xref: /xnu-11417.140.69/osfmk/arm/cpu_common.c (revision 43a90889846e00bfb5cf1d255cdc0a701a1e05a4)
1 /*
2  * Copyright (c) 2017-2019 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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23  * Please see the License for the specific language governing rights and
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25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*
29  *	File:	arm/cpu_common.c
30  *
31  *	cpu routines common to all supported arm variants
32  */
33 
34 #include <kern/machine.h>
35 #include <kern/cpu_number.h>
36 #include <kern/thread.h>
37 #include <kern/percpu.h>
38 #include <kern/timer_queue.h>
39 #include <kern/locks.h>
40 #include <kern/clock.h>
41 #include <arm/cpu_data.h>
42 #include <arm/cpuid.h>
43 #include <arm/caches_internal.h>
44 #include <arm/cpu_data_internal.h>
45 #include <arm/cpu_internal.h>
46 #include <arm/misc_protos.h>
47 #include <arm/machine_cpu.h>
48 #include <arm/rtclock.h>
49 #include <mach/processor_info.h>
50 #include <machine/atomic.h>
51 #include <machine/config.h>
52 #include <vm/vm_kern_xnu.h>
53 #include <vm/vm_map.h>
54 #include <pexpert/arm/protos.h>
55 #include <pexpert/device_tree.h>
56 #include <sys/kdebug.h>
57 #include <arm/machine_routines.h>
58 #include <arm64/proc_reg.h>
59 #include <libkern/OSAtomic.h>
60 
61 SECURITY_READ_ONLY_LATE(struct percpu_base) percpu_base;
62 vm_address_t     percpu_base_cur;
63 cpu_data_t       PERCPU_DATA(cpu_data);
64 cpu_data_entry_t CpuDataEntries[MAX_CPUS];
65 
66 static LCK_GRP_DECLARE(cpu_lck_grp, "cpu_lck_grp");
67 static LCK_RW_DECLARE(cpu_state_lock, &cpu_lck_grp);
68 static LCK_MTX_DECLARE(cpu_xcall_mtx, &cpu_lck_grp);
69 
70 unsigned int    real_ncpus = 1;
71 boolean_t       idle_enable = FALSE;
72 uint64_t        wake_abstime = 0x0ULL;
73 
74 extern uint64_t xcall_ack_timeout_abstime;
75 
76 #if defined(HAS_IPI)
77 extern unsigned int gFastIPI;
78 #endif /* defined(HAS_IPI) */
79 
80 cpu_data_t *
cpu_datap(int cpu)81 cpu_datap(int cpu)
82 {
83 	assert(cpu <= ml_get_max_cpu_number());
84 	return CpuDataEntries[cpu].cpu_data_vaddr;
85 }
86 
87 kern_return_t
cpu_control(int slot_num,processor_info_t info,unsigned int count)88 cpu_control(int slot_num,
89     processor_info_t info,
90     unsigned int count)
91 {
92 	printf("cpu_control(%d,%p,%d) not implemented\n",
93 	    slot_num, info, count);
94 	return KERN_FAILURE;
95 }
96 
97 kern_return_t
cpu_info_count(processor_flavor_t flavor,unsigned int * count)98 cpu_info_count(processor_flavor_t flavor,
99     unsigned int *count)
100 {
101 	switch (flavor) {
102 	case PROCESSOR_CPU_STAT:
103 		*count = PROCESSOR_CPU_STAT_COUNT;
104 		return KERN_SUCCESS;
105 
106 	case PROCESSOR_CPU_STAT64:
107 		*count = PROCESSOR_CPU_STAT64_COUNT;
108 		return KERN_SUCCESS;
109 
110 	default:
111 		*count = 0;
112 		return KERN_FAILURE;
113 	}
114 }
115 
116 kern_return_t
cpu_info(processor_flavor_t flavor,int slot_num,processor_info_t info,unsigned int * count)117 cpu_info(processor_flavor_t flavor, int slot_num, processor_info_t info,
118     unsigned int *count)
119 {
120 	cpu_data_t *cpu_data_ptr = CpuDataEntries[slot_num].cpu_data_vaddr;
121 
122 	switch (flavor) {
123 	case PROCESSOR_CPU_STAT:
124 	{
125 		if (*count < PROCESSOR_CPU_STAT_COUNT) {
126 			return KERN_FAILURE;
127 		}
128 
129 		processor_cpu_stat_t cpu_stat = (processor_cpu_stat_t)info;
130 		cpu_stat->irq_ex_cnt = (uint32_t)cpu_data_ptr->cpu_stat.irq_ex_cnt;
131 		cpu_stat->ipi_cnt = (uint32_t)cpu_data_ptr->cpu_stat.ipi_cnt;
132 		cpu_stat->timer_cnt = (uint32_t)cpu_data_ptr->cpu_stat.timer_cnt;
133 		cpu_stat->undef_ex_cnt = (uint32_t)cpu_data_ptr->cpu_stat.undef_ex_cnt;
134 		cpu_stat->unaligned_cnt = (uint32_t)cpu_data_ptr->cpu_stat.unaligned_cnt;
135 		cpu_stat->vfp_cnt = (uint32_t)cpu_data_ptr->cpu_stat.vfp_cnt;
136 		cpu_stat->vfp_shortv_cnt = 0;
137 		cpu_stat->data_ex_cnt = (uint32_t)cpu_data_ptr->cpu_stat.data_ex_cnt;
138 		cpu_stat->instr_ex_cnt = (uint32_t)cpu_data_ptr->cpu_stat.instr_ex_cnt;
139 
140 		*count = PROCESSOR_CPU_STAT_COUNT;
141 
142 		return KERN_SUCCESS;
143 	}
144 
145 	case PROCESSOR_CPU_STAT64:
146 	{
