
) &&
196 !(((unsigned long) rw
) & 0x7)) {
197 printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] "
198 "FP[%08lx] CALLER[%08lx]: ", cpu
,
199 rw
->ins
[0], rw
->ins
[1], rw
->ins
[2], rw
->ins
[3],
200 rw
->ins
[4], rw
->ins
[5],
203 printk("%pS\n", (void *) rw
->ins
[7]);
204 rw
= (struct reg_window32
*) rw
->ins
[6];
206 spin_unlock_irqrestore(&sparc_backtrace_lock
, flags
);
209 #define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
210 #define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
211 #define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp))
213 void show_backtrace(void)
217 __SAVE
; __SAVE
; __SAVE
; __SAVE
;
218 __SAVE
; __SAVE
; __SAVE
; __SAVE
;
219 __RESTORE
; __RESTORE
; __RESTORE
; __RESTORE
;
220 __RESTORE
; __RESTORE
; __RESTORE
; __RESTORE
;
224 __show_backtrace(fp
);
228 void smp_show_backtrace_all_cpus(void)
230 xc0((smpfunc_t
) show_backtrace
);
235 void show_stackframe(struct sparc_stackf
*sf
)
241 printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx "
242 "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n",
243 sf
->locals
[0], sf
->locals
[1], sf
->locals
[2], sf
->locals
[3],
244 sf
->locals
[4], sf
->locals
[5], sf
->locals
[6], sf
->locals
[7]);
245 printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx "
246 "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n",
247 sf
->ins
[0], sf
->ins
[1], sf
->ins
[2], sf
->ins
[3],
248 sf
->ins
[4], sf
->ins
[5], (unsigned long)sf
->fp
, sf
->callers_pc
);
249 printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx "
250 "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n",
251 (unsigned long)sf
->structptr
, sf
->xargs
[0], sf
->xargs
[1],
252 sf
->xargs
[2], sf
->xargs
[3], sf
->xargs
[4], sf
->xargs
[5],
254 size
= ((unsigned long)sf
->fp
) - ((unsigned long)sf
);
255 size
-= STACKFRAME_SZ
;
256 stk
= (unsigned long *)((unsigned long)sf
+ STACKFRAME_SZ
);
259 printk("s%d: %08lx\n", i
++, *stk
++);
260 } while ((size
-= sizeof(unsigned long)));
264 void show_regs(struct pt_regs
*r
)
266 struct reg_window32
*rw
= (struct reg_window32
*) r
->u_regs
[14];
268 printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
269 r
->psr
, r
->pc
, r
->npc
, r
->y
, print_tainted());
270 printk("PC: <%pS>\n", (void *) r
->pc
);
271 printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
272 r
->u_regs
[0], r
->u_regs
[1], r
->u_regs
[2], r
->u_regs
[3],
273 r
->u_regs
[4], r
->u_regs
[5], r
->u_regs
[6], r
->u_regs
[7]);
274 printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
275 r
->u_regs
[8], r
->u_regs
[9], r
->u_regs
[10], r
->u_regs
[11],
276 r
->u_regs
[12], r
->u_regs
[13], r
->u_regs
[14], r
->u_regs
[15]);
277 printk("RPC: <%pS>\n", (void *) r
->u_regs
[15]);
279 printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
280 rw
->locals
[0], rw
->locals
[1], rw
->locals
[2], rw
->locals
[3],
281 rw
->locals
[4], rw
->locals
[5], rw
->locals
[6], rw
->locals
[7]);
282 printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
283 rw
->ins
[0], rw
->ins
[1], rw
->ins
[2], rw
->ins
[3],
284 rw
->ins
[4], rw
->ins
[5], rw
->ins
[6], rw
->ins
[7]);
288 * The show_stack is an external API which we do not use ourselves.
289 * The oops is printed in die_if_kernel.
291 void show_stack(struct task_struct
*tsk
, unsigned long *_ksp
)
293 unsigned long pc
, fp
;
294 unsigned long task_base
;
295 struct reg_window32
*rw
;
299 task_base
= (unsigned long) task_stack_page(tsk
);
301 task_base
= (unsigned long) current_thread_info();
303 fp
= (unsigned long) _ksp
;
305 /* Bogus frame pointer? */
306 if (fp
< (task_base
+ sizeof(struct thread_info
)) ||
307 fp
>= (task_base
+ (PAGE_SIZE
<< 1)))
309 rw
= (struct reg_window32
*) fp
;
311 printk("[%08lx : ", pc
);
312 printk("%pS ] ", (void *) pc
);
314 } while (++count
< 16);
318 void dump_stack(void)
322 __asm__
__volatile__("mov %%fp, %0"
324 show_stack(current
, ksp
);
327 EXPORT_SYMBOL(dump_stack
);
330 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
332 unsigned long thread_saved_pc(struct task_struct
*tsk
)
334 return task_thread_info(tsk
)->kpc
;
338 * Free current thread data structures etc..
