2 * linux/arch/arm/kernel/process.c
4 * Copyright (C) 1996-2000 Russell King - Converted to ARM.
5 * Original Copyright (C) 1995 Linus Torvalds
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.
13 #include <linux/module.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
17 #include <linux/stddef.h>
18 #include <linux/unistd.h>
19 #include <linux/ptrace.h>
20 #include <linux/slab.h>
21 #include <linux/user.h>
22 #include <linux/a.out.h>
23 #include <linux/delay.h>
24 #include <linux/reboot.h>
25 #include <linux/interrupt.h>
26 #include <linux/kallsyms.h>
27 #include <linux/init.h>
28 #include <linux/cpu.h>
29 #include <linux/elfcore.h>
33 #include <asm/processor.h>
34 #include <asm/system.h>
35 #include <asm/thread_notify.h>
36 #include <asm/uaccess.h>
37 #include <asm/mach/time.h>
39 extern const char *processor_modes
[];
40 extern void setup_mm_for_reboot(char mode
);
42 static volatile int hlt_counter
;
44 #include <asm/arch/system.h>
46 void disable_hlt(void)
51 EXPORT_SYMBOL(disable_hlt
);
58 EXPORT_SYMBOL(enable_hlt
);
60 static int __init
nohlt_setup(char *__unused
)
66 static int __init
hlt_setup(char *__unused
)
72 __setup("nohlt", nohlt_setup
);
73 __setup("hlt", hlt_setup
);
75 void arm_machine_restart(char mode
)
78 * Clean and disable cache, and turn off interrupts
83 * Tell the mm system that we are going to reboot -
84 * we may need it to insert some 1:1 mappings so that
87 setup_mm_for_reboot(mode
);
90 * Now call the architecture specific reboot code.
95 * Whoops - the architecture was unable to reboot.
99 printk("Reboot failed -- System halted\n");
104 * Function pointers to optional machine specific functions
106 void (*pm_idle
)(void);
107 EXPORT_SYMBOL(pm_idle
);
109 void (*pm_power_off
)(void);
110 EXPORT_SYMBOL(pm_power_off
);
112 void (*arm_pm_restart
)(char str
) = arm_machine_restart
;
113 EXPORT_SYMBOL_GPL(arm_pm_restart
);
117 * This is our default idle handler. We need to disable
118 * interrupts here to ensure we don't miss a wakeup call.
120 static void default_idle(void)
126 if (!need_resched()) {
127 timer_dyn_reprogram();
135 * The idle thread. We try to conserve power, while trying to keep
136 * overall latency low. The architecture specific idle is passed
137 * a value to indicate the level of "idleness" of the system.
143 /* endless idle loop with no priority at all */
145 void (*idle
)(void) = pm_idle
;
147 #ifdef CONFIG_HOTPLUG_CPU
148 if (cpu_is_offline(smp_processor_id())) {
149 leds_event(led_idle_start
);
156 leds_event(led_idle_start
);
157 while (!need_resched())
159 leds_event(led_idle_end
);
160 preempt_enable_no_resched();
166 static char reboot_mode
= 'h';
168 int __init
reboot_setup(char *str
)
170 reboot_mode
= str
[0];
174 __setup("reboot=", reboot_setup
);
176 #if 1 // add by Victor Yu. 03-06-2007
177 #if defined(CONFIG_ARCH_W311_TEST) // add by Victor Yu. 07-10-2008
178 #define SW_READY_LED_OFF() *(volatile unsigned int *)(CPE_GPIO_BASE) |= (1<<4)
180 #define SW_READY_LED_OFF() *(volatile unsigned int *)(CPE_GPIO_BASE) |= (1<<27)
183 void machine_halt(void)
185 SW_READY_LED_OFF(); // add by Victor Yu. 03-06-2007
186 while ( 1 ); // add by Victor Yu. 02-08-2007
190 void machine_power_off(void)
194 SW_READY_LED_OFF(); // add by Victor Yu. 03-06-2007
195 while ( 1 ); // add by Victor Yu. 02-08-2007
198 void machine_restart(char * __unused
)
201 * Clean and disable cache, and turn off interrupts
207 * Tell the mm system that we are going to reboot -
208 * we may need it to insert some 1:1 mappings so that
211 setup_mm_for_reboot(reboot_mode
);
215 * Now call the architecture specific reboot code.
217 SW_READY_LED_OFF(); // add by Victor Yu. 03-06-2007
218 arch_reset(reboot_mode
);
221 * Whoops - the architecture was unable to reboot.
