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-rw-r--r--arch/arm/kernel/process.c460
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diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
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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
36extern const char *processor_modes[];
37extern void setup_mm_for_reboot(char mode);
38
39static volatile int hlt_counter;
40
41#include <asm/arch/system.h>
42
43void disable_hlt(void)
44{
45 hlt_counter++;
46}
47
48EXPORT_SYMBOL(disable_hlt);
49
50void enable_hlt(void)
51{
52 hlt_counter--;
53}
54
55EXPORT_SYMBOL(enable_hlt);
56
57static int __init nohlt_setup(char *__unused)
58{
59 hlt_counter = 1;
60 return 1;
61}
62
63static 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 */
75void (*pm_idle)(void);
76EXPORT_SYMBOL(pm_idle);
77
78void (*pm_power_off)(void);
79EXPORT_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 */
85void 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 */
98void 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
117static char reboot_mode = 'h';
118
119int __init reboot_setup(char *str)
120{
121 reboot_mode = str[0];
122 return 1;
123}
124
125__setup("reboot=", reboot_setup);
126
127void machine_halt(void)
128{
129}
130
131EXPORT_SYMBOL(machine_halt);
132
133void machine_power_off(void)
134{
135 if (pm_power_off)
136 pm_power_off();
137}
138
139EXPORT_SYMBOL(machine_power_off);
140
141void 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
169EXPORT_SYMBOL(machine_restart);
170
171void 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
216void 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 */
248static unsigned long *thread_info_head;
249static 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
255struct 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
285void 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 */
299void exit_thread(void)
300{
301}
302
303static void default_fp_init(union fp_state *fp)
304{
305 memset(fp, 0, sizeof(union fp_state));
306}
307
308void (*fp_init)(union fp_state *) = default_fp_init;
309EXPORT_SYMBOL(fp_init);
310
311void 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
327void 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
337asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
338
339int
340copy_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 */
364int 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}
374EXPORT_SYMBOL(dump_fpu);
375
376/*
377 * fill in the user structure for a core dump..
378 */
379void 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}
403EXPORT_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 */
410extern void kernel_thread_helper(void);
411asm( ".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 */
424pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
425{
426 struct pt_regs regs;
427
428 memset(&regs, 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, &regs, 0, NULL, NULL);
437}
438EXPORT_SYMBOL(kernel_thread);
439
440unsigned 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}
460EXPORT_SYMBOL(get_wchan);