On 03/01/2016 10:34 AM, Ramesh Shanmugasundaram wrote:

This patch adds support for the CAN FD controller found in Renesas R-Car
SoCs. The controller operates in CAN FD mode by default. Two test modes
are available and can be enabled by the "rcar_canfd.testmode" module
parameter. Refer to Documentation/kernel-parameters.txt.

Is the channel loopback mode configurable per channel? If so, please
remove the module parameter and make use of CAN_CTRLMODE_LOOPBACK to
configure it.

CAN FD mode supports both Classical CAN & CAN FD frame formats. The
controller supports ISO 11898-1:2015 CAN FD format only.

This controller supports two channels and the driver can enable either
or both of the channels.

Driver uses Rx FIFOs (one per channel) for reception & Common FIFOs (one
per channel) for transmission. Rx filter rules are configured to the
minimum (one per channel) and it accepts Standard, Extended, Data &
Remote Frame combinations.

I see no locking for the tx-path.

Note: There are few documentation errors in R-Car Gen3 Hardware User
Manual v0.5E with respect to CAN FD controller. They are listed below:

1. CAN FD interrupt numbers 29 & 30 are listed as per channel
interrupts. However, they are common to both channels (i.e.) they are
global and channel interrupts respectively.

2. CANFD clock is derived from PLL1. This is not documented.

3. CANFD clock is further divided by (1/2) within the CAN FD controller.
This is not documented.

4. The minimum value of NTSEG1 in RSCFDnCFDCmNCFG register is 2 Tq. It
is mentioned 4 Tq in the manual.

5. The maximum number of message RAM area the controller can use is 3584
bytes. It is mentioned 10752 bytes in the manual.

Signed-off-by: Ramesh Shanmugasundaram <redacted>

Marc

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