225 printk("Reboot failed -- System halted\n");
229 void __show_regs(struct pt_regs
*regs
)
231 unsigned long flags
= condition_codes(regs
);
233 printk("CPU: %d\n", smp_processor_id());
234 print_symbol("PC is at %s\n", instruction_pointer(regs
));
235 print_symbol("LR is at %s\n", regs
->ARM_lr
);
236 printk("pc : [<%08lx>] lr : [<%08lx>] %s\n"
237 "sp : %08lx ip : %08lx fp : %08lx\n",
238 instruction_pointer(regs
),
239 regs
->ARM_lr
, print_tainted(), regs
->ARM_sp
,
240 regs
->ARM_ip
, regs
->ARM_fp
);
241 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
242 regs
->ARM_r10
, regs
->ARM_r9
,
244 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
245 regs
->ARM_r7
, regs
->ARM_r6
,
246 regs
->ARM_r5
, regs
->ARM_r4
);
247 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
248 regs
->ARM_r3
, regs
->ARM_r2
,
249 regs
->ARM_r1
, regs
->ARM_r0
);
250 printk("Flags: %c%c%c%c",
251 flags
& PSR_N_BIT
? 'N' : 'n',
252 flags
& PSR_Z_BIT
? 'Z' : 'z',
253 flags
& PSR_C_BIT
? 'C' : 'c',
254 flags
& PSR_V_BIT
? 'V' : 'v');
255 printk(" IRQs o%s FIQs o%s Mode %s%s Segment %s\n",
256 interrupts_enabled(regs
) ? "n" : "ff",
257 fast_interrupts_enabled(regs
) ? "n" : "ff",
258 processor_modes
[processor_mode(regs
)],
259 thumb_mode(regs
) ? " (T)" : "",
260 get_fs() == get_ds() ? "kernel" : "user");
265 " mrc p15, 0, %0, c1, c0\n"
267 printk("Control: %04X\n", ctrl
);
269 #ifdef CONFIG_CPU_CP15_MMU
271 unsigned int transbase
, dac
;
273 " mrc p15, 0, %0, c2, c0\n"
274 " mrc p15, 0, %1, c3, c0\n"
275 : "=r" (transbase
), "=r" (dac
));
276 printk("Table: %08X DAC: %08X\n",
283 void show_regs(struct pt_regs
* regs
)
286 printk("Pid: %d, comm: %20s\n", current
->pid
, current
->comm
);
291 void show_fpregs(struct user_fp
*regs
)
295 for (i
= 0; i
< 8; i
++) {
299 p
= (unsigned long *)(regs
->fpregs
+ i
);
301 switch (regs
->ftype
[i
]) {
302 case 1: type
= 'f'; break;
303 case 2: type
= 'd'; break;
304 case 3: type
= 'e'; break;
305 default: type
= '?'; break;
310 printk(" f%d(%c): %08lx %08lx %08lx%c",
311 i
, type
, p
[0], p
[1], p
[2], i
& 1 ? '\n' : ' ');
315 printk("FPSR: %08lx FPCR: %08lx\n",
316 (unsigned long)regs
->fpsr
,
317 (unsigned long)regs
->fpcr
);
321 * Task structure and kernel stack allocation.
323 struct thread_info_list
{
328 static DEFINE_PER_CPU(struct thread_info_list
, thread_info_list
) = { NULL
, 0 };
330 #define EXTRA_TASK_STRUCT 4
332 struct thread_info
*alloc_thread_info(struct task_struct
*task
)
334 struct thread_info
*thread
= NULL
;
336 if (EXTRA_TASK_STRUCT
) {
337 struct thread_info_list
*th
= &get_cpu_var(thread_info_list
);
338 unsigned long *p
= th
->head
;
341 th
->head
= (unsigned long *)p
[0];
344 put_cpu_var(thread_info_list
);
346 thread
= (struct thread_info
*)p
;
350 thread
= (struct thread_info
*)
351 __get_free_pages(GFP_KERNEL
, THREAD_SIZE_ORDER
);
353 #ifdef CONFIG_DEBUG_STACK_USAGE
355 * The stack must be cleared if you want SYSRQ-T to
356 * give sensible stack usage information
359 memzero(thread
, THREAD_SIZE
);
364 void free_thread_info(struct thread_info
*thread
)
366 if (EXTRA_TASK_STRUCT
) {
367 struct thread_info_list
*th
= &get_cpu_var(thread_info_list
);
368 if (th
->nr
< EXTRA_TASK_STRUCT
) {
369 unsigned long *p
= (unsigned long *)thread
;
370 p
[0] = (unsigned long)th
->head
;
373 put_cpu_var(thread_info_list
);
376 put_cpu_var(thread_info_list
);
378 free_pages((unsigned long)thread
, THREAD_SIZE_ORDER
);
382 * Free current thread data structures etc..
