diff options
Diffstat (limited to 'arch/arm/kernel/process.c')
-rw-r--r-- | arch/arm/kernel/process.c | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c new file mode 100644 index 000000000000..dbd8ca89b385 --- /dev/null +++ b/arch/arm/kernel/process.c | |||
@@ -0,0 +1,460 @@ | |||
1 | /* | ||
2 | * linux/arch/arm/kernel/process.c | ||
3 | * | ||
4 | * Copyright (C) 1996-2000 Russell King - Converted to ARM. | ||
5 | * Original Copyright (C) 1995 Linus Torvalds | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License version 2 as | ||
9 | * published by the Free Software Foundation. | ||
10 | */ | ||
11 | #include <stdarg.h> | ||
12 | |||
13 | #include <linux/config.h> | ||
14 | #include <linux/module.h> | ||
15 | #include <linux/sched.h> | ||
16 | #include <linux/kernel.h> | ||
17 | #include <linux/mm.h> | ||
18 | #include <linux/stddef.h> | ||
19 | #include <linux/unistd.h> | ||
20 | #include <linux/ptrace.h> | ||
21 | #include <linux/slab.h> | ||
22 | #include <linux/user.h> | ||
23 | #include <linux/a.out.h> | ||
24 | #include <linux/delay.h> | ||
25 | #include <linux/reboot.h> | ||
26 | #include <linux/interrupt.h> | ||
27 | #include <linux/kallsyms.h> | ||
28 | #include <linux/init.h> | ||
29 | |||
30 | #include <asm/system.h> | ||
31 | #include <asm/io.h> | ||
32 | #include <asm/leds.h> | ||
33 | #include <asm/processor.h> | ||
34 | #include <asm/uaccess.h> | ||
35 | |||
36 | extern const char *processor_modes[]; | ||
37 | extern void setup_mm_for_reboot(char mode); | ||
38 | |||
39 | static volatile int hlt_counter; | ||
40 | |||
41 | #include <asm/arch/system.h> | ||
42 | |||
43 | void disable_hlt(void) | ||
44 | { | ||
45 | hlt_counter++; | ||
46 | } | ||
47 | |||
48 | EXPORT_SYMBOL(disable_hlt); | ||
49 | |||
50 | void enable_hlt(void) | ||
51 | { | ||
52 | hlt_counter--; | ||
53 | } | ||
54 | |||
55 | EXPORT_SYMBOL(enable_hlt); | ||
56 | |||
57 | static int __init nohlt_setup(char *__unused) | ||
58 | { | ||
59 | hlt_counter = 1; | ||
60 | return 1; | ||
61 | } | ||
62 | |||
63 | static int __init hlt_setup(char *__unused) | ||
64 | { | ||
65 | hlt_counter = 0; | ||
66 | return 1; | ||
67 | } | ||
68 | |||
69 | __setup("nohlt", nohlt_setup); | ||
70 | __setup("hlt", hlt_setup); | ||
71 | |||
72 | /* | ||
73 | * The following aren't currently used. | ||
74 | */ | ||
75 | void (*pm_idle)(void); | ||
76 | EXPORT_SYMBOL(pm_idle); | ||
77 | |||
78 | void (*pm_power_off)(void); | ||
79 | EXPORT_SYMBOL(pm_power_off); | ||
80 | |||
81 | /* | ||
82 | * This is our default idle handler. We need to disable | ||
83 | * interrupts here to ensure we don't miss a wakeup call. | ||
84 | */ | ||
85 | void default_idle(void) | ||
86 | { | ||
87 | local_irq_disable(); | ||
88 | if (!need_resched() && !hlt_counter) | ||
89 | arch_idle(); | ||
90 | local_irq_enable(); | ||
91 | } | ||
92 | |||
93 | /* | ||
94 | * The idle thread. We try to conserve power, while trying to keep | ||
95 | * overall latency low. The architecture specific idle is passed | ||
96 | * a value to indicate the level of "idleness" of the system. | ||
