Add a frame_len argument to can_put_echo_skb() which is used to save length of
the CAN frame into field frame_len of struct can_skb_priv so that it can be
later used after transmission completion. Convert all users of this function,
too.
Drivers which implement BQL call can_put_echo_skb() with the output of
can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an
input (in the same way that NULL would be given to can_get_echo_skb()). This
way, we have a nice symmetry between the two echo functions.
Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
The System Controller Firmware (SCFW) is a low-level system function
which runs on a dedicated Cortex-M core to provide power, clock, and
resource management. It exists on some i.MX8 processors. e.g. i.MX8QM
(QM, QP), and i.MX8QX (QXP, DX). SCU driver manages the IPC interface
between host CPU and the SCU firmware running on M4.
For i.MX8QM, stop mode request is controlled by System Controller Unit(SCU)
firmware, this patch introduces FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW quirk
for this function.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20201106105627.31061-6-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The flexcan driver runs only on DT platforms, so simplify the code by using
of_device_get_match_data() to retrieve the driver data and also by removing the
unused id_table.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20201128132855.7724-1-festevam@gmail.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
There haven been reports, that the flexcan_close() soradically hangs during
simultanious ifdown, sending of CAN messages and probably open CAN bus:
| (__schedule) from [<808bbd34>] (schedule+0x90/0xb8)
| (schedule) from [<808bf274>] (schedule_timeout+0x1f8/0x24c)
| (schedule_timeout) from [<8016be44>] (msleep+0x18/0x1c)
| (msleep) from [<80746a64>] (napi_disable+0x60/0x70)
| (napi_disable) from [<8052fdd0>] (flexcan_close+0x2c/0x140)
| (flexcan_close) from [<80744930>] (__dev_close_many+0xb8/0xd8)
| (__dev_close_many) from [<8074db9c>] (__dev_change_flags+0xd0/0x1a0)
| (__dev_change_flags) from [<8074dc84>] (dev_change_flags+0x18/0x48)
| (dev_change_flags) from [<80760c24>] (do_setlink+0x44c/0x7b4)
| (do_setlink) from [<80761560>] (rtnl_newlink+0x374/0x68c)
I was unable to reproduce the issue, but a cleanup of the flexcan close
sequence has probably fixed the problem at the reporting user.
This patch changes the sequence in flexcan_close() to:
- stop the TX queue
- disable the interrupts on the chip level and wait via free_irq()
synchronously for the interrupt handler to finish
- disable RX offload, which disables synchronously NAPI
- disable the flexcan on the chip level
- free RX offload
- disable the transceiver
- close the CAN device
- disable the clocks
Link: https://lore.kernel.org/r/20201119100917.3013281-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch changes the order in which the flexcan controller is brought up
during flexcan_open(). It makes sure that the chip is completely initialized
before the IRQs are requested and finally enabled.
Link: https://lore.kernel.org/r/20201119100917.3013281-5-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The function flexcan_chip_start() first configures the CAN controller and then
enables the interrupt, flexcan_chip_stop() does the opposite.
In an upcoming patch the order of operations in flexcan_open() and
flexcan_close() are changed. This requires
flexcan_chip_start()/flexcan_chip_stop_disable_on_error() and
flexcan_chip_interrupts_{enable,disable}() to be independent of each other.
This patch moves the enabling of the interrupts from flexcan_chip_start() to
its callers flexcan_open() and flexcan_resume(). Likewise the disabling of the
interrupts is moved from __flexcan_chip_stop() to its indirect callers
flexcan_close() and flexcan_suspend().
Link: https://lore.kernel.org/r/20201119100917.3013281-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The upcoming patches are going to move the enabling and disabling of the
interrupts. Introduce convenience functions to make these patches simpler.
Link: https://lore.kernel.org/r/20201119100917.3013281-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch intends to rename FLEXCAN_QUIRK_SETUP_STOP_MODE quirk
to FLEXCAN_QUIRK_SETUP_STOP_MODE_GRP for non-scu SoCs, coming patch will
add quirk for scu SoCs.
For non-scu SoCs, setup stop mode with GPR register.
For scu SoCs, setup stop mode with SCU firmware.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20201106105627.31061-4-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The helper functions can_len2dlc and can_dlc2len are only relevant for
CAN FD data length code (DLC) conversion.
To fit the introduced can_cc_dlc2len for Classical CAN we rename:
can_dlc2len -> can_fd_dlc2len to get the payload length from the DLC
can_len2dlc -> can_fd_len2dlc to get the DLC from the payload length
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-6-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The macro was always used together with can_dlc2len() which sanitizes the
given dlc value on its own.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-4-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The get_can_dlc() macro is used to ensure the payload length information of
the Classical CAN frame to be max 8 bytes (the CAN_MAX_DLEN).
