Overlapping reg properties in imx6qdl.dtsi

[abdurrehman]

Hi,

We are trying to run different OS on different cores on sabrelite and we have a tool that partitions the resources in the device tree for these OSes.
This tool complains when there are nodes with overlapping memory regions.

e.g
At arch/arm/boot/dts/imx6qdl.dtsi there are multiple nodes that have overlapping reg properties.

Set 1:
mmdc0-1@021b0000 { /* MMDC0-1 */
compatible = “fsl,imx6q-mmdc-combine”;
};
mmdc0: mmdc@021b0000 { /* MMDC0 */
compatible = “fsl,imx6q-mmdc”;
};

Set 2:
caam_snvs: caam-snvs@020cc000 {
compatible = “fsl,imx6q-caam-snvs”;
};
snvs: snvs@020cc000 {
compatible = “fsl,sec-v4.0-mon”, “syscon”, “simple-mfd”;
};

Is this okay to have such overlaps? Do these overlaps in memory regions of different nodes in the dts indicate any problems with the DTS?

----------------
I asked this originally at https://boundarydevices.com/morty-yocto-release/#comment-376924 and was redirected here.

Thanks.

[Carlos_Musich · Accepted solution]

Hi Abdur,

On the DTS side there is not any problem on having multiple nodes pointing to the same memory regions. An example of this use case is having 2 different drivers configuring the same module for different functionality. You may consider these use cases in your tool to get rid of those warnings/errors.

I hope this helps.

Regards,
Carlos

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[gary_bisson]

Hi,

Just to help understanding what Adbur reports, please have a look at the NXP kernel tree imx6qdl.dtsi file:

linux-imx.git - i.MX Linux Kernel 

Regards,

Gary