97 | */ | ||
98 | void cpu_idle(void) | ||
99 | { | ||
100 | local_fiq_enable(); | ||
101 | |||
102 | /* endless idle loop with no priority at all */ | ||
103 | while (1) { | ||
104 | void (*idle)(void) = pm_idle; | ||
105 | if (!idle) | ||
106 | idle = default_idle; | ||
107 | preempt_disable(); | ||
108 | leds_event(led_idle_start); | ||
109 | while (!need_resched()) | ||
110 | idle(); | ||
111 | leds_event(led_idle_end); | ||
112 | preempt_enable(); | ||
113 | schedule(); | ||
114 | } | ||
115 | } | ||
116 | |||
117 | static char reboot_mode = 'h'; | ||
118 | |||
119 | int __init reboot_setup(char *str) | ||
120 | { | ||
121 | reboot_mode = str[0]; | ||
122 | return 1; | ||
123 | } | ||
124 | |||
125 | __setup("reboot=", reboot_setup); | ||
126 | |||
127 | void machine_halt(void) | ||
128 | { | ||
129 | } | ||
130 | |||
131 | EXPORT_SYMBOL(machine_halt); | ||
132 | |||
133 | void machine_power_off(void) | ||
134 | { | ||
135 | if (pm_power_off) | ||
136 | pm_power_off(); | ||
137 | } | ||
138 | |||
139 | EXPORT_SYMBOL(machine_power_off); | ||
140 | |||
141 | void machine_restart(char * __unused) | ||
142 | { | ||
143 | /* | ||
144 | * Clean and disable cache, and turn off interrupts | ||
145 | */ | ||
146 | cpu_proc_fin(); | ||
147 | |||
148 | /* | ||
149 | * Tell the mm system that we are going to reboot - | ||
150 | * we may need it to insert some 1:1 mappings so that | ||
151 | * soft boot works. | ||
152 | */ | ||
153 | setup_mm_for_reboot(reboot_mode); | ||
154 | |||
155 | /* | ||
156 | * Now call the architecture specific reboot code. | ||
157 | */ | ||
158 | arch_reset(reboot_mode); | ||
159 | |||
160 | /* | ||
161 | * Whoops - the architecture was unable to reboot. | ||
162 | * Tell the user! | ||
163 | */ | ||
164 | mdelay(1000); | ||
165 | printk("Reboot failed -- System halted\n"); | ||
166 | while (1); | ||
167 | } | ||
168 | |||
169 | EXPORT_SYMBOL(machine_restart); | ||
170 | |||
171 | void show_regs(struct pt_regs * regs) | ||
172 | { | ||
173 | unsigned long flags; | ||
174 | |||
175 | flags = condition_codes(regs); | ||
176 | |||
177 | print_symbol("PC is at %s\n", instruction_pointer(regs)); | ||
178 | print_symbol("LR is at %s\n", regs->ARM_lr); | ||
179 | printk("pc : [<%08lx>] lr : [<%08lx>] %s\n" | ||
180 | "sp : %08lx ip : %08lx fp : %08lx\n", | ||
181 | instruction_pointer(regs), | ||
182 | regs->ARM_lr, print_tainted(), regs->ARM_sp, | ||
183 | regs->ARM_ip, regs->ARM_fp); | ||
184 | printk("r10: %08lx r9 : %08lx r8 : %08lx\n", | ||
185 | regs->ARM_r10, regs->ARM_r9, | ||
186 | regs->ARM_r8); | ||
187 | printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", | ||
188 | regs->ARM_r7, regs->ARM_r6, | ||
189 | regs->ARM_r5, regs->ARM_r4); | ||
190 | printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", | ||
191 | regs->ARM_r3, regs->ARM_r2, | ||
192 | regs->ARM_r1, regs->ARM_r0); | ||
193 | printk("Flags: %c%c%c%c", | ||
194 | flags & PSR_N_BIT ? 'N' : 'n', | ||
195 | flags & PSR_Z_BIT ? 'Z' : 'z', | ||
196 | flags & PSR_C_BIT ? 'C' : 'c', | ||
