dts: arm: nxp: RT10xx/11xx .dtsi Files: Remove flexram,bank-spec prop

[jacob-wienecke-nxp]

This commit removes the flexram,bank-spec property from dtsi files. The property causes flexram to be dynamically configured based on the configuration in flexram,bank-spec.

This is a problem for 2 reasons: 1) The FlexRAM will always be dynamically reconfigured to default fuse configuration. This is unnecessary if using default fuses. 2) If a user decides to program fuses. The FlexRAM will still be reconfigured to the default fuse configuration.

Modify description in the binding to show how to use the property at:
dts/bindings/memory-controllers/nxp,flexram.yaml

Added board overlay to mimxrt1170_evk_cm7 magic_addr:
samples/boards/nxp/mimxrt1170_evk_cm7/magic_addr/boards

[decsny]

Hey @jacob-wienecke-nxp, I have a question regarding this PR. I have manually resized my ITCM and DTCM regions on RT1061 to make my code and data fit in those internal TCMs, as @DerekSnell suggested me here, using the following configuration:

&itcm {
        reg = < 0x0 DT_SIZE_K(160) >;
};
&dtcm {
        reg = < 0x20000000 DT_SIZE_K(288) >;
};
&ocram {
        reg = < 0x20280000 DT_SIZE_K(64) >;
};
&flexram {
        flexram,bank-spec = <FLEXRAM_OCRAM>,
                            <FLEXRAM_OCRAM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_DTCM>,
                            <FLEXRAM_ITCM>,
                            <FLEXRAM_ITCM>,
                            <FLEXRAM_ITCM>,
                            <FLEXRAM_ITCM>,
                            <FLEXRAM_ITCM>;
};

So my question is after the merge of this PR, how this resize should be facilitated ?

Thanks.

The PR doesn't remove the property from the binding, just the property usage from the SOC DTSI files, so you don't need to change anything

[decsny]

change request: add description to DT binding for flexram about how to use it

also, maybe add an overlay to the magic-addr sample to have CI for at least one example of dynamic reconfigure in tree, otherwise we have no CI coverage of this feature at all

[decsny]

@kartben is it possible we can still add this to 4.1 without TSC approval (once it gets the approvals)?

It's not fixing a bug, but it's:

• improving the documentation of the binding
• reducing the usage of this feature in the tree, so that it is not used by default (the platform boot is significantly more robust if this feature is not enabled, because then it relies on the chip metal ROM instead of the zephyr image to configure RAM banks)
• Adding an overlay to a relevant sample so CI still covers the feature

[kartben]

It actually sounds to me like it's fixing a bug—point #2 in the PR description—with #1 also being something that could be considered a bug (unnecessary code being pulled in / executed) so fine with me!

cc @fabiobaltieri