xref: /qemu/target/s390x/tcg/s390-tod.h (revision c9274b6bf0571ecbaaed3e9c3b229e17607a0ea2)
1*4037c39bSRichard Henderson /*
2*4037c39bSRichard Henderson  * TOD (Time Of Day) clock
3*4037c39bSRichard Henderson  *
4*4037c39bSRichard Henderson  * Copyright 2018 Red Hat, Inc.
5*4037c39bSRichard Henderson  * Author(s): David Hildenbrand <david@redhat.com>
6*4037c39bSRichard Henderson  *
7*4037c39bSRichard Henderson  * This work is licensed under the terms of the GNU GPL, version 2 or later.
8*4037c39bSRichard Henderson  * See the COPYING file in the top-level directory.
9*4037c39bSRichard Henderson  */
10*4037c39bSRichard Henderson 
11*4037c39bSRichard Henderson #ifndef TARGET_S390_TOD_H
12*4037c39bSRichard Henderson #define TARGET_S390_TOD_H
13*4037c39bSRichard Henderson 
14*4037c39bSRichard Henderson /* The value of the TOD clock for 1.1.1970. */
15*4037c39bSRichard Henderson #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
16*4037c39bSRichard Henderson 
17*4037c39bSRichard Henderson /* Converts ns to s390's clock format */
time2tod(uint64_t ns)18*4037c39bSRichard Henderson static inline uint64_t time2tod(uint64_t ns)
19*4037c39bSRichard Henderson {
20*4037c39bSRichard Henderson     return (ns << 9) / 125 + (((ns & 0xff80000000000000ull) / 125) << 9);
21*4037c39bSRichard Henderson }
22*4037c39bSRichard Henderson 
23*4037c39bSRichard Henderson /* Converts s390's clock format to ns */
tod2time(uint64_t t)24*4037c39bSRichard Henderson static inline uint64_t tod2time(uint64_t t)
25*4037c39bSRichard Henderson {
26*4037c39bSRichard Henderson     return ((t >> 9) * 125) + (((t & 0x1ff) * 125) >> 9);
27*4037c39bSRichard Henderson }
28*4037c39bSRichard Henderson 
29*4037c39bSRichard Henderson #endif
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