197 | flags & PSR_V_BIT ? 'V' : 'v'); | ||
198 | printk(" IRQs o%s FIQs o%s Mode %s%s Segment %s\n", | ||
199 | interrupts_enabled(regs) ? "n" : "ff", | ||
200 | fast_interrupts_enabled(regs) ? "n" : "ff", | ||
201 | processor_modes[processor_mode(regs)], | ||
202 | thumb_mode(regs) ? " (T)" : "", | ||
203 | get_fs() == get_ds() ? "kernel" : "user"); | ||
204 | { | ||
205 | unsigned int ctrl, transbase, dac; | ||
206 | __asm__ ( | ||
207 | " mrc p15, 0, %0, c1, c0\n" | ||
208 | " mrc p15, 0, %1, c2, c0\n" | ||
209 | " mrc p15, 0, %2, c3, c0\n" | ||
210 | : "=r" (ctrl), "=r" (transbase), "=r" (dac)); | ||
211 | printk("Control: %04X Table: %08X DAC: %08X\n", | ||
212 | ctrl, transbase, dac); | ||
213 | } | ||
214 | } | ||
215 | |||
216 | void show_fpregs(struct user_fp *regs) | ||
217 | { | ||
218 | int i; | ||
219 | |||
220 | for (i = 0; i < 8; i++) { | ||
221 | unsigned long *p; | ||
222 | char type; | ||
223 | |||
224 | p = (unsigned long *)(regs->fpregs + i); | ||
225 | |||
226 | switch (regs->ftype[i]) { | ||
227 | case 1: type = 'f'; break; | ||
228 | case 2: type = 'd'; break; | ||
229 | case 3: type = 'e'; break; | ||
230 | default: type = '?'; break; | ||
231 | } | ||
232 | if (regs->init_flag) | ||
233 | type = '?'; | ||
234 | |||
235 | printk(" f%d(%c): %08lx %08lx %08lx%c", | ||
236 | i, type, p[0], p[1], p[2], i & 1 ? '\n' : ' '); | ||
237 | } | ||
238 | |||
239 | |||
240 | printk("FPSR: %08lx FPCR: %08lx\n", | ||
241 | (unsigned long)regs->fpsr, | ||
242 | (unsigned long)regs->fpcr); | ||
243 | } | ||
244 | |||
245 | /* | ||
246 | * Task structure and kernel stack allocation. | ||
247 | */ | ||
248 | static unsigned long *thread_info_head; | ||
249 | static unsigned int nr_thread_info; | ||
250 | |||
251 | #define EXTRA_TASK_STRUCT 4 | ||
252 | #define ll_alloc_task_struct() ((struct thread_info *) __get_free_pages(GFP_KERNEL,1)) | ||
253 | #define ll_free_task_struct(p) free_pages((unsigned long)(p),1) | ||
254 | |||
255 | struct thread_info *alloc_thread_info(struct task_struct *task) | ||
256 | { | ||
257 | struct thread_info *thread = NULL; | ||
258 | |||
259 | if (EXTRA_TASK_STRUCT) { | ||
260 | unsigned long *p = thread_info_head; | ||
261 | |||
262 | if (p) { | ||
263 | thread_info_head = (unsigned long *)p[0]; | ||
264 | nr_thread_info -= 1; | ||
265 | } | ||
266 | thread = (struct thread_info *)p; | ||
267 | } | ||
268 | |||
269 | if (!thread) | ||
270 | thread = ll_alloc_task_struct(); | ||
271 | |||
272 | #ifdef CONFIG_MAGIC_SYSRQ | ||
273 | /* | ||
274 | * The stack must be cleared if you want SYSRQ-T to | ||
275 | * give sensible stack usage information | ||
276 | */ | ||
277 | if (thread) { | ||
278 | char *p = (char *)thread; | ||
279 | memzero(p+KERNEL_STACK_SIZE, KERNEL_STACK_SIZE); | ||
280 | } | ||
281 | #endif | ||
282 | return thread; | ||
283 | } | ||
284 | |||
285 | void free_thread_info(struct thread_info *thread) | ||
286 | { | ||
287 | if (EXTRA_TASK_STRUCT && nr_thread_info < EXTRA_TASK_STRUCT) { | ||
288 | unsigned long *p = (unsigned long *)thread; | ||
