Add support for Xilinx CAN FD core.
The major difference from the previously supported cores is that there
are TX mailboxes instead of a TX FIFO and the RX FIFO access method is
different.
We only transmit one frame at a time to prevent the HW from reordering
frames (it uses CAN ID priority order).
Support for CAN FD protocol is not added yet.
v2: Removed unnecessary "rx-mode" DT property and wrapped some long
lines.
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Xilinx CAN FD cores are different enough from the previous Zynq and AXI
CAN cores that some refactoring of the driver is needed.
This commit contains most of the required refactoring to existing code
and should not alter behavior on existing supported HW.
The changes are:
- Reading and writing to frame registers is parametrized to allow
reading/writing a different frame in the future.
- Slightly misleading (as it did not specify *all* the interrupts
supported by the HW) XCAN_INTR_ALL is replaced with specifying the
interrupts inline in interrupt enabling code.
- xcan_devtype_data.caps is renamed to xcan_devtype_data.flags to allow
for flags that define alternative functionality (e.g. mailboxes vs.
FIFO) instead of purely additive capabilities.
- can_bittiming_const is added to xcan_devtype_data as CAN FD cores will
have wider setting ranges.
- bus_clk clock name is now determined through xcan_devtype_data instead
of comparing compatible string in probe().
- xcan_devtype_data is added to xcan_priv to allow flag checks after
probe().
- XCAN_CAP_WATERMARK is now XCAN_FLAG_TXFEMP. CAN FD cores have
watermark support but no TXFEMP interrupt, which is what we are
actually interested in.
- xcan_start_xmit() is split to in two parts to prepare for TX mailboxes
instead of FIFO in CAN FD cores.
v2: Wrapped some long lines in xcan_write_frame().
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The driver updates stats.tx_bytes in start_xmit() even though it could
do so in TX interrupt handler.
Change the code to update tx_bytes in the interrupt handler, using the
return value of can_get_echo_skb().
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Replace some custom code with a call to can_change_state().
This subtly changes the error reporting behavior when both RX and TX
error counters indicate the same state.
Previously, if both RX and TX counters indicated the same state:
- if overall state is PASSIVE, report CAN_ERR_CRTL_RX_PASSIVE
- if overall state is WARNING, report CAN_ERR_CRTL_TX_WARNING or
CAN_ERR_CRTL_RX_WARNING depending on which counter is higher,
or CAN_ERR_CRTL_RX_WARNING if the counters have the same value.
After this commit:
- report RX_* or TX_* depending on which counter is higher, or both if
the counters have exactly the same value.
This behavior is consistent with many other CAN drivers that use this
same code pattern.
Tested with the integrated CAN on Zynq-7000 SoC.
v2: Simplify resolving states as suggested by Andri Yngvason.
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The xilinx_can driver currently increments error-warning and
error-passive statistics on every error interrupt regardless of whether
the interface was already in the same state. Similarly, the error frame
sent on error interrupts is always sent with
CAN_ERR_CRTL_(RX|TX)_(PASSIVE|WARNING) bit set.
To make the error-warning and error-passive statistics more useful, add
a check to only set the error state when the state has actually been
changed.
Tested with the integrated CAN on Zynq-7000 SoC.
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The method ndo_start_xmit() is defined as returning an 'netdev_tx_t',
which is a typedef for an enum type, but the implementation in this
driver returns an 'int'.
Fix this by returning 'netdev_tx_t' in this driver too.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
There are several issues with the suspend/resume handling code of the
driver:
- The device is attached and detached in the runtime_suspend() and
runtime_resume() callbacks if the interface is running. However,
during xcan_chip_start() the interface is considered running,
causing the resume handler to incorrectly call netif_start_queue()
at the beginning of xcan_chip_start(), and on xcan_chip_start() error
return the suspend handler detaches the device leaving the user
unable to bring-up the device anymore.
- The device is not brought properly up on system resume. A reset is
done and the code tries to determine the bus state after that.
However, after reset the device is always in Configuration mode
(down), so the state checking code does not make sense and
communication will also not work.
- The suspend callback tries to set the device to sleep mode (low-power
mode which monitors the bus and brings the device back to normal mode
on activity), but then immediately disables the clocks (possibly
before the device reaches the sleep mode), which does not make sense
to me. If a clean shutdown is wanted before disabling clocks, we can
just bring it down completely instead of only sleep mode.
