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/config.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.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 #include <linux/cpu.h>
32 #include <asm/processor.h>
33 #include <asm/system.h>
34 #include <asm/uaccess.h>
35 #include <asm/mach/time.h>
37 extern const char *processor_modes
[];
38 extern void setup_mm_for_reboot(char mode
);
40 static volatile int hlt_counter
;
42 #include <asm/arch/system.h>
44 void disable_hlt(void)
49 EXPORT_SYMBOL(disable_hlt
);
56 EXPORT_SYMBOL(enable_hlt
);
58 static int __init
nohlt_setup(char *__unused
)
64 static int __init
hlt_setup(char *__unused
)
70 __setup("nohlt", nohlt_setup
);
71 __setup("hlt", hlt_setup
);
74 * The following aren't currently used.
76 void (*pm_idle
)(void);
77 EXPORT_SYMBOL(pm_idle
);
79 void (*pm_power_off
)(void);
80 EXPORT_SYMBOL(pm_power_off
);
83 * This is our default idle handler. We need to disable
84 * interrupts here to ensure we don't miss a wakeup call.
86 void default_idle(void)
92 if (!need_resched()) {
93 timer_dyn_reprogram();
101 * The idle thread. We try to conserve power, while trying to keep
102 * overall latency low. The architecture specific idle is passed
103 * a value to indicate the level of "idleness" of the system.
109 /* endless idle loop with no priority at all */
111 void (*idle
)(void) = pm_idle
;
113 #ifdef CONFIG_HOTPLUG_CPU
114 if (cpu_is_offline(smp_processor_id())) {
115 leds_event(led_idle_start
);
122 leds_event(led_idle_start
);
123 while (!need_resched())
125 leds_event(led_idle_end
);
126 preempt_enable_no_resched();
132 static char reboot_mode
= 'h';
134 int __init
reboot_setup(char *str
)
136 reboot_mode
= str
[0];
140 __setup("reboot=", reboot_setup
);
142 void machine_halt(void)
147 void machine_power_off(void)
154 void machine_restart(char * __unused
)
157 * Clean and disable cache, and turn off interrupts
162 * Tell the mm system that we are going to reboot -
163 * we may need it to insert some 1:1 mappings so that
166 setup_mm_for_reboot(reboot_mode
);
169 * Now call the architecture specific reboot code.
171 arch_reset(reboot_mode
);
174 * Whoops - the architecture was unable to reboot.
178 printk("Reboot failed -- System halted\n");
182 void __show_regs(struct pt_regs
*regs
)
184 unsigned long flags
= condition_codes(regs
);
186 printk("CPU: %d\n", smp_processor_id());
187 print_symbol("PC is at %s\n", instruction_pointer(regs
));
188 print_symbol("LR is at %s\n", regs
->ARM_lr
);
189 printk("pc : [<%08lx>] lr : [<%08lx>] %s\n"
190 "sp : %08lx ip : %08lx fp : %08lx\n",
191 instruction_pointer(regs
),
192 regs
->ARM_lr
, print_tainted(), regs
->ARM_sp
,
193 regs
->ARM_ip
, regs
->ARM_fp
);
194 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
195 regs
->ARM_r10
, regs
->ARM_r9
,
197 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
198 regs
->ARM_r7
, regs
->ARM_r6
,
199 regs
->ARM_r5
, regs
->ARM_r4
);
200 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
201 regs
->ARM_r3
, regs
->ARM_r2
,
202 regs
->ARM_r1
, regs
->ARM_r0
);
203 printk("Flags: %c%c%c%c",
204 flags
& PSR_N_BIT
? 'N' : 'n',
205 flags
& PSR_Z_BIT
? 'Z' : 'z',
206 flags
& PSR_C_BIT
? 'C' : 'c',
207 flags
& PSR_V_BIT
? 'V' : 'v');
208 printk(" IRQs o%s FIQs o%s Mode %s%s Segment %s\n",
209 interrupts_enabled(regs
) ? "n" : "ff",
210 fast_interrupts_enabled(regs
) ? "n" : "ff",
211 processor_modes
[processor_mode(regs
)],
212 thumb_mode(regs
) ? " (T)" : "",
213 get_fs() == get_ds() ? "kernel" : "user");
