]>
git.proxmox.com Git - mirror_ubuntu-jammy-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/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>
30 #include <asm/system.h>
33 #include <asm/processor.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)
89 if (!need_resched() && !hlt_counter
) {
90 timer_dyn_reprogram();
97 * The idle thread. We try to conserve power, while trying to keep
98 * overall latency low. The architecture specific idle is passed
99 * a value to indicate the level of "idleness" of the system.
105 /* endless idle loop with no priority at all */
107 void (*idle
)(void) = pm_idle
;
111 leds_event(led_idle_start
);
112 while (!need_resched())
114 leds_event(led_idle_end
);
120 static char reboot_mode
= 'h';
122 int __init
reboot_setup(char *str
)
124 reboot_mode
= str
[0];
128 __setup("reboot=", reboot_setup
);
130 void machine_halt(void)
135 void machine_power_off(void)
142 void machine_restart(char * __unused
)
145 * Clean and disable cache, and turn off interrupts
150 * Tell the mm system that we are going to reboot -
151 * we may need it to insert some 1:1 mappings so that
154 setup_mm_for_reboot(reboot_mode
);
157 * Now call the architecture specific reboot code.
159 arch_reset(reboot_mode
);
162 * Whoops - the architecture was unable to reboot.
166 printk("Reboot failed -- System halted\n");
170 void __show_regs(struct pt_regs
*regs
)
172 unsigned long flags
= condition_codes(regs
);
174 printk("CPU: %d\n", smp_processor_id());
175 print_symbol("PC is at %s\n", instruction_pointer(regs
));
176 print_symbol("LR is at %s\n", regs
->ARM_lr
);
177 printk("pc : [<%08lx>] lr : [<%08lx>] %s\n"
178 "sp : %08lx ip : %08lx fp : %08lx\n",
179 instruction_pointer(regs
),
180 regs
->ARM_lr
, print_tainted(), regs
->ARM_sp
,
181 regs
->ARM_ip
, regs
->ARM_fp
);
182 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
183 regs
->ARM_r10
, regs
->ARM_r9
,
185 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
186 regs
->ARM_r7
, regs
->ARM_r6
,
187 regs
->ARM_r5
, regs
->ARM_r4
);
188 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
189 regs
->ARM_r3
, regs
->ARM_r2
,
190 regs
->ARM_r1
, regs
->ARM_r0
);
191 printk("Flags: %c%c%c%c",
192 flags
& PSR_N_BIT
? 'N' : 'n',
193 flags
& PSR_Z_BIT
? 'Z' : 'z',
194 flags
& PSR_C_BIT
? 'C' : 'c',
195 flags
& PSR_V_BIT
? 'V' : 'v');
196 printk(" IRQs o%s FIQs o%s Mode %s%s Segment %s\n",
197 interrupts_enabled(regs
) ? "n" : "ff",
198 fast_interrupts_enabled(regs
) ? "n" : "ff",
199 processor_modes
[processor_mode(regs
)],
200 thumb_mode(regs
) ? " (T)" : "",
201 get_fs() == get_ds() ? "kernel" : "user");
203 unsigned int ctrl
, transbase
, dac
;
205 " mrc p15, 0, %0, c1, c0\n"
206 " mrc p15, 0, %1, c2, c0\n"
207 " mrc p15, 0, %2, c3, c0\n"
208 : "=r" (ctrl
), "=r" (transbase
), "=r" (dac
));
209 printk("Control: %04X Table: %08X DAC: %08X\n",
210 ctrl
, transbase
, dac
);
214 void show_regs(struct pt_regs
* regs
)
217 printk("Pid: %d, comm: %20s\n", current
->pid
, current
->comm
);
222 void show_fpregs(struct user_fp
*regs
)
226 for (i
= 0; i
< 8; i
++) {
230 p
= (unsigned long *)(regs
->fpregs
+ i
);
232 switch (regs
->ftype
[i
]) {
233 case 1: type
= 'f'; break;
234 case 2: type
= 'd'; break;
235 case 3: type
= 'e'; break;
236 default: type
= '?'; break;
241 printk(" f%d(%c): %08lx %08lx %08lx%c",
242 i
, type
, p
[0], p
[1], p
[2], i
& 1 ? '\n' : ' ');
246 printk("FPSR: %08lx FPCR: %08lx\n",
247 (unsigned long)regs
->fpsr
,
248 (unsigned long)regs
->fpcr
);
252 * Task structure and kernel stack allocation.
