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sh: Split out CPU topology initialization.
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CommitLineData
aec5e0e1
PM
1/*
2 * arch/sh/kernel/process.c
1da177e4 3 *
aec5e0e1 4 * This file handles the architecture-dependent parts of process handling..
1da177e4
LT
5 *
6 * Copyright (C) 1995 Linus Torvalds
7 *
8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
8ae91b9a 9 * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
3a2e117e 10 * Copyright (C) 2002 - 2007 Paul Mundt
1da177e4 11 */
1da177e4 12#include <linux/module.h>
1da177e4
LT
13#include <linux/mm.h>
14#include <linux/elfcore.h>
a3310bbd 15#include <linux/pm.h>
1da177e4 16#include <linux/kallsyms.h>
a3310bbd 17#include <linux/kexec.h>
b118ca57 18#include <linux/kdebug.h>
57be2b48 19#include <linux/tick.h>
1da177e4
LT
20#include <asm/uaccess.h>
21#include <asm/mmu_context.h>
5f8c9908 22#include <asm/pgalloc.h>
bd079997 23#include <asm/system.h>
b5233d07 24#include <asm/ubc.h>
1da177e4 25
aec5e0e1 26static int hlt_counter;
1da177e4
LT
27int ubc_usercnt = 0;
28
a3310bbd 29void (*pm_idle)(void);
a3310bbd
PM
30void (*pm_power_off)(void);
31EXPORT_SYMBOL(pm_power_off);
32
1da177e4
LT
33void disable_hlt(void)
34{
35 hlt_counter++;
36}
1da177e4
LT
37EXPORT_SYMBOL(disable_hlt);
38
39void enable_hlt(void)
40{
41 hlt_counter--;
42}
1da177e4
LT
43EXPORT_SYMBOL(enable_hlt);
44
f3a9022f
PM
45static int __init nohlt_setup(char *__unused)
46{
47 hlt_counter = 1;
48 return 1;
49}
50__setup("nohlt", nohlt_setup);
51
52static int __init hlt_setup(char *__unused)
53{
54 hlt_counter = 0;
55 return 1;
56}
57__setup("hlt", hlt_setup);
58
a3310bbd
PM
59void default_idle(void)
60{
f3a9022f
PM
61 if (!hlt_counter) {
62 clear_thread_flag(TIF_POLLING_NRFLAG);
63 smp_mb__after_clear_bit();
64 set_bl_bit();
65 while (!need_resched())
66 cpu_sleep();
67 clear_bl_bit();
68 set_thread_flag(TIF_POLLING_NRFLAG);
69 } else
70 while (!need_resched())
71 cpu_relax();
a3310bbd
PM
72}
73
64c7c8f8 74void cpu_idle(void)
1da177e4 75{
f3a9022f
PM
76 set_thread_flag(TIF_POLLING_NRFLAG);
77
1da177e4
LT
78 /* endless idle loop with no priority at all */
79 while (1) {
a3310bbd
PM
80 void (*idle)(void) = pm_idle;
81
82 if (!idle)
83 idle = default_idle;
84
57be2b48 85 tick_nohz_stop_sched_tick();
a3310bbd
PM
86 while (!need_resched())
87 idle();
57be2b48 88 tick_nohz_restart_sched_tick();
1da177e4 89
5bfb5d69 90 preempt_enable_no_resched();
1da177e4 91 schedule();
5bfb5d69 92 preempt_disable();
5f8c9908 93 check_pgt_cache();
1da177e4
LT
94 }
95}
96
1da177e4
LT
97void machine_restart(char * __unused)
98{
99 /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
100 asm volatile("ldc %0, sr\n\t"
101 "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
102}
103
1da177e4
LT
104void machine_halt(void)
105{
a3310bbd 106 local_irq_disable();
1da177e4 107
1da177e4
LT
108 while (1)
109 cpu_sleep();
110}
111
1da177e4
LT
112void machine_power_off(void)
113{
a3310bbd
PM
114 if (pm_power_off)
115 pm_power_off();
1da177e4
LT
116}
117
1da177e4
LT
118void show_regs(struct pt_regs * regs)
119{
120 printk("\n");
121 printk("Pid : %d, Comm: %20s\n", current->pid, current->comm);
6b002230 122 print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4
LT
123 printk("PC : %08lx SP : %08lx SR : %08lx ",
124 regs->pc, regs->regs[15], regs->sr);
125#ifdef CONFIG_MMU
126 printk("TEA : %08x ", ctrl_inl(MMU_TEA));
127#else
128 printk(" ");
129#endif
130 printk("%s\n", print_tainted());
131
132 printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
133 regs->regs[0],regs->regs[1],
134 regs->regs[2],regs->regs[3]);
135 printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
136 regs->regs[4],regs->regs[5],
137 regs->regs[6],regs->regs[7]);
138 printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
139 regs->regs[8],regs->regs[9],
140 regs->regs[10],regs->regs[11]);
141 printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
142 regs->regs[12],regs->regs[13],
143 regs->regs[14]);
144 printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
145 regs->mach, regs->macl, regs->gbr, regs->pr);
146
6b002230 147 show_trace(NULL, (unsigned long *)regs->regs[15], regs);
1da177e4
LT
148}
149
150/*
151 * Create a kernel thread
152 */
153
154/*
155 * This is the mechanism for creating a new kernel thread.
