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authorPaul Mundt <lethal@linux-sh.org>2007-11-09 02:57:04 -0500
committerPaul Mundt <lethal@linux-sh.org>2008-01-27 23:18:42 -0500
commitfe51bc9eaf45253bd437907ed04031a93640ca69 (patch)
treec7faf184450049e166b2dc14564aa5b008660e27 /arch/sh/kernel/process_32.c
parent5055235554804b39c613ada76d7598c14265a00b (diff)
sh: Split out arch/sh/kernel/process.c for _32 and _64 variants.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/kernel/process_32.c')
-rw-r--r--arch/sh/kernel/process_32.c558
1 files changed, 558 insertions, 0 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
new file mode 100644
index 000000000000..6d7f2b07e491
--- /dev/null
+++ b/arch/sh/kernel/process_32.c
@@ -0,0 +1,558 @@
1/*
2 * arch/sh/kernel/process.c
3 *
4 * This file handles the architecture-dependent parts of process handling..
5 *
6 * Copyright (C) 1995 Linus Torvalds
7 *
8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
9 * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
10 * Copyright (C) 2002 - 2007 Paul Mundt
11 */
12#include <linux/module.h>
13#include <linux/mm.h>
14#include <linux/elfcore.h>
15#include <linux/pm.h>
16#include <linux/kallsyms.h>
17#include <linux/kexec.h>
18#include <linux/kdebug.h>
19#include <linux/tick.h>
20#include <linux/reboot.h>
21#include <linux/fs.h>
22#include <linux/preempt.h>
23#include <asm/uaccess.h>
24#include <asm/mmu_context.h>
25#include <asm/pgalloc.h>
26#include <asm/system.h>
27#include <asm/ubc.h>
28
29static int hlt_counter;
30int ubc_usercnt = 0;
31
32void (*pm_idle)(void);
33void (*pm_power_off)(void);
34EXPORT_SYMBOL(pm_power_off);
35
36void disable_hlt(void)
37{
38 hlt_counter++;
39}
40EXPORT_SYMBOL(disable_hlt);
41
42void enable_hlt(void)
43{
44 hlt_counter--;
45}
46EXPORT_SYMBOL(enable_hlt);
47
48static int __init nohlt_setup(char *__unused)
49{
50 hlt_counter = 1;
51 return 1;
52}
53__setup("nohlt", nohlt_setup);
54
55static int __init hlt_setup(char *__unused)
56{
57 hlt_counter = 0;
58 return 1;
59}
60__setup("hlt", hlt_setup);
61
62void default_idle(void)
63{
64 if (!hlt_counter) {
65 clear_thread_flag(TIF_POLLING_NRFLAG);
66 smp_mb__after_clear_bit();
67 set_bl_bit();
68 while (!need_resched())
69 cpu_sleep();
70 clear_bl_bit();
71 set_thread_flag(TIF_POLLING_NRFLAG);
72 } else
73 while (!need_resched())
74 cpu_relax();
75}
76
77void cpu_idle(void)
78{
79 set_thread_flag(TIF_POLLING_NRFLAG);
80
81 /* endless idle loop with no priority at all */
82 while (1) {
83 void (*idle)(void) = pm_idle;
84
85 if (!idle)
86 idle = default_idle;
87
88 tick_nohz_stop_sched_tick();
89 while (!need_resched())
90 idle();
91 tick_nohz_restart_sched_tick();
92
93 preempt_enable_no_resched();
94 schedule();
95 preempt_disable();
96 check_pgt_cache();
97 }
98}
99
100void machine_restart(char * __unused)
101{
102 /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
103 asm volatile("ldc %0, sr\n\t"
104 "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
105}
106
107void machine_halt(void)
108{
109 local_irq_disable();
110
111 while (1)
112 cpu_sleep();
113}
114
115void machine_power_off(void)
116{
117 if (pm_power_off)
118 pm_power_off();
119}
120
121void show_regs(struct pt_regs * regs)
122{
123 printk("\n");
124 printk("Pid : %d, Comm: %20s\n", task_pid_nr(current), current->comm);
125 print_symbol("PC is at %s\n", instruction_pointer(regs));
126 printk("PC : %08lx SP : %08lx SR : %08lx ",
127 regs->pc, regs->regs[15], regs->sr);
128#ifdef CONFIG_MMU
129 printk("TEA : %08x ", ctrl_inl(MMU_TEA));
130#else
131 printk(" ");
132#endif
133 printk("%s\n", print_tainted());
134
135 printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
136 regs->regs[0],regs->regs[1],
137 regs->regs[2],regs->regs[3]);
138 printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
139 regs->regs[4],regs->regs[5],
140 regs->regs[6],regs->regs[7]);
141 printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
142 regs->regs[8],regs->regs[9],
143 regs->regs[10],regs->regs[11]);
144 printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
145 regs->regs[12],regs->regs[13],
146 regs->regs[14]);
147 printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
148 regs->mach, regs->macl, regs->gbr, regs->pr);
149
150 show_trace(NULL, (unsigned long *)regs->regs[15], regs);
151}
152
153/*
154 * Create a kernel thread
155 */
156
157/*
158 * This is the mechanism for creating a new kernel thread.
