xref: /qemu/target/s390x/tcg/s390-tod.h (revision 9b89cdb2a5064a87b8a7172fa1748d46aa37a9df)
1  /*
2   * TOD (Time Of Day) clock
3   *
4   * Copyright 2018 Red Hat, Inc.
5   * Author(s): David Hildenbrand <david@redhat.com>
6   *
7   * This work is licensed under the terms of the GNU GPL, version 2 or later.
8   * See the COPYING file in the top-level directory.
9   */
10  
11  #ifndef TARGET_S390_TOD_H
12  #define TARGET_S390_TOD_H
13  
14  /* The value of the TOD clock for 1.1.1970. */
15  #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
16  
17  /* Converts ns to s390's clock format */
18  static inline uint64_t time2tod(uint64_t ns)
19  {
20      return (ns << 9) / 125 + (((ns & 0xff80000000000000ull) / 125) << 9);
21  }
22  
23  /* Converts s390's clock format to ns */
24  static inline uint64_t tod2time(uint64_t t)
25  {
26      return ((t >> 9) * 125) + (((t & 0x1ff) * 125) >> 9);
27  }
28  
29  #endif
30