topic Re: iMX6 FLEXCAN Hardware filter with mailbox implementation for Android KK in i.MX Processors

iMX6 FLEXCAN Hardware filter with mailbox implementation for Android KK

sudarkb — Wed, 17 Jan 2024 11:46:50 GMT

Dear All,

We are currently using iMX6 Solo based carrier board design running Android KK (Linux kernel 3.0.35). We are trying to set the CAN hardware filters to filter out the unwanted CAN messages. We have done the mailbox implementation in the 3.0.35 kernel. The below registers are set to accept CAN messages with odd number IDs.

for (i = 0; i < ARRAY_SIZE(regs->mb); i++)
flexcan_write((0x01), &regs->rximr[i]);

The maximum number of mailbox set is 64. Kindly, let me know if we are missing out anything for configuring the hardware filter. Also, there will be standard CAN ID in our use case and we don't use any extended CAN ID messages.

Regards,
Sudar

Re: iMX6 FLEXCAN Hardware filter with mailbox implementation for Android KK

AldoG — Mon, 22 Jan 2024 19:51:08 GMT

Hello,

Unfortunately as you're working with a rather old kernel version it would be very difficult to provide support.

I could suggest to take a look to the CAN driver documentation to use it as reference:
https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/Documentation/networking/can.rst#can-filter-usage-optimisation

Best regards/Saludos,
Aldo.

Re: iMX6 FLEXCAN Hardware filter with mailbox implementation for Android KK

sudarkb — Thu, 25 Jan 2024 17:05:33 GMT

Hi Aldo,

Thanks for the response.

The content of link seems to set the CAN software filters using the netlink layer. We would like to know if the latest drivers have the implementation to configure the hardware filters? or its not currently supported? Our customer would like to set the hardware filters for their use case. Kindly, let us know if any specific FLEXCAN registers that needs to be configured for its working.

Regards,
Sudar

Re: iMX6 FLEXCAN Hardware filter with mailbox implementation for Android KK

AldoG — Tue, 30 Jan 2024 20:52:52 GMT

Hello,

You may look at this one as well:
https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/Documentation/networking/can.rst#raw-socket-option-can_raw_filter

Best regards,
Aldo.