drivers/ptp/ptp_s390.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * s390 PTP clock driver
   4  *
   5  */
   6
   7 #include "ptp_private.h"
   8 #include <linux/time.h>
   9 #include <asm/stp.h>
  10
  11 static struct ptp_clock *ptp_stcke_clock, *ptp_qpt_clock;
  12
  13 static int ptp_s390_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
  14 {
  15         return -EOPNOTSUPP;
  16 }
  17
  18 static int ptp_s390_adjtime(struct ptp_clock_info *ptp, s64 delta)
  19 {
  20         return -EOPNOTSUPP;
  21 }
  22
  23 static struct timespec64 eitod_to_timespec64(union tod_clock *clk)
  24 {
  25         return ns_to_timespec64(eitod_to_ns(clk->eitod - TOD_UNIX_EPOCH));
  26 }
  27
  28 static struct timespec64 tod_to_timespec64(unsigned long tod)
  29 {
  30         return ns_to_timespec64(tod_to_ns(tod - TOD_UNIX_EPOCH));
  31 }
  32
  33 static int ptp_s390_stcke_gettime(struct ptp_clock_info *ptp,
  34                                   struct timespec64 *ts)
  35 {
  36         union tod_clock tod;
  37
  38         if (!stp_enabled())
  39                 return -EOPNOTSUPP;
  40
  41         store_tod_clock_ext(&tod);
  42         *ts = eitod_to_timespec64(&tod);
  43         return 0;
  44 }
  45
  46 static int ptp_s390_qpt_gettime(struct ptp_clock_info *ptp,
  47                                 struct timespec64 *ts)
  48 {
  49         unsigned long tod;
  50
  51         ptff(&tod, sizeof(tod), PTFF_QPT);
  52         *ts = tod_to_timespec64(tod);
  53         return 0;
  54 }
  55
  56 static int ptp_s390_settime(struct ptp_clock_info *ptp,
  57                             const struct timespec64 *ts)
  58 {
  59         return -EOPNOTSUPP;
  60 }
  61
  62 static int s390_arch_ptp_get_crosststamp(ktime_t *device_time,
  63                                          struct system_counterval_t *system_counter,
  64                                          void *ctx)
  65 {
  66         union tod_clock clk;
  67
  68         store_tod_clock_ext(&clk);
  69         *device_time = ns_to_ktime(tod_to_ns(clk.tod - TOD_UNIX_EPOCH));
  70         system_counter->cycles = clk.tod;
  71         system_counter->cs_id = CSID_S390_TOD;
  72         return 0;
  73 }
  74
  75 static int ptp_s390_getcrosststamp(struct ptp_clock_info *ptp,
  76                                    struct system_device_crosststamp *xtstamp)
  77 {
  78         if (!stp_enabled())
  79                 return -EOPNOTSUPP;
  80         return get_device_system_crosststamp(s390_arch_ptp_get_crosststamp, NULL, NULL, xtstamp);
  81 }
  82
  83 static struct ptp_clock_info ptp_s390_stcke_info = {
  84         .owner          = THIS_MODULE,
  85         .name           = "s390 STCKE Clock",
  86         .max_adj        = 0,
  87         .adjfine        = ptp_s390_adjfine,
  88         .adjtime        = ptp_s390_adjtime,
  89         .gettime64      = ptp_s390_stcke_gettime,
  90         .settime64      = ptp_s390_settime,
  91         .getcrosststamp = ptp_s390_getcrosststamp,
  92 };
  93
  94 static struct ptp_clock_info ptp_s390_qpt_info = {
  95         .owner          = THIS_MODULE,
  96         .name           = "s390 Physical Clock",
  97         .max_adj        = 0,
  98         .adjfine        = ptp_s390_adjfine,
  99         .adjtime        = ptp_s390_adjtime,
 100         .gettime64      = ptp_s390_qpt_gettime,
 101         .settime64      = ptp_s390_settime,
 102 };
 103
 104 static __init int ptp_s390_init(void)
 105 {
 106         ptp_stcke_clock = ptp_clock_register(&ptp_s390_stcke_info, NULL);
 107         if (IS_ERR(ptp_stcke_clock))
 108                 return PTR_ERR(ptp_stcke_clock);
 109
 110         ptp_qpt_clock = ptp_clock_register(&ptp_s390_qpt_info, NULL);
 111         if (IS_ERR(ptp_qpt_clock)) {
 112                 ptp_clock_unregister(ptp_stcke_clock);
 113                 return PTR_ERR(ptp_qpt_clock);
 114         }
 115         return 0;
 116 }
 117
 118 static __exit void ptp_s390_exit(void)
 119 {
 120         ptp_clock_unregister(ptp_qpt_clock);
 121         ptp_clock_unregister(ptp_stcke_clock);
 122 }
 123
 124 module_init(ptp_s390_init);
 125 module_exit(ptp_s390_exit);
 126
 127 MODULE_AUTHOR("Sven Schnelle <svens@linux.ibm.com>");
 128 MODULE_DESCRIPTION("s390 Physical/STCKE Clock PtP Driver");
 129 MODULE_LICENSE("GPL");