Rename the macro and use the correct constant in preparation of the len/dlc
cleanup for Classical CAN frames.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If the CAN controller goes into bus off, the do_set_mode() callback with
CAN_MODE_START can be used to recover the controller, which then calls
flexcan_chip_start(). If configured, this is done automatically by the
framework or manually by the user.
In flexcan_chip_start() there is an explicit call to
flexcan_transceiver_enable(), which does a regulator_enable() on the
transceiver regulator. This results in a net usage counter increase, as there
is no corresponding flexcan_transceiver_disable() in the bus off code path.
This further leads to the transceiver stuck enabled, even if the CAN interface
is shut down.
To fix this problem the
flexcan_transceiver_enable()/flexcan_transceiver_disable() are moved out of
flexcan_chip_start()/flexcan_chip_stop() into flexcan_open()/flexcan_close().
Fixes: e955cead03 ("CAN: Add Flexcan CAN controller driver")
Link: https://lore.kernel.org/r/20201118150148.2664024-1-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
pm_runtime_get_sync() will increment pm usage at first and it will resume the
device later. If runtime of the device has error or device is in inaccessible
state(or other error state), resume operation will fail. If we do not call put
operation to decrease the reference, it will result in reference leak in the
two functions flexcan_get_berr_counter() and flexcan_open().
Moreover, this device cannot enter the idle state and always stay busy or other
non-idle state later. So we should fix it through adding
pm_runtime_put_noidle().
Fixes: ca10989632 ("can: flexcan: implement can Runtime PM")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201108083000.2599705-1-zhangqilong3@huawei.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In the patch
d9b081e3fc ("can: flexcan: remove ack_grp and ack_bit handling from driver")
the unused ack_grp and ack_bit were removed from the driver. However in the
comment, the "req_bit" was accidentally removed, too.
This patch adds back the "req_bit" bit.
Fixes: d9b081e3fc ("can: flexcan: remove ack_grp and ack_bit handling from driver")
Reported-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: http://lore.kernel.org/r/20201014114810.2911135-1-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
For SoCs with ECC supported, even use FLEXCAN_QUIRK_DISABLE_MECR quirk to
disable non-correctable errors interrupt and freeze mode, had better use
FLEXCAN_QUIRK_SUPPORT_ECC quirk to initialize all memory.
Fixes: cdce844865 ("can: flexcan: add vf610 support for FlexCAN")
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20201020155402.30318-6-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
After double check with Layerscape CAN owner (Pankaj Bansal), confirm
that LX2160A indeed supports ECC feature, so correct the feature table.
For SoCs with ECC supported, even use FLEXCAN_QUIRK_DISABLE_MECR quirk to
disable non-correctable errors interrupt and freeze mode, had better use
FLEXCAN_QUIRK_SUPPORT_ECC quirk to initialize all memory.
Fixes: 2c19bb43e5 ("can: flexcan: add lx2160ar1 support")
Cc: Pankaj Bansal <pankaj.bansal@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20201020155402.30318-5-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
After double check with Layerscape CAN owner (Pankaj Bansal), confirm that
LS1021A doesn't support ECC feature, so remove FLEXCAN_QUIRK_DISABLE_MECR
quirk.
Fixes: 99b7668c04 ("can: flexcan: adding platform specific details for LS1021A")
Cc: Pankaj Bansal <pankaj.bansal@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20201020155402.30318-4-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Since commit:
048e3a34a2 can: flexcan: poll MCR_LPM_ACK instead of GPR ACK for stop mode acknowledgment
the driver polls the IP core's internal bit MCR[LPM_ACK] as stop mode
acknowledge and not the acknowledgment on chip level.
This means the 4th and 5th value of the property "fsl,stop-mode" isn't used
anymore. This patch removes the used "ack_gpr" and "ack_bit" from the driver.
Link: http://lore.kernel.org/r/20201006203748.1750156-15-mkl@pengutronix.de
Fixes: 048e3a34a2 ("can: flexcan: poll MCR_LPM_ACK instead of GPR ACK for stop mode acknowledgment")
Cc: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
One issue was reported at a baremetal environment, which is used for
FPGA verification. "The first transfer will fail for extended ID
format(for both 2.0B and FD format), following frames can be transmitted
and received successfully for extended format, and standard format don't
have this issue. This issue occurred randomly with high possiblity, when
it occurs, the transmitter will detect a BIT1 error, the receiver a CRC
error. According to the spec, a non-correctable error may cause this
transfer failure."
With FLEXCAN_QUIRK_DISABLE_MECR quirk, it supports correctable errors,
disable non-correctable errors interrupt and freeze mode. Platform has
ECC hardware support, but select this quirk, this issue may not come to
light. Initialize all FlexCAN memory before accessing them, at least it
can avoid non-correctable errors detected due to memory uninitialized.
