]>
git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - arch/arm/kernel/process.c
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/slab.h>
20 #include <linux/user.h>
21 #include <linux/delay.h>
22 #include <linux/reboot.h>
23 #include <linux/interrupt.h>
24 #include <linux/kallsyms.h>
25 #include <linux/init.h>
26 #include <linux/cpu.h>
27 #include <linux/elfcore.h>
29 #include <linux/tick.h>
30 #include <linux/utsname.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 static const char *processor_modes
[] = {
40 "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
41 "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
42 "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
43 "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
46 static const char *isa_modes
[] = {
47 "ARM" , "Thumb" , "Jazelle", "ThumbEE"
50 extern void setup_mm_for_reboot(char mode
);
52 static volatile int hlt_counter
;
54 #include <mach/system.h>
56 void disable_hlt(void)
61 EXPORT_SYMBOL(disable_hlt
);
68 EXPORT_SYMBOL(enable_hlt
);
70 static int __init
nohlt_setup(char *__unused
)
76 static int __init
hlt_setup(char *__unused
)
82 __setup("nohlt", nohlt_setup
);
83 __setup("hlt", hlt_setup
);
85 void arm_machine_restart(char mode
)
88 * Clean and disable cache, and turn off interrupts
93 * Tell the mm system that we are going to reboot -
94 * we may need it to insert some 1:1 mappings so that
97 setup_mm_for_reboot(mode
);
100 * Now call the architecture specific reboot code.
105 * Whoops - the architecture was unable to reboot.
109 printk("Reboot failed -- System halted\n");
114 * Function pointers to optional machine specific functions
116 void (*pm_idle
)(void);
117 EXPORT_SYMBOL(pm_idle
);
119 void (*pm_power_off
)(void);
120 EXPORT_SYMBOL(pm_power_off
);
122 void (*arm_pm_restart
)(char str
) = arm_machine_restart
;
123 EXPORT_SYMBOL_GPL(arm_pm_restart
);
127 * This is our default idle handler. We need to disable
128 * interrupts here to ensure we don't miss a wakeup call.
130 static void default_idle(void)
143 * The idle thread. We try to conserve power, while trying to keep
144 * overall latency low. The architecture specific idle is passed
145 * a value to indicate the level of "idleness" of the system.
151 /* endless idle loop with no priority at all */
153 void (*idle
)(void) = pm_idle
;
155 #ifdef CONFIG_HOTPLUG_CPU
156 if (cpu_is_offline(smp_processor_id())) {
157 leds_event(led_idle_start
);
164 leds_event(led_idle_start
);
165 tick_nohz_stop_sched_tick(1);
166 while (!need_resched())
168 leds_event(led_idle_end
);
169 tick_nohz_restart_sched_tick();
170 preempt_enable_no_resched();
176 static char reboot_mode
= 'h';
178 int __init
reboot_setup(char *str
)
180 reboot_mode
= str
[0];
184 __setup("reboot=", reboot_setup
);
186 void machine_halt(void)
191 void machine_power_off(void)
197 void machine_restart(char * __unused
)
199 arm_pm_restart(reboot_mode
);
202 void __show_regs(struct pt_regs
*regs
)
207 printk("CPU: %d %s (%s %.*s)\n",
208 smp_processor_id(), print_tainted(), init_utsname()->release
,
209 (int)strcspn(init_utsname()->version
, " "),
210 init_utsname()->version
);
211 print_symbol("PC is at %s\n", instruction_pointer(regs
));
212 print_symbol("LR is at %s\n", regs
->ARM_lr
);
213 printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
214 "sp : %08lx ip : %08lx fp : %08lx\n",
215 regs
->ARM_pc
, regs
->ARM_lr
, regs
->ARM_cpsr
,
216 regs
->ARM_sp
, regs
->ARM_ip
, regs
->ARM_fp
);
217 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
218 regs
->ARM_r10
, regs
->ARM_r9
,
220 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
221 regs
->ARM_r7
, regs
->ARM_r6
,
222 regs
->ARM_r5
, regs
->ARM_r4
);
223 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
224 regs
->ARM_r3
, regs
->ARM_r2
,
225 regs
->ARM_r1
, regs
->ARM_r0
);
227 flags
= regs
->ARM_cpsr
;
228 buf
[0] = flags
& PSR_N_BIT
? 'N' : 'n';
229 buf
[1] = flags
& PSR_Z_BIT
? 'Z' : 'z';
230 buf
[2] = flags
& PSR_C_BIT
? 'C' : 'c';
231 buf
[3] = flags
& PSR_V_BIT
? 'V' : 'v';
234 printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
235 buf
, interrupts_enabled(regs
) ? "n" : "ff",
236 fast_interrupts_enabled(regs
) ? "n" : "ff",
237 processor_modes
[processor_mode(regs
)],
238 isa_modes
[isa_mode(regs
)],
239 get_fs() == get_ds() ? "kernel" : "user");
240 #ifdef CONFIG_CPU_CP15
245 #ifdef CONFIG_CPU_CP15_MMU
247 unsigned int transbase
, dac
;
248 asm("mrc p15, 0, %0, c2, c0\n\t"
249 "mrc p15, 0, %1, c3, c0\n"
250 : "=r" (transbase
), "=r" (dac
));
251 snprintf(buf
, sizeof(buf
), " Table: %08x DAC: %08x",
255 asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl
));
257 printk("Control: %08x%s\n", ctrl
, buf
);
262 void show_regs(struct pt_regs
* regs
)
265 printk("Pid: %d, comm: %20s\n", task_pid_nr(current
), current
->comm
);
270 void show_fpregs(struct user_fp
*regs
)
274 for (i
= 0; i
< 8; i
++) {
278 p
= (unsigned long *)(regs
->fpregs
+ i
);
280 switch (regs
->ftype
[i
]) {
281 case 1: type
= 'f'; break;
282 case 2: type
= 'd'; break;
283 case 3: type
= 'e'; break;
284 default: type
= '?'; break;
289 printk(" f%d(%c): %08lx %08lx %08lx%c",
290 i
, type
, p
[0], p
[1], p
[2], i
& 1 ? '\n' : ' ');
294 printk("FPSR: %08lx FPCR: %08lx\n",
295 (unsigned long)regs
->fpsr
,
296 (unsigned long)regs
->fpcr
);
300 * Free current thread data structures etc..
