2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * arch/sh64/kernel/process.c
8 * Copyright (C) 2000, 2001 Paolo Alberelli
9 * Copyright (C) 2003 Paul Mundt
10 * Copyright (C) 2003, 2004 Richard Curnow
12 * Started from SH3/4 version:
13 * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
15 * In turn started from i386 version:
16 * Copyright (C) 1995 Linus Torvalds
21 * This file handles the architecture-dependent parts of process handling..
24 #include <linux/ptrace.h>
25 #include <linux/reboot.h>
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <asm/uaccess.h>
29 #include <asm/pgtable.h>
31 struct task_struct *last_task_used_math = NULL;
33 static int hlt_counter = 1;
35 #define HARD_IDLE_TIMEOUT (HZ / 3)
37 void disable_hlt(void)
47 static int __init nohlt_setup(char *__unused)
53 static int __init hlt_setup(char *__unused)
59 __setup("nohlt", nohlt_setup);
60 __setup("hlt", hlt_setup);
62 static inline void hlt(void)
64 __asm__ __volatile__ ("sleep" : : : "memory");
68 * The idle loop on a uniprocessor SH..
72 /* endless idle loop with no priority at all */
75 while (!need_resched())
79 while (!need_resched()) {
86 preempt_enable_no_resched();
93 void machine_restart(char * __unused)
95 extern void phys_stext(void);
100 void machine_halt(void)
105 void machine_power_off(void)
107 extern void enter_deep_standby(void);
109 enter_deep_standby();
112 void (*pm_power_off)(void) = machine_power_off;
113 EXPORT_SYMBOL(pm_power_off);
115 void show_regs(struct pt_regs * regs)
117 unsigned long long ah, al, bh, bl, ch, cl;
121 ah = (regs->pc) >> 32;
122 al = (regs->pc) & 0xffffffff;
123 bh = (regs->regs[18]) >> 32;
124 bl = (regs->regs[18]) & 0xffffffff;
125 ch = (regs->regs[15]) >> 32;
126 cl = (regs->regs[15]) & 0xffffffff;
127 printk("PC : %08Lx%08Lx LINK: %08Lx%08Lx SP : %08Lx%08Lx\n",
128 ah, al, bh, bl, ch, cl);
130 ah = (regs->sr) >> 32;
131 al = (regs->sr) & 0xffffffff;
132 asm volatile ("getcon " __TEA ", %0" : "=r" (bh));
133 asm volatile ("getcon " __TEA ", %0" : "=r" (bl));
135 bl = (bl) & 0xffffffff;
136 asm volatile ("getcon " __KCR0 ", %0" : "=r" (ch));
137 asm volatile ("getcon " __KCR0 ", %0" : "=r" (cl));
139 cl = (cl) & 0xffffffff;
140 printk("SR : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
141 ah, al, bh, bl, ch, cl);
143 ah = (regs->regs[0]) >> 32;
144 al = (regs->regs[0]) & 0xffffffff;
145 bh = (regs->regs[1]) >> 32;
146 bl = (regs->regs[1]) & 0xffffffff;
147 ch = (regs->regs[2]) >> 32;
148 cl = (regs->regs[2]) & 0xffffffff;
149 printk("R0 : %08Lx%08Lx R1 : %08Lx%08Lx R2 : %08Lx%08Lx\n",
150 ah, al, bh, bl, ch, cl);
152 ah = (regs->regs[3]) >> 32;
153 al = (regs->regs[3]) & 0xffffffff;
154 bh = (regs->regs[4]) >> 32;
155 bl = (regs->regs[4]) & 0xffffffff;
156 ch = (regs->regs[5]) >> 32;
157 cl = (regs->regs[5]) & 0xffffffff;
158 printk("R3 : %08Lx%08Lx R4 : %08Lx%08Lx R5 : %08Lx%08Lx\n",
159 ah, al, bh, bl, ch, cl);
161 ah = (regs->regs[6]) >> 32;
162 al = (regs->regs[6]) & 0xffffffff;
163 bh = (regs->regs[7]) >> 32;
164 bl = (regs->regs[7]) & 0xffffffff;
165 ch = (regs->regs[8]) >> 32;
166 cl = (regs->regs[8]) & 0xffffffff;
167 printk("R6 : %08Lx%08Lx R7 : %08Lx%08Lx R8 : %08Lx%08Lx\n",