289 | p[0] = (unsigned long)thread_info_head; | ||
290 | thread_info_head = p; | ||
291 | nr_thread_info += 1; | ||
292 | } else | ||
293 | ll_free_task_struct(thread); | ||
294 | } | ||
295 | |||
296 | /* | ||
297 | * Free current thread data structures etc.. | ||
298 | */ | ||
299 | void exit_thread(void) | ||
300 | { | ||
301 | } | ||
302 | |||
303 | static void default_fp_init(union fp_state *fp) | ||
304 | { | ||
305 | memset(fp, 0, sizeof(union fp_state)); | ||
306 | } | ||
307 | |||
308 | void (*fp_init)(union fp_state *) = default_fp_init; | ||
309 | EXPORT_SYMBOL(fp_init); | ||
310 | |||
311 | void flush_thread(void) | ||
312 | { | ||
313 | struct thread_info *thread = current_thread_info(); | ||
314 | struct task_struct *tsk = current; | ||
315 | |||
316 | memset(thread->used_cp, 0, sizeof(thread->used_cp)); | ||
317 | memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); | ||
318 | #if defined(CONFIG_IWMMXT) | ||
319 | iwmmxt_task_release(thread); | ||
320 | #endif | ||
321 | fp_init(&thread->fpstate); | ||
322 | #if defined(CONFIG_VFP) | ||
323 | vfp_flush_thread(&thread->vfpstate); | ||
324 | #endif | ||
325 | } | ||
326 | |||
327 | void release_thread(struct task_struct *dead_task) | ||
328 | { | ||
329 | #if defined(CONFIG_VFP) | ||
330 | vfp_release_thread(&dead_task->thread_info->vfpstate); | ||
331 | #endif | ||
332 | #if defined(CONFIG_IWMMXT) | ||
333 | iwmmxt_task_release(dead_task->thread_info); | ||
334 | #endif | ||
335 | } | ||
336 | |||
337 | asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); | ||
338 | |||
339 | int | ||
340 | copy_thread(int nr, unsigned long clone_flags, unsigned long stack_start, | ||
341 | unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs) | ||
342 | { | ||
343 | struct thread_info *thread = p->thread_info; | ||
344 | struct pt_regs *childregs; | ||
345 | |||
346 | childregs = ((struct pt_regs *)((unsigned long)thread + THREAD_SIZE - 8)) - 1; | ||
347 | *childregs = *regs; | ||
348 | childregs->ARM_r0 = 0; | ||
349 | childregs->ARM_sp = stack_start; | ||
350 | |||
351 | memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); | ||
352 | thread->cpu_context.sp = (unsigned long)childregs; | ||
353 | thread->cpu_context.pc = (unsigned long)ret_from_fork; | ||
354 | |||
355 | if (clone_flags & CLONE_SETTLS) | ||
356 | thread->tp_value = regs->ARM_r3; | ||
357 | |||
358 | return 0; | ||
359 | } | ||
360 | |||
361 | /* | ||
362 | * fill in the fpe structure for a core dump... | ||
363 | */ | ||
364 | int dump_fpu (struct pt_regs *regs, struct user_fp *fp) | ||
365 | { | ||
366 | struct thread_info *thread = current_thread_info(); | ||
367 | int used_math = thread->used_cp[1] | thread->used_cp[2]; | ||
368 | |||
369 | if (used_math) | ||
370 | memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); | ||
371 | |||
372 | return used_math != 0; | ||
373 | } | ||
374 | EXPORT_SYMBOL(dump_fpu); | ||
375 | |||
376 | /* | ||
377 | * fill in the user structure for a core dump.. | ||
378 | */ | ||
379 | void dump_thread(struct pt_regs * regs, struct user * dump) | ||