302 void exit_thread(void)
306 ATOMIC_NOTIFIER_HEAD(thread_notify_head
);
308 EXPORT_SYMBOL_GPL(thread_notify_head
);
310 void flush_thread(void)
312 struct thread_info
*thread
= current_thread_info();
313 struct task_struct
*tsk
= current
;
315 memset(thread
->used_cp
, 0, sizeof(thread
->used_cp
));
316 memset(&tsk
->thread
.debug
, 0, sizeof(struct debug_info
));
317 memset(&thread
->fpstate
, 0, sizeof(union fp_state
));
319 thread_notify(THREAD_NOTIFY_FLUSH
, thread
);
322 void release_thread(struct task_struct
*dead_task
)
324 struct thread_info
*thread
= task_thread_info(dead_task
);
326 thread_notify(THREAD_NOTIFY_RELEASE
, thread
);
329 asmlinkage
void ret_from_fork(void) __asm__("ret_from_fork");
332 copy_thread(int nr
, unsigned long clone_flags
, unsigned long stack_start
,
333 unsigned long stk_sz
, struct task_struct
*p
, struct pt_regs
*regs
)
335 struct thread_info
*thread
= task_thread_info(p
);
336 struct pt_regs
*childregs
= task_pt_regs(p
);
339 childregs
->ARM_r0
= 0;
340 childregs
->ARM_sp
= stack_start
;
342 memset(&thread
->cpu_context
, 0, sizeof(struct cpu_context_save
));
343 thread
->cpu_context
.sp
= (unsigned long)childregs
;
344 thread
->cpu_context
.pc
= (unsigned long)ret_from_fork
;
346 if (clone_flags
& CLONE_SETTLS
)
347 thread
->tp_value
= regs
->ARM_r3
;
353 * fill in the fpe structure for a core dump...
355 int dump_fpu (struct pt_regs
*regs
, struct user_fp
*fp
)
357 struct thread_info
*thread
= current_thread_info();
358 int used_math
= thread
->used_cp
[1] | thread
->used_cp
[2];
361 memcpy(fp
, &thread
->fpstate
.soft
, sizeof (*fp
));
363 return used_math
!= 0;
365 EXPORT_SYMBOL(dump_fpu
);
368 * Shuffle the argument into the correct register before calling the
369 * thread function. r1 is the thread argument, r2 is the pointer to
370 * the thread function, and r3 points to the exit function.
372 extern void kernel_thread_helper(void);
373 asm( ".section .text\n"
375 " .type kernel_thread_helper, #function\n"
376 "kernel_thread_helper:\n"
380 " .size kernel_thread_helper, . - kernel_thread_helper\n"
384 * Create a kernel thread.
386 pid_t
kernel_thread(int (*fn
)(void *), void *arg
, unsigned long flags
)
390 memset(®s
, 0, sizeof(regs
));
392 regs
.ARM_r1
= (unsigned long)arg
;
393 regs
.ARM_r2
= (unsigned long)fn
;
394 regs
.ARM_r3
= (unsigned long)do_exit
;
395 regs
.ARM_pc
= (unsigned long)kernel_thread_helper
;
396 regs
.ARM_cpsr
= SVC_MODE
;
398 return do_fork(flags
|CLONE_VM
|CLONE_UNTRACED
, 0, ®s
, 0, NULL
, NULL
);
400 EXPORT_SYMBOL(kernel_thread
);
402 unsigned long get_wchan(struct task_struct
*p
)
404 unsigned long fp
, lr
;
405 unsigned long stack_start
, stack_end
;
407 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
410 stack_start
= (unsigned long)end_of_stack(p
);
411 stack_end
= (unsigned long)task_stack_page(p
) + THREAD_SIZE
;
413 fp
= thread_saved_fp(p
);
415 if (fp
< stack_start
|| fp
> stack_end
)
417 lr
= pc_pointer (((unsigned long *)fp
)[-1]);
418 if (!in_sched_functions(lr
))
420 fp
= *(unsigned long *) (fp
- 12);
421 } while (count
++ < 16);