What: /sys/class/timecard/ Date: September 2021 Contact: Jonathan Lemon Description: This directory contains files and directories providing a standardized interface to the ancillary features of the OpenCompute timecard. What: /sys/class/timecard/ocpN/ Date: September 2021 Contact: Jonathan Lemon Description: This directory contains the attributes of the Nth timecard registered. What: /sys/class/timecard/ocpN/available_clock_sources Date: September 2021 Contact: Jonathan Lemon Description: (RO) The list of available time sources that the PHC uses for clock adjustments. ==== ================================================= NONE no adjustments PPS adjustments come from the PPS1 selector (default) TOD adjustments from the GNSS/TOD module IRIG adjustments from external IRIG-B signal DCF adjustments from external DCF signal ==== ================================================= What: /sys/class/timecard/ocpN/available_sma_inputs Date: September 2021 Contact: Jonathan Lemon Description: (RO) Set of available destinations (sinks) for a SMA input signal. ===== ================================================ 10Mhz signal is used as the 10Mhz reference clock PPS1 signal is sent to the PPS1 selector PPS2 signal is sent to the PPS2 selector TS1 signal is sent to timestamper 1 TS2 signal is sent to timestamper 2 IRIG signal is sent to the IRIG-B module DCF signal is sent to the DCF module ===== ================================================ What: /sys/class/timecard/ocpN/available_sma_outputs Date: May 2021 Contact: Jonathan Lemon Description: (RO) Set of available sources for a SMA output signal. ===== ================================================ 10Mhz output is from the 10Mhz reference clock PHC output PPS is from the PHC clock MAC output PPS is from the Miniature Atomic Clock GNSS output PPS is from the GNSS module GNSS2 output PPS is from the second GNSS module IRIG output is from the PHC, in IRIG-B format DCF output is from the PHC, in DCF format ===== ================================================ What: /sys/class/timecard/ocpN/clock_source Date: September 2021 Contact: Jonathan Lemon Description: (RW) Contains the current synchronization source used by the PHC. May be changed by writing one of the listed values from the available_clock_sources attribute set. What: /sys/class/timecard/ocpN/gnss_sync Date: September 2021 Contact: Jonathan Lemon Description: (RO) Indicates whether a valid GNSS signal is received, or when the signal was lost. What: /sys/class/timecard/ocpN/i2c Date: September 2021 Contact: Jonathan Lemon Description: This optional attribute links to the associated i2c device. What: /sys/class/timecard/ocpN/irig_b_mode Date: September 2021 Contact: Jonathan Lemon Description: (RW) An integer from 0-7 indicating the timecode format of the IRIG-B output signal: B00 What: /sys/class/timecard/ocpN/pps Date: September 2021 Contact: Jonathan Lemon Description: This optional attribute links to the associated PPS device. What: /sys/class/timecard/ocpN/ptp Date: September 2021 Contact: Jonathan Lemon Description: This attribute links to the associated PTP device. What: /sys/class/timecard/ocpN/serialnum Date: September 2021 Contact: Jonathan Lemon Description: (RO) Provides the serial number of the timecard. What: /sys/class/timecard/ocpN/sma1 What: /sys/class/timecard/ocpN/sma2 What: /sys/class/timecard/ocpN/sma3 What: /sys/class/timecard/ocpN/sma4 Date: September 2021 Contact: Jonathan Lemon Description: (RW) These attributes specify the direction of the signal on the associated SMA connectors, and also the signal sink or source. The display format of the attribute is a space separated list of signals, prefixed by the input/output direction. The signal direction may be changed (if supported) by prefixing the signal list with either "in:" or "out:". If neither prefix is present, then the direction is unchanged. The output signal may be changed by writing one of the listed values from the available_sma_outputs attribute set. The input destinations may be changed by writing multiple values from the available_sma_inputs attribute set, separated by spaces. If there are duplicated input destinations between connectors, the lowest numbered SMA connector is given priority. Note that not all input combinations may make sense. The 10Mhz reference clock input is currently only valid on SMA1 and may not be combined with other destination sinks. What: /sys/class/timecard/ocpN/ts_window_adjust Date: September 2021 Contact: Jonathan Lemon Description: (RW) When retrieving the PHC with the PTP SYS_OFFSET_EXTENDED ioctl, a system timestamp is made before and after the PHC time is retrieved. The midpoint between the two system timestamps is usually taken to be the SYS time associated with the PHC time. This estimate may be wrong, as it depends on PCI latencies, and when the PHC time was latched The attribute value reduces the end timestamp by the given number of nanoseconds, so the computed midpoint matches the retrieved PHC time. The initial value is set based on measured PCI latency and the estimated point where the FPGA latches the PHC time. This value may be changed by writing an unsigned integer. What: /sys/class/timecard/ocpN/ttyGNSS What: /sys/class/timecard/ocpN/ttyGNSS2 Date: September 2021 Contact: Jonathan Lemon Description: These optional attributes link to the TTY serial ports associated with the GNSS devices. What: /sys/class/timecard/ocpN/ttyMAC Date: September 2021 Contact: Jonathan Lemon Description: This optional attribute links to the TTY serial port associated with the Miniature Atomic Clock. What: /sys/class/timecard/ocpN/ttyNMEA Date: September 2021 Contact: Jonathan Lemon Description: This optional attribute links to the TTY serial port which outputs the PHC time in NMEA ZDA format. What: /sys/class/timecard/ocpN/utc_tai_offset Date: September 2021 Contact: Jonathan Lemon Description: (RW) The DCF and IRIG output signals are in UTC, while the TimeCard operates on TAI. This attribute allows setting the offset in seconds, which is added to the TAI timebase for these formats. The offset may be changed by writing an unsigned integer.