254 static unsigned long *thread_info_head
;
255 static unsigned int nr_thread_info
;
257 #define EXTRA_TASK_STRUCT 4
259 struct thread_info
*alloc_thread_info(struct task_struct
*task
)
261 struct thread_info
*thread
= NULL
;
263 if (EXTRA_TASK_STRUCT
) {
264 unsigned long *p
= thread_info_head
;
267 thread_info_head
= (unsigned long *)p
[0];
270 thread
= (struct thread_info
*)p
;
274 thread
= (struct thread_info
*)
275 __get_free_pages(GFP_KERNEL
, THREAD_SIZE_ORDER
);
277 #ifdef CONFIG_DEBUG_STACK_USAGE
279 * The stack must be cleared if you want SYSRQ-T to
280 * give sensible stack usage information
283 memzero(thread
, THREAD_SIZE
);
288 void free_thread_info(struct thread_info
*thread
)
290 if (EXTRA_TASK_STRUCT
&& nr_thread_info
< EXTRA_TASK_STRUCT
) {
291 unsigned long *p
= (unsigned long *)thread
;
292 p
[0] = (unsigned long)thread_info_head
;
293 thread_info_head
= p
;
296 free_pages((unsigned long)thread
, THREAD_SIZE_ORDER
);
300 * Free current thread data structures etc..
302 void exit_thread(void)
306 static void default_fp_init(union fp_state
*fp
)
308 memset(fp
, 0, sizeof(union fp_state
));
311 void (*fp_init
)(union fp_state
*) = default_fp_init
;
312 EXPORT_SYMBOL(fp_init
);
314 void flush_thread(void)
316 struct thread_info
*thread
= current_thread_info();
317 struct task_struct
*tsk
= current
;
319 memset(thread
->used_cp
, 0, sizeof(thread
->used_cp
));
320 memset(&tsk
->thread
.debug
, 0, sizeof(struct debug_info
));
321 #if defined(CONFIG_IWMMXT)
322 iwmmxt_task_release(thread
);
324 fp_init(&thread
->fpstate
);
325 #if defined(CONFIG_VFP)
326 vfp_flush_thread(&thread
->vfpstate
);
330 void release_thread(struct task_struct
*dead_task
)
332 #if defined(CONFIG_VFP)
333 vfp_release_thread(&dead_task
->thread_info
->vfpstate
);
335 #if defined(CONFIG_IWMMXT)
336 iwmmxt_task_release(dead_task
->thread_info
);
340 asmlinkage
void ret_from_fork(void) __asm__("ret_from_fork");
343 copy_thread(int nr
, unsigned long clone_flags
, unsigned long stack_start
,
344 unsigned long stk_sz
, struct task_struct
*p
, struct pt_regs
*regs
)
346 struct thread_info
*thread
= p
->thread_info
;
347 struct pt_regs
*childregs
;
349 childregs
= ((struct pt_regs
*)((unsigned long)thread
+ THREAD_START_SP
)) - 1;
351 childregs
->ARM_r0
= 0;
352 childregs
->ARM_sp
= stack_start
;
354 memset(&thread
->cpu_context
, 0, sizeof(struct cpu_context_save
));
355 thread
->cpu_context
.sp
= (unsigned long)childregs
;
356 thread
->cpu_context
.pc
= (unsigned long)ret_from_fork
;
358 if (clone_flags
& CLONE_SETTLS
)
359 thread
->tp_value
= regs
->ARM_r3
;
365 * fill in the fpe structure for a core dump...
