Zephyr policy updates 20260727

[bentheredonethat]

Hi @zeddii -- there are spec updates so user can specify Domain YAML linker and MPU characteristics for Zephyr

Importantly, gen_domain_dts does not generate MPU permissions or linker scripts. It preserves the results produced by the dedicated assists.

Hi @sivadur @kedareswararao there are the gen-domain changes for:

• /scratch/blevinsk/lopper/lopper/assists/gen_domain_dts.py
• /scratch/blevinsk/lopper/lopper/assists/zephyr_supported_comp.yaml

It does the following:

• Preserves nodes explicitly marked with:

  compatible = "zephyr,memory-region";

• Preserves nodes referenced from /chosen, including:

  zephyr,sram = "...";
  zephyr,ipc_shm = "...";

• Prevents the generic Zephyr domain transformation from overwriting an already selected zephyr,sram.

• Renames R5/R52 memory nodes to match their processor-local reg addresses and updates /chosen references after the rename.

• Preserves these generated properties during pruning:

  zephyr,memory-region
  zephyr,memory-attr
  zephyr,sram

• Normalizes ZynqMP IPI mailbox properties for Zephyr:

  xlnx,ipi-id → local-ipi-id
  xlnx,ipi-id → remote-ipi-id
  reg-names = "host_ipi_reg"
  status = "okay"

• Removes incompatible properties from destination mailbox children where required.

• Extends the supported-compatible policy for:

  • zephyr,memory-region
  • mmio-sram
  • zephyr,mbox-ipm
  • vnd,mbox-consumer
  • xlnx,zynqmp-ipi-mailbox
  • xlnx,zynqmp-ipi-dest-mailbox

Intended execution order

Domain YAML
↓
YAML expansion
↓
zephyr-mpu
├── emits zephyr,memory-region
├── emits zephyr,memory-attr
└── selects /chosen/zephyr,sram
↓
zephyr-linker
├── writes the linker script
└── writes the layout report
↓
gen_domain_dts
├── prunes the domain
├── preserves generated Zephyr metadata
├── fixes local RPU memory names
└── produces the final Zephyr DTS

[zeddii]

I'm out of the office, back on Wednesday and will review these then.

[bentheredonethat]

@zeddii ok thank you!

[zeddii]

Thanks @bentheredonethat — this is well-structured and the split is right (linker/MPU in dedicated assists, gen_domain_dts only preserving the generated metadata). CI is green and the new tests target the tricky bits (sram-override guard, ipc_shm refs, RPU local-TCM range, linker expand +/-). A few items before it can be merged:

1. Rebase needed. #790 just merged, and it touches gen_domain_dts.py in the same areas this PR does — please rebase on latest master.

2. Rename may leave stale references to the renamed node. It looks to me like xlnx_zephyr_fixup_rpu_memory_names() only fixes /chosen refs for the hardcoded ("zephyr,sram",). A reference to a renamed node could be left pointing at the old path via:

• other /chosen entries (e.g. zephyr,ipc_shm) — _zephyr_node_must_be_preserved() scans all /chosen props;

• a &label/phandle reference from another node — the rename does delete → mutate abs_path/name → add, and add/delete don't re-register __symbols__/phandles on their own.

  To refresh after the rename: call sdt.tree.resolve() (re-resolves phandles/refs — the same call assemble_sdt.py uses after structural edits), and update the renamed node's /__symbols__ entry to the new path — there's already a precedent for exactly this in this file (the domain /__symbols__ fix-up, ~L655–668), followed by sdt.tree.sync(). A test that renames a node referenced by both zephyr,ipc_shm and a &label elsewhere, asserting both still resolve, would confirm it.

3. Guard the IPI id access. In xlnx_remove_unsupported_nodes(), node["xlnx,ipi-id"].value is read after matching xlnx,zynqmp-ipi-mailbox / -dest-mailbox — if a matching node lacks xlnx,ipi-id this throws KeyError. A cheap if node.props("xlnx,ipi-id") guard would harden it.

Minor (non-blocking): the rename uses reg[1] as the new unit-address, which assumes the high address cell is 0 (local TCM view) — fine for the intended case, worth a one-line comment.

With the rebase + items 2 and 3 addressed, this is good to go.

[bentheredonethat]

@zeddii rebased , updated , pushed!