168 ah, al, bh, bl, ch, cl);
170 ah = (regs->regs[9]) >> 32;
171 al = (regs->regs[9]) & 0xffffffff;
172 bh = (regs->regs[10]) >> 32;
173 bl = (regs->regs[10]) & 0xffffffff;
174 ch = (regs->regs[11]) >> 32;
175 cl = (regs->regs[11]) & 0xffffffff;
176 printk("R9 : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
177 ah, al, bh, bl, ch, cl);
179 ah = (regs->regs[12]) >> 32;
180 al = (regs->regs[12]) & 0xffffffff;
181 bh = (regs->regs[13]) >> 32;
182 bl = (regs->regs[13]) & 0xffffffff;
183 ch = (regs->regs[14]) >> 32;
184 cl = (regs->regs[14]) & 0xffffffff;
185 printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
186 ah, al, bh, bl, ch, cl);
188 ah = (regs->regs[16]) >> 32;
189 al = (regs->regs[16]) & 0xffffffff;
190 bh = (regs->regs[17]) >> 32;
191 bl = (regs->regs[17]) & 0xffffffff;
192 ch = (regs->regs[19]) >> 32;
193 cl = (regs->regs[19]) & 0xffffffff;
194 printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
195 ah, al, bh, bl, ch, cl);
197 ah = (regs->regs[20]) >> 32;
198 al = (regs->regs[20]) & 0xffffffff;
199 bh = (regs->regs[21]) >> 32;
200 bl = (regs->regs[21]) & 0xffffffff;
201 ch = (regs->regs[22]) >> 32;
202 cl = (regs->regs[22]) & 0xffffffff;
203 printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
204 ah, al, bh, bl, ch, cl);
206 ah = (regs->regs[23]) >> 32;
207 al = (regs->regs[23]) & 0xffffffff;
208 bh = (regs->regs[24]) >> 32;
209 bl = (regs->regs[24]) & 0xffffffff;
210 ch = (regs->regs[25]) >> 32;
211 cl = (regs->regs[25]) & 0xffffffff;
212 printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
213 ah, al, bh, bl, ch, cl);
215 ah = (regs->regs[26]) >> 32;
216 al = (regs->regs[26]) & 0xffffffff;
217 bh = (regs->regs[27]) >> 32;
218 bl = (regs->regs[27]) & 0xffffffff;
219 ch = (regs->regs[28]) >> 32;
220 cl = (regs->regs[28]) & 0xffffffff;
221 printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
222 ah, al, bh, bl, ch, cl);
224 ah = (regs->regs[29]) >> 32;
225 al = (regs->regs[29]) & 0xffffffff;
226 bh = (regs->regs[30]) >> 32;
227 bl = (regs->regs[30]) & 0xffffffff;
228 ch = (regs->regs[31]) >> 32;
229 cl = (regs->regs[31]) & 0xffffffff;
230 printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
231 ah, al, bh, bl, ch, cl);
233 ah = (regs->regs[32]) >> 32;
234 al = (regs->regs[32]) & 0xffffffff;
235 bh = (regs->regs[33]) >> 32;
236 bl = (regs->regs[33]) & 0xffffffff;
237 ch = (regs->regs[34]) >> 32;
238 cl = (regs->regs[34]) & 0xffffffff;
239 printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
240 ah, al, bh, bl, ch, cl);
242 ah = (regs->regs[35]) >> 32;
243 al = (regs->regs[35]) & 0xffffffff;
244 bh = (regs->regs[36]) >> 32;
245 bl = (regs->regs[36]) & 0xffffffff;
246 ch = (regs->regs[37]) >> 32;
247 cl = (regs->regs[37]) & 0xffffffff;
248 printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
249 ah, al, bh, bl, ch, cl);
251 ah = (regs->regs[38]) >> 32;
252 al = (regs->regs[38]) & 0xffffffff;
253 bh = (regs->regs[39]) >> 32;
254 bl = (regs->regs[39]) & 0xffffffff;
255 ch = (regs->regs[40]) >> 32;
256 cl = (regs->regs[40]) & 0xffffffff;
257 printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
258 ah, al, bh, bl, ch, cl);
