Linux Audio

Check our new training course

Loading...
v3.1
  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/module.h>
 14#include <linux/sched.h>
 15#include <linux/kernel.h>
 16#include <linux/mm.h>
 17#include <linux/stddef.h>
 18#include <linux/unistd.h>
 19#include <linux/user.h>
 20#include <linux/delay.h>
 21#include <linux/reboot.h>
 22#include <linux/interrupt.h>
 23#include <linux/kallsyms.h>
 24#include <linux/init.h>
 25#include <linux/cpu.h>
 26#include <linux/elfcore.h>
 27#include <linux/pm.h>
 28#include <linux/tick.h>
 29#include <linux/utsname.h>
 30#include <linux/uaccess.h>
 31#include <linux/random.h>
 32#include <linux/hw_breakpoint.h>
 33#include <linux/cpuidle.h>
 
 34
 35#include <asm/cacheflush.h>
 36#include <asm/leds.h>
 37#include <asm/processor.h>
 38#include <asm/system.h>
 39#include <asm/thread_notify.h>
 40#include <asm/stacktrace.h>
 
 41#include <asm/mach/time.h>
 
 42
 43#ifdef CONFIG_CC_STACKPROTECTOR
 44#include <linux/stackprotector.h>
 45unsigned long __stack_chk_guard __read_mostly;
 46EXPORT_SYMBOL(__stack_chk_guard);
 47#endif
 48
 49static const char *processor_modes[] = {
 50  "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
 51  "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
 52  "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
 53  "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
 54};
 55
 56static const char *isa_modes[] = {
 57  "ARM" , "Thumb" , "Jazelle", "ThumbEE"
 58};
 59
 60extern void setup_mm_for_reboot(char mode);
 61
 62static volatile int hlt_counter;
 63
 64#include <mach/system.h>
 
 
 
 
 
 
 
 65
 66void disable_hlt(void)
 67{
 68	hlt_counter++;
 69}
 70
 71EXPORT_SYMBOL(disable_hlt);
 
 72
 73void enable_hlt(void)
 74{
 75	hlt_counter--;
 76}
 77
 78EXPORT_SYMBOL(enable_hlt);
 
 79
 80static int __init nohlt_setup(char *__unused)
 81{
 82	hlt_counter = 1;
 83	return 1;
 84}
 85
 86static int __init hlt_setup(char *__unused)
 87{
 88	hlt_counter = 0;
 89	return 1;
 90}
 91
 92__setup("nohlt", nohlt_setup);
 93__setup("hlt", hlt_setup);
 
 94
 95void arm_machine_restart(char mode, const char *cmd)
 96{
 
 
 97	/* Disable interrupts first */
 98	local_irq_disable();
 99	local_fiq_disable();
100
101	/*
102	 * Tell the mm system that we are going to reboot -
103	 * we may need it to insert some 1:1 mappings so that
104	 * soft boot works.
105	 */
106	setup_mm_for_reboot(mode);
107
108	/* Clean and invalidate caches */
109	flush_cache_all();
110
111	/* Turn off caching */
112	cpu_proc_fin();
113
114	/* Push out any further dirty data, and ensure cache is empty */
115	flush_cache_all();
 
116
117	/*
118	 * Now call the architecture specific reboot code.
119	 */
120	arch_reset(mode, cmd);
121
122	/*
123	 * Whoops - the architecture was unable to reboot.
124	 * Tell the user!
125	 */
126	mdelay(1000);
127	printk("Reboot failed -- System halted\n");
128	while (1);
129}
130
131/*
132 * Function pointers to optional machine specific functions
133 */
134void (*pm_power_off)(void);
135EXPORT_SYMBOL(pm_power_off);
136
137void (*arm_pm_restart)(char str, const char *cmd) = arm_machine_restart;
138EXPORT_SYMBOL_GPL(arm_pm_restart);
139
140static void do_nothing(void *unused)
141{
142}
143
144/*
145 * cpu_idle_wait - Used to ensure that all the CPUs discard old value of
146 * pm_idle and update to new pm_idle value. Required while changing pm_idle
147 * handler on SMP systems.
148 *
149 * Caller must have changed pm_idle to the new value before the call. Old
150 * pm_idle value will not be used by any CPU after the return of this function.
151 */
152void cpu_idle_wait(void)
153{
154	smp_mb();
155	/* kick all the CPUs so that they exit out of pm_idle */
156	smp_call_function(do_nothing, NULL, 1);
157}
158EXPORT_SYMBOL_GPL(cpu_idle_wait);
159
160/*
161 * This is our default idle handler.  We need to disable
162 * interrupts here to ensure we don't miss a wakeup call.
163 */
164static void default_idle(void)
 