147 		if (*count < PROCESSOR_CPU_STAT64_COUNT) {
148 			return KERN_FAILURE;
149 		}
150 
151 		processor_cpu_stat64_t cpu_stat = (processor_cpu_stat64_t)info;
152 		cpu_stat->irq_ex_cnt = cpu_data_ptr->cpu_stat.irq_ex_cnt;
153 		cpu_stat->ipi_cnt = cpu_data_ptr->cpu_stat.ipi_cnt;
154 		cpu_stat->timer_cnt = cpu_data_ptr->cpu_stat.timer_cnt;
155 		cpu_stat->undef_ex_cnt = cpu_data_ptr->cpu_stat.undef_ex_cnt;
156 		cpu_stat->unaligned_cnt = cpu_data_ptr->cpu_stat.unaligned_cnt;
157 		cpu_stat->vfp_cnt = cpu_data_ptr->cpu_stat.vfp_cnt;
158 		cpu_stat->vfp_shortv_cnt = 0;
159 		cpu_stat->data_ex_cnt = cpu_data_ptr->cpu_stat.data_ex_cnt;
160 		cpu_stat->instr_ex_cnt = cpu_data_ptr->cpu_stat.instr_ex_cnt;
161 #if CONFIG_CPU_COUNTERS
162 		cpu_stat->pmi_cnt = cpu_data_ptr->cpu_monotonic.mtc_npmis;
163 #endif /* CONFIG_CPU_COUNTERS */
164 
165 		*count = PROCESSOR_CPU_STAT64_COUNT;
166 
167 		return KERN_SUCCESS;
168 	}
169 
170 	default:
171 		return KERN_FAILURE;
172 	}
173 }
174 
175 /*
176  *	Routine:	cpu_doshutdown
177  *	Function:
178  */
179 void
cpu_doshutdown(void (* doshutdown)(processor_t),processor_t processor)180 cpu_doshutdown(void (*doshutdown)(processor_t),
181     processor_t processor)
182 {
183 	doshutdown(processor);
184 }
185 
186 /*
187  *	Routine:	cpu_idle_tickle
188  *
189  */
190 void
cpu_idle_tickle(void)191 cpu_idle_tickle(void)
192 {
193 	boolean_t       intr;
194 	cpu_data_t      *cpu_data_ptr;
195 	uint64_t        new_idle_timeout_ticks = 0x0ULL;
196 
197 	intr = ml_set_interrupts_enabled(FALSE);
198 	cpu_data_ptr = getCpuDatap();
199 
200 	if (cpu_data_ptr->idle_timer_notify != NULL) {
201 		cpu_data_ptr->idle_timer_notify(cpu_data_ptr->idle_timer_refcon, &new_idle_timeout_ticks);
202 		if (new_idle_timeout_ticks != 0x0ULL) {
203 			/* if a new idle timeout was requested set the new idle timer deadline */
204 			clock_absolutetime_interval_to_deadline(new_idle_timeout_ticks, &cpu_data_ptr->idle_timer_deadline);
205 		} else {
206 			/* turn off the idle timer */
207 			cpu_data_ptr->idle_timer_deadline = 0x0ULL;
208 		}
209 		timer_resync_deadlines();
210 	}
211 	(void) ml_set_interrupts_enabled(intr);
212 }
213 
214 static void
cpu_handle_xcall(cpu_data_t * cpu_data_ptr)215 cpu_handle_xcall(cpu_data_t *cpu_data_ptr)
216 {
217 	broadcastFunc   xfunc;
218 	void            *xparam;
219 
220 	os_atomic_thread_fence(acquire);
221 	/* Come back around if cpu_signal_internal is running on another CPU and has just
222 	* added SIGPxcall to the pending mask, but hasn't yet assigned the call params.*/
223 	if (cpu_data_ptr->cpu_xcall_p0 != NULL && cpu_data_ptr->cpu_xcall_p1 != NULL) {
224 		xfunc = ptrauth_auth_function(cpu_data_ptr->cpu_xcall_p0, ptrauth_key_function_pointer, cpu_data_ptr);
225 		INTERRUPT_MASKED_DEBUG_START(xfunc, DBG_INTR_TYPE_IPI);
226 		xparam = cpu_data_ptr->cpu_xcall_p1;
227 		cpu_data_ptr->cpu_xcall_p0 = NULL;
228 		cpu_data_ptr->cpu_xcall_p1 = NULL;
229 		os_atomic_thread_fence(acq_rel);
230 		os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPxcall, relaxed);
231 		xfunc(xparam);
232 		INTERRUPT_MASKED_DEBUG_END();
233 	}
234 	if (cpu_data_ptr->cpu_imm_xcall_p0 != NULL && cpu_data_ptr->cpu_imm_xcall_p1 != NULL) {
235 		xfunc = ptrauth_auth_function(cpu_data_ptr->cpu_imm_xcall_p0, ptrauth_key_function_pointer, cpu_data_ptr);
236 		INTERRUPT_MASKED_DEBUG_START(xfunc, DBG_INTR_TYPE_IPI);
237 		xparam = cpu_data_ptr->cpu_imm_xcall_p1;
238 		cpu_data_ptr->cpu_imm_xcall_p0 = NULL;
239 		cpu_data_ptr->cpu_imm_xcall_p1 = NULL;
240 		os_atomic_thread_fence(acq_rel);
241 		os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPxcallImm, relaxed);
242 		xfunc(xparam);
243 		INTERRUPT_MASKED_DEBUG_END();
244 	}
245 }
246 
247 static unsigned int
cpu_broadcast_xcall_internal(unsigned int signal,uint32_t * synch,boolean_t self_xcall,broadcastFunc func,void * parm)248 cpu_broadcast_xcall_internal(unsigned int signal,
249     uint32_t *synch,
250     boolean_t self_xcall,
251     broadcastFunc func,
252     void *parm)
253 {
254 	boolean_t       intr;
255 	cpu_data_t      *cpu_data_ptr;
256 	cpu_data_t      *target_cpu_datap;
257 	unsigned int    failsig;
