$ ip link set can0 type can help
Usage: ip link set DEVICE type can
- [ bitrate BITRATE [ sample-point SAMPLE-POINT] ] |
- [ tq TQ prop-seg PROP_SEG phase-seg1 PHASE-SEG1
- phase-seg2 PHASE-SEG2 [ sjw SJW ] ]
-
- [ loopback { on | off } ]
- [ listen-only { on | off } ]
- [ triple-sampling { on | off } ]
-
- [ restart-ms TIME-MS ]
- [ restart ]
-
- Where: BITRATE := { 1..1000000 }
- SAMPLE-POINT := { 0.000..0.999 }
- TQ := { NUMBER }
- PROP-SEG := { 1..8 }
- PHASE-SEG1 := { 1..8 }
- PHASE-SEG2 := { 1..8 }
- SJW := { 1..4 }
- RESTART-MS := { 0 | NUMBER }
+ [ bitrate BITRATE [ sample-point SAMPLE-POINT] ] |
+ [ tq TQ prop-seg PROP_SEG phase-seg1 PHASE-SEG1
+ phase-seg2 PHASE-SEG2 [ sjw SJW ] ]
+
+ [ dbitrate BITRATE [ dsample-point SAMPLE-POINT] ] |
+ [ dtq TQ dprop-seg PROP_SEG dphase-seg1 PHASE-SEG1
+ dphase-seg2 PHASE-SEG2 [ dsjw SJW ] ]
+
+ [ loopback { on | off } ]
+ [ listen-only { on | off } ]
+ [ triple-sampling { on | off } ]
+ [ one-shot { on | off } ]
+ [ berr-reporting { on | off } ]
+ [ fd { on | off } ]
+ [ fd-non-iso { on | off } ]
+ [ presume-ack { on | off } ]
+
+ [ restart-ms TIME-MS ]
+ [ restart ]
+
+ Where: BITRATE := { 1..1000000 }
+ SAMPLE-POINT := { 0.000..0.999 }
+ TQ := { NUMBER }
+ PROP-SEG := { 1..8 }
+ PHASE-SEG1 := { 1..8 }
+ PHASE-SEG2 := { 1..8 }
+ SJW := { 1..4 }
+ RESTART-MS := { 0 | NUMBER }
- Display CAN device details and statistics:
The CAN device MTU can be retrieved e.g. with a SIOCGIFMTU ioctl() syscall.
N.B. CAN FD capable devices can also handle and send legacy CAN frames.
- FIXME: Add details about the CAN FD controller configuration when available.
+ When configuring CAN FD capable CAN controllers an additional 'data' bitrate
+ has to be set. This bitrate for the data phase of the CAN FD frame has to be
+ at least the bitrate which was configured for the arbitration phase. This
+ second bitrate is specified analogue to the first bitrate but the bitrate
+ setting keywords for the 'data' bitrate start with 'd' e.g. dbitrate,
+ dsample-point, dsjw or dtq and similar settings. When a data bitrate is set
+ within the configuration process the controller option "fd on" can be
+ specified to enable the CAN FD mode in the CAN controller. This controller
+ option also switches the device MTU to 72 (CANFD_MTU).
+
+ The first CAN FD specification presented as whitepaper at the International
+ CAN Conference 2012 needed to be improved for data integrity reasons.
+ Therefore two CAN FD implementations have to be distinguished today:
+
+ - ISO compliant: The ISO 11898-1:2015 CAN FD implementation (default)
+ - non-ISO compliant: The CAN FD implementation following the 2012 whitepaper
+
+ Finally there are three types of CAN FD controllers:
+
+ 1. ISO compliant (fixed)
+ 2. non-ISO compliant (fixed, like the M_CAN IP core v3.0.1 in m_can.c)
+ 3. ISO/non-ISO CAN FD controllers (switchable, like the PEAK PCAN-USB FD)
+
+ The current ISO/non-ISO mode is announced by the CAN controller driver via
+ netlink and displayed by the 'ip' tool (controller option FD-NON-ISO).
+ The ISO/non-ISO-mode can be altered by setting 'fd-non-iso {on|off}' for
+ switchable CAN FD controllers only.
+
+ Example configuring 500 kbit/s arbitration bitrate and 4 Mbit/s data bitrate:
+
+ $ ip link set can0 up type can bitrate 500000 sample-point 0.75 \
+ dbitrate 4000000 dsample-point 0.8 fd on
+ $ ip -details link show can0
+ 5: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 72 qdisc pfifo_fast state UNKNOWN \
+ mode DEFAULT group default qlen 10
+ link/can promiscuity 0
+ can <FD> state ERROR-ACTIVE (berr-counter tx 0 rx 0) restart-ms 0
+ bitrate 500000 sample-point 0.750
+ tq 50 prop-seg 14 phase-seg1 15 phase-seg2 10 sjw 1
+ pcan_usb_pro_fd: tseg1 1..64 tseg2 1..16 sjw 1..16 brp 1..1024 \
+ brp-inc 1
+ dbitrate 4000000 dsample-point 0.800
+ dtq 12 dprop-seg 7 dphase-seg1 8 dphase-seg2 4 dsjw 1
+ pcan_usb_pro_fd: dtseg1 1..16 dtseg2 1..8 dsjw 1..4 dbrp 1..1024 \
+ dbrp-inc 1
+ clock 80000000
+
+ Example when 'fd-non-iso on' is added on this switchable CAN FD adapter:
+ can <FD,FD-NON-ISO> state ERROR-ACTIVE (berr-counter tx 0 rx 0) restart-ms 0
6.7 Supported CAN hardware
projects / karo-tx-linux.git / blobdiff