On 16.07.2021 02:04:56, Joakim Zhang wrote:

quoted

On 15.07.2021 19:36:06, Dong Aisheng wrote:

quoted

Then should it be "fsl,imx8mp-flexcan", "fsl,imx8qxp-flexcan" rather
than only drop "fsl,imx6q-flexcan"?

The driver has compatibles for the 8qm, not for the 8qxp:

|	{ .compatible = "fsl,imx8qm-flexcan", .data =
&fsl_imx8qm_devtype_data, },
|	{ .compatible = "fsl,imx8mp-flexcan", .data =
|&fsl_imx8mp_devtype_data, },

AFAIK, we first design the i.MX8QM FlexCAN and later i.MX8QXP reuses
IP from i.MX8QM, so there is no difference for them.

IMHO, IP design is always backwards compatible,

Hopefully the IP blocks of the i.MX8Q* are compatible, but the other
flexcan IP core are not.

then we need list each as fallback compatible string? I think it's
unnecessary.

In the DTs we usually use the name of the SoC we're just describing as
the first compatible, and add a second compatible with the oldest SoC
having this IP core or an IP core that is compatible (so that the driver
works).

As the imx8mp needs the DISABLE_MECR quirk it's not compatible with the
imx6.

regards,
Marc

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