380 | { | ||
381 | struct task_struct *tsk = current; | ||
382 | |||
383 | dump->magic = CMAGIC; | ||
384 | dump->start_code = tsk->mm->start_code; | ||
385 | dump->start_stack = regs->ARM_sp & ~(PAGE_SIZE - 1); | ||
386 | |||
387 | dump->u_tsize = (tsk->mm->end_code - tsk->mm->start_code) >> PAGE_SHIFT; | ||
388 | dump->u_dsize = (tsk->mm->brk - tsk->mm->start_data + PAGE_SIZE - 1) >> PAGE_SHIFT; | ||
389 | dump->u_ssize = 0; | ||
390 | |||
391 | dump->u_debugreg[0] = tsk->thread.debug.bp[0].address; | ||
392 | dump->u_debugreg[1] = tsk->thread.debug.bp[1].address; | ||
393 | dump->u_debugreg[2] = tsk->thread.debug.bp[0].insn.arm; | ||
394 | dump->u_debugreg[3] = tsk->thread.debug.bp[1].insn.arm; | ||
395 | dump->u_debugreg[4] = tsk->thread.debug.nsaved; | ||
396 | |||
397 | if (dump->start_stack < 0x04000000) | ||
398 | dump->u_ssize = (0x04000000 - dump->start_stack) >> PAGE_SHIFT; | ||
399 | |||
400 | dump->regs = *regs; | ||
401 | dump->u_fpvalid = dump_fpu (regs, &dump->u_fp); | ||
402 | } | ||
403 | EXPORT_SYMBOL(dump_thread); | ||
404 | |||
405 | /* | ||
406 | * Shuffle the argument into the correct register before calling the | ||
407 | * thread function. r1 is the thread argument, r2 is the pointer to | ||
408 | * the thread function, and r3 points to the exit function. | ||
409 | */ | ||
410 | extern void kernel_thread_helper(void); | ||
411 | asm( ".section .text\n" | ||
412 | " .align\n" | ||
413 | " .type kernel_thread_helper, #function\n" | ||
414 | "kernel_thread_helper:\n" | ||
415 | " mov r0, r1\n" | ||
416 | " mov lr, r3\n" | ||
417 | " mov pc, r2\n" | ||
418 | " .size kernel_thread_helper, . - kernel_thread_helper\n" | ||
419 | " .previous"); | ||
420 | |||
421 | /* | ||
422 | * Create a kernel thread. | ||
423 | */ | ||
424 | pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) | ||
425 | { | ||
426 | struct pt_regs regs; | ||
427 | |||
428 | memset(®s, 0, sizeof(regs)); | ||
429 | |||
430 | regs.ARM_r1 = (unsigned long)arg; | ||
431 | regs.ARM_r2 = (unsigned long)fn; | ||
432 | regs.ARM_r3 = (unsigned long)do_exit; | ||
433 | regs.ARM_pc = (unsigned long)kernel_thread_helper; | ||
434 | regs.ARM_cpsr = SVC_MODE; | ||
435 | |||
436 | return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); | ||
437 | } | ||
438 | EXPORT_SYMBOL(kernel_thread); | ||
439 | |||
440 | unsigned long get_wchan(struct task_struct *p) | ||
441 | { | ||
442 | unsigned long fp, lr; | ||
443 | unsigned long stack_page; | ||
444 | int count = 0; | ||
445 | if (!p || p == current || p->state == TASK_RUNNING) | ||
446 | return 0; | ||
447 | |||
448 | stack_page = 4096 + (unsigned long)p->thread_info; | ||
449 | fp = thread_saved_fp(p); | ||
450 | do { | ||
451 | if (fp < stack_page || fp > 4092+stack_page) | ||
452 | return 0; | ||
453 | lr = pc_pointer (((unsigned long *)fp)[-1]); | ||
454 | if (!in_sched_functions(lr)) | ||
455 | return lr; | ||
456 | fp = *(unsigned long *) (fp - 12); | ||
457 | } while (count ++ < 16); | ||
458 | return 0; | ||
459 | } | ||
460 | EXPORT_SYMBOL(get_wchan); | ||