The internal region can't be initialized when the hardware doesn't support
ECC.
According to IMX8MPRM, Rev.C, 04/2020. There is a NOTE at the section
11.8.3.13 Detection and correction of memory errors:
"All FlexCAN memory must be initialized before starting its operation in
order to have the parity bits in memory properly updated. CTRL2[WRMFRZ]
grants write access to all memory positions that require initialization,
ranging from 0x080 to 0xADF and from 0xF28 to 0xFFF when the CAN FD feature
is enabled. The RXMGMASK, RX14MASK, RX15MASK, and RXFGMASK registers need to
be initialized as well. MCR[RFEN] must not be set during memory initialization."
Memory range from 0x080 to 0xADF, there are reserved memory (unimplemented
by hardware, e.g. only configure 64 MBs), these memory can be initialized or not.
In this patch, initialize all flexcan memory which includes reserved memory.
In this patch, create FLEXCAN_QUIRK_SUPPORT_ECC for platforms which has ECC
feature. If you have a ECC platform in your hand, please select this
qurik to initialize all flexcan memory firstly, then you can select
FLEXCAN_QUIRK_DISABLE_MECR to only enable correctable errors.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20200929211557.14153-2-qiangqing.zhang@nxp.com
[mkl: wrap long lines]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The CAN-FD protocol allows the transmission and reception of data at a
higher bit rate than the nominal rate used in the arbitration phase when
the message's BRS bit is set.
The TDC mechanism is effective only during the data phase of FD frames
having BRS bit set. It has no effect either on non-FD frames, or on FD
frames transmitted at normal bit rate.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20190712075926.7357-7-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
ISO CAN FD is introduced to increase the failture detection capability
than non-ISO CAN FD. The non-ISO CAN FD is still supported by FlexCAN so
that it can be used mainly during an intermediate phase, for evaluation
and development purposes.
Therefore, it is strongly recommended to configure FlexCAN to the ISO
CAN FD protocol by setting the ISOCANFDEN field in the CTRL2 register.
NOTE: If you only set "fd on", driver will use ISO FD mode by default.
You should set "fd-non-iso on" after setting "fd on" if you want to use
NON ISO FD mode.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20190712075926.7357-6-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds CAN-FD mode support to the driver, it means that
payload size can extend up to 64 bytes.
Bit timing always set in the CBT register, not in the CTRL1 register any
more. This has an extend range of all CAN bit timing variables (PRESDIV,
PROPSEG, PSEG1, PSEG2 and RJW), which will improve the bit timing
accuracy.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
[mkl: move cbt-based bitrate support into separate function]
Link: https://lore.kernel.org/r/20200922144429.2613631-16-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch prepares for CAN FD mode, using struct canfd_frame can both
for classic format frame and fd format frame.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20190712075926.7357-3-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This is a patch prepares for the CAN-FD support. In a later patch the
setup for canfd bittiming will be added, with this patch the change is
easier to read.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200922144429.2613631-14-mkl@pengutronix.de
On the i.MX7D in LPSR mode, the controller will be powered off and the
configuration state is lost after system resume. Upcoming i.MX8QM/QXP
will also completely power off the domain, the controller state is lost
and needs restore, too. So we need to set the pinctrl state again and
re-start chip to re-configuration after resume.
For the wakeup case, it should not set pinctrl to sleep state by
pinctrl_pm_select_sleep_state.
If the interface is down before suspend, we don't need to re-configure
it as it will be configured if the interface is brought up later.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20191204113249.3381-7-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch implements error handling and propagates the error value of
flexcan_chip_stop(). This function will be called from flexcan_suspend()
in an upcoming patch in some SoCs which support LPSR mode.
Add a new function flexcan_chip_stop_disable_on_error() that tries to
disable the chip even in case of errors.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
[mkl: introduce flexcan_chip_stop_disable_on_error() and use it in flexcan_close()]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200922144429.2613631-11-mkl@pengutronix.de
commit cdce844865 ("can: flexcan: add vf610 support for FlexCAN")
From above commit by Stefan Agner, the patch just disables
non-correctable errors interrupt and freeze mode. It still can correct
the correctable errors since ECC enabled by default after reset (MECR[ECCDIS]=0,
enable memory error correct) if HW supports ECC.
commit 5e269324db ("can: flexcan: disable completely the ECC mechanism")
From above commit by Joakim Zhang, the patch disables ECC completely (assert
MECR[ECCDIS]) according to the explanation of FLEXCAN_QUIRK_DISABLE_MECR that
disable memory error detection. This cause correctable errors cannot be
corrected even HW supports ECC.
The error correction mechanism ensures that in this 13-bit word, errors
in one bit can be corrected (correctable errors) and errors in two bits can
be detected but not corrected (non-correctable errors). Errors in more than
two bits may not be detected.