159 *
160 */
161extern void kernel_thread_helper(void);
162__asm__(".align 5\n"
163 "kernel_thread_helper:\n\t"
164 "jsr @r5\n\t"
165 " nop\n\t"
166 "mov.l 1f, r1\n\t"
167 "jsr @r1\n\t"
168 " mov r0, r4\n\t"
169 ".align 2\n\t"
170 "1:.long do_exit");
171
172/* Don't use this in BL=1(cli). Or else, CPU resets! */
173int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
174{
175 struct pt_regs regs;
176
177 memset(&regs, 0, sizeof(regs));
178 regs.regs[4] = (unsigned long)arg;
179 regs.regs[5] = (unsigned long)fn;
180
181 regs.pc = (unsigned long)kernel_thread_helper;
182 regs.sr = (1 << 30);
183
184 /* Ok, create the new process.. */
185 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
186 &regs, 0, NULL, NULL);
187}
188
189/*
190 * Free current thread data structures etc..
191 */
192void exit_thread(void)
193{
194 if (current->thread.ubc_pc) {
195 current->thread.ubc_pc = 0;
196 ubc_usercnt -= 1;
197 }
198}
199
200void flush_thread(void)
201{
202#if defined(CONFIG_SH_FPU)
203 struct task_struct *tsk = current;
204 /* Forget lazy FPU state */
205 clear_fpu(tsk, task_pt_regs(tsk));
206 clear_used_math();
207#endif
208}
209
210void release_thread(struct task_struct *dead_task)
211{
212 /* do nothing */
213}
214
215/* Fill in the fpu structure for a core dump.. */
216int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
217{
218 int fpvalid = 0;
219
220#if defined(CONFIG_SH_FPU)
221 struct task_struct *tsk = current;
222
223 fpvalid = !!tsk_used_math(tsk);
224 if (fpvalid) {
225 unlazy_fpu(tsk, regs);
226 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
227 }
228#endif
229
230 return fpvalid;
231}
232
233/*
234 * Capture the user space registers if the task is not running (in user space)
235 */
236int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
237{
238 struct pt_regs ptregs;
239
240 ptregs = *task_pt_regs(tsk);
241 elf_core_copy_regs(regs, &ptregs);
242
243 return 1;
244}
245
246int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpu)
247{
248 int fpvalid = 0;
249
250#if defined(CONFIG_SH_FPU)
251 fpvalid = !!tsk_used_math(tsk);
252 if (fpvalid) {
253 unlazy_fpu(tsk, task_pt_regs(tsk));
254 memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
255 }
256#endif
257
258 return fpvalid;
259}
260
261asmlinkage void ret_from_fork(void);
262
263int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
264 unsigned long unused,
265 struct task_struct *p, struct pt_regs *regs)
266{
267 struct thread_info *ti = task_thread_info(p);
268 struct pt_regs *childregs;
269#if defined(CONFIG_SH_FPU)
270 struct task_struct *tsk = current;
271
272 unlazy_fpu(tsk, regs);
273 p->thread.fpu = tsk->thread.fpu;
274 copy_to_stopped_child_used_math(p);
275#endif
276
277 childregs = task_pt_regs(p);
278 *childregs = *regs;
279
280 if (user_mode(regs)) {
281 childregs->regs[15] = usp;
282 ti->addr_limit = USER_DS;
283 } else {
284 childregs->regs[15] = (unsigned long)childregs;
285 ti->addr_limit = KERNEL_DS;
286 }
287
288 if (clone_flags & CLONE_SETTLS)
289 childregs->gbr = childregs->regs[0];
290
291 childregs->regs[0] = 0; /* Set return value for child */
292
293 p->thread.sp = (unsigned long) childregs;
294 p->thread.pc = (unsigned long) ret_from_fork;
295
296 p->thread.ubc_pc = 0;
297
298 return 0;
299}
300
301/* Tracing by user break controller. */
302static void ubc_set_tracing(int asid, unsigned long pc)
303{
304#if defined(CONFIG_CPU_SH4A)
305 unsigned long val;
306
307 val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE);
308 val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid));
309
310 ctrl_outl(val, UBC_CBR0);
311 ctrl_outl(pc, UBC_CAR0);
312 ctrl_outl(0x0, UBC_CAMR0);
313 ctrl_outl(0x0, UBC_CBCR);
314
315 val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE);
316 ctrl_outl(val, UBC_CRR0);
317
318 /* Read UBC register that we wrote last, for checking update */
319 val = ctrl_inl(UBC_CRR0);
320
321#else /* CONFIG_CPU_SH4A */
322 ctrl_outl(pc, UBC_BARA);
323
324#ifdef CONFIG_MMU
325 ctrl_outb(asid, UBC_BASRA);
326#endif
327
328 ctrl_outl(0, UBC_BAMRA);
329
330 if (current_cpu_data.type == CPU_SH7729 ||
331 current_cpu_data.type == CPU_SH7710 ||
332 current_cpu_data.type == CPU_SH7712) {
333 ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA);
334 ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR);
335 } else {
336 ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA);
337 ctrl_outw(BRCR_PCBA, UBC_BRCR);
338 }
339#endif /* CONFIG_CPU_SH4A */
340}
341
342/*
343 * switch_to(x,y) should switch tasks from x to y.
