Give FIFO writes the same treatment as reads to avoid fixed costs of
individual transfers on a slow bus (e.g., tcan4x5x).
Link: https://lore.kernel.org/r/20210817050853.14875-4-matt@bitbashing.io
Signed-off-by: Matt Kline <matt@bitbashing.io>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
On peripherals communicating over a relatively slow SPI line
(e.g. tcan4x5x), individual transfers have high fixed costs.
This causes the driver to spend most of its time waiting between
transfers and severely limits throughput.
Reduce these overheads by reading more than one word at a time.
Writing could get a similar treatment in follow-on commits.
Link: https://lore.kernel.org/r/20210817050853.14875-3-matt@bitbashing.io
Signed-off-by: Matt Kline <matt@bitbashing.io>
[mkl: remove __packed from struct id_and_dlc]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If FIFO reads or writes fail due to the underlying regmap (e.g., SPI)
I/O, propagate that up to the m_can driver, log an error, and disable
interrupts, similar to the mcp251xfd driver.
While reworking the FIFO functions to add this error handling,
add support for bulk reads and writes of multiple registers.
Link: https://lore.kernel.org/r/20210817050853.14875-2-matt@bitbashing.io
Signed-off-by: Matt Kline <matt@bitbashing.io>
[mkl: re-wrap long lines, remove WARN_ON, convert to netdev block comments]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch fixes the commenting style in the m_can driver.
Fixes: 1be37d3b04 ("can: m_can: fix periph RX path: use rx-offload to ensure skbs are sent from softirq context")
Fixes: df06fd6782 ("can: m_can: m_can_chip_config(): enable and configure internal timestamps")
Link: https://lore.kernel.org/r/20210819111703.599686-2-mkl@pengutronix.de
Cc: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch fixes the setting of the M_CAN_DBTP register contents:
- use DBTP_ (the data bitrate macros) instead of NBTP_ which area used
for the nominal bitrate
- do not overwrite possibly-existing DBTP_TDC flag by ORing reg_btp
instead of overwriting
Link: https://lore.kernel.org/r/FRYP281MB06140984ABD9994C0AAF7433D1F69@FRYP281MB0614.DEUP281.PROD.OUTLOOK.COM
Fixes: 20779943a0 ("can: m_can: use bits.h macros for all regmasks")
Cc: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Cc: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Signed-off-by: Hussein Alasadi <alasadi@arecs.eu>
[mkl: update patch description, update indention]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Since commit aee2b3ccc8 ("can: tcan4x5x: fix bittiming const, use
common bittiming from m_can driver") there is no use of the device
specific bit timing parameters (m_can_classdev::bit_timing and struct
m_can_classdev::data_timing).
This patch removes the support for custom bit timing from the driver,
as the common bit timing works for all known IP core implementations.
Cc: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Link: https://lore.kernel.org/r/20210616102811.2449426-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Use the devm_platform_ioremap_resource_byname() helper instead of
calling platform_get_resource_byname() and devm_ioremap_resource()
separately.
Link: https://lore.kernel.org/r/20210603073441.2983497-1-yangyingliang@huawei.com
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add support for implementing transceiver node as phy. The max_bitrate
is obtained by getting a phy attribute.
Link: https://lore.kernel.org/r/20210724174001.553047-1-mkl@pengutronix.de
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
After reading all CAN frames from the controller in the IRQ handler
and storing them into a skb_queue, the driver calls napi_schedule().
In the napi poll function the skb from the skb_queue are then pushed
into the networking stack.
However if napi_schedule() is called from a threaded IRQ handler this
triggers the following error:
| NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!!
To avoid this, create a new rx-offload
function (can_rx_offload_threaded_irq_finish()) with a call to
local_bh_disable()/local_bh_enable() around the napi_schedule() call.
Convert all drivers that call can_rx_offload_irq_finish() from
threaded IRQ context to can_rx_offload_threaded_irq_finish().
Link: https://lore.kernel.org/r/20210724204745.736053-4-mkl@pengutronix.de
Suggested-by: Daniel Glöckner <dg@emlix.com>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Adding a skb to the skb_queue in rx-offload requires to take a lock.
This commit avoids this by adding an unlocked skb queue that is
appended at the end of the ISR. Having one lock at the end of the ISR
should be OK as the HW is empty, not about to overflow.
Link: https://lore.kernel.org/r/20210724204745.736053-2-mkl@pengutronix.de
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Co-developed-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Introduce masks for the three RXESC fields (RBDS, F1DS, F0DS) and the
one TXESC field (TBDS). Update m_can_chip_config() to explicitly set all
four fields to the 64-byte option (0x7) (and these defs are renamed to
be more concise).
This is an improvement in maintainability, and also makes it easier to
implement more flexible configuration of the M_CAN buffers in the
future.