367 int dump_fpu (struct pt_regs
*regs
, struct user_fp
*fp
)
369 struct thread_info
*thread
= current_thread_info();
370 int used_math
= thread
->used_cp
[1] | thread
->used_cp
[2];
373 memcpy(fp
, &thread
->fpstate
.soft
, sizeof (*fp
));
375 return used_math
!= 0;
377 EXPORT_SYMBOL(dump_fpu
);
380 * fill in the user structure for a core dump..
382 void dump_thread(struct pt_regs
* regs
, struct user
* dump
)
384 struct task_struct
*tsk
= current
;
386 dump
->magic
= CMAGIC
;
387 dump
->start_code
= tsk
->mm
->start_code
;
388 dump
->start_stack
= regs
->ARM_sp
& ~(PAGE_SIZE
- 1);
390 dump
->u_tsize
= (tsk
->mm
->end_code
- tsk
->mm
->start_code
) >> PAGE_SHIFT
;
391 dump
->u_dsize
= (tsk
->mm
->brk
- tsk
->mm
->start_data
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
394 dump
->u_debugreg
[0] = tsk
->thread
.debug
.bp
[0].address
;
395 dump
->u_debugreg
[1] = tsk
->thread
.debug
.bp
[1].address
;
396 dump
->u_debugreg
[2] = tsk
->thread
.debug
.bp
[0].insn
.arm
;
397 dump
->u_debugreg
[3] = tsk
->thread
.debug
.bp
[1].insn
.arm
;
398 dump
->u_debugreg
[4] = tsk
->thread
.debug
.nsaved
;
400 if (dump
->start_stack
< 0x04000000)
401 dump
->u_ssize
= (0x04000000 - dump
->start_stack
) >> PAGE_SHIFT
;
404 dump
->u_fpvalid
= dump_fpu (regs
, &dump
->u_fp
);
406 EXPORT_SYMBOL(dump_thread
);
409 * Shuffle the argument into the correct register before calling the
410 * thread function. r1 is the thread argument, r2 is the pointer to
411 * the thread function, and r3 points to the exit function.
413 extern void kernel_thread_helper(void);
414 asm( ".section .text\n"
416 " .type kernel_thread_helper, #function\n"
417 "kernel_thread_helper:\n"
421 " .size kernel_thread_helper, . - kernel_thread_helper\n"
425 * Create a kernel thread.
427 pid_t
kernel_thread(int (*fn
)(void *), void *arg
, unsigned long flags
)
431 memset(®s
, 0, sizeof(regs
));
433 regs
.ARM_r1
= (unsigned long)arg
;
434 regs
.ARM_r2
= (unsigned long)fn
;
435 regs
.ARM_r3
= (unsigned long)do_exit
;
436 regs
.ARM_pc
= (unsigned long)kernel_thread_helper
;
437 regs
.ARM_cpsr
= SVC_MODE
;
439 return do_fork(flags
|CLONE_VM
|CLONE_UNTRACED
, 0, ®s
, 0, NULL
, NULL
);
441 EXPORT_SYMBOL(kernel_thread
);
443 unsigned long get_wchan(struct task_struct
*p
)
445 unsigned long fp
, lr
;
446 unsigned long stack_start
, stack_end
;
448 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
451 stack_start
= (unsigned long)(p
->thread_info
+ 1);
452 stack_end
= ((unsigned long)p
->thread_info
) + THREAD_SIZE
;
454 fp
= thread_saved_fp(p
);
456 if (fp
< stack_start
|| fp
> stack_end
)
458 lr
= pc_pointer (((unsigned long *)fp
)[-1]);
459 if (!in_sched_functions(lr
))
461 fp
= *(unsigned long *) (fp
- 12);
462 } while (count
++ < 16);
465 EXPORT_SYMBOL(get_wchan
);