1 What: /sys/class/timecard/ 2 Date: September 2021 3 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 4 Description: This directory contains files and directories 5 providing a standardized interface to the ancillary 6 features of the OpenCompute timecard. 7 8 What: /sys/class/timecard/ocpN/ 9 Date: September 2021 10 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 11 Description: This directory contains the attributes of the Nth timecard 12 registered. 13 14 What: /sys/class/timecard/ocpN/available_clock_sources 15 Date: September 2021 16 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 17 Description: (RO) The list of available time sources that the PHC 18 uses for clock adjustments. 19 20 ==== ================================================= 21 NONE no adjustments 22 PPS adjustments come from the PPS1 selector (default) 23 TOD adjustments from the GNSS/TOD module 24 IRIG adjustments from external IRIG-B signal 25 DCF adjustments from external DCF signal 26 ==== ================================================= 27 28 What: /sys/class/timecard/ocpN/available_sma_inputs 29 Date: September 2021 30 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 31 Description: (RO) Set of available destinations (sinks) for a SMA 32 input signal. 33 34 ===== ================================================ 35 10Mhz signal is used as the 10Mhz reference clock 36 PPS1 signal is sent to the PPS1 selector 37 PPS2 signal is sent to the PPS2 selector 38 TS1 signal is sent to timestamper 1 39 TS2 signal is sent to timestamper 2 40 TS3 signal is sent to timestamper 3 41 TS4 signal is sent to timestamper 4 42 IRIG signal is sent to the IRIG-B module 43 DCF signal is sent to the DCF module 44 FREQ1 signal is sent to frequency counter 1 45 FREQ2 signal is sent to frequency counter 2 46 FREQ3 signal is sent to frequency counter 3 47 FREQ4 signal is sent to frequency counter 4 48 None signal input is disabled 49 ===== ================================================ 50 51 What: /sys/class/timecard/ocpN/available_sma_outputs 52 Date: May 2021 53 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 54 Description: (RO) Set of available sources for a SMA output signal. 55 56 ===== ================================================ 57 10Mhz output is from the 10Mhz reference clock 58 PHC output PPS is from the PHC clock 59 MAC output PPS is from the Miniature Atomic Clock 60 GNSS1 output PPS is from the first GNSS module 61 GNSS2 output PPS is from the second GNSS module 62 IRIG output is from the PHC, in IRIG-B format 63 DCF output is from the PHC, in DCF format 64 GEN1 output is from frequency generator 1 65 GEN2 output is from frequency generator 2 66 GEN3 output is from frequency generator 3 67 GEN4 output is from frequency generator 4 68 GND output is GND 69 VCC output is VCC 70 ===== ================================================ 71 72 What: /sys/class/timecard/ocpN/clock_source 73 Date: September 2021 74 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 75 Description: (RW) Contains the current synchronization source used by 76 the PHC. May be changed by writing one of the listed 77 values from the available_clock_sources attribute set. 78 79 What: /sys/class/timecard/ocpN/clock_status_drift 80 Date: March 2022 81 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 82 Description: (RO) Contains the current drift value used by the firmware 83 for internal disciplining of the atomic clock. 84 85 What: /sys/class/timecard/ocpN/clock_status_offset 86 Date: March 2022 87 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 88 Description: (RO) Contains the current offset value used by the firmware 89 for internal disciplining of the atomic clock. 90 91 What: /sys/class/timecard/ocpN/freqX 92 Date: March 2022 93 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 94 Description: (RO) Optional directory containing the sysfs nodes for 95 frequency counter <X>. 96 97 What: /sys/class/timecard/ocpN/freqX/frequency 98 Date: March 2022 99 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 100 Description: (RO) Contains the measured frequency over the specified 101 measurement period. 102 103 What: /sys/class/timecard/ocpN/freqX/seconds 104 Date: March 2022 105 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 106 Description: (RW) Specifies the number of seconds from 0-255 that the 107 frequency should be measured over. Write 0 to disable. 108 109 What: /sys/class/timecard/ocpN/genX 110 Date: March 2022 111 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 112 Description: (RO) Optional directory containing the sysfs nodes for 113 frequency generator <X>. 114 115 What: /sys/class/timecard/ocpN/genX/duty 116 Date: March 2022 117 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 118 Description: (RO) Specifies the signal duty cycle as a percentage from 1-99. 119 120 What: /sys/class/timecard/ocpN/genX/period 121 Date: March 2022 122 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 123 Description: (RO) Specifies the signal period in nanoseconds. 124 125 What: /sys/class/timecard/ocpN/genX/phase 126 Date: March 2022 127 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 128 Description: (RO) Specifies the signal phase offset in nanoseconds. 129 130 What: /sys/class/timecard/ocpN/genX/polarity 131 Date: March 2022 132 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 133 Description: (RO) Specifies the signal polarity, either 1 or 0. 134 135 What: /sys/class/timecard/ocpN/genX/running 136 Date: March 2022 137 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 138 Description: (RO) Either 0 or 1, showing if the signal generator is running. 139 140 What: /sys/class/timecard/ocpN/genX/start 141 Date: March 2022 142 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 143 Description: (RO) Shows the time in <sec>.<nsec> that the signal generator 144 started running. 145 146 What: /sys/class/timecard/ocpN/genX/signal 147 Date: March 2022 148 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 149 Description: (RW) Used to start the signal generator, and summarize 150 the current status. 