165{
166	if (!need_resched())
167		arch_idle();
 
 
168	local_irq_enable();
169}
170
171void (*pm_idle)(void) = default_idle;
172EXPORT_SYMBOL(pm_idle);
173
174/*
175 * The idle thread, has rather strange semantics for calling pm_idle,
176 * but this is what x86 does and we need to do the same, so that
177 * things like cpuidle get called in the same way.  The only difference
178 * is that we always respect 'hlt_counter' to prevent low power idle.
179 */
180void cpu_idle(void)
181{
182	local_fiq_enable();
 
183
184	/* endless idle loop with no priority at all */
185	while (1) {
186		tick_nohz_stop_sched_tick(1);
187		leds_event(led_idle_start);
188		while (!need_resched()) {
189#ifdef CONFIG_HOTPLUG_CPU
190			if (cpu_is_offline(smp_processor_id()))
191				cpu_die();
192#endif
193
194			local_irq_disable();
195			if (hlt_counter) {
196				local_irq_enable();
197				cpu_relax();
198			} else {
199				stop_critical_timings();
200				if (cpuidle_idle_call())
201					pm_idle();
202				start_critical_timings();
203				/*
204				 * This will eventually be removed - pm_idle
205				 * functions should always return with IRQs
206				 * enabled.
207				 */
208				WARN_ON(irqs_disabled());
209				local_irq_enable();
210			}
211		}
212		leds_event(led_idle_end);
213		tick_nohz_restart_sched_tick();
214		preempt_enable_no_resched();
215		schedule();
216		preempt_disable();
217	}
218}
219
220static char reboot_mode = 'h';
221
222int __init reboot_setup(char *str)
223{
224	reboot_mode = str[0];
225	return 1;
226}
227
228__setup("reboot=", reboot_setup);
 
 
 
 
 
229
 
 
 
 
 
 
 
 
 
230void machine_shutdown(void)
231{
232#ifdef CONFIG_SMP
233	smp_send_stop();
234#endif
235}
236
 
 
 
 
 
237void machine_halt(void)
238{
239	machine_shutdown();
 
 
 
240	while (1);
241}
242
 
 
 
 
 
 
243void machine_power_off(void)
244{
245	machine_shutdown();
 
 
246	if (pm_power_off)
247		pm_power_off();
248}
249
 
 
 
 
 
 
 
 
 
 
 
250void machine_restart(char *cmd)
251{
252	machine_shutdown();
 
 
253	arm_pm_restart(reboot_mode, cmd);
 
 
 
 
 
 
 
 
254}
255
256void __show_regs(struct pt_regs *regs)
257{
258	unsigned long flags;
259	char buf[64];
260
261	printk("CPU: %d    %s  (%s %.*s)\n",
262		raw_smp_processor_id(), print_tainted(),
263		init_utsname()->release,
264		(int)strcspn(init_utsname()->version, " "),
265		init_utsname()->version);
266	print_symbol("PC is at %s\n", instruction_pointer(regs));
267	print_symbol("LR is at %s\n", regs->ARM_lr);
268	printk("pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
269	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
270		regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
271		regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
272	printk("r10: %08lx  r9 : %08lx  r8 : %08lx\n",
273		regs->ARM_r10, regs->ARM_r9,
274		regs->ARM_r8);
275	printk("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
276		regs->ARM_r7, regs->ARM_r6,
277		regs->ARM_r5, regs->ARM_r4);
278	printk("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
279		regs->ARM_r3, regs->ARM_r2,
280		regs->ARM_r1, regs->ARM_r0);
281
282	flags = regs->ARM_cpsr;
283	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
284	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
285	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
286	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
287	buf[4] = '\0';
288
 
289	printk("Flags: %s  IRQs o%s  FIQs o%s  Mode %s  ISA %s  Segment %s\n",
290		buf, interrupts_enabled(regs) ? "n" : "ff",
291		fast_interrupts_enabled(regs) ? "n" : "ff",
292		processor_modes[processor_mode(regs)],
293		isa_modes[isa_mode(regs)],
294		get_fs() == get_ds() ? "kernel" : "user");
 
 
 