215 unsigned int ctrl
, transbase
, dac
;
217 " mrc p15, 0, %0, c1, c0\n"
218 " mrc p15, 0, %1, c2, c0\n"
219 " mrc p15, 0, %2, c3, c0\n"
220 : "=r" (ctrl
), "=r" (transbase
), "=r" (dac
));
221 printk("Control: %04X Table: %08X DAC: %08X\n",
222 ctrl
, transbase
, dac
);
226 void show_regs(struct pt_regs
* regs
)
229 printk("Pid: %d, comm: %20s\n", current
->pid
, current
->comm
);
234 void show_fpregs(struct user_fp
*regs
)
238 for (i
= 0; i
< 8; i
++) {
242 p
= (unsigned long *)(regs
->fpregs
+ i
);
244 switch (regs
->ftype
[i
]) {
245 case 1: type
= 'f'; break;
246 case 2: type
= 'd'; break;
247 case 3: type
= 'e'; break;
248 default: type
= '?'; break;
253 printk(" f%d(%c): %08lx %08lx %08lx%c",
254 i
, type
, p
[0], p
[1], p
[2], i
& 1 ? '\n' : ' ');
258 printk("FPSR: %08lx FPCR: %08lx\n",
259 (unsigned long)regs
->fpsr
,
260 (unsigned long)regs
->fpcr
);
264 * Task structure and kernel stack allocation.
266 static unsigned long *thread_info_head
;
267 static unsigned int nr_thread_info
;
269 #define EXTRA_TASK_STRUCT 4
271 struct thread_info
*alloc_thread_info(struct task_struct
*task
)
273 struct thread_info
*thread
= NULL
;
275 if (EXTRA_TASK_STRUCT
) {
276 unsigned long *p
= thread_info_head
;
279 thread_info_head
= (unsigned long *)p
[0];
282 thread
= (struct thread_info
*)p
;
286 thread
= (struct thread_info
*)
287 __get_free_pages(GFP_KERNEL
, THREAD_SIZE_ORDER
);
289 #ifdef CONFIG_DEBUG_STACK_USAGE
291 * The stack must be cleared if you want SYSRQ-T to
292 * give sensible stack usage information
295 memzero(thread
, THREAD_SIZE
);
300 void free_thread_info(struct thread_info
*thread
)
302 if (EXTRA_TASK_STRUCT
&& nr_thread_info
< EXTRA_TASK_STRUCT
) {
303 unsigned long *p
= (unsigned long *)thread
;
304 p
[0] = (unsigned long)thread_info_head
;
305 thread_info_head
= p
;
308 free_pages((unsigned long)thread
, THREAD_SIZE_ORDER
);
312 * Free current thread data structures etc..
314 void exit_thread(void)
318 static void default_fp_init(union fp_state
*fp
)
320 memset(fp
, 0, sizeof(union fp_state
));
323 void (*fp_init
)(union fp_state
*) = default_fp_init
;
324 EXPORT_SYMBOL(fp_init
);
326 void flush_thread(void)
328 struct thread_info
*thread
= current_thread_info();
329 struct task_struct
*tsk
= current
;
331 memset(thread
->used_cp
, 0, sizeof(thread
->used_cp
));
332 memset(&tsk
->thread
.debug
, 0, sizeof(struct debug_info
));
333 #if defined(CONFIG_IWMMXT)
334 iwmmxt_task_release(thread
);
336 fp_init(&thread
->fpstate
);
337 #if defined(CONFIG_VFP)
338 vfp_flush_thread(&thread
->vfpstate
);
342 void release_thread(struct task_struct
*dead_task
)
344 #if defined(CONFIG_VFP)
345 vfp_release_thread(&task_thread_info(dead_task
)->vfpstate
);
347 #if defined(CONFIG_IWMMXT)
348 iwmmxt_task_release(task_thread_info(dead_task
));
352 asmlinkage
void ret_from_fork(void) __asm__("ret_from_fork");
355 copy_thread(int nr
, unsigned long clone_flags
, unsigned long stack_start
,
356 unsigned long stk_sz
, struct task_struct
*p
, struct pt_regs
*regs
)
358 struct thread_info
*thread
= task_thread_info(p
);
359 struct pt_regs
*childregs
= task_pt_regs(p
);
362 childregs
->ARM_r0
= 0;
363 childregs
->ARM_sp
= stack_start
;
365 memset(&thread
->cpu_context
, 0, sizeof(struct cpu_context_save
));
366 thread
->cpu_context
.sp
= (unsigned long)childregs
;
367 thread
->cpu_context
.pc
= (unsigned long)ret_from_fork
;
369 if (clone_flags
& CLONE_SETTLS
)
370 thread
->tp_value
= regs
->ARM_r3
;
376 * fill in the fpe structure for a core dump...
