Bosch M_CAN is CAN FD capable device. This patch implements the CAN
FD features include up to 64 bytes payload and bitrate switch function.
1) Change the Rx FIFO and Tx Buffer to 64 bytes for support CAN FD
up to 64 bytes payload. It's backward compatible with old 8 bytes
normal CAN frame.
2) Allocate can frame or canfd frame based on EDL bit
3) Bitrate Switch function is disabled by default and will be enabled
according to CANFD_BRS bit in cf->flags.
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The spec mentions there may be a delay until the value written to INIT can be
read back due to the synchronization mechanism between the two clock domains.
But it does not indicate the exact clock cycles needed. The 5us delay is a
test value and seems ok.
Without the delay, CCCR.CCE bit may fail to be set and then the initialization
fail sometimes when do repeatly up and down.
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The original code missed to set the cf->can_dlc in the RTR case, so add it.
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The M_CAN message RAM is usually equipped with a parity or ECC functionality.
But RAM cells suffer a hardware reset and can therefore hold arbitrary content
at startup - including parity and/or ECC bits.
To prevent the M_CAN controller detecting checksum errors when reading
potentially uninitialized TX message RAM content to transmit CAN frames the TX
message RAM has to be written with (any kind of) initial data.
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
m_can uses io memory which makes it not compilable on architectures
without HAS_IOMEM such as UML:
drivers/built-in.o: In function `m_can_plat_probe':
m_can.c:(.text+0x218cc5): undefined reference to `devm_ioremap_resource'
m_can.c:(.text+0x218df9): undefined reference to `devm_ioremap'
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The patch adds the basic CAN TX/RX function support for Bosch M_CAN controller.
For TX, only one dedicated tx buffer is used for sending data.
For RX, RXFIFO 0 is used for receiving data to avoid overflow.
Rx FIFO 1 and Rx Buffers are not used currently, as well as Tx Event FIFO.
Due to the message ram can be shared by multi m_can instances
and the fifo element is configurable which is SoC dependant,
the design is to parse the message ram related configuration data from device
tree rather than hardcode define it in driver which can make the message
ram sharing fully transparent to M_CAN controller driver,
then we can gain better driver maintainability and future features upgrade.
M_CAN also supports CANFD protocol features like data payload up to 64 bytes
and bitrate switch at runtime, however, this patch still does not add the
support for these features.
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Reviewed-by: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
[mkl: Squahed semicolon cleanup by Fengguang Wu]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>