 
295#ifdef CONFIG_CPU_CP15
296	{
297		unsigned int ctrl;
298
299		buf[0] = '\0';
300#ifdef CONFIG_CPU_CP15_MMU
301		{
302			unsigned int transbase, dac;
303			asm("mrc p15, 0, %0, c2, c0\n\t"
304			    "mrc p15, 0, %1, c3, c0\n"
305			    : "=r" (transbase), "=r" (dac));
306			snprintf(buf, sizeof(buf), "  Table: %08x  DAC: %08x",
307			  	transbase, dac);
308		}
309#endif
310		asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
311
312		printk("Control: %08x%s\n", ctrl, buf);
313	}
314#endif
315}
316
317void show_regs(struct pt_regs * regs)
318{
319	printk("\n");
320	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
321	__show_regs(regs);
322	__backtrace();
323}
324
325ATOMIC_NOTIFIER_HEAD(thread_notify_head);
326
327EXPORT_SYMBOL_GPL(thread_notify_head);
328
329/*
330 * Free current thread data structures etc..
331 */
332void exit_thread(void)
333{
334	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
335}
336
337void flush_thread(void)
338{
339	struct thread_info *thread = current_thread_info();
340	struct task_struct *tsk = current;
341
342	flush_ptrace_hw_breakpoint(tsk);
343
344	memset(thread->used_cp, 0, sizeof(thread->used_cp));
345	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
346	memset(&thread->fpstate, 0, sizeof(union fp_state));
347
348	thread_notify(THREAD_NOTIFY_FLUSH, thread);
349}
350
351void release_thread(struct task_struct *dead_task)
352{
353}
354
355asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
356
357int
358copy_thread(unsigned long clone_flags, unsigned long stack_start,
359	    unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs)
360{
361	struct thread_info *thread = task_thread_info(p);
362	struct pt_regs *childregs = task_pt_regs(p);
363
364	*childregs = *regs;
365	childregs->ARM_r0 = 0;
366	childregs->ARM_sp = stack_start;
367
368	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
369	thread->cpu_context.sp = (unsigned long)childregs;
 
 
 
 
 
 
 
 
 
 
 
370	thread->cpu_context.pc = (unsigned long)ret_from_fork;
 
371
372	clear_ptrace_hw_breakpoint(p);
373
374	if (clone_flags & CLONE_SETTLS)
375		thread->tp_value = regs->ARM_r3;
 
376
377	thread_notify(THREAD_NOTIFY_COPY, thread);
378
379	return 0;
380}
381
382/*
383 * Fill in the task's elfregs structure for a core dump.
384 */
385int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
386{
387	elf_core_copy_regs(elfregs, task_pt_regs(t));
388	return 1;
389}
390
391/*
392 * fill in the fpe structure for a core dump...
393 */
394int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
395{
396	struct thread_info *thread = current_thread_info();
397	int used_math = thread->used_cp[1] | thread->used_cp[2];
398
399	if (used_math)
400		memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
401
402	return used_math != 0;
403}
404EXPORT_SYMBOL(dump_fpu);
405
406/*
407 * Shuffle the argument into the correct register before calling the
408 * thread function.  r4 is the thread argument, r5 is the pointer to
409 * the thread function, and r6 points to the exit function.
410 */
411extern void kernel_thread_helper(void);
412asm(	".pushsection .text\n"
413"	.align\n"
414"	.type	kernel_thread_helper, #function\n"
415"kernel_thread_helper:\n"
416#ifdef CONFIG_TRACE_IRQFLAGS
417"	bl	trace_hardirqs_on\n"
418#endif
419"	msr	cpsr_c, r7\n"
420"	mov	r0, r4\n"
421"	mov	lr, r6\n"
422"	mov	pc, r5\n"
423"	.size	kernel_thread_helper, . - kernel_thread_helper\n"
424"	.popsection");
425
426#ifdef CONFIG_ARM_UNWIND
427extern void kernel_thread_exit(long code);
428asm(	".pushsection .text\n"
429"	.align\n"
430"	.type	kernel_thread_exit, #function\n"
431"kernel_thread_exit:\n"
432"	.fnstart\n"
433"	.cantunwind\n"
434"	bl	do_exit\n"
435"	nop\n"
436"	.fnend\n"
437"	.size	kernel_thread_exit, . - kernel_thread_exit\n"
438"	.popsection");
439#else
440#define kernel_thread_exit	do_exit
441#endif
442
443/*
444 * Create a kernel thread.
445 */
446pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
447{
448	struct pt_regs regs;
449
450	memset(&regs, 0, sizeof(regs));
451
452	regs.ARM_r4 = (unsigned long)arg;
453	regs.ARM_r5 = (unsigned long)fn;
454	regs.ARM_r6 = (unsigned long)kernel_thread_exit;
455	regs.ARM_r7 = SVC_MODE | PSR_ENDSTATE | PSR_ISETSTATE;
456	regs.ARM_pc = (unsigned long)kernel_thread_helper;
457	regs.ARM_cpsr = regs.ARM_r7 | PSR_I_BIT;
458
459	return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
460}
461EXPORT_SYMBOL(kernel_thread);
462
463unsigned long get_wchan(struct task_struct *p)
464{
465	struct stackframe frame;
 