156 *
157 */
158extern void kernel_thread_helper(void);
159__asm__(".align 5\n"
160 "kernel_thread_helper:\n\t"
161 "jsr @r5\n\t"
162 " nop\n\t"
163 "mov.l 1f, r1\n\t"
164 "jsr @r1\n\t"
165 " mov r0, r4\n\t"
166 ".align 2\n\t"
167 "1:.long do_exit");
168
aec5e0e1 169/* Don't use this in BL=1(cli). Or else, CPU resets! */
1da177e4 170int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
aec5e0e1 171{
1da177e4
LT
172 struct pt_regs regs;
173
174 memset(&regs, 0, sizeof(regs));
aec5e0e1
PM
175 regs.regs[4] = (unsigned long)arg;
176 regs.regs[5] = (unsigned long)fn;
1da177e4 177
aec5e0e1 178 regs.pc = (unsigned long)kernel_thread_helper;
1da177e4
LT
179 regs.sr = (1 << 30);
180
181 /* Ok, create the new process.. */
aec5e0e1
PM
182 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
183 &regs, 0, NULL, NULL);
1da177e4
LT
184}
185
186/*
187 * Free current thread data structures etc..
188 */
189void exit_thread(void)
190{
191 if (current->thread.ubc_pc) {
192 current->thread.ubc_pc = 0;
193 ubc_usercnt -= 1;
194 }
195}
196
197void flush_thread(void)
198{
199#if defined(CONFIG_SH_FPU)
200 struct task_struct *tsk = current;
1da177e4 201 /* Forget lazy FPU state */
3cf0f4ec 202 clear_fpu(tsk, task_pt_regs(tsk));
1da177e4
LT
203 clear_used_math();
204#endif
205}
206
207void release_thread(struct task_struct *dead_task)
208{
209 /* do nothing */
210}
211
212/* Fill in the fpu structure for a core dump.. */
213int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
214{
215 int fpvalid = 0;
216
217#if defined(CONFIG_SH_FPU)
218 struct task_struct *tsk = current;
219
220 fpvalid = !!tsk_used_math(tsk);
221 if (fpvalid) {
222 unlazy_fpu(tsk, regs);
223 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
224 }
225#endif
226
227 return fpvalid;
228}
229
aec5e0e1 230/*
1da177e4
LT
231 * Capture the user space registers if the task is not running (in user space)
232 */
233int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
234{
235 struct pt_regs ptregs;
aec5e0e1 236
3cf0f4ec 237 ptregs = *task_pt_regs(tsk);
1da177e4
LT
238 elf_core_copy_regs(regs, &ptregs);
239
240 return 1;
241}
242
aec5e0e1 243int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpu)
1da177e4
LT
244{
245 int fpvalid = 0;
246
247#if defined(CONFIG_SH_FPU)
248 fpvalid = !!tsk_used_math(tsk);
249 if (fpvalid) {
3cf0f4ec 250 unlazy_fpu(tsk, task_pt_regs(tsk));
1da177e4
LT
251 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
252 }
253#endif
254
255 return fpvalid;
256}
257
258asmlinkage void ret_from_fork(void);
259
260int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
261 unsigned long unused,
262 struct task_struct *p, struct pt_regs *regs)
263{
2991be72 264 struct thread_info *ti = task_thread_info(p);
1da177e4
LT
265 struct pt_regs *childregs;
266#if defined(CONFIG_SH_FPU)
267 struct task_struct *tsk = current;
268
269 unlazy_fpu(tsk, regs);
270 p->thread.fpu = tsk->thread.fpu;
271 copy_to_stopped_child_used_math(p);
272#endif
273
3cf0f4ec 274 childregs = task_pt_regs(p);
1da177e4
LT
275 *childregs = *regs;
276
277 if (user_mode(regs)) {
278 childregs->regs[15] = usp;
2991be72 279 ti->addr_limit = USER_DS;
1da177e4 280 } else {
e6bcf562 281 childregs->regs[15] = (unsigned long)childregs;
2991be72 282 ti->addr_limit = KERNEL_DS;
1da177e4 283 }
aec5e0e1 284
e6bcf562 285 if (clone_flags & CLONE_SETTLS)
1da177e4 286 childregs->gbr = childregs->regs[0];
aec5e0e1 287
1da177e4
LT
288 childregs->regs[0] = 0; /* Set return value for child */
289
290 p->thread.sp = (unsigned long) childregs;
291 p->thread.pc = (unsigned long) ret_from_fork;
292
293 p->thread.ubc_pc = 0;
294
295 return 0;
296}
297
1da177e4 298/* Tracing by user break controller. */
aec5e0e1 299static void ubc_set_tracing(int asid, unsigned long pc)
1da177e4 300{
8ae91b9a
RS
301#if defined(CONFIG_CPU_SH4A)
302 unsigned long val;
303
304 val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE);
305 val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid));