340 void exit_thread(void)
343 if(last_task_used_math
== current
) {
345 if (test_thread_flag(TIF_USEDFPU
)) {
347 /* Keep process from leaving FPU in a bogon state. */
348 put_psr(get_psr() | PSR_EF
);
349 fpsave(¤t
->thread
.float_regs
[0], ¤t
->thread
.fsr
,
350 ¤t
->thread
.fpqueue
[0], ¤t
->thread
.fpqdepth
);
352 last_task_used_math
= NULL
;
354 clear_thread_flag(TIF_USEDFPU
);
359 void flush_thread(void)
361 current_thread_info()->w_saved
= 0;
364 if(last_task_used_math
== current
) {
366 if (test_thread_flag(TIF_USEDFPU
)) {
369 put_psr(get_psr() | PSR_EF
);
370 fpsave(¤t
->thread
.float_regs
[0], ¤t
->thread
.fsr
,
371 ¤t
->thread
.fpqueue
[0], ¤t
->thread
.fpqdepth
);
373 last_task_used_math
= NULL
;
375 clear_thread_flag(TIF_USEDFPU
);
379 /* This task is no longer a kernel thread. */
380 if (current
->thread
.flags
& SPARC_FLAG_KTHREAD
) {
381 current
->thread
.flags
&= ~SPARC_FLAG_KTHREAD
;
383 /* We must fixup kregs as well. */
384 /* XXX This was not fixed for ti for a while, worked. Unused? */
385 current
->thread
.kregs
= (struct pt_regs
*)
386 (task_stack_page(current
) + (THREAD_SIZE
- TRACEREG_SZ
));
390 static inline struct sparc_stackf __user
*
391 clone_stackframe(struct sparc_stackf __user
*dst
,
392 struct sparc_stackf __user
*src
)
394 unsigned long size
, fp
;
395 struct sparc_stackf
*tmp
;
396 struct sparc_stackf __user
*sp
;
398 if (get_user(tmp
, &src
->fp
))
401 fp
= (unsigned long) tmp
;
402 size
= (fp
- ((unsigned long) src
));
403 fp
= (unsigned long) dst
;
404 sp
= (struct sparc_stackf __user
*)(fp
- size
);
406 /* do_fork() grabs the parent semaphore, we must release it
407 * temporarily so we can build the child clone stack frame
408 * without deadlocking.
410 if (__copy_user(sp
, src
, size
))
412 else if (put_user(fp
, &sp
->fp
))
418 asmlinkage
int sparc_do_fork(unsigned long clone_flags
,
419 unsigned long stack_start
,
420 struct pt_regs
*regs
,
421 unsigned long stack_size
)
423 unsigned long parent_tid_ptr
, child_tid_ptr
;
424 unsigned long orig_i1
= regs
->u_regs
[UREG_I1
];
427 parent_tid_ptr
= regs
->u_regs
[UREG_I2
];
428 child_tid_ptr
= regs
->u_regs
[UREG_I4
];
430 ret
= do_fork(clone_flags
, stack_start
,
432 (int __user
*) parent_tid_ptr
,
433 (int __user
*) child_tid_ptr
);
435 /* If we get an error and potentially restart the system
436 * call, we're screwed because copy_thread() clobbered
437 * the parent's %o1. So detect that case and restore it
440 if ((unsigned long)ret
>= -ERESTART_RESTARTBLOCK
)
441 regs
->u_regs
[UREG_I1
] = orig_i1
;
446 /* Copy a Sparc thread. The fork() return value conventions
447 * under SunOS are nothing short of bletcherous:
448 * Parent --> %o0 == childs pid, %o1 == 0
449 * Child --> %o0 == parents pid, %o1 == 1
451 * NOTE: We have a separate fork kpsr/kwim because
452 * the parent could change these values between
453 * sys_fork invocation and when we reach here
454 * if the parent should sleep while trying to
455 * allocate the task_struct and kernel stack in
457 * XXX See comment above sys_vfork in sparc64. todo.