258 	int             cpu;
259 	int             max_cpu = ml_get_max_cpu_number() + 1;
260 
261 	//yes, param ALSO cannot be NULL
262 	assert(synch);
263 	assert(func);
264 	assert(parm);
265 
266 	lck_mtx_lock(&cpu_xcall_mtx);
267 	intr = ml_set_interrupts_enabled(FALSE);
268 	cpu_data_ptr = getCpuDatap();
269 
270 	failsig = 0;
271 
272 	*synch = max_cpu;
273 	assert_wait((event_t)synch, THREAD_UNINT);
274 
275 	for (cpu = 0; cpu < max_cpu; cpu++) {
276 		target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
277 
278 		if (target_cpu_datap == cpu_data_ptr) {
279 			continue;
280 		}
281 
282 		if ((target_cpu_datap == NULL) ||
283 		    KERN_SUCCESS != cpu_signal(target_cpu_datap, signal, ptrauth_nop_cast(void*, ptrauth_auth_and_resign(func, ptrauth_key_function_pointer, ptrauth_type_discriminator(broadcastFunc), ptrauth_key_function_pointer, target_cpu_datap)), parm)) {
284 			failsig++;
285 		}
286 	}
287 
288 	if (self_xcall) {
289 		func(parm);
290 	}
291 
292 	(void) ml_set_interrupts_enabled(intr);
293 
294 	if (os_atomic_sub(synch, (!self_xcall) ? failsig + 1 : failsig, relaxed) == 0) {
295 		clear_wait(current_thread(), THREAD_AWAKENED);
296 	} else {
297 		thread_block(THREAD_CONTINUE_NULL);
298 	}
299 	lck_mtx_unlock(&cpu_xcall_mtx);
300 
301 	if (!self_xcall) {
302 		return max_cpu - failsig - 1;
303 	} else {
304 		return max_cpu - failsig;
305 	}
306 }
307 
308 unsigned int
cpu_broadcast_xcall(uint32_t * synch,boolean_t self_xcall,broadcastFunc func,void * parm)309 cpu_broadcast_xcall(uint32_t *synch,
310     boolean_t self_xcall,
311     broadcastFunc func,
312     void *parm)
313 {
314 	return cpu_broadcast_xcall_internal(SIGPxcall, synch, self_xcall, func, parm);
315 }
316 
317 struct cpu_broadcast_xcall_simple_data {
318 	broadcastFunc func;
319 	void* parm;
320 	uint32_t sync;
321 };
322 
323 static void
cpu_broadcast_xcall_simple_cbk(void * parm)324 cpu_broadcast_xcall_simple_cbk(void *parm)
325 {
326 	struct cpu_broadcast_xcall_simple_data *data = (struct cpu_broadcast_xcall_simple_data*)parm;
327 
328 	data->func(data->parm);
329 
330 	if (os_atomic_dec(&data->sync, relaxed) == 0) {
331 		thread_wakeup((event_t)&data->sync);
332 	}
333 }
334 
335 static unsigned int
cpu_xcall_simple(boolean_t self_xcall,broadcastFunc func,void * parm,bool immediate)336 cpu_xcall_simple(boolean_t self_xcall,
337     broadcastFunc func,
338     void *parm,
339     bool immediate)
340 {
341 	struct cpu_broadcast_xcall_simple_data data = {};
342 
343 	data.func = func;
344 	data.parm = parm;
345 
346 	return cpu_broadcast_xcall_internal(immediate ? SIGPxcallImm : SIGPxcall, &data.sync, self_xcall, cpu_broadcast_xcall_simple_cbk, &data);
347 }
348 
349 unsigned int
cpu_broadcast_xcall_simple(boolean_t self_xcall,broadcastFunc func,void * parm)350 cpu_broadcast_xcall_simple(boolean_t self_xcall,
351     broadcastFunc func,
352     void *parm)
353 {
354 	return cpu_xcall_simple(self_xcall, func, parm, false);
355 }
356 
357 static kern_return_t
cpu_xcall_internal(unsigned int signal,int cpu_number,broadcastFunc func,void * param)358 cpu_xcall_internal(unsigned int signal, int cpu_number, broadcastFunc func, void *param)
359 {
360 	cpu_data_t      *target_cpu_datap;
361 
362 	if ((cpu_number < 0) || (cpu_number > ml_get_max_cpu_number())) {
363 		panic("cpu_xcall_internal: invalid cpu_number %d", cpu_number);
364 	}
365 
366 	if (func == NULL || param == NULL) {
367 		// cpu_handle_xcall uses non-NULL-ness to tell when the value is ready
368 		panic("cpu_xcall_internal: cannot have null func/param: %p %p", func, param);
369 	}
370 
371 	target_cpu_datap = (cpu_data_t*)CpuDataEntries[cpu_number].cpu_data_vaddr;
372 	if (target_cpu_datap == NULL) {
373 		panic("cpu_xcall_internal: cpu %d not initialized", cpu_number);
374 	}
375 
376 	return cpu_signal(target_cpu_datap, signal, ptrauth_nop_cast(void*, ptrauth_auth_and_resign(func, ptrauth_key_function_pointer, ptrauth_type_discriminator(broadcastFunc), ptrauth_key_function_pointer, target_cpu_datap)), param);
377 }
378 
379 kern_return_t
cpu_xcall(int cpu_number,broadcastFunc func,void * param)380 cpu_xcall(int cpu_number, broadcastFunc func, void *param)