466	int count = 0;
467	if (!p || p == current || p->state == TASK_RUNNING)
468		return 0;
469
470	frame.fp = thread_saved_fp(p);
471	frame.sp = thread_saved_sp(p);
472	frame.lr = 0;			/* recovered from the stack */
473	frame.pc = thread_saved_pc(p);
 
474	do {
475		int ret = unwind_frame(&frame);
476		if (ret < 0)
 
477			return 0;
478		if (!in_sched_functions(frame.pc))
479			return frame.pc;
480	} while (count ++ < 16);
481	return 0;
482}
483
484unsigned long arch_randomize_brk(struct mm_struct *mm)
485{
486	unsigned long range_end = mm->brk + 0x02000000;
487	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
488}
489
490#ifdef CONFIG_MMU
 
491/*
492 * The vectors page is always readable from user space for the
493 * atomic helpers and the signal restart code.  Let's declare a mapping
494 * for it so it is visible through ptrace and /proc/<pid>/mem.
495 */
 
 
 
 
 
496
497int vectors_user_mapping(void)
498{
499	struct mm_struct *mm = current->mm;
500	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
501				       VM_READ | VM_EXEC |
502				       VM_MAYREAD | VM_MAYEXEC |
503				       VM_ALWAYSDUMP | VM_RESERVED,
504				       NULL);
 
 
505}
506
 
 
 
 
 
 
 
 
 
 
 
 
 
 
507const char *arch_vma_name(struct vm_area_struct *vma)
508{
509	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
510}
511#endif
v3.15
  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/export.h>
 14#include <linux/sched.h>
 15#include <linux/kernel.h>
 16#include <linux/mm.h>
 17#include <linux/stddef.h>
 18#include <linux/unistd.h>
 19#include <linux/user.h>
 20#include <linux/delay.h>
 21#include <linux/reboot.h>
 22#include <linux/interrupt.h>
 23#include <linux/kallsyms.h>
 24#include <linux/init.h>
 25#include <linux/cpu.h>
 26#include <linux/elfcore.h>
 27#include <linux/pm.h>
 28#include <linux/tick.h>
 29#include <linux/utsname.h>
 30#include <linux/uaccess.h>
 31#include <linux/random.h>
 32#include <linux/hw_breakpoint.h>
 33#include <linux/leds.h>
 34#include <linux/reboot.h>
 35
 36#include <asm/cacheflush.h>
 37#include <asm/idmap.h>
 38#include <asm/processor.h>
 
 39#include <asm/thread_notify.h>
 40#include <asm/stacktrace.h>
 41#include <asm/system_misc.h>
 42#include <asm/mach/time.h>
 43#include <asm/tls.h>
 44
 45#ifdef CONFIG_CC_STACKPROTECTOR
 46#include <linux/stackprotector.h>
 47unsigned long __stack_chk_guard __read_mostly;
 48EXPORT_SYMBOL(__stack_chk_guard);
 49#endif
 50
 51static const char *processor_modes[] __maybe_unused = {
 52  "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
 53  "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
 54  "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
 55  "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
 56};
 57
 58static const char *isa_modes[] __maybe_unused = {
 59  "ARM" , "Thumb" , "Jazelle", "ThumbEE"
 60};
 61
 62extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
 63typedef void (*phys_reset_t)(unsigned long);
 
 64
 65/*
 66 * A temporary stack to use for CPU reset. This is static so that we
 67 * don't clobber it with the identity mapping. When running with this
 68 * stack, any references to the current task *will not work* so you
 69 * should really do as little as possible before jumping to your reset
 70 * code.
 71 */
 72static u64 soft_restart_stack[16];
 73
 74static void __soft_restart(void *addr)
 75{
 76	phys_reset_t phys_reset;
 