459 extern void ret_from_fork(void);
461 int copy_thread(unsigned long clone_flags
, unsigned long sp
,
462 unsigned long unused
,
463 struct task_struct
*p
, struct pt_regs
*regs
)
465 struct thread_info
*ti
= task_thread_info(p
);
466 struct pt_regs
*childregs
;
470 if(last_task_used_math
== current
) {
472 if (test_thread_flag(TIF_USEDFPU
)) {
474 put_psr(get_psr() | PSR_EF
);
475 fpsave(&p
->thread
.float_regs
[0], &p
->thread
.fsr
,
476 &p
->thread
.fpqueue
[0], &p
->thread
.fpqdepth
);
478 clear_thread_flag(TIF_USEDFPU
);
483 * p->thread_info new_stack childregs
484 * ! ! ! {if(PSR_PS) }
485 * V V (stk.fr.) V (pt_regs) { (stk.fr.) }
486 * +----- - - - - - ------+===========+============={+==========}+
488 new_stack
= task_stack_page(p
) + THREAD_SIZE
;
489 if (regs
->psr
& PSR_PS
)
490 new_stack
-= STACKFRAME_SZ
;
491 new_stack
-= STACKFRAME_SZ
+ TRACEREG_SZ
;
492 memcpy(new_stack
, (char *)regs
- STACKFRAME_SZ
, STACKFRAME_SZ
+ TRACEREG_SZ
);
493 childregs
= (struct pt_regs
*) (new_stack
+ STACKFRAME_SZ
);
496 * A new process must start with interrupts closed in 2.5,
497 * because this is how Mingo's scheduler works (see schedule_tail
498 * and finish_arch_switch). If we do not do it, a timer interrupt hits
499 * before we unlock, attempts to re-take the rq->lock, and then we die.
500 * Thus, kpsr|=PSR_PIL.
502 ti
->ksp
= (unsigned long) new_stack
;
503 ti
->kpc
= (((unsigned long) ret_from_fork
) - 0x8);
504 ti
->kpsr
= current
->thread
.fork_kpsr
| PSR_PIL
;
505 ti
->kwim
= current
->thread
.fork_kwim
;
507 if(regs
->psr
& PSR_PS
) {
508 extern struct pt_regs fake_swapper_regs
;
510 p
->thread
.kregs
= &fake_swapper_regs
;
511 new_stack
+= STACKFRAME_SZ
+ TRACEREG_SZ
;
512 childregs
->u_regs
[UREG_FP
] = (unsigned long) new_stack
;
513 p
->thread
.flags
|= SPARC_FLAG_KTHREAD
;
514 p
->thread
.current_ds
= KERNEL_DS
;
515 memcpy(new_stack
, (void *)regs
->u_regs
[UREG_FP
], STACKFRAME_SZ
);
516 childregs
->u_regs
[UREG_G6
] = (unsigned long) ti
;
518 p
->thread
.kregs
= childregs
;
519 childregs
->u_regs
[UREG_FP
] = sp
;
520 p
->thread
.flags
&= ~SPARC_FLAG_KTHREAD
;
521 p
->thread
.current_ds
= USER_DS
;
523 if (sp
!= regs
->u_regs
[UREG_FP
]) {
524 struct sparc_stackf __user
*childstack
;
525 struct sparc_stackf __user
*parentstack
;
528 * This is a clone() call with supplied user stack.
529 * Set some valid stack frames to give to the child.
531 childstack
= (struct sparc_stackf __user
*)
533 parentstack
= (struct sparc_stackf __user
*)
534 regs
->u_regs
[UREG_FP
];
537 printk("clone: parent stack:\n");
538 show_stackframe(parentstack
);
541 childstack
= clone_stackframe(childstack
, parentstack
);
546 printk("clone: child stack:\n");
547 show_stackframe(childstack
);
550 childregs
->u_regs
[UREG_FP
] = (unsigned long)childstack
;
555 /* FPU must be disabled on SMP. */
556 childregs
->psr
&= ~PSR_EF
;
559 /* Set the return value for the child. */
560 childregs
->u_regs
[UREG_I0
] = current
->pid
;
561 childregs
->u_regs
[UREG_I1
] = 1;
563 /* Set the return value for the parent. */
564 regs
->u_regs
[UREG_I1
] = 0;
566 if (clone_flags
& CLONE_SETTLS
)
567 childregs
->u_regs
[UREG_G7
] = regs
->u_regs
[UREG_I3
];
573 * fill in the fpu structure for a core dump.