381 {
382 	return cpu_xcall_internal(SIGPxcall, cpu_number, func, param);
383 }
384 
385 kern_return_t
cpu_immediate_xcall(int cpu_number,broadcastFunc func,void * param)386 cpu_immediate_xcall(int cpu_number, broadcastFunc func, void *param)
387 {
388 	return cpu_xcall_internal(SIGPxcallImm, cpu_number, func, param);
389 }
390 
391 static kern_return_t
cpu_signal_internal(cpu_data_t * target_proc,cpu_signal_t signal,void * p0,void * p1,boolean_t defer)392 cpu_signal_internal(cpu_data_t *target_proc,
393     cpu_signal_t signal,
394     void *p0,
395     void *p1,
396     boolean_t defer)
397 {
398 	cpu_signal_t    current_signals;
399 	bool            swap_success;
400 	boolean_t       interruptible = ml_set_interrupts_enabled(FALSE);
401 	cpu_data_t      *current_proc = getCpuDatap();
402 
403 	/* We'll mandate that only IPIs meant to kick a core out of idle may ever be deferred. */
404 	if (defer) {
405 		assert(signal == SIGPnop || signal == SIGPdeferred);
406 	}
407 
408 	if ((signal == SIGPxcall) || (signal == SIGPxcallImm)) {
409 		uint64_t start_mabs_time, max_mabs_time, current_mabs_time;
410 		current_mabs_time = start_mabs_time = mach_absolute_time();
411 		max_mabs_time = xcall_ack_timeout_abstime + current_mabs_time;
412 		assert(max_mabs_time > current_mabs_time);
413 
414 		do {
415 			current_signals = target_proc->cpu_signal;
416 			if ((current_signals & SIGPdisabled) == SIGPdisabled) {
417 				ml_set_interrupts_enabled(interruptible);
418 				return KERN_FAILURE;
419 			}
420 			swap_success = os_atomic_cmpxchg(&target_proc->cpu_signal, current_signals & (~signal),
421 			    current_signals | signal, release);
422 
423 			if (!swap_success && (signal == SIGPxcallImm) && (target_proc->cpu_signal & SIGPxcallImm)) {
424 				ml_set_interrupts_enabled(interruptible);
425 				return KERN_ALREADY_WAITING;
426 			}
427 
428 			/* Drain pending xcalls on this cpu; the CPU we're trying to xcall may in turn
429 			 * be trying to xcall us.  Since we have interrupts disabled that can deadlock,
430 			 * so break the deadlock by draining pending xcalls. */
431 			if (!swap_success && (current_proc->cpu_signal & signal)) {
432 				cpu_handle_xcall(current_proc);
433 			}
434 		} while (!swap_success && ((current_mabs_time = mach_absolute_time()) < max_mabs_time));
435 
436 		/*
437 		 * If we time out while waiting for the target CPU to respond, it's possible that no
438 		 * other CPU is available to handle the watchdog interrupt that would eventually trigger
439 		 * a panic. To prevent this from happening, we just panic here to flag this condition.
440 		 */
441 		if (__improbable(current_mabs_time >= max_mabs_time)) {
442 			uint64_t end_time_ns, xcall_ack_timeout_ns;
443 			absolutetime_to_nanoseconds(current_mabs_time - start_mabs_time, &end_time_ns);
444 			absolutetime_to_nanoseconds(xcall_ack_timeout_abstime, &xcall_ack_timeout_ns);
445 			panic("CPU%u has failed to respond to cross-call after %llu nanoseconds (timeout = %llu ns)",
446 			    target_proc->cpu_number, end_time_ns, xcall_ack_timeout_ns);
447 		}
448 
449 		if (signal == SIGPxcallImm) {
450 			target_proc->cpu_imm_xcall_p0 = p0;
451 			target_proc->cpu_imm_xcall_p1 = p1;
452 		} else {
453 			target_proc->cpu_xcall_p0 = p0;
454 			target_proc->cpu_xcall_p1 = p1;
455 		}
456 	} else {
457 		do {
458 			current_signals = target_proc->cpu_signal;
459 			if ((current_signals & SIGPdisabled) == SIGPdisabled) {
460 				if (current_proc == target_proc) {
461 					panic("cpu_signal of self while signals are disabled");
462 				}
463 				ml_set_interrupts_enabled(interruptible);
464 				return KERN_FAILURE;
465 			}
466 
467 			swap_success = os_atomic_cmpxchg(&target_proc->cpu_signal, current_signals,
468 			    current_signals | signal, release);
469 		} while (!swap_success);
470 	}
471 
472 	/*
473 	 * DSB is needed here to ensure prior stores to the pending signal mask and xcall params
474 	 * will be visible by the time the other cores are signaled.  The IPI mechanism on any
475 	 * given platform will very likely use either an MSR or a non-coherent store that would
476 	 * not be ordered by a simple DMB.