260 ah = (regs->regs[41]) >> 32;
261 al = (regs->regs[41]) & 0xffffffff;
262 bh = (regs->regs[42]) >> 32;
263 bl = (regs->regs[42]) & 0xffffffff;
264 ch = (regs->regs[43]) >> 32;
265 cl = (regs->regs[43]) & 0xffffffff;
266 printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
267 ah, al, bh, bl, ch, cl);
269 ah = (regs->regs[44]) >> 32;
270 al = (regs->regs[44]) & 0xffffffff;
271 bh = (regs->regs[45]) >> 32;
272 bl = (regs->regs[45]) & 0xffffffff;
273 ch = (regs->regs[46]) >> 32;
274 cl = (regs->regs[46]) & 0xffffffff;
275 printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
276 ah, al, bh, bl, ch, cl);
278 ah = (regs->regs[47]) >> 32;
279 al = (regs->regs[47]) & 0xffffffff;
280 bh = (regs->regs[48]) >> 32;
281 bl = (regs->regs[48]) & 0xffffffff;
282 ch = (regs->regs[49]) >> 32;
283 cl = (regs->regs[49]) & 0xffffffff;
284 printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
285 ah, al, bh, bl, ch, cl);
287 ah = (regs->regs[50]) >> 32;
288 al = (regs->regs[50]) & 0xffffffff;
289 bh = (regs->regs[51]) >> 32;
290 bl = (regs->regs[51]) & 0xffffffff;
291 ch = (regs->regs[52]) >> 32;
292 cl = (regs->regs[52]) & 0xffffffff;
293 printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
294 ah, al, bh, bl, ch, cl);
296 ah = (regs->regs[53]) >> 32;
297 al = (regs->regs[53]) & 0xffffffff;
298 bh = (regs->regs[54]) >> 32;
299 bl = (regs->regs[54]) & 0xffffffff;
300 ch = (regs->regs[55]) >> 32;
301 cl = (regs->regs[55]) & 0xffffffff;
302 printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
303 ah, al, bh, bl, ch, cl);
305 ah = (regs->regs[56]) >> 32;
306 al = (regs->regs[56]) & 0xffffffff;
307 bh = (regs->regs[57]) >> 32;
308 bl = (regs->regs[57]) & 0xffffffff;
309 ch = (regs->regs[58]) >> 32;
310 cl = (regs->regs[58]) & 0xffffffff;
311 printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
312 ah, al, bh, bl, ch, cl);
314 ah = (regs->regs[59]) >> 32;
315 al = (regs->regs[59]) & 0xffffffff;
316 bh = (regs->regs[60]) >> 32;
317 bl = (regs->regs[60]) & 0xffffffff;
318 ch = (regs->regs[61]) >> 32;
319 cl = (regs->regs[61]) & 0xffffffff;
320 printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
321 ah, al, bh, bl, ch, cl);
323 ah = (regs->regs[62]) >> 32;
324 al = (regs->regs[62]) & 0xffffffff;
325 bh = (regs->tregs[0]) >> 32;
326 bl = (regs->tregs[0]) & 0xffffffff;
327 ch = (regs->tregs[1]) >> 32;
328 cl = (regs->tregs[1]) & 0xffffffff;
329 printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n",
330 ah, al, bh, bl, ch, cl);
332 ah = (regs->tregs[2]) >> 32;
333 al = (regs->tregs[2]) & 0xffffffff;
334 bh = (regs->tregs[3]) >> 32;
335 bl = (regs->tregs[3]) & 0xffffffff;
336 ch = (regs->tregs[4]) >> 32;
337 cl = (regs->tregs[4]) & 0xffffffff;
338 printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n",
339 ah, al, bh, bl, ch, cl);
341 ah = (regs->tregs[5]) >> 32;
342 al = (regs->tregs[5]) & 0xffffffff;
343 bh = (regs->tregs[6]) >> 32;
344 bl = (regs->tregs[6]) & 0xffffffff;
345 ch = (regs->tregs[7]) >> 32;
346 cl = (regs->tregs[7]) & 0xffffffff;
347 printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n",
348 ah, al, bh, bl, ch, cl);
351 * If we're in kernel mode, dump the stack too..