575 int dump_fpu (struct pt_regs
* regs
, elf_fpregset_t
* fpregs
)
578 memset(fpregs
, 0, sizeof(*fpregs
));
579 fpregs
->pr_q_entrysize
= 8;
583 if (test_thread_flag(TIF_USEDFPU
)) {
584 put_psr(get_psr() | PSR_EF
);
585 fpsave(¤t
->thread
.float_regs
[0], ¤t
->thread
.fsr
,
586 ¤t
->thread
.fpqueue
[0], ¤t
->thread
.fpqdepth
);
588 regs
->psr
&= ~(PSR_EF
);
589 clear_thread_flag(TIF_USEDFPU
);
593 if (current
== last_task_used_math
) {
594 put_psr(get_psr() | PSR_EF
);
595 fpsave(¤t
->thread
.float_regs
[0], ¤t
->thread
.fsr
,
596 ¤t
->thread
.fpqueue
[0], ¤t
->thread
.fpqdepth
);
598 regs
->psr
&= ~(PSR_EF
);
599 last_task_used_math
= NULL
;
603 memcpy(&fpregs
->pr_fr
.pr_regs
[0],
604 ¤t
->thread
.float_regs
[0],
605 (sizeof(unsigned long) * 32));
606 fpregs
->pr_fsr
= current
->thread
.fsr
;
607 fpregs
->pr_qcnt
= current
->thread
.fpqdepth
;
608 fpregs
->pr_q_entrysize
= 8;
610 if(fpregs
->pr_qcnt
!= 0) {
611 memcpy(&fpregs
->pr_q
[0],
612 ¤t
->thread
.fpqueue
[0],
613 sizeof(struct fpq
) * fpregs
->pr_qcnt
);
615 /* Zero out the rest. */
616 memset(&fpregs
->pr_q
[fpregs
->pr_qcnt
], 0,
617 sizeof(struct fpq
) * (32 - fpregs
->pr_qcnt
));
622 * sparc_execve() executes a new program after the asm stub has set
623 * things up for us. This should basically do what I want it to.
625 asmlinkage
int sparc_execve(struct pt_regs
*regs
)
630 /* Check for indirect call. */
631 if(regs
->u_regs
[UREG_G1
] == 0)
634 filename
= getname((char __user
*)regs
->u_regs
[base
+ UREG_I0
]);
635 error
= PTR_ERR(filename
);
638 error
= do_execve(filename
,
639 (const char __user
*const __user
*)
640 regs
->u_regs
[base
+ UREG_I1
],
641 (const char __user
*const __user
*)
642 regs
->u_regs
[base
+ UREG_I2
],
650 * This is the mechanism for creating a new kernel thread.
652 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
653 * who haven't done an "execve()") should use this: it will work within
654 * a system call from a "real" process, but the process memory space will
655 * not be freed until both the parent and the child have exited.
657 pid_t
kernel_thread(int (*fn
)(void *), void * arg
, unsigned long flags
)
661 __asm__
__volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */
662 "mov %5, %%g3\n\t" /* and arg. */
664 "mov %2, %%o0\n\t" /* Clone flags. */
665 "mov 0, %%o1\n\t" /* usp arg == 0 */
666 "t 0x10\n\t" /* Linux/Sparc clone(). */
668 "be 1f\n\t" /* The parent, just return. */
669 " nop\n\t" /* Delay slot. */
670 "jmpl %%g2, %%o7\n\t" /* Call the function. */
671 " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
673 "t 0x10\n\t" /* Linux/Sparc exit(). */
674 /* Notreached by child. */
675 "1: mov %%o0, %0\n\t" :
677 "i" (__NR_clone
), "r" (flags
| CLONE_VM
| CLONE_UNTRACED
),
678 "i" (__NR_exit
), "r" (fn
), "r" (arg
) :
679 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
682 EXPORT_SYMBOL(kernel_thread
);
684 unsigned long get_wchan(struct task_struct
*task
)
686 unsigned long pc
, fp
, bias
= 0;
687 unsigned long task_base
= (unsigned long) task
;
688 unsigned long ret
= 0;
689 struct reg_window32
*rw
;
692 if (!task
|| task
== current
||
693 task
->state
== TASK_RUNNING
)
696 fp
= task_thread_info(task
)->ksp
+ bias
;
698 /* Bogus frame pointer? */
699 if (fp
< (task_base
+ sizeof(struct thread_info
)) ||
700 fp
>= (task_base
+ (2 * PAGE_SIZE
)))
702 rw
= (struct reg_window32
*) fp
;
704 if (!in_sched_functions(pc
)) {
708 fp
= rw
->ins
[6] + bias
;
709 } while (++count
< 16);