Link: https://lore.kernel.org/r/20210504125123.500553-4-torin@maxiluxsystems.com
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Ensures that the different CCCR regmasks for m_can revs 3.0.x, 3.1.x,
3.2.x and 3.3.x are clearly distinguishable. Removes incorrect
CCCR_CANFD define. Adds bit fields UTSU and WMM for rev 3.3.x, for
completeness.
Link: https://lore.kernel.org/r/20210504125123.500553-3-torin@maxiluxsystems.com
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This updates m_can.c to exclusively use GENMASK, FIELD_GET, FIELD_PREP
and FIELD_MAX for regmask ops, as is convention in the current kernel
(far less error-prone, far more concise).
Link: https://lore.kernel.org/r/20210504125123.500553-2-torin@maxiluxsystems.com
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The m_can_start_xmit() function checks if the cdev->tx_skb is NULL and
returns with NETDEV_TX_BUSY in case tx_sbk is not NULL.
There is a race condition in the m_can_tx_work_queue(), where first
the skb is send to the driver and then the case tx_sbk is set to NULL.
A TX complete IRQ might come in between and wake the queue, which
results in tx_skb not being cleared yet.
Fixes: f524f829b7 ("can: m_can: Create a m_can platform framework")
Tested-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In commit 1be37d3b04 ("can: m_can: fix periph RX path: use
rx-offload to ensure skbs are sent from softirq context") the RX path
for peripherals (i.e. SPI based m_can controllers) was converted to
the rx-offload infrastructure. However, the error handling for
can_rx_offload_queue_sorted() was forgotten.
can_rx_offload_queue_sorted() will return with an error if the
internal queue is full.
This patch adds the missing error handling, by increasing the
rx_fifo_errors.
Fixes: 1be37d3b04 ("can: m_can: fix periph RX path: use rx-offload to ensure skbs are sent from softirq context")
Link: https://lore.kernel.org/r/20210401084515.1455013-1-mkl@pengutronix.de
Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1503583 ("Error handling issues")
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
linux/regmap.h has been included at line 13, so remove the duplicate
one at line 14.
Fixes: 67def4ef8b ("can: tcan4x5x: move regmap code into seperate file")
Link: https://lore.kernel.org/r/20210323021026.140460-1-wanjiabing@vivo.com
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
For peripheral devices, m_can sent skbs directly from a threaded irq
instead of from a softirq context, breaking the tcan4x5x peripheral
driver completely. This patch transitions the driver to use the
rx-offload helper for peripherals, ensuring the skbs are sent from the
correct context, with h/w timestamping to ensure correct ordering.
Link: https://lore.kernel.org/r/20210308102427.63916-4-torin@maxiluxsystems.com
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
[mkl: m_can_class_register(): update error handling]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This is a prerequisite for transitioning the m_can driver to rx-offload,
which works best with TX and RX timestamps.
The timestamps provided by M_CAN are 16-bit, timed according to the
nominal bit timing, and may be prescaled by a multiplier up to 16. We
choose the highest prescalar so that the timestamp wraps every 2^20 bit
times, or 209 ms at a bus speed of 5 Mbit/s. Timestamps will have a
precision of 16 bit times.
Link: https://lore.kernel.org/r/20210308102427.63916-3-torin@maxiluxsystems.com
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If the CAN net device has been successfully allocated, its private
data structure is impossible to be empty, remove this redundant error
return judgment.
Link: https://lore.kernel.org/r/20210205072559.13241-2-xulin.sun@windriver.com
Signed-off-by: Xulin Sun <xulin.sun@windriver.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In order to implement byte queue limits (bql) in CAN drivers, the
length of the CAN frame needs to be passed into the networking stack
even if the transmission failed for some reason.
To avoid to calculate this length twice, extend can_free_echo_skb() to
return that value. Convert all users of this function, too.
This patch is the natural extension of commit:
| 9420e1d495 ("can: dev: can_get_echo_skb(): extend to return can
| frame length")
Link: https://lore.kernel.org/r/20210319142700.305648-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
For M_CAN peripherals, m_can_rx_handler() was called with quota = 1,
which caused any error handling to block RX from taking place until
the next time the IRQ handler is called. This had been observed to
cause RX to be blocked indefinitely in some cases.
This is fixed by calling m_can_rx_handler with a sensibly high quota.
Fixes: f524f829b7 ("can: m_can: Create a m_can platform framework")
Link: https://lore.kernel.org/r/20210303144350.4093750-1-torin@maxiluxsystems.com
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Message loss from RX FIFO 0 is already handled in
m_can_handle_lost_msg(), with netdev output included.
Removing this warning also improves driver performance under heavy
load, where m_can_do_rx_poll() may be called many times before this
interrupt is cleared, causing this message to be output many
times (thanks Mariusz Madej for this report).
Fixes: e0d1f4816f ("can: m_can: add Bosch M_CAN controller support")
Link: https://lore.kernel.org/r/20210303103151.3760532-1-torin@maxiluxsystems.com
Reported-by: Mariusz Madej <mariusz.madej@xtrack.com>
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch prevents a potentially destructive race condition. The
device is fully operational on the bus after entering Normal Mode, so
zeroing the MRAM after entering this mode may lead to loss of
information, e.g. new received messages.