 77
 78	/* Take out a flat memory mapping. */
 79	setup_mm_for_reboot();
 80
 81	/* Clean and invalidate caches */
 82	flush_cache_all();
 
 
 83
 84	/* Turn off caching */
 85	cpu_proc_fin();
 86
 87	/* Push out any further dirty data, and ensure cache is empty */
 88	flush_cache_all();
 
 
 
 89
 90	/* Switch to the identity mapping. */
 91	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
 92	phys_reset((unsigned long)addr);
 
 
 93
 94	/* Should never get here. */
 95	BUG();
 96}
 97
 98void soft_restart(unsigned long addr)
 99{
100	u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
101
102	/* Disable interrupts first */
103	raw_local_irq_disable();
104	local_fiq_disable();
105
106	/* Disable the L2 if we're the last man standing. */
107	if (num_online_cpus() == 1)
108		outer_disable();
 
 
 
 
 
 
109
110	/* Change to the new stack and continue with the reset. */
111	call_with_stack(__soft_restart, (void *)addr, (void *)stack);
112
113	/* Should never get here. */
114	BUG();
115}
116
117static void null_restart(enum reboot_mode reboot_mode, const char *cmd)
118{
 
 
 
 
 
 
 
 
 
 
119}
120
121/*
122 * Function pointers to optional machine specific functions
123 */
124void (*pm_power_off)(void);
125EXPORT_SYMBOL(pm_power_off);
126
127void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd) = null_restart;
128EXPORT_SYMBOL_GPL(arm_pm_restart);
129
 
 
 
 
130/*
131 * This is our default idle handler.
 
 
 
 
 
132 */
133
134void (*arm_pm_idle)(void);
 
 
 
 
 
135
136/*
137 * Called from the core idle loop.
 
138 */
139
140void arch_cpu_idle(void)
141{
142	if (arm_pm_idle)
143		arm_pm_idle();
144	else
145		cpu_do_idle();
146	local_irq_enable();
147}
148
149void arch_cpu_idle_prepare(void)
 
 
 
 
 
 
 
 
 
150{
151	local_fiq_enable();
152}
153
154void arch_cpu_idle_enter(void)
155{
156	ledtrig_cpu(CPU_LED_IDLE_START);
157#ifdef CONFIG_PL310_ERRATA_769419
158	wmb();
 
 
 
159#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
160}
161
162void arch_cpu_idle_exit(void)
 
 
163{
164	ledtrig_cpu(CPU_LED_IDLE_END);
 
165}
166
167#ifdef CONFIG_HOTPLUG_CPU
168void arch_cpu_idle_dead(void)
169{
170	cpu_die();
171}
172#endif
173
174/*
175 * Called by kexec, immediately prior to machine_kexec().
176 *
177 * This must completely disable all secondary CPUs; simply causing those CPUs
178 * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
179 * kexec'd kernel to use any and all RAM as it sees fit, without having to
180 * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
181 * functionality embodied in disable_nonboot_cpus() to achieve this.
182 */
183void machine_shutdown(void)
184{
185	disable_nonboot_cpus();
 
 
186}
187
188/*
189 * Halting simply requires that the secondary CPUs stop performing any
190 * activity (executing tasks, handling interrupts). smp_send_stop()
191 * achieves this.
192 */
193void machine_halt(void)
194{
195	local_irq_disable();
196	smp_send_stop();
197
198	local_irq_disable();
199	while (1);
200}
201
202/*
203 * Power-off simply requires that the secondary CPUs stop performing any
204 * activity (executing tasks, handling interrupts). smp_send_stop()
205 * achieves this. When the system power is turned off, it will take all CPUs
206 * with it.
207 */
208void machine_power_off(void)
209{
210	local_irq_disable();
211	smp_send_stop();
212
213	if (pm_power_off)
214		pm_power_off();
215}
216
217/*
218 * Restart requires that the secondary CPUs stop performing any activity
219 * while the primary CPU resets the system. Systems with a single CPU can
220 * use soft_restart() as their machine descriptor's .restart hook, since that
221 * will cause the only available CPU to reset. Systems with multiple CPUs must
222 * provide a HW restart implementation, to ensure that all CPUs reset at once.
223 * This is required so that any code running after reset on the primary CPU
224 * doesn't have to co-ordinate with other CPUs to ensure they aren't still
225 * executing pre-reset code, and using RAM that the primary CPU's code wishes
226 * to use. Implementing such co-ordination would be essentially impossible.
227 */
228void machine_restart(char *cmd)
229{
230	local_irq_disable();
231	smp_send_stop();
232
233	arm_pm_restart(reboot_mode, cmd);
234
235	/* Give a grace period for failure to restart of 1s */
236	mdelay(1000);
237
238	/* Whoops - the platform was unable to reboot. Tell the user! */
239	printk("Reboot failed -- System halted\n");
240	local_irq_disable();
241	while (1);
242}
243
244void __show_regs(struct pt_regs *regs)
245{
246	unsigned long flags;
247	char buf[64];
248
249	show_regs_print_info(KERN_DEFAULT);
250
 