306
307 ctrl_outl(val, UBC_CBR0);
308 ctrl_outl(pc, UBC_CAR0);
309 ctrl_outl(0x0, UBC_CAMR0);
310 ctrl_outl(0x0, UBC_CBCR);
311
312 val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE);
313 ctrl_outl(val, UBC_CRR0);
314
aec5e0e1 315 /* Read UBC register that we wrote last, for checking update */
8ae91b9a
RS
316 val = ctrl_inl(UBC_CRR0);
317
318#else /* CONFIG_CPU_SH4A */
1da177e4
LT
319 ctrl_outl(pc, UBC_BARA);
320
a2d1a5fa 321#ifdef CONFIG_MMU
1da177e4 322 /* We don't have any ASID settings for the SH-2! */
11c19656 323 if (current_cpu_data.type != CPU_SH7604)
1da177e4 324 ctrl_outb(asid, UBC_BASRA);
a2d1a5fa 325#endif
1da177e4
LT
326
327 ctrl_outl(0, UBC_BAMRA);
328
11c19656 329 if (current_cpu_data.type == CPU_SH7729 ||
3a2e117e
PM
330 current_cpu_data.type == CPU_SH7710 ||
331 current_cpu_data.type == CPU_SH7712) {
1da177e4
LT
332 ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA);
333 ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR);
334 } else {
335 ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA);
336 ctrl_outw(BRCR_PCBA, UBC_BRCR);
337 }
8ae91b9a 338#endif /* CONFIG_CPU_SH4A */
1da177e4
LT
339}
340
341/*
342 * switch_to(x,y) should switch tasks from x to y.
343 *
344 */
aec5e0e1
PM
345struct task_struct *__switch_to(struct task_struct *prev,
346 struct task_struct *next)
1da177e4
LT
347{
348#if defined(CONFIG_SH_FPU)
3cf0f4ec 349 unlazy_fpu(prev, task_pt_regs(prev));
1da177e4
LT
350#endif
351
352#ifdef CONFIG_PREEMPT
353 {
354 unsigned long flags;
355 struct pt_regs *regs;
356
357 local_irq_save(flags);
3cf0f4ec 358 regs = task_pt_regs(prev);
1da177e4
LT
359 if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
360 int offset = (int)regs->regs[15];
361
362 /* Reset stack pointer: clear critical region mark */
363 regs->regs[15] = regs->regs[1];
364 if (regs->pc < regs->regs[0])
365 /* Go to rewind point */
366 regs->pc = regs->regs[0] + offset;
367 }
368 local_irq_restore(flags);
369 }
370#endif
371
a2d1a5fa 372#ifdef CONFIG_MMU
1da177e4
LT
373 /*
374 * Restore the kernel mode register
aec5e0e1 375 * k7 (r7_bank1)
1da177e4
LT
376 */
377 asm volatile("ldc %0, r7_bank"
378 : /* no output */
cafcfcaa 379 : "r" (task_thread_info(next)));
a2d1a5fa 380#endif
1da177e4 381
1da177e4
LT
382 /* If no tasks are using the UBC, we're done */
383 if (ubc_usercnt == 0)
384 /* If no tasks are using the UBC, we're done */;
385 else if (next->thread.ubc_pc && next->mm) {
a2d1a5fa
YS
386 int asid = 0;
387#ifdef CONFIG_MMU
aec5e0e1 388 asid |= cpu_asid(smp_processor_id(), next->mm);
a2d1a5fa
YS
389#endif
390 ubc_set_tracing(asid, next->thread.ubc_pc);
1da177e4 391 } else {
8ae91b9a
RS
392#if defined(CONFIG_CPU_SH4A)
393 ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
394 ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
395#else
1da177e4
LT
396 ctrl_outw(0, UBC_BBRA);
397 ctrl_outw(0, UBC_BBRB);
8ae91b9a 398#endif
1da177e4 399 }
1da177e4
LT
400
401 return prev;
402}
403
404asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
405 unsigned long r6, unsigned long r7,
f0bc814c 406 struct pt_regs __regs)
1da177e4 407{
f0bc814c 408 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4 409#ifdef CONFIG_MMU
f0bc814c 410 return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
1da177e4
LT
411#else
412 /* fork almost works, enough to trick you into looking elsewhere :-( */
413 return -EINVAL;
414#endif
415}
416
417asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
418 unsigned long parent_tidptr,
419 unsigned long child_tidptr,
f0bc814c 420 struct pt_regs __regs)
1da177e4 421{
f0bc814c 422 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4 423 if (!newsp)
f0bc814c
SM
424 newsp = regs->regs[15];
425 return do_fork(clone_flags, newsp, regs, 0,
aec5e0e1
PM
426 (int __user *)parent_tidptr,
427 (int __user *)child_tidptr);
1da177e4
LT
428}
429
430/*
431 * This is trivial, and on the face of it looks like it
432 * could equally well be done in user mode.