Reorganize the PM code so that only the clock logic remains in the
runtime PM callbacks and the system PM callbacks contain the device
bring-up/down logic. This makes calling the runtime PM callbacks during
e.g. xcan_chip_start() safe.
The system PM callbacks now simply call common code to start/stop the
HW if the interface was running, replacing the broken code from before.
xcan_chip_stop() is updated to use the common reset code so that it will
wait for the reset to complete. Reset also disables all interrupts so do
not do that separately.
Also, the device_may_wakeup() checks are removed as the driver does not
have wakeup support.
Tested on Zynq-7000 integrated CAN.
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
xcan_interrupt() clears ERROR|RXOFLV|BSOFF|ARBLST interrupts if any of
them is asserted. This does not take into account that some of them
could have been asserted between interrupt status read and interrupt
clear, therefore clearing them without handling them.
Fix the code to only clear those interrupts that it knows are asserted
and therefore going to be processed in xcan_err_interrupt().
Fixes: b1201e44f5 ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
RX overflow interrupt (RXOFLW) is disabled even though xcan_interrupt()
processes it. This means that an RX overflow interrupt will only be
processed when another interrupt gets asserted (e.g. for RX/TX).
Fix that by enabling the RXOFLW interrupt.
Fixes: b1201e44f5 ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The xilinx_can driver assumes that the TXOK interrupt only clears after
it has been acknowledged as many times as there have been successfully
sent frames.
However, the documentation does not mention such behavior, instead
saying just that the interrupt is cleared when the clear bit is set.
Similarly, testing seems to also suggest that it is immediately cleared
regardless of the amount of frames having been sent. Performing some
heavy TX load and then going back to idle has the tx_head drifting
further away from tx_tail over time, steadily reducing the amount of
frames the driver keeps in the TX FIFO (but not to zero, as the TXOK
interrupt always frees up space for 1 frame from the driver's
perspective, so frames continue to be sent) and delaying the local echo
frames.
The TX FIFO tracking is also otherwise buggy as it does not account for
TX FIFO being cleared after software resets, causing
BUG!, TX FIFO full when queue awake!
messages to be output.
There does not seem to be any way to accurately track the state of the
TX FIFO for local echo support while using the full TX FIFO.
The Zynq version of the HW (but not the soft-AXI version) has watermark
programming support and with it an additional TX-FIFO-empty interrupt
bit.
Modify the driver to only put 1 frame into TX FIFO at a time on soft-AXI
and 2 frames at a time on Zynq. On Zynq the TXFEMP interrupt bit is used
to detect whether 1 or 2 frames have been sent at interrupt processing
time.
Tested with the integrated CAN on Zynq-7000 SoC. The 1-frame-FIFO mode
was also tested.
An alternative way to solve this would be to drop local echo support but
keep using the full TX FIFO.
v2: Add FIFO space check before TX queue wake with locking to
synchronize with queue stop. This avoids waking the queue when xmit()
had just filled it.
v3: Keep local echo support and reduce the amount of frames in FIFO
instead as suggested by Marc Kleine-Budde.
Fixes: b1201e44f5 ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The xilinx_can driver contains no mechanism for propagating recovery
from CAN_STATE_ERROR_WARNING and CAN_STATE_ERROR_PASSIVE.
Add such a mechanism by factoring the handling of
XCAN_STATE_ERROR_PASSIVE and XCAN_STATE_ERROR_WARNING out of
xcan_err_interrupt and checking for recovery after RX and TX if the
interface is in one of those states.
Tested with the integrated CAN on Zynq-7000 SoC.
Fixes: b1201e44f5 ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If the device gets into a state where RXNEMP (RX FIFO not empty)
interrupt is asserted without RXOK (new frame received successfully)
interrupt being asserted, xcan_rx_poll() will continue to try to clear
RXNEMP without actually reading frames from RX FIFO. If the RX FIFO is
not empty, the interrupt will not be cleared and napi_schedule() will
just be called again.
This situation can occur when:
(a) xcan_rx() returns without reading RX FIFO due to an error condition.
The code tries to clear both RXOK and RXNEMP but RXNEMP will not clear
due to a frame still being in the FIFO. The frame will never be read
from the FIFO as RXOK is no longer set.
(b) A frame is received between xcan_rx_poll() reading interrupt status
and clearing RXOK. RXOK will be cleared, but RXNEMP will again remain
set as the new message is still in the FIFO.