477 	 */
478 	__builtin_arm_dsb(DSB_ISHST);
479 
480 	if (!(target_proc->cpu_signal & SIGPdisabled)) {
481 		/* Make sure cpu_phys_id is actually initialized */
482 		assert3u(os_atomic_load(&target_proc->cpu_flags, relaxed) & (InitState | StartedState),
483 		    ==, InitState | StartedState);
484 
485 		if (defer) {
486 #if defined(HAS_IPI)
487 			if (gFastIPI) {
488 				ml_cpu_signal_deferred(target_proc->cpu_phys_id);
489 			} else {
490 				PE_cpu_signal_deferred(getCpuDatap()->cpu_id, target_proc->cpu_id);
491 			}
492 #else
493 			PE_cpu_signal_deferred(getCpuDatap()->cpu_id, target_proc->cpu_id);
494 #endif /* defined(HAS_IPI) */
495 		} else {
496 #if defined(HAS_IPI)
497 			if (gFastIPI) {
498 				ml_cpu_signal(target_proc->cpu_phys_id);
499 			} else {
500 				PE_cpu_signal(getCpuDatap()->cpu_id, target_proc->cpu_id);
501 			}
502 #else
503 			PE_cpu_signal(getCpuDatap()->cpu_id, target_proc->cpu_id);
504 #endif /* defined(HAS_IPI) */
505 		}
506 	}
507 
508 	ml_set_interrupts_enabled(interruptible);
509 	return KERN_SUCCESS;
510 }
511 
512 kern_return_t
cpu_signal(cpu_data_t * target_proc,cpu_signal_t signal,void * p0,void * p1)513 cpu_signal(cpu_data_t *target_proc,
514     cpu_signal_t signal,
515     void *p0,
516     void *p1)
517 {
518 	return cpu_signal_internal(target_proc, signal, p0, p1, FALSE);
519 }
520 
521 kern_return_t
cpu_signal_deferred(cpu_data_t * target_proc,cpu_signal_t signal)522 cpu_signal_deferred(cpu_data_t *target_proc, cpu_signal_t signal)
523 {
524 	return cpu_signal_internal(target_proc, signal, NULL, NULL, TRUE);
525 }
526 
527 void
cpu_signal_cancel(cpu_data_t * target_proc,cpu_signal_t signal)528 cpu_signal_cancel(cpu_data_t *target_proc, cpu_signal_t signal)
529 {
530 	cpu_signal_t current_signals;
531 
532 	current_signals = os_atomic_andnot(&target_proc->cpu_signal, signal, acq_rel);
533 
534 
535 	if (!(current_signals & SIGPdisabled)) {
536 #if defined(HAS_IPI)
537 		if (gFastIPI) {
538 			ml_cpu_signal_retract(target_proc->cpu_phys_id);
539 		} else {
540 			PE_cpu_signal_cancel(getCpuDatap()->cpu_id, target_proc->cpu_id);
541 		}
542 #else
543 		PE_cpu_signal_cancel(getCpuDatap()->cpu_id, target_proc->cpu_id);
544 #endif /* defined(HAS_IPI) */
545 	}
546 }
547 
548 void
cpu_signal_handler(void)549 cpu_signal_handler(void)
550 {
551 	cpu_signal_handler_internal(FALSE);
552 }
553 
554 bool
cpu_has_SIGPdebug_pending(void)555 cpu_has_SIGPdebug_pending(void)
556 {
557 	cpu_data_t *cpu_data_ptr = getCpuDatap();
558 
559 	return cpu_data_ptr->cpu_signal & SIGPdebug;
560 }
561 
562 void
cpu_signal_handler_internal(boolean_t disable_signal)563 cpu_signal_handler_internal(boolean_t disable_signal)
564 {
565 	cpu_data_t     *cpu_data_ptr = getCpuDatap();
566 
567 	cpu_data_ptr->cpu_stat.ipi_cnt++;
568 	cpu_data_ptr->cpu_stat.ipi_cnt_wake++;
569 	SCHED_STATS_INC(ipi_count);
570 
571 	/*
572 	 * Employ an acquire barrier when loading cpu_signal to ensure that
573 	 * loads within individual signal handlers won't be speculated ahead
574 	 * of the load of cpu_signal.  This pairs with the release barrier
575 	 * in cpu_signal_internal() to ensure that once a flag has been set in
576 	 * the cpu_signal mask, any prerequisite setup is also visible to signal
577 	 * handlers.
