The Secondary Sample Point Source field has been
set to an incorrect value by some mistake in the
past
0b01 - SSP_SRC_NO_SSP - SSP is not used.
for data bitrates above 1 MBit/s. The correct/default
value already used for lower bitrates is
0b00 - SSP_SRC_MEAS_N_OFFSET - SSP position = TRV_DELAY
(Measured Transmitter delay) + SSP_OFFSET.
The related configuration register structure is described
in section 3.1.46 SSP_CFG of the CTU CAN FD
IP CORE Datasheet.
The analysis leading to the proper configuration
is described in section 2.8.3 Secondary sampling point
of the datasheet.
The change has been tested on AMD/Xilinx Zynq
with the next CTU CN FD IP core versions:
- 2.6 aka master in the "integration with Zynq-7000 system" test
6.12.43-rt12+ #1 SMP PREEMPT_RT kernel with CTU CAN FD git
driver (change already included in the driver repo)
- older 2.5 snapshot with mainline kernels with this patch
applied locally in the multiple CAN latency tester nightly runs
6.18.0-rc4-rt3-dut #1 SMP PREEMPT_RT
6.19.0-rc3-dut
The logs, the datasheet and sources are available at
https://canbus.pages.fel.cvut.cz/
Signed-off-by: Ondrej Ille <ondrej.ille@gmail.com>
Signed-off-by: Pavel Pisa <pisa@fel.cvut.cz>
Link: https://patch.msgid.link/20260105111620.16580-1-pisa@fel.cvut.cz
Fixes: 2dcb8e8782 ("can: ctucanfd: add support for CTU CAN FD open-source IP core - bus independent part.")
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can_change_mtu() became obsolete by commit 2304993860 ("can: populate the
minimum and maximum MTU values"). Now that net_device->min_mtu and
net_device->max_mtu are populated, all the checks are already done by
dev_validate_mtu() in net/core/dev.c.
Remove the net_device_ops->ndo_change_mtu() callback of all the physical
interfaces, then remove can_change_mtu(). Only keep the vcan_change_mtu()
and vxcan_change_mtu() because the virtual interfaces use their own
different MTU logic.
The only functional change this patch introduces is that now the user will
be able to change the MTU even if the interface is up. This does not matter
for Classical CAN and CAN FD because their MTU range is composed of only
one value, respectively CAN_MTU and CANFD_MTU. For the upcoming CAN XL, the
MTU will be configurable within the CANXL_MIN_MTU to CANXL_MAX_MTU range at
any time, even if the interface is up. This is consistent with the other
net protocols and does not contradict ISO 11898-1:2024 as having a
modifiable MTU is a kernel extension.
Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/20251003-remove-can_change_mtu-v1-1-337f8bc21181@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This is a preparation patch for the introduction of CAN XL.
CAN FD and CAN XL uses similar bittiming parameters. Add one level of
nesting for all the CAN FD parameters. Typically:
priv->can.data_bittiming;
becomes:
priv->can.fd.data_bittiming;
This way, the CAN XL equivalent (to be introduced later) would be:
priv->can.xl.data_bittiming;
Add the new struct data_bittiming_params which contains all the data
bittiming parameters, including the TDC and the callback functions.
This done, update all the CAN FD drivers to make use of the new
layout.
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://patch.msgid.link/20250501171213.2161572-2-mailhol.vincent@wanadoo.fr
[mkl: fix rcar_canfd]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
We tell driver developers to always pass NAPI_POLL_WEIGHT
as the weight to netif_napi_add(). This may be confusing
to newcomers, drop the weight argument, those who really
need to tweak the weight can use netif_napi_add_weight().
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for CAN
Link: https://lore.kernel.org/r/20220927132753.750069-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To simplify the testing in user space all struct canfd_frame's provided by
the CAN subsystem of the Linux kernel now have the CANFD_FDF flag set in
canfd_frame::flags.
NB: Handcrafted ETH_P_CANFD frames introduced via PF_PACKET socket might
not set this bit correctly. During the check for sufficient headroom in
PF_PACKET sk_buffs the uninitialized CAN sk_buff data structures are filled.
In the case of a CAN FD frame the CANFD_FDF flag is set accordingly.
As the CAN frame content is already zero initialized in alloc_canfd_skb()
the obsolete initialization of cf->flags in the CTU CAN FD driver has been
removed as it would overwrite the already set CANFD_FDF flag.
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-4-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Currently, some CAN drivers support hardware timestamping, some do
not. But userland has no method to query which features are supported
(aside maybe of getting RX messages and observe whether or not
hardware timestamps stay at zero).
The canonical way for a network driver to advertised what kind of
timestamping it supports is to implement ethtool_ops::get_ts_info().
This patch only targets the CAN drivers which *do not* support
hardware timestamping. For each of those CAN drivers, implement the
get_ts_info() using the generic ethtool_op_get_ts_info().
This way, userland can do:
| $ ethtool --show-time-stamping canX
to confirm the device timestamping capacities.
N.B. the drivers which support hardware timestamping will be migrated
in separate patches.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20220727101641.198847-6-mailhol.vincent@wanadoo.fr
[mkl: mscan: add missing mscan_ethtool_ops]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