I'm able to trigger case (b) by flooding the bus with frames under load.
There does not seem to be any benefit in using both RXNEMP and RXOK in
the way the driver does, and the polling example in the reference manual
(UG585 v1.10 18.3.7 Read Messages from RxFIFO) also says that either
RXOK or RXNEMP can be used for detecting incoming messages.
Fix the issue and simplify the RX processing by only using RXNEMP
without RXOK.
Tested with the integrated CAN on Zynq-7000 SoC.
Fixes: b1201e44f5 ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The xilinx_can driver performs a software reset when an RX overrun is
detected. This causes the device to enter Configuration mode where no
messages are received or transmitted.
The documentation does not mention any need to perform a reset on an RX
overrun, and testing by inducing an RX overflow also indicated that the
device continues to work just fine without a reset.
Remove the software reset.
Tested with the integrated CAN on Zynq-7000 SoC.
Fixes: b1201e44f5 ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
napi_complete_done() allows to opt-in for gro_flush_timeout,
added back in linux-3.19, commit 3b47d30396
("net: gro: add a per device gro flush timer")
This allows for more efficient GRO aggregation without
sacrifying latencies.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/renesas/ravb_main.c
kernel/bpf/syscall.c
net/ipv4/ipmr.c
All three conflicts were cases of overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of enabling/disabling clocks at several locations in the driver,
Use the runtime_pm framework. This consolidates the actions for runtime PM
In the appropriate callbacks and makes the driver more readable and mantainable.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The assignment 'cf->data[2] |= CAN_ERR_PROT_UNSPEC' used at CAN error message
creation time is obsolete as CAN_ERR_PROT_UNSPEC is zero and cf->data[2] is
initialized with zero in alloc_can_err_skb() anyway.
So we could either assign 'cf->data[2] = CAN_ERR_PROT_UNSPEC' correctly or we
can remove the obsolete OR operation entirely.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As Dan Carpenter reported in http://marc.info/?l=linux-can&m=144793696016187
the assignment of the error location in CAN error messages had some bit wise
overlaps. Indeed the value to be assigned in data[3] is no bitfield but defines
a single value which points to a location inside the CAN frame on the wire.
This patch fixes the assignments for the error locations in error messages.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Using IDR_SRR in RXFIFO_ID to test for the presence of data is only
valid for standard frames. For extended frames the bit is always 1 and
IDR_RTR should be used instead. This patch switches the check to use
CAN_RTR_FLAG which is correctly set when reading the ID.
The patch also changes the DW1/DW2 to be read unconditionally, since
this is necessary to remove the frame from the RXFIFO.
Signed-off-by: Jeppe Ledet-Pedersen <jlp@gomspace.com>
Acked-by: Kedareswara rao Appana <appanad@xilinx.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes, just
removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There are
some ath9k patches coming in through this tree that have been acked by
the wireless maintainers as they relied on the debugfs changes.
Everything has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core update from Greg KH:
"Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes,
just removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There
are some ath9k patches coming in through this tree that have been
acked by the wireless maintainers as they relied on the debugfs
changes.
Everything has been in linux-next for a while"
* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
fs: debugfs: add forward declaration for struct device type
firmware class: Deletion of an unnecessary check before the function call "vunmap"
firmware loader: fix hung task warning dump
devcoredump: provide a one-way disable function
device: Add dev_<level>_once variants
ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
ath: use seq_file api for ath9k debugfs files
debugfs: add helper function to create device related seq_file
drivers/base: cacheinfo: remove noisy error boot message
Revert "core: platform: add warning if driver has no owner"
drivers: base: support cpu cache information interface to userspace via sysfs
drivers: base: add cpu_device_create to support per-cpu devices
topology: replace custom attribute macros with standard DEVICE_ATTR*
cpumask: factor out show_cpumap into separate helper function
driver core: Fix unbalanced device reference in drivers_probe
driver core: fix race with userland in device_add()
sysfs/kernfs: make read requests on pre-alloc files use the buffer.
sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
fs: sysfs: return EGBIG on write if offset is larger than file size
...
The variable err was of the type u32. It was being compared with < 0, and being
an unsigned variable the comparison would have been always false.
Moreover, err was getting the return value from set_reset_mode() and
xcan_set_bittiming(), and both are returning int.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds xilinx CAN controller support. This driver supports both ZYNQ
CANPS and Soft IP AXI CAN controller.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Anssi Hannula