578 	 */
579 	cpu_signal_t cpu_signal = os_atomic_or(&cpu_data_ptr->cpu_signal, 0, acquire);
580 
581 	if ((!(cpu_signal & SIGPdisabled)) && (disable_signal == TRUE)) {
582 		cpu_signal = os_atomic_or(&cpu_data_ptr->cpu_signal, SIGPdisabled, acq_rel);
583 	} else if ((cpu_signal & SIGPdisabled) && (disable_signal == FALSE)) {
584 		/* We must not clear SIGPdisabled unless the CPU is properly started */
585 		assert3u(os_atomic_load(&cpu_data_ptr->cpu_flags, relaxed) & (InitState | StartedState),
586 		    ==, InitState | StartedState);
587 		cpu_signal = os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPdisabled, acq_rel);
588 	}
589 
590 	while (cpu_signal & ~SIGPdisabled) {
591 		if (cpu_signal & SIGPdebug) {
592 			os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPdebug, acquire);
593 			INTERRUPT_MASKED_DEBUG_START(DebuggerXCall, DBG_INTR_TYPE_IPI);
594 			DebuggerXCall(cpu_data_ptr->cpu_int_state);
595 			INTERRUPT_MASKED_DEBUG_END();
596 		}
597 #if KPERF
598 		if (cpu_signal & SIGPkppet) {
599 			os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPkppet, acquire);
600 			extern void kperf_signal_handler(void);
601 			INTERRUPT_MASKED_DEBUG_START(kperf_signal_handler, DBG_INTR_TYPE_IPI);
602 			kperf_signal_handler();
603 			INTERRUPT_MASKED_DEBUG_END();
604 		}
605 #endif /* KPERF */
606 		if (cpu_signal & (SIGPxcall | SIGPxcallImm)) {
607 			cpu_handle_xcall(cpu_data_ptr);
608 		}
609 		if (cpu_signal & SIGPast) {
610 			os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPast, acquire);
611 			INTERRUPT_MASKED_DEBUG_START(ast_check, DBG_INTR_TYPE_IPI);
612 			ast_check(current_processor());
613 			INTERRUPT_MASKED_DEBUG_END();
614 		}
615 		if (cpu_signal & SIGPTimerLocal) {
616 			os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPTimerLocal, acquire);
617 			INTERRUPT_MASKED_DEBUG_START(timer_queue_expire_local, DBG_INTR_TYPE_IPI);
618 			timer_queue_expire_local(current_processor());
619 			INTERRUPT_MASKED_DEBUG_END();
620 		}
621 		if (cpu_signal & SIGPdeferred) {
622 			os_atomic_andnot(&cpu_data_ptr->cpu_signal, SIGPdeferred, acquire);
623 		}
624 
625 		cpu_signal = os_atomic_or(&cpu_data_ptr->cpu_signal, 0, acquire);
626 	}
627 }
628 
629 void
cpu_exit_wait(int cpu_id)630 cpu_exit_wait(int cpu_id)
631 {
632 #if !APPLEVIRTUALPLATFORM /* AVP doesn't provide an equivalent poll-for-powerdown operation */
633 #if USE_APPLEARMSMP
634 	if (!ml_is_quiescing()) {
635 		// For runtime disable (non S2R) the CPU will shut down immediately.
636 		ml_topology_cpu_t *cpu = &ml_get_topology_info()->cpus[cpu_id];
637 		assert(cpu && cpu->cpu_IMPL_regs);
638 		volatile uint64_t *cpu_sts = (void *)(cpu->cpu_IMPL_regs + CPU_PIO_CPU_STS_OFFSET);
639 
640 		// Poll the "CPU running state" field until it is 0 (off)
641 		// This loop typically finishes in about 600ns.  Sometimes it takes as long as 10us.
642 		// If it takes longer than 10s, assume something went horribly wrong and panic.
643 		uint64_t start = mach_absolute_time(), interval;
644 		nanoseconds_to_absolutetime(10 * NSEC_PER_SEC, &interval);
645 
646 		while ((*cpu_sts & CPU_PIO_CPU_STS_cpuRunSt_mask) != 0x00) {
647 			__builtin_arm_dsb(DSB_ISH);
648 			if (mach_absolute_time() > start + interval) {
649 #if NO_CPU_OVRD
650 				// On platforms where CPU_OVRD is unavailable, a core can get stuck
651 				// in a loop where it tries to enter WFI but is constantly woken up
652 				// by an IRQ or FIQ.  This condition persists until the cluster-wide
653 				// deep sleep bits are set.
654 				//
655 				// Making this a fatal condition would be a poor UX, but it's good to
656 				// print a warning so we know how often it happens.
657 				kprintf("CPU%d failed to shut down\n", cpu_id);
658 #else
659 				panic("CPU%d failed to shut down", cpu_id);
660 #endif
661 			}
662 		}
663 	}
664 #endif /* USE_APPLEARMSMP */
665 #endif /* !APPLEVIRTUALPLATFORM */
666 
667 	if (cpu_id != master_cpu || (support_bootcpu_shutdown && !ml_is_quiescing())) {
668 		// For S2R, ml_arm_sleep() will do some extra polling after setting ARM_CPU_ON_SLEEP_PATH.