151 152 The signal generator may be started by writing the signal 153 period, followed by the optional signal values. If the 154 optional values are not provided, they default to the current 155 settings, which may be obtained from the other sysfs nodes. 156 157 period [duty [phase [polarity]]] 158 159 echo 500000000 > signal # 1/2 second period 160 echo 1000000 40 100 > signal 161 echo 0 > signal # turn off generator 162 163 Period and phase are specified in nanoseconds. Duty cycle is 164 a percentage from 1-99. Polarity is 1 or 0. 165 166 Reading this node will return: 167 168 period duty phase polarity start_time 169 170 What: /sys/class/timecard/ocpN/gnss_sync 171 Date: September 2021 172 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 173 Description: (RO) Indicates whether a valid GNSS signal is received, 174 or when the signal was lost. 175 176 What: /sys/class/timecard/ocpN/i2c 177 Date: September 2021 178 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 179 Description: This optional attribute links to the associated i2c device. 180 181 What: /sys/class/timecard/ocpN/irig_b_mode 182 Date: September 2021 183 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 184 Description: (RW) An integer from 0-7 indicating the timecode format 185 of the IRIG-B output signal: B00<n> 186 187 What: /sys/class/timecard/ocpN/pps 188 Date: September 2021 189 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 190 Description: This optional attribute links to the associated PPS device. 191 192 What: /sys/class/timecard/ocpN/ptp 193 Date: September 2021 194 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 195 Description: This attribute links to the associated PTP device. 196 197 What: /sys/class/timecard/ocpN/serialnum 198 Date: September 2021 199 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 200 Description: (RO) Provides the serial number of the timecard. 201 202 What: /sys/class/timecard/ocpN/sma1 203 What: /sys/class/timecard/ocpN/sma2 204 What: /sys/class/timecard/ocpN/sma3 205 What: /sys/class/timecard/ocpN/sma4 206 Date: September 2021 207 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 208 Description: (RW) These attributes specify the direction of the signal 209 on the associated SMA connectors, and also the signal sink 210 or source. 211 212 The display format of the attribute is a space separated 213 list of signals, prefixed by the input/output direction. 214 215 The signal direction may be changed (if supported) by 216 prefixing the signal list with either "in:" or "out:". 217 If neither prefix is present, then the direction is unchanged. 218 219 The output signal may be changed by writing one of the listed 220 values from the available_sma_outputs attribute set. 221 222 The input destinations may be changed by writing multiple 223 values from the available_sma_inputs attribute set, 224 separated by spaces. If there are duplicated input 225 destinations between connectors, the lowest numbered SMA 226 connector is given priority. 227 228 Note that not all input combinations may make sense. 229 230 The 10Mhz reference clock input is currently only valid 231 on SMA1 and may not be combined with other destination sinks. 232 233 What: /sys/class/timecard/ocpN/tod_correction 234 Date: March 2022 235 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 236 Description: (RW) The incoming GNSS signal is in UTC time, and the NMEA 237 format messages do not provide a TAI offset. This sets the 238 correction value for the incoming time. 239 240 If UBX_LS is enabled, this should be 0, and the offset is 241 taken from the UBX-NAV-TIMELS message. 242 243 What: /sys/class/timecard/ocpN/ts_window_adjust 244 Date: September 2021 245 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 246 Description: (RW) When retrieving the PHC with the PTP SYS_OFFSET_EXTENDED 247 ioctl, a system timestamp is made before and after the PHC 248 time is retrieved. The midpoint between the two system 249 timestamps is usually taken to be the SYS time associated 250 with the PHC time. This estimate may be wrong, as it depends 251 on PCI latencies, and when the PHC time was latched 252 253 The attribute value reduces the end timestamp by the given 254 number of nanoseconds, so the computed midpoint matches the 255 retrieved PHC time. 256 257 The initial value is set based on measured PCI latency and 258 the estimated point where the FPGA latches the PHC time. This 259 value may be changed by writing an unsigned integer. 260 261 What: /sys/class/timecard/ocpN/tty 262 Date: August 2024 263 Contact: Vadim Fedorenko <vadim.fedorenko@linux.dev> 264 Description: (RO) Directory containing the sysfs nodes for TTY attributes 265 266 What: /sys/class/timecard/ocpN/tty/ttyGNSS 267 What: /sys/class/timecard/ocpN/tty/ttyGNSS2 268 Date: August 2024 269 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 270 Description: (RO) These optional attributes contain names of the TTY serial 271 ports associated with the GNSS devices. 272 273 What: /sys/class/timecard/ocpN/tty/ttyMAC 274 Date: August 2024 275 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 276 Description: (RO) This optional attribute contains name of the TTY serial 277 port associated with the Miniature Atomic Clock. 278 279 What: /sys/class/timecard/ocpN/tty/ttyNMEA 280 Date: August 2024 281 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 282 Description: (RO) This optional attribute contains name of the TTY serial 283 port which outputs the PHC time in NMEA ZDA format. 284 285 What: /sys/class/timecard/ocpN/utc_tai_offset 286 Date: September 2021 287 Contact: Jonathan Lemon <jonathan.lemon@gmail.com> 288 Description: (RW) The DCF and IRIG output signals are in UTC, while the 289 TimeCard operates on TAI. This attribute allows setting the 290 offset in seconds, which is added to the TAI timebase for 291 these formats. 292 293 The offset may be changed by writing an unsigned integer.
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