If HW supports ECC, we can use this to correct the correctable errors detected
from FlexCAN memory. Then disable non-correctable errors interrupt and freeze
mode to avoid that put FlexCAN in freeze mode.
This patch adds correctable errors correction when HW supports ECC, and
modify explanation for FLEXCAN_QUIRK_DISABLE_MECR.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20200416093126.15242-1-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
CAN FD can transmit up to 8Mbps, but some transceivers only can support
5Mbps, so add check in driver.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20191030064245.12923-2-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As the transcevier regulator is optional, this patch switches from
devm_regulator_get() to devm_regulator_get_optional(). This gets rid of "using
dummy regulator" warning message from the regulator core, if no regulator is
available.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200922144429.2613631-8-mkl@pengutronix.de
As FLEXCAN_ESR_ALL_INT is for all bus errors and state change IRQ
sources, strictly speaking FLEXCAN_ESR_WAK_INT does not belong to these.
So add wakeup interrupt ack separately to existing ack of the
interrupts.
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20191204113249.3381-3-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Stop Mode is entered when Stop Mode is requested at chip level and
MCR[LPM_ACK] is asserted by the FlexCAN.
Double check with IP owner, the MCR[LPM_ACK] bit should be polled for
stop mode acknowledgment, not the acknowledgment from chip level which
is used to gate flexcan clocks.
This patch depends on:
b7603d080f ("can: flexcan: add low power enter/exit acknowledgment helper")
Fixes: 5f186c257f (can: flexcan: fix stop mode acknowledgment)
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v5.0
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The MCR[LPMACK] read-only bit indicates that FlexCAN is in a lower-power
mode (Disabled mode, Doze mode, Stop mode).
The CPU can poll this bit to know when FlexCAN has actually entered low
power mode. The low power enter/exit acknowledgment helper will reduce
code duplication for disabled mode, doze mode and stop mode.
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
When suspending, and there is still CAN traffic on the interfaces the
flexcan immediately wakes the platform again. As it should :-). But it
throws this error msg:
[ 3169.378661] PM: noirq suspend of devices failed
On the way down to suspend the interface that throws the error message
calls flexcan_suspend() but fails to call flexcan_noirq_suspend(). That
means flexcan_enter_stop_mode() is called, but on the way out of suspend
the driver only calls flexcan_resume() and skips flexcan_noirq_resume(),
thus it doesn't call flexcan_exit_stop_mode(). This leaves the flexcan
in stop mode, and with the current driver it can't recover from this
even with a soft reboot, it requires a hard reboot.
This patch fixes the deadlock when using self wakeup, by calling
flexcan_exit_stop_mode() from flexcan_resume() instead of
flexcan_noirq_resume().
This also fixes another issue: CAN frames are received out-of-order in
first IRQ handler run after wakeup.
The problem is that the wakeup latency from frame reception to the IRQ
handler (where the CAN frames are sorted by timestamp) is much bigger
than the time stamp counter wrap around time. This means it's
impossible to sort the CAN frames by timestamp.
The reason is that the controller exits stop mode during noirq resume,
which means it receives frames immediately, but interrupt handling is
still not possible.
So exit stop mode during resume stage instead of noirq resume fixes this
issue.
Fixes: de3578c198 ("can: flexcan: add self wakeup support")
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v5.0
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In the previous patch the function flexcan_write64() was introduced.
This patch replaces the open coded variant in flexcan_mailbox_read()
that marks a mailbox as read, by a single call to flexcan_write64().
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The flexcan IP core has up to 64 mailboxes, each one has a corresponding
interrupt bit in the iflag1 or iflag2 registers and a mask bit in the
imask1 or imask2 registers.
The driver will always use the last mailbox for TX, which falls into the iflag2
register.
To support CANFD the payload size has to increase to 64 bytes and the number of
mailboxes will decrease so much that the TX mailbox will be handled in the
iflag1 register.
This patch add support to handle the TX mailbox independent whether it's
in iflag1 or iflag2 by introducing th flexcan_read_reg_iflag_tx()
function, similar to flexcan_read_reg_iflag_rx(), for the read path.
For the write path the function flexcan_write64() is added.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The flexcan IP core has up to 64 mailboxes, each one has a corresponding
interrupt bit in the iflag1 or iflag2 registers and a mask bit in the
imask1 or imask2 registers.
In the timestamp (i.e. non FIFO) mode the driver needs to mask all non RX
interrupt sources, it uses the precomputed value rx_mask of struct flexcan_priv
for this.
In certain use cases, for example the CANFD mode, the contents of the iflag2
register is completely masked.
This patch optimizes the flexcan_read_reg_iflag_rx() function by not reading
the iflag1 or iflag2 register if the contents is masked.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Vincent Mailhol