 
 
251	print_symbol("PC is at %s\n", instruction_pointer(regs));
252	print_symbol("LR is at %s\n", regs->ARM_lr);
253	printk("pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
254	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
255		regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
256		regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
257	printk("r10: %08lx  r9 : %08lx  r8 : %08lx\n",
258		regs->ARM_r10, regs->ARM_r9,
259		regs->ARM_r8);
260	printk("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
261		regs->ARM_r7, regs->ARM_r6,
262		regs->ARM_r5, regs->ARM_r4);
263	printk("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
264		regs->ARM_r3, regs->ARM_r2,
265		regs->ARM_r1, regs->ARM_r0);
266
267	flags = regs->ARM_cpsr;
268	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
269	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
270	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
271	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
272	buf[4] = '\0';
273
274#ifndef CONFIG_CPU_V7M
275	printk("Flags: %s  IRQs o%s  FIQs o%s  Mode %s  ISA %s  Segment %s\n",
276		buf, interrupts_enabled(regs) ? "n" : "ff",
277		fast_interrupts_enabled(regs) ? "n" : "ff",
278		processor_modes[processor_mode(regs)],
279		isa_modes[isa_mode(regs)],
280		get_fs() == get_ds() ? "kernel" : "user");
281#else
282	printk("xPSR: %08lx\n", regs->ARM_cpsr);
283#endif
284
285#ifdef CONFIG_CPU_CP15
286	{
287		unsigned int ctrl;
288
289		buf[0] = '\0';
290#ifdef CONFIG_CPU_CP15_MMU
291		{
292			unsigned int transbase, dac;
293			asm("mrc p15, 0, %0, c2, c0\n\t"
294			    "mrc p15, 0, %1, c3, c0\n"
295			    : "=r" (transbase), "=r" (dac));
296			snprintf(buf, sizeof(buf), "  Table: %08x  DAC: %08x",
297			  	transbase, dac);
298		}
299#endif
300		asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
301
302		printk("Control: %08x%s\n", ctrl, buf);
303	}
304#endif
305}
306
307void show_regs(struct pt_regs * regs)
308{
309	printk("\n");
 
310	__show_regs(regs);
311	dump_stack();
312}
313
314ATOMIC_NOTIFIER_HEAD(thread_notify_head);
315
316EXPORT_SYMBOL_GPL(thread_notify_head);
317
318/*
319 * Free current thread data structures etc..
320 */
321void exit_thread(void)
322{
323	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
324}
325
326void flush_thread(void)
327{
328	struct thread_info *thread = current_thread_info();
329	struct task_struct *tsk = current;
330
331	flush_ptrace_hw_breakpoint(tsk);
332
333	memset(thread->used_cp, 0, sizeof(thread->used_cp));
334	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
335	memset(&thread->fpstate, 0, sizeof(union fp_state));
336
337	thread_notify(THREAD_NOTIFY_FLUSH, thread);
338}
339
340void release_thread(struct task_struct *dead_task)
341{
342}
343
344asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
345
346int
347copy_thread(unsigned long clone_flags, unsigned long stack_start,
348	    unsigned long stk_sz, struct task_struct *p)
349{
350	struct thread_info *thread = task_thread_info(p);
351	struct pt_regs *childregs = task_pt_regs(p);
352
 
 
 