669 		cpu_data_t      *cpu_data_ptr;
670 
671 		uint64_t start = mach_absolute_time(), interval;
672 		nanoseconds_to_absolutetime(10 * NSEC_PER_SEC, &interval);
673 
674 		cpu_data_ptr = CpuDataEntries[cpu_id].cpu_data_vaddr;
675 		while (!((*(volatile unsigned int*)&cpu_data_ptr->cpu_sleep_token) == ARM_CPU_ON_SLEEP_PATH)) {
676 			if (mach_absolute_time() > start + interval) {
677 				panic("CPU %d failed to reach ARM_CPU_ON_SLEEP_PATH: %d", cpu_id, cpu_data_ptr->cpu_sleep_token);
678 			}
679 		}
680 	}
681 }
682 
683 void
cpu_machine_init(void)684 cpu_machine_init(void)
685 {
686 	cpu_data_t *cpu_data_ptr = getCpuDatap();
687 
688 	if (cpu_data_ptr->cpu_cache_dispatch != NULL) {
689 		platform_cache_init();
690 	}
691 
692 	bool started = os_atomic_or_orig(&cpu_data_ptr->cpu_flags, StartedState, relaxed) & StartedState;
693 
694 	/* Note: this calls IOCPURunPlatformActiveActions when resuming on boot cpu */
695 	PE_cpu_machine_init(cpu_data_ptr->cpu_id, !started);
696 
697 	ml_init_interrupt();
698 }
699 
700 processor_t
current_processor(void)701 current_processor(void)
702 {
703 	return PERCPU_GET(processor);
704 }
705 
706 processor_t
cpu_to_processor(int cpu)707 cpu_to_processor(int cpu)
708 {
709 	cpu_data_t *cpu_data = cpu_datap(cpu);
710 	if (cpu_data != NULL) {
711 		return PERCPU_GET_RELATIVE(processor, cpu_data, cpu_data);
712 	} else {
713 		return NULL;
714 	}
715 }
716 
717 cpu_data_t *
processor_to_cpu_datap(processor_t processor)718 processor_to_cpu_datap(processor_t processor)
719 {
720 	assert(processor->cpu_id <= ml_get_max_cpu_number());
721 	assert(CpuDataEntries[processor->cpu_id].cpu_data_vaddr != NULL);
722 
723 	return PERCPU_GET_RELATIVE(cpu_data, processor, processor);
724 }
725 
726 __startup_func
727 static void
cpu_data_startup_init(void)728 cpu_data_startup_init(void)
729 {
730 	vm_size_t size = percpu_section_size() * (ml_get_cpu_count() - 1);
731 
732 	percpu_base.size = percpu_section_size();
733 	if (ml_get_cpu_count() == 1) {
734 		percpu_base.start = VM_MAX_KERNEL_ADDRESS;
735 		return;
736 	}
737 
738 	/*
739 	 * The memory needs to be physically contiguous because it contains
740 	 * cpu_data_t structures sometimes accessed during reset
741 	 * with the MMU off.
742 	 *
743 	 * kmem_alloc_contig() can't be used early, at the time STARTUP_SUB_PERCPU
744 	 * normally runs, so we instead steal the memory for the PERCPU subsystem
745 	 * even earlier.
746 	 */
747 	percpu_base.start  = (vm_offset_t)pmap_steal_memory(size, PAGE_SIZE);
748 	bzero((void *)percpu_base.start, size);
749 
750 	percpu_base.start -= percpu_section_start();
751 	percpu_base.end    = percpu_base.start + size - 1;
752 	percpu_base_cur    = percpu_base.start;
753 }
754 STARTUP(PMAP_STEAL, STARTUP_RANK_FIRST, cpu_data_startup_init);
755 
756 cpu_data_t *
cpu_data_alloc(boolean_t is_boot_cpu)757 cpu_data_alloc(boolean_t is_boot_cpu)
758 {
759 	cpu_data_t   *cpu_data_ptr = NULL;
760 	vm_address_t  base;
761 
762 	if (is_boot_cpu) {
763 		cpu_data_ptr = PERCPU_GET_MASTER(cpu_data);
764 	} else {
765 		base = os_atomic_add_orig(&percpu_base_cur,
766 		    percpu_section_size(), relaxed);
767 
768 		cpu_data_ptr = PERCPU_GET_WITH_BASE(base, cpu_data);
769 		cpu_stack_alloc(cpu_data_ptr);
770 	}
771 
772 	return cpu_data_ptr;
773 }
774 
775 ast_t *
ast_pending(void)776 ast_pending(void)
777 {
778 	return &getCpuDatap()->cpu_pending_ast;
779 }
780 
781 cpu_type_t
slot_type(int slot_num)782 slot_type(int slot_num)
783 {
784 	return cpu_datap(slot_num)->cpu_type;
785 }
786 
787 cpu_subtype_t
slot_subtype(int slot_num)788 slot_subtype(int slot_num)
789 {
790 	return cpu_datap(slot_num)->cpu_subtype;
791 }
792 
793 cpu_threadtype_t
slot_threadtype(int slot_num)794 slot_threadtype(int slot_num)
795 {
796 	return cpu_datap(slot_num)->cpu_threadtype;
797 }
798 
799 cpu_type_t
cpu_type(void)800 cpu_type(void)
801 {
802 	return getCpuDatap()->cpu_type;
803 }
804 
805 cpu_subtype_t
cpu_subtype(void)806 cpu_subtype(void)
807 {
808 	return getCpuDatap()->cpu_subtype;
809 }
810 
811 cpu_threadtype_t
cpu_threadtype(void)812 cpu_threadtype(void)
813 {
814 	return getCpuDatap()->cpu_threadtype;
815 }
816 
817 int
cpu_number(void)818 cpu_number(void)
819 {
820 	return current_thread()->machine.cpu_number;
821 }
822 
823 vm_offset_t
current_percpu_base(void)824 current_percpu_base(void)
825 {
826 	long base = current_thread()->machine.pcpu_data_base_and_cpu_number;
827 
828 	return (vm_offset_t)(base >> 16);
829 }
830 
831 vm_offset_t
other_percpu_base(int cpu)832 other_percpu_base(int cpu)
833 {
834 	return (vm_address_t)cpu_datap(cpu) - __PERCPU_ADDR(cpu_data);
835 }
836 
837 uint64_t
ml_get_wake_timebase(void)838 ml_get_wake_timebase(void)
839 {
840 	return wake_abstime;
841 }
842 
843 /*
844  * Called while running on a specific CPU to wait for it to handle the
845  * self-IPI that clears SIGPdisabled.