378 int dump_fpu (struct pt_regs
*regs
, struct user_fp
*fp
)
380 struct thread_info
*thread
= current_thread_info();
381 int used_math
= thread
->used_cp
[1] | thread
->used_cp
[2];
384 memcpy(fp
, &thread
->fpstate
.soft
, sizeof (*fp
));
386 return used_math
!= 0;
388 EXPORT_SYMBOL(dump_fpu
);
391 * fill in the user structure for a core dump..
393 void dump_thread(struct pt_regs
* regs
, struct user
* dump
)
395 struct task_struct
*tsk
= current
;
397 dump
->magic
= CMAGIC
;
398 dump
->start_code
= tsk
->mm
->start_code
;
399 dump
->start_stack
= regs
->ARM_sp
& ~(PAGE_SIZE
- 1);
401 dump
->u_tsize
= (tsk
->mm
->end_code
- tsk
->mm
->start_code
) >> PAGE_SHIFT
;
402 dump
->u_dsize
= (tsk
->mm
->brk
- tsk
->mm
->start_data
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
405 dump
->u_debugreg
[0] = tsk
->thread
.debug
.bp
[0].address
;
406 dump
->u_debugreg
[1] = tsk
->thread
.debug
.bp
[1].address
;
407 dump
->u_debugreg
[2] = tsk
->thread
.debug
.bp
[0].insn
.arm
;
408 dump
->u_debugreg
[3] = tsk
->thread
.debug
.bp
[1].insn
.arm
;
409 dump
->u_debugreg
[4] = tsk
->thread
.debug
.nsaved
;
411 if (dump
->start_stack
< 0x04000000)
412 dump
->u_ssize
= (0x04000000 - dump
->start_stack
) >> PAGE_SHIFT
;
415 dump
->u_fpvalid
= dump_fpu (regs
, &dump
->u_fp
);
417 EXPORT_SYMBOL(dump_thread
);
420 * Shuffle the argument into the correct register before calling the
421 * thread function. r1 is the thread argument, r2 is the pointer to
422 * the thread function, and r3 points to the exit function.
424 extern void kernel_thread_helper(void);
425 asm( ".section .text\n"
427 " .type kernel_thread_helper, #function\n"
428 "kernel_thread_helper:\n"
432 " .size kernel_thread_helper, . - kernel_thread_helper\n"
436 * Create a kernel thread.
438 pid_t
kernel_thread(int (*fn
)(void *), void *arg
, unsigned long flags
)
442 memset(®s
, 0, sizeof(regs
));
444 regs
.ARM_r1
= (unsigned long)arg
;
445 regs
.ARM_r2
= (unsigned long)fn
;
446 regs
.ARM_r3
= (unsigned long)do_exit
;
447 regs
.ARM_pc
= (unsigned long)kernel_thread_helper
;
448 regs
.ARM_cpsr
= SVC_MODE
;
450 return do_fork(flags
|CLONE_VM
|CLONE_UNTRACED
, 0, ®s
, 0, NULL
, NULL
);
452 EXPORT_SYMBOL(kernel_thread
);
454 unsigned long get_wchan(struct task_struct
*p
)
456 unsigned long fp
, lr
;
457 unsigned long stack_start
, stack_end
;
459 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
462 stack_start
= (unsigned long)end_of_stack(p
);
463 stack_end
= (unsigned long)task_stack_page(p
) + THREAD_SIZE
;
465 fp
= thread_saved_fp(p
);
467 if (fp
< stack_start
|| fp
> stack_end
)
469 lr
= pc_pointer (((unsigned long *)fp
)[-1]);
470 if (!in_sched_functions(lr
))
472 fp
= *(unsigned long *) (fp
- 12);
473 } while (count
++ < 16);
476 EXPORT_SYMBOL(get_wchan
);