384 void exit_thread(void)
388 ATOMIC_NOTIFIER_HEAD(thread_notify_head
);
390 EXPORT_SYMBOL_GPL(thread_notify_head
);
392 void flush_thread(void)
394 struct thread_info
*thread
= current_thread_info();
395 struct task_struct
*tsk
= current
;
397 memset(thread
->used_cp
, 0, sizeof(thread
->used_cp
));
398 memset(&tsk
->thread
.debug
, 0, sizeof(struct debug_info
));
399 memset(&thread
->fpstate
, 0, sizeof(union fp_state
));
401 thread_notify(THREAD_NOTIFY_FLUSH
, thread
);
404 void release_thread(struct task_struct
*dead_task
)
406 struct thread_info
*thread
= task_thread_info(dead_task
);
408 thread_notify(THREAD_NOTIFY_RELEASE
, thread
);
411 asmlinkage
void ret_from_fork(void) __asm__("ret_from_fork");
414 copy_thread(int nr
, unsigned long clone_flags
, unsigned long stack_start
,
415 unsigned long stk_sz
, struct task_struct
*p
, struct pt_regs
*regs
)
417 struct thread_info
*thread
= task_thread_info(p
);
418 struct pt_regs
*childregs
= task_pt_regs(p
);
421 childregs
->ARM_r0
= 0;
422 childregs
->ARM_sp
= stack_start
;
424 memset(&thread
->cpu_context
, 0, sizeof(struct cpu_context_save
));
425 thread
->cpu_context
.sp
= (unsigned long)childregs
;
426 thread
->cpu_context
.pc
= (unsigned long)ret_from_fork
;
428 if (clone_flags
& CLONE_SETTLS
)
429 thread
->tp_value
= regs
->ARM_r3
;
435 * fill in the fpe structure for a core dump...
437 int dump_fpu (struct pt_regs
*regs
, struct user_fp
*fp
)
439 struct thread_info
*thread
= current_thread_info();
440 int used_math
= thread
->used_cp
[1] | thread
->used_cp
[2];
443 memcpy(fp
, &thread
->fpstate
.soft
, sizeof (*fp
));
445 return used_math
!= 0;
447 EXPORT_SYMBOL(dump_fpu
);
450 * fill in the user structure for a core dump..
452 void dump_thread(struct pt_regs
* regs
, struct user
* dump
)
454 struct task_struct
*tsk
= current
;
456 dump
->magic
= CMAGIC
;
457 dump
->start_code
= tsk
->mm
->start_code
;
458 dump
->start_stack
= regs
->ARM_sp
& ~(PAGE_SIZE
- 1);
460 dump
->u_tsize
= (tsk
->mm
->end_code
- tsk
->mm
->start_code
) >> PAGE_SHIFT
;
461 dump
->u_dsize
= (tsk
->mm
->brk
- tsk
->mm
->start_data
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
464 dump
->u_debugreg
[0] = tsk
->thread
.debug
.bp
[0].address
;
465 dump
->u_debugreg
[1] = tsk
->thread
.debug
.bp
[1].address
;
466 dump
->u_debugreg
[2] = tsk
->thread
.debug
.bp
[0].insn
.arm
;
467 dump
->u_debugreg
[3] = tsk
->thread
.debug
.bp
[1].insn
.arm
;
468 dump
->u_debugreg
[4] = tsk
->thread
.debug
.nsaved
;
470 if (dump
->start_stack
< 0x04000000)
471 dump
->u_ssize
= (0x04000000 - dump
->start_stack
) >> PAGE_SHIFT
;
474 dump
->u_fpvalid
= dump_fpu (regs
, &dump
->u_fp
);
476 EXPORT_SYMBOL(dump_thread
);
479 * Shuffle the argument into the correct register before calling the
480 * thread function. r1 is the thread argument, r2 is the pointer to
481 * the thread function, and r3 points to the exit function.
483 extern void kernel_thread_helper(void);
484 asm( ".section .text\n"
486 " .type kernel_thread_helper, #function\n"
487 "kernel_thread_helper:\n"
491 " .size kernel_thread_helper, . - kernel_thread_helper\n"
495 * Create a kernel thread.
497 pid_t
kernel_thread(int (*fn
)(void *), void *arg
, unsigned long flags
)
501 memset(®s
, 0, sizeof(regs
));
503 regs
.ARM_r1
= (unsigned long)arg
;
504 regs
.ARM_r2
= (unsigned long)fn
;
505 regs
.ARM_r3
= (unsigned long)do_exit
;
506 regs
.ARM_pc
= (unsigned long)kernel_thread_helper
;
507 regs
.ARM_cpsr
= SVC_MODE
;
509 return do_fork(flags
|CLONE_VM
|CLONE_UNTRACED
, 0, ®s
, 0, NULL
, NULL
);
511 EXPORT_SYMBOL(kernel_thread
);
513 unsigned long get_wchan(struct task_struct
*p
)
515 unsigned long fp
, lr
;
516 unsigned long stack_start
, stack_end
;
518 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
521 stack_start
= (unsigned long)end_of_stack(p
);
522 stack_end
= (unsigned long)task_stack_page(p
) + THREAD_SIZE
;
524 fp
= thread_saved_fp(p
);
526 if (fp
< stack_start
|| fp
> stack_end
)
528 lr
= pc_pointer (((unsigned long *)fp
)[-1]);
529 if (!in_sched_functions(lr
))
531 fp
= *(unsigned long *) (fp
- 12);
532 } while (count
++ < 16);