353 if (!user_mode(regs)) {
354 void show_stack(struct task_struct *tsk, unsigned long *sp);
355 unsigned long sp = regs->regs[15] & 0xffffffff;
356 struct task_struct *tsk = get_current();
358 tsk->thread.kregs = regs;
360 show_stack(tsk, (unsigned long *)sp);
364 struct task_struct * alloc_task_struct(void)
366 /* Get task descriptor pages */
367 return (struct task_struct *)
368 __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE));
371 void free_task_struct(struct task_struct *p)
373 free_pages((unsigned long) p, get_order(THREAD_SIZE));
377 * Create a kernel thread
379 ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
385 * This is the mechanism for creating a new kernel thread.
387 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
388 * who haven't done an "execve()") should use this: it will work within
389 * a system call from a "real" process, but the process memory space will
390 * not be freed until both the parent and the child have exited.
392 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
396 memset(®s, 0, sizeof(regs));
397 regs.regs[2] = (unsigned long)arg;
398 regs.regs[3] = (unsigned long)fn;
400 regs.pc = (unsigned long)kernel_thread_helper;
403 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
404 ®s, 0, NULL, NULL);
408 * Free current thread data structures etc..
410 void exit_thread(void)
412 /* See arch/sparc/kernel/process.c for the precedent for doing this -- RPC.
414 The SH-5 FPU save/restore approach relies on last_task_used_math
415 pointing to a live task_struct. When another task tries to use the
416 FPU for the 1st time, the FPUDIS trap handling (see
417 arch/sh64/kernel/fpu.c) will save the existing FPU state to the
418 FP regs field within last_task_used_math before re-loading the new
419 task's FPU state (or initialising it if the FPU has been used
420 before). So if last_task_used_math is stale, and its page has already been
421 re-allocated for another use, the consequences are rather grim. Unless we
422 null it here, there is no other path through which it would get safely
426 if (last_task_used_math == current) {
427 last_task_used_math = NULL;
432 void flush_thread(void)
435 /* Called by fs/exec.c (flush_old_exec) to remove traces of a
436 * previously running executable. */
438 if (last_task_used_math == current) {
439 last_task_used_math = NULL;
441 /* Force FPU state to be reinitialised after exec */
445 /* if we are a kernel thread, about to change to user thread,
448 if(current->thread.kregs==&fake_swapper_regs) {
449 current->thread.kregs =
450 ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
451 current->thread.uregs = current->thread.kregs;
455 void release_thread(struct task_struct *dead_task)
460 /* Fill in the fpu structure for a core dump.. */
461 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
465 struct task_struct *tsk = current;
467 fpvalid = !!tsk_used_math(tsk);
469 if (current == last_task_used_math) {
471 fpsave(&tsk->thread.fpu.hard);
473 last_task_used_math = 0;
477 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
482 return 0; /* Task didn't use the fpu at all. */
486 asmlinkage void ret_from_fork(void);
488 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
489 unsigned long unused,
490 struct task_struct *p, struct pt_regs *regs)
492 struct pt_regs *childregs;
493 unsigned long long se; /* Sign extension */
496 if(last_task_used_math == current) {
498 fpsave(¤t->thread.fpu.hard);
500 last_task_used_math = NULL;
504 /* Copy from sh version */
505 childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;
509 if (user_mode(regs)) {
510 childregs->regs[15] = usp;
511 p->thread.uregs = childregs;
513 childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
516 childregs->regs[9] = 0; /* Set return value for child */
517 childregs->sr |= SR_FD; /* Invalidate FPU flag */
519 p->thread.sp = (unsigned long) childregs;
520 p->thread.pc = (unsigned long) ret_from_fork;
523 * Sign extend the edited stack.
