projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| 0a7de745 A |
1 | /* |
| 2 | * Copyright (c) 2017 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, | |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 23 | * Please see the License for the specific language governing rights and | |
| 24 | * limitations under the License. | |
| 25 | * | |
| 26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ | |
| 27 | */ | |
| 28 | #include <kern/misc_protos.h> | |
| 29 | #include <x86_64/machine_remote_time.h> | |
| cb323159 | 30 | #include <machine/atomic.h> |
| 0a7de745 A |
31 | #include <kern/locks.h> |
| 32 | #include <kern/clock.h> | |
| 33 | ||
| 34 | void mach_bridge_send_timestamp(uint64_t timestamp); | |
| 35 | ||
| 36 | extern _Atomic uint32_t bt_init_flag; | |
| 37 | extern lck_spin_t *bt_maintenance_lock; | |
| 38 | extern void mach_bridge_timer_init(void); | |
| 39 | extern uint32_t bt_enable_flag; | |
| 40 | ||
| 41 | /* | |
| 42 | * Delay sending timestamps by certain interval to | |
| 43 | * avoid overwriting sentinel values | |
| 44 | */ | |
| 45 | #define DELAY_INTERVAL_NS (50 * NSEC_PER_MSEC) | |
| 46 | static uint64_t bt_delay_timestamp = 0; | |
| 47 | static mach_bridge_regwrite_timestamp_func_t bridge_regwrite_timestamp_callback = NULL; | |
| 48 | ||
| 49 | /* | |
| 50 | * This function should only be called by the kext | |
| 51 | * responsible for sending timestamps across the link | |
| 52 | */ | |
| 53 | void | |
| 54 | mach_bridge_register_regwrite_timestamp_callback(mach_bridge_regwrite_timestamp_func_t func) | |
| 55 | { | |
| 56 | static uint64_t delay_amount = 0; | |
| 57 | ||
| cb323159 | 58 | if (!os_atomic_load(&bt_init_flag, relaxed)) { |
| 0a7de745 A |
59 | mach_bridge_timer_init(); |
| 60 | nanoseconds_to_absolutetime(DELAY_INTERVAL_NS, &delay_amount); | |
| cb323159 | 61 | os_atomic_store(&bt_init_flag, 1, release); |
| 0a7de745 A |
62 | } |
| 63 | ||
| 64 | lck_spin_lock(bt_maintenance_lock); | |
| 65 | bridge_regwrite_timestamp_callback = func; | |
| 66 | bt_enable_flag = (func != NULL) ? 1 : 0; | |
| 67 | bt_delay_timestamp = mach_absolute_time() + delay_amount; | |
| 68 | lck_spin_unlock(bt_maintenance_lock); | |
| 69 | } | |
| 70 | ||
| 71 | void | |
| 72 | mach_bridge_send_timestamp(uint64_t timestamp) | |
| 73 | { | |
| 74 | LCK_SPIN_ASSERT(bt_maintenance_lock, LCK_ASSERT_OWNED); | |
| 75 | ||
| 76 | if (bt_delay_timestamp > 0) { | |
| 77 | uint64_t now = mach_absolute_time(); | |
| 78 | if (now < bt_delay_timestamp) { | |
| 79 | return; | |
| 80 | } | |
| 81 | bt_delay_timestamp = 0; | |
| 82 | } | |
| 83 | ||
| 84 | if (bridge_regwrite_timestamp_callback) { | |
| 85 | bridge_regwrite_timestamp_callback(timestamp); | |
| 86 | } | |
| 87 | } |