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 <machine/atomic.h>
30 #include <mach/mach_time.h>
31 #include <mach/clock_types.h>
32 #include <kern/clock.h>
33 #include <kern/locks.h>
34 #include <arm64/machine_remote_time.h>
35 #include <sys/kdebug.h>
36 #include <arm/machine_routines.h>
37 #include <kern/remote_time.h>
38
39 _Atomic uint32_t bt_init_flag = 0;
40
41 extern void mach_bridge_add_timestamp(uint64_t remote_timestamp, uint64_t local_timestamp);
42 extern void bt_calibration_thread_start(void);
43 extern void bt_params_add(struct bt_params *params);
44
45 void
mach_bridge_init_timestamp(void)46 mach_bridge_init_timestamp(void)
47 {
48 /* This function should be called only once by the driver
49 * implementing the interrupt handler for receiving timestamps */
50 if (os_atomic_load(&bt_init_flag, relaxed)) {
51 return;
52 }
53
54 os_atomic_store(&bt_init_flag, 1, release);
55
56 /* Start the kernel thread only after all the locks have been initialized */
57 bt_calibration_thread_start();
58 }
59
60 /*
61 * Conditions: Should be called from primary interrupt context
62 */
63 void
mach_bridge_recv_timestamps(uint64_t remoteTimestamp,uint64_t localTimestamp)64 mach_bridge_recv_timestamps(uint64_t remoteTimestamp, uint64_t localTimestamp)
65 {
66 assert(ml_at_interrupt_context() == TRUE);
67
68 /* Ensure the locks have been initialized */
69 if (!os_atomic_load(&bt_init_flag, acquire)) {
70 panic("%s called before mach_bridge_init_timestamp", __func__);
71 return;
72 }
73
74 KDBG(MACHDBG_CODE(DBG_MACH_CLOCK, MACH_BRIDGE_RCV_TS), localTimestamp, remoteTimestamp);
75
76 lck_spin_lock(&bt_spin_lock);
77 mach_bridge_add_timestamp(remoteTimestamp, localTimestamp);
78 lck_spin_unlock(&bt_spin_lock);
79
80 return;
81 }
82
83 /*
84 * This function is used to set parameters, calculated externally,
85 * needed for mach_bridge_remote_time.
86 */
87 void
mach_bridge_set_params(uint64_t local_timestamp,uint64_t remote_timestamp,double rate)88 mach_bridge_set_params(uint64_t local_timestamp, uint64_t remote_timestamp, double rate)
89 {
90 /* Ensure the locks have been initialized */
91 if (!os_atomic_load(&bt_init_flag, acquire)) {
92 panic("%s called before mach_bridge_init_timestamp", __func__);
93 return;
94 }
95
96 struct bt_params params = {};
97 params.base_local_ts = local_timestamp;
98 params.base_remote_ts = remote_timestamp;
99 params.rate = rate;
100 lck_spin_lock(&bt_ts_conversion_lock);
101 bt_params_add(¶ms);
102 lck_spin_unlock(&bt_ts_conversion_lock);
103 KDBG(MACHDBG_CODE(DBG_MACH_CLOCK, MACH_BRIDGE_TS_PARAMS), params.base_local_ts,
104 params.base_remote_ts, *(uint64_t *)((void *)¶ms.rate));
105 }
106