pylibfdt: expose address cells, size cells and memory reservation add/delete accessors - #190
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pylibfdt: expose address cells, size cells and memory reservation add/delete accessors#190alchark wants to merge 2 commits into
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Finding out how many cells a node's children use for addresses and sizes currently requires calling the raw fdt_address_cells()/fdt_size_cells() wrappers with the private FdtRo._fdt buffer, as the class exposes no methods for them. Add them to FdtRo alongside the other node accessors, and test them. Signed-off-by: Alexey Charkov <alchark@flipper.net>
The memory reserve map can be read through num_mem_rsv() and get_mem_rsv(), but changing it requires calling the raw fdt_* wrappers with the private Fdt._fdt buffer, as the class exposes no methods for the write side. Add them next to the existing accessors, and test them. Signed-off-by: Alexey Charkov <alchark@flipper.net>
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Merged, thanks (it will show as closed, not merged in github, because I merged via my private tree, not via github). |
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Finding out how many cells a node's children use for addresses and sizes currently requires calling the raw fdt_address_cells()/fdt_size_cells() wrappers with the private FdtRo._fdt buffer, as the class exposes no methods for them. Add them to FdtRo alongside the other node accessors. This is a local addition to the imported copy of pylibfdt, to be dropped on the next resync once it lands upstream. Link: dgibson/dtc#190 Signed-off-by: Alexey Charkov <alchark@flipper.net>
alchark
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The memory reserve map can be read through num_mem_rsv() and get_mem_rsv(), but changing it requires calling the raw fdt_* wrappers with the private Fdt._fdt buffer, as the class exposes no methods for the write side. Add them next to the existing accessors. This is a local addition to the imported copy of pylibfdt, to be dropped on the next resync once it lands upstream. Link: dgibson/dtc#190 Signed-off-by: Alexey Charkov <alchark@flipper.net>
alchark
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When a generated FIT is used to boot Linux directly, bypassing U-Boot proper (Falcon mode), there is no runtime code to discover the kernel command line and (optional) initrd location and include them in a FDT. To facilitate easier preparation of a ready-to-boot FIT, add support for pre-patching the FDTs in a FIT with a preconfigured /chosen node including the bootargs and initrd location. Note that the initrd part needs a pylibfdt providing address_cells() and add_mem_rsv(), which the in-tree copy does, but a system one only will once the respective pull request [1] lands and gets released. Link: dgibson/dtc#190 [1] Signed-off-by: Alexey Charkov <alchark@flipper.net>
alchark
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Aug 11, 2026
Finding out how many cells a node's children use for addresses and sizes currently requires calling the raw fdt_address_cells()/fdt_size_cells() wrappers with the private FdtRo._fdt buffer, as the class exposes no methods for them. Add them to FdtRo alongside the other node accessors. This is a local addition to the imported copy of pylibfdt, to be dropped on the next resync once it lands upstream. Link: dgibson/dtc#190 Signed-off-by: Alexey Charkov <alchark@flipper.net>
alchark
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that referenced
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Aug 11, 2026
The memory reserve map can be read through num_mem_rsv() and get_mem_rsv(), but changing it requires calling the raw fdt_* wrappers with the private Fdt._fdt buffer, as the class exposes no methods for the write side. Add them next to the existing accessors. This is a local addition to the imported copy of pylibfdt, to be dropped on the next resync once it lands upstream. Link: dgibson/dtc#190 Signed-off-by: Alexey Charkov <alchark@flipper.net>
alchark
added a commit
to flipperdevices/u-boot
that referenced
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Aug 11, 2026
When a generated FIT is used to boot Linux directly, bypassing U-Boot proper (Falcon mode), there is no runtime code to discover the kernel command line and (optional) initrd location and include them in a FDT. To facilitate easier preparation of a ready-to-boot FIT, add support for pre-patching the FDTs in a FIT with a preconfigured /chosen node including the bootargs and initrd location. Note that the initrd part needs a pylibfdt providing address_cells() and add_mem_rsv(), which the in-tree copy does, but a system one only will once the respective pull request [1] lands and gets released. Link: dgibson/dtc#190 [1] Signed-off-by: Alexey Charkov <alchark@flipper.net>
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Currently the access to address-cells/size cells requires poking into the FdtRo._fdt private buffer. Similarly, adding or deleting memory reservations requires poking into the Fdt._fdt private buffer.
This complicates things such as inserting a /chosen node with a pre-set kernel command line and initrd location/size properties into an existing device tree (as is required for preparing a device tree blob for booting with no runtime patching by a bootloader, e.g. using U-Boot's Falcon mode), so