846  */
847 void
ml_wait_for_cpu_signal_to_enable(void)848 ml_wait_for_cpu_signal_to_enable(void)
849 {
850 	assert(ml_get_interrupts_enabled());
851 	cpu_data_t *cpu_data_ptr = getCpuDatap();
852 
853 	hw_wait_while_equals32(__DEVOLATILE(uint32_t*, &cpu_data_ptr->cpu_signal), SIGPdisabled);
854 }
855 
856 void
assert_ml_cpu_signal_is_enabled(bool enabled)857 assert_ml_cpu_signal_is_enabled(bool enabled)
858 {
859 	if (enabled) {
860 		assert((getCpuDatap()->cpu_signal & SIGPdisabled) == 0);
861 	} else {
862 		assert3u(getCpuDatap()->cpu_signal, ==, SIGPdisabled);
863 	}
864 }
865 
866 bool
ml_cpu_can_exit(__unused int cpu_id)867 ml_cpu_can_exit(__unused int cpu_id)
868 {
869 #if USE_APPLEARMSMP
870 	/*
871 	 * Cyprus and newer chips can disable individual non-boot CPUs. The
872 	 * implementation polls cpuX_IMPL_CPU_STS, which differs on older chips.
873 	 * Until the feature is known to be stable, guard it with a boot-arg.
874 	 */
875 
876 	bool cpu_supported = true;
877 
878 	if (cpu_id == master_cpu && !support_bootcpu_shutdown) {
879 		cpu_supported = false;
880 	}
881 
882 	if (enable_processor_exit) {
883 		return cpu_supported;
884 	}
885 
886 #if HAS_CLUSTER
887 	if (ml_get_topology_info()->cluster_power_down) {
888 		return cpu_supported;
889 	}
890 #endif /* HAS_CLUSTER */
891 
892 #endif /* USE_APPLEARMSMP */
893 
894 	return false;
895 }
896 
897 #ifdef USE_APPLEARMSMP
898 
899 void
ml_cpu_begin_state_transition(int cpu_id)900 ml_cpu_begin_state_transition(int cpu_id)
901 {
902 	lck_rw_lock_exclusive(&cpu_state_lock);
903 	CpuDataEntries[cpu_id].cpu_data_vaddr->in_state_transition = true;
904 	lck_rw_unlock_exclusive(&cpu_state_lock);
905 }
906 
907 void
ml_cpu_end_state_transition(int cpu_id)908 ml_cpu_end_state_transition(int cpu_id)
909 {
910 	lck_rw_lock_exclusive(&cpu_state_lock);
911 	CpuDataEntries[cpu_id].cpu_data_vaddr->in_state_transition = false;
912 	lck_rw_unlock_exclusive(&cpu_state_lock);
913 }
914 
915 void
ml_cpu_begin_loop(void)916 ml_cpu_begin_loop(void)
917 {
918 	lck_rw_lock_shared(&cpu_state_lock);
919 }
920 
921 void
ml_cpu_end_loop(void)922 ml_cpu_end_loop(void)
923 {
924 	lck_rw_unlock_shared(&cpu_state_lock);
925 }
926 
927 void
ml_cpu_power_enable(int cpu_id)928 ml_cpu_power_enable(int cpu_id)
929 {
930 	PE_cpu_power_enable(cpu_id);
931 }
932 
933 void
ml_cpu_power_disable(int cpu_id)934 ml_cpu_power_disable(int cpu_id)
935 {
936 	PE_cpu_power_disable(cpu_id);
937 }
938 
939 #else /* USE_APPLEARMSMP */
940 
941 void
ml_cpu_begin_state_transition(__unused int cpu_id)942 ml_cpu_begin_state_transition(__unused int cpu_id)
943 {
944 }
945 
946 void
ml_cpu_end_state_transition(__unused int cpu_id)947 ml_cpu_end_state_transition(__unused int cpu_id)
948 {
949 }
950 
951 void
ml_cpu_begin_loop(void)952 ml_cpu_begin_loop(void)
953 {
954 }
955 
956 void
ml_cpu_end_loop(void)957 ml_cpu_end_loop(void)
958 {
959 }
960 
961 void
ml_cpu_power_enable(__unused int cpu_id)962 ml_cpu_power_enable(__unused int cpu_id)
963 {
964 }
965 
966 void
ml_cpu_power_disable(__unused int cpu_id)967 ml_cpu_power_disable(__unused int cpu_id)
968 {
969 }
970 
971 #endif /* USE_APPLEARMSMP */
972