This patch fixes the problem by first initializing the MRAM, then
bringing the device into Normale Mode.
Fixes: 5443c226ba ("can: tcan4x5x: Add tcan4x5x driver to the kernel")
Link: https://lore.kernel.org/r/20210226163440.313628-1-torin@maxiluxsystems.com
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The first member of struct tcan4x5x_map_buf is the struct tcan4x5x_buf_cmd,
which has a size of 4 bytes. It's followed by an array of u8. The compiler
places the array directly after the struct tcan4x5x_buf_cmd.
This patch removes the not needed attribute __packed from the struct
tcan4x5x_map_buf.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20210113203955.912916-1-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.
To avoid to calculate this length twice, extend can_get_echo_skb() to return
that value. Convert all users of this function, too.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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>
According to the TCAN4550 datasheet "SLLSF91 - DECEMBER 2018" the tcan4x5x has
the same bittiming constants as a m_can revision 3.2.x/3.3.0.
The tcan4x5x chip I'm using identifies itself as m_can revision 3.2.1, so
remove the tcan4x5x specific bittiming values and rely on the values in the
m_can driver, which are selected according to core revision.
Fixes: 5443c226ba ("can: tcan4x5x: Add tcan4x5x driver to the kernel")
Cc: Dan Murphy <dmurphy@ti.com>
Reviewed-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215103238.524029-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In m_can_class_register() the clock is started, but stopped on exit. When
calling m_can_class_unregister(), the clock is stopped a second time.
This patch removes the erroneous m_can_clk_stop() in m_can_class_unregister().
Fixes: f524f829b7 ("can: m_can: Create a m_can platform framework")
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Sriram Dash <sriram.dash@samsung.com>
Reviewed-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215103238.524029-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds back support for half-duplex controllers, which was removed in
the last patch.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-17-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch reworks the SPI access and fixes several probems:
- tcan4x5x_regmap_gather_write(), tcan4x5x_regmap_read():
Do not place variable "addr" on stack and use it as buffer for SPI
transfer. Buffers for SPI transfers must be allocated from DMA save
memory.
- tcan4x5x_regmap_gather_write(), tcan4x5x_regmap_read():
Halfe number of SPI transfers by using a single buffer + memcpy().
This improves the performance, especially on SPI controllers, which
use interrupt based transfers.
- Use "8" bits per word, not "32". This makes it possible to use this
driver on SoCs like the Raspberry Pi, which SPI host controller
drivers only support 8 bits per word.
Note: this breaks half duplex only controllers. Support for them will be
re-added in the next patch.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-16-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The memory space of the chip is not fully populated, so add a regmap range
table to document this.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-15-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The tcan4x5x chip support bulk read/write, but as the length field is only 8
bits wide, the maximum is 256. A length of 0 is treated as 256.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch sets the regmap stide to 4, as the chip only supports access on 32
bit alligned access.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-13-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch replaces the context pointer of the regmap callback functions by a
pointer to the spi_device. This saves one level of indirection in the
callbacks.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-11-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch simplifies the tcan4x5x_regmap_write(0 function by removing not
needed casts and replaces hardcoded "4" by appropriate sizeof()s.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-10-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch renames the regmap_spi_gather_write() function to
tcan4x5x_regmap_gather_write(). Now it has a "tcan4x5x_" prefix as all other
functions in this driver.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-9-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The driver doesn't use regmap async support, so remove the stubs.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-8-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
With C99 initializers, all non mentioned members are initialzied to 0, so
remove not needed initialization of read_flag_mask.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch marks the struct regmap_bus tcan4x5x_bus as constant.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This is a preparation patch to move the regmap related code into a seperate
file. This patch removes the tcan4x5x.c to tcan4x5x-core.c.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-4-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch beautifies the indention of the tcan4x5x_of_match and
tcan4x5x_id_table.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch replaces the DEVICE_NAME macro by KBUILD_MODNAME and removed the
superfluous DEVICE_NAME.
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://lore.kernel.org/r/20201215231746.1132907-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The m_can driver's suspend and resume functions (m_can_class_suspend() and
m_can_class_resume()) make use of dev_get_drvdata() and assume that the drvdata
is a pointer to the struct net_device.
With upcoming conversion of the tcan4x5x driver to pm_runtime this assumption
is no longer valid. As the suspend and resume functions actually need a struct
m_can_classdev pointer, change the m_can_platform and the m_can_pci driver to
hold a pointer to struct m_can_classdev instead, as the tcan4x5x driver already
does.
Link: https://lore.kernel.org/r/20201212175518.139651-8-mkl@pengutronix.de
Reviewed-by: Sean Nyekjaer <sean@geanix.com>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Matt Kline