433 *
434 * Not so, for quite unobvious reasons - register pressure.
435 * In user mode vfork() cannot have a stack frame, and if
436 * done by calling the "clone()" system call directly, you
437 * do not have enough call-clobbered registers to hold all
438 * the information you need.
439 */
440asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
441 unsigned long r6, unsigned long r7,
f0bc814c 442 struct pt_regs __regs)
1da177e4 443{
f0bc814c
SM
444 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
445 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
1da177e4
LT
446 0, NULL, NULL);
447}
448
449/*
450 * sys_execve() executes a new program.
451 */
452asmlinkage int sys_execve(char *ufilename, char **uargv,
453 char **uenvp, unsigned long r7,
f0bc814c 454 struct pt_regs __regs)
1da177e4 455{
f0bc814c 456 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4
LT
457 int error;
458 char *filename;
459
460 filename = getname((char __user *)ufilename);
461 error = PTR_ERR(filename);
462 if (IS_ERR(filename))
463 goto out;
464
465 error = do_execve(filename,
466 (char __user * __user *)uargv,
467 (char __user * __user *)uenvp,
f0bc814c 468 regs);
1da177e4
LT
469 if (error == 0) {
470 task_lock(current);
471 current->ptrace &= ~PT_DTRACE;
472 task_unlock(current);
473 }
474 putname(filename);
475out:
476 return error;
477}
478
479unsigned long get_wchan(struct task_struct *p)
480{
481 unsigned long schedule_frame;
482 unsigned long pc;
483
484 if (!p || p == current || p->state == TASK_RUNNING)
485 return 0;
486
487 /*
488 * The same comment as on the Alpha applies here, too ...
489 */
490 pc = thread_saved_pc(p);
491 if (in_sched_functions(pc)) {
b652c23c
PM
492 schedule_frame = (unsigned long)p->thread.sp;
493 return ((unsigned long *)schedule_frame)[21];
1da177e4 494 }
b652c23c 495
1da177e4
LT
496 return pc;
497}
498
f0bc814c 499asmlinkage void break_point_trap(void)
1da177e4
LT
500{
501 /* Clear tracing. */
8ae91b9a
RS
502#if defined(CONFIG_CPU_SH4A)
503 ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
504 ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
505#else
1da177e4
LT
506 ctrl_outw(0, UBC_BBRA);
507 ctrl_outw(0, UBC_BBRB);
8ae91b9a 508#endif
1da177e4
LT
509 current->thread.ubc_pc = 0;
510 ubc_usercnt -= 1;
511
512 force_sig(SIGTRAP, current);
513}
514
f413d0d9
PM
515/*
516 * Generic trap handler.
517 */
518asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5,
519 unsigned long r6, unsigned long r7,
520 struct pt_regs __regs)
521{
522 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
523
524 /* Rewind */
53f983a9 525 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
f413d0d9 526
b118ca57 527 if (notify_die(DIE_TRAP, "debug trap", regs, 0, regs->tra & 0xff,
3a2e117e
PM
528 SIGTRAP) == NOTIFY_STOP)
529 return;
530
f413d0d9
PM
531 force_sig(SIGTRAP, current);
532}
533
534/*
535 * Special handler for BUG() traps.
536 */
537asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5,
538 unsigned long r6, unsigned long r7,
539 struct pt_regs __regs)
1da177e4 540{
f0bc814c
SM
541 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
542
dc34d312 543 /* Rewind */
53f983a9 544 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
dc34d312 545
b118ca57 546 if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
3a2e117e
PM
547 SIGTRAP) == NOTIFY_STOP)
548 return;
549
dc34d312
PM
550#ifdef CONFIG_BUG
551 if (__kernel_text_address(instruction_pointer(regs))) {
552 u16 insn = *(u16 *)instruction_pointer(regs);
553 if (insn == TRAPA_BUG_OPCODE)
554 handle_BUG(regs);
555 }
556#endif
557
1da177e4
LT
558 force_sig(SIGTRAP, current);
559}