344 *
345 */
346struct task_struct *__switch_to(struct task_struct *prev,
347 struct task_struct *next)
348{
349#if defined(CONFIG_SH_FPU)
350 unlazy_fpu(prev, task_pt_regs(prev));
351#endif
352
353#if defined(CONFIG_GUSA) && defined(CONFIG_PREEMPT)
354 {
355 struct pt_regs *regs;
356
357 preempt_disable();
358 regs = task_pt_regs(prev);
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 preempt_enable_no_resched();
369 }
370#endif
371
372#ifdef CONFIG_MMU
373 /*
374 * Restore the kernel mode register
375 * k7 (r7_bank1)
376 */
377 asm volatile("ldc %0, r7_bank"
378 : /* no output */
379 : "r" (task_thread_info(next)));
380#endif
381
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) {
386 int asid = 0;
387#ifdef CONFIG_MMU
388 asid |= cpu_asid(smp_processor_id(), next->mm);
389#endif
390 ubc_set_tracing(asid, next->thread.ubc_pc);
391 } else {
392#if defined(CONFIG_CPU_SH4A)
393 ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
394 ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
395#else
396 ctrl_outw(0, UBC_BBRA);
397 ctrl_outw(0, UBC_BBRB);
398#endif
399 }
400
401 return prev;
402}
403
404asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
405 unsigned long r6, unsigned long r7,
406 struct pt_regs __regs)
407{
408#ifdef CONFIG_MMU
409 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
410 return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
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,
420 struct pt_regs __regs)
421{
422 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
423 if (!newsp)
424 newsp = regs->regs[15];
425 return do_fork(clone_flags, newsp, regs, 0,
426 (int __user *)parent_tidptr,
427 (int __user *)child_tidptr);
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,
442 struct pt_regs __regs)
443{
444 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
445 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
446 0, NULL, NULL);
447}
448
449/*
450 * sys_execve() executes a new program.
451 */
452asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv,
453 char __user * __user *uenvp, unsigned long r7,
454 struct pt_regs __regs)
455{
456 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
457 int error;
458 char *filename;
459
460 filename = getname(ufilename);
461 error = PTR_ERR(filename);
462 if (IS_ERR(filename))
463 goto out;
464
465 error = do_execve(filename, uargv, uenvp, regs);
466 if (error == 0) {
467 task_lock(current);
468 current->ptrace &= ~PT_DTRACE;
469 task_unlock(current);
470 }
471 putname(filename);
472out:
473 return error;
474}
475
476unsigned long get_wchan(struct task_struct *p)
477{
478 unsigned long pc;
479
480 if (!p || p == current || p->state == TASK_RUNNING)
481 return 0;
482
483 /*
484 * The same comment as on the Alpha applies here, too ...
485 */
486 pc = thread_saved_pc(p);
487
488#ifdef CONFIG_FRAME_POINTER
489 if (in_sched_functions(pc)) {
490 unsigned long schedule_frame = (unsigned long)p->thread.sp;
491 return ((unsigned long *)schedule_frame)[21];
492 }
493#endif
494
495 return pc;
496}
497
498asmlinkage void break_point_trap(void)
499{
500 /* Clear tracing. */
501#if defined(CONFIG_CPU_SH4A)
502 ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
503 ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
504#else
505 ctrl_outw(0, UBC_BBRA);
506 ctrl_outw(0, UBC_BBRB);
507#endif
508 current->thread.ubc_pc = 0;
509 ubc_usercnt -= 1;
510
511 force_sig(SIGTRAP, current);
512}
513
514/*
515 * Generic trap handler.
516 */
517asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5,
518 unsigned long r6, unsigned long r7,
519 struct pt_regs __regs)
520{
521 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
522
523 /* Rewind */
524 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
525
526 if (notify_die(DIE_TRAP, "debug trap", regs, 0, regs->tra & 0xff,
527 SIGTRAP) == NOTIFY_STOP)
528 return;
529
530 force_sig(SIGTRAP, current);
531}
532
533/*
534 * Special handler for BUG() traps.
535 */
536asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5,
537 unsigned long r6, unsigned long r7,
538 struct pt_regs __regs)
539{
540 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
541
542 /* Rewind */
543 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
544
545 if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
546 SIGTRAP) == NOTIFY_STOP)
547 return;
548
549#ifdef CONFIG_BUG
550 if (__kernel_text_address(instruction_pointer(regs))) {
551 u16 insn = *(u16 *)instruction_pointer(regs);
552 if (insn == TRAPA_BUG_OPCODE)
553 handle_BUG(regs);
554 }
555#endif
556
557 force_sig(SIGTRAP, current);
558}