524 * Note that thread.pc and thread.pc will stay
525 * 32-bit wide and context switch must take care
526 * of NEFF sign extension.
529 se = childregs->regs[15];
530 se = (se & NEFF_SIGN) ? (se | NEFF_MASK) : se;
531 childregs->regs[15] = se;
536 asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
537 unsigned long r4, unsigned long r5,
538 unsigned long r6, unsigned long r7,
539 struct pt_regs *pregs)
541 return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
544 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
545 unsigned long r4, unsigned long r5,
546 unsigned long r6, unsigned long r7,
547 struct pt_regs *pregs)
550 newsp = pregs->regs[15];
551 return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
555 * This is trivial, and on the face of it looks like it
556 * could equally well be done in user mode.
558 * Not so, for quite unobvious reasons - register pressure.
559 * In user mode vfork() cannot have a stack frame, and if
560 * done by calling the "clone()" system call directly, you
561 * do not have enough call-clobbered registers to hold all
562 * the information you need.
564 asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
565 unsigned long r4, unsigned long r5,
566 unsigned long r6, unsigned long r7,
567 struct pt_regs *pregs)
569 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
573 * sys_execve() executes a new program.
575 asmlinkage int sys_execve(char *ufilename, char **uargv,
576 char **uenvp, unsigned long r5,
577 unsigned long r6, unsigned long r7,
578 struct pt_regs *pregs)
584 filename = getname((char __user *)ufilename);
585 error = PTR_ERR(filename);
586 if (IS_ERR(filename))
589 error = do_execve(filename,
590 (char __user * __user *)uargv,
591 (char __user * __user *)uenvp,
595 current->ptrace &= ~PT_DTRACE;
596 task_unlock(current);
605 * These bracket the sleeping functions..
607 extern void interruptible_sleep_on(wait_queue_head_t *q);
609 #define mid_sched ((unsigned long) interruptible_sleep_on)
611 static int in_sh64_switch_to(unsigned long pc)
613 extern char __sh64_switch_to_end;
614 /* For a sleeping task, the PC is somewhere in the middle of the function,
615 so we don't have to worry about masking the LSB off */
616 return (pc >= (unsigned long) sh64_switch_to) &&
617 (pc < (unsigned long) &__sh64_switch_to_end);
620 unsigned long get_wchan(struct task_struct *p)
622 unsigned long schedule_fp;
623 unsigned long sh64_switch_to_fp;
624 unsigned long schedule_caller_pc;
627 if (!p || p == current || p->state == TASK_RUNNING)
631 * The same comment as on the Alpha applies here, too ...
633 pc = thread_saved_pc(p);
635 #ifdef CONFIG_FRAME_POINTER
636 if (in_sh64_switch_to(pc)) {
637 sh64_switch_to_fp = (long) p->thread.sp;
638 /* r14 is saved at offset 4 in the sh64_switch_to frame */
639 schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);
641 /* and the caller of 'schedule' is (currently!) saved at offset 24
642 in the frame of schedule (from disasm) */
643 schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
644 return schedule_caller_pc;
650 /* Provide a /proc/asids file that lists out the
651 ASIDs currently associated with the processes. (If the DM.PC register is
652 examined through the debug link, this shows ASID + PC. To make use of this,
653 the PID->ASID relationship needs to be known. This is primarily for
657 #if defined(CONFIG_SH64_PROC_ASIDS)
658 #include <linux/init.h>
659 #include <linux/proc_fs.h>
662 asids_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
665 struct task_struct *p;
666 read_lock(&tasklist_lock);
667 for_each_process(p) {
669 struct mm_struct *mm;
673 unsigned long asid, context;
674 context = mm->context;
675 asid = (context & 0xff);
676 len += sprintf(buf+len, "%5d : %02lx\n", pid, asid);
678 len += sprintf(buf+len, "%5d : (none)\n", pid);
681 read_unlock(&tasklist_lock);
686 static int __init register_proc_asids(void)
688 create_proc_read_entry("asids", 0, NULL, asids_proc_info, NULL);
692 __initcall(register_proc_asids);