 
353	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
354
355	if (likely(!(p->flags & PF_KTHREAD))) {
356		*childregs = *current_pt_regs();
357		childregs->ARM_r0 = 0;
358		if (stack_start)
359			childregs->ARM_sp = stack_start;
360	} else {
361		memset(childregs, 0, sizeof(struct pt_regs));
362		thread->cpu_context.r4 = stk_sz;
363		thread->cpu_context.r5 = stack_start;
364		childregs->ARM_cpsr = SVC_MODE;
365	}
366	thread->cpu_context.pc = (unsigned long)ret_from_fork;
367	thread->cpu_context.sp = (unsigned long)childregs;
368
369	clear_ptrace_hw_breakpoint(p);
370
371	if (clone_flags & CLONE_SETTLS)
372		thread->tp_value[0] = childregs->ARM_r3;
373	thread->tp_value[1] = get_tpuser();
374
375	thread_notify(THREAD_NOTIFY_COPY, thread);
376
377	return 0;
378}
379
380/*
381 * Fill in the task's elfregs structure for a core dump.
382 */
383int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
384{
385	elf_core_copy_regs(elfregs, task_pt_regs(t));
386	return 1;
387}
388
389/*
390 * fill in the fpe structure for a core dump...
391 */
392int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
393{
394	struct thread_info *thread = current_thread_info();
395	int used_math = thread->used_cp[1] | thread->used_cp[2];
396
397	if (used_math)
398		memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
399
400	return used_math != 0;
401}
402EXPORT_SYMBOL(dump_fpu);
403
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
404unsigned long get_wchan(struct task_struct *p)
405{
406	struct stackframe frame;
407	unsigned long stack_page;
408	int count = 0;
409	if (!p || p == current || p->state == TASK_RUNNING)
410		return 0;
411
412	frame.fp = thread_saved_fp(p);
413	frame.sp = thread_saved_sp(p);
414	frame.lr = 0;			/* recovered from the stack */
415	frame.pc = thread_saved_pc(p);
416	stack_page = (unsigned long)task_stack_page(p);
417	do {
418		if (frame.sp < stack_page ||
419		    frame.sp >= stack_page + THREAD_SIZE ||
420		    unwind_frame(&frame) < 0)
421			return 0;
422		if (!in_sched_functions(frame.pc))
423			return frame.pc;
424	} while (count ++ < 16);
425	return 0;
426}
427
428unsigned long arch_randomize_brk(struct mm_struct *mm)
429{
430	unsigned long range_end = mm->brk + 0x02000000;
431	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
432}
433
434#ifdef CONFIG_MMU
435#ifdef CONFIG_KUSER_HELPERS
436/*
437 * The vectors page is always readable from user space for the
438 * atomic helpers. Insert it into the gate_vma so that it is visible
439 * through ptrace and /proc/<pid>/mem.
440 */
441static struct vm_area_struct gate_vma = {
442	.vm_start	= 0xffff0000,
443	.vm_end		= 0xffff0000 + PAGE_SIZE,
444	.vm_flags	= VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC,
445};
446
447static int __init gate_vma_init(void)
448{
449	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
450	return 0;
451}
452arch_initcall(gate_vma_init);
453
454struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
455{
456	return &gate_vma;
457}
458
459int in_gate_area(struct mm_struct *mm, unsigned long addr)
460{
461	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
462}
463
464int in_gate_area_no_mm(unsigned long addr)
465{
466	return in_gate_area(NULL, addr);
467}
468#define is_gate_vma(vma)	((vma) == &gate_vma)
469#else
470#define is_gate_vma(vma)	0
471#endif
472
473const char *arch_vma_name(struct vm_area_struct *vma)
474{
475	return is_gate_vma(vma) ? "[vectors]" :
476		(vma->vm_mm && vma->vm_start == vma->vm_mm->context.sigpage) ?
477		 "[sigpage]" : NULL;
478}
479
480static struct page *signal_page;
481extern struct page *get_signal_page(void);
482
483int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
484{
485	struct mm_struct *mm = current->mm;
486	unsigned long addr;
487	int ret;
488
489	if (!signal_page)
490		signal_page = get_signal_page();
491	if (!signal_page)
492		return -ENOMEM;
493
494	down_write(&mm->mmap_sem);
495	addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
496	if (IS_ERR_VALUE(addr)) {
497		ret = addr;
498		goto up_fail;
499	}
500
501	ret = install_special_mapping(mm, addr, PAGE_SIZE,
502		VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
503		&signal_page);
504
505	if (ret == 0)
506		mm->context.sigpage = addr;
507
508 up_fail:
509	up_write(&mm->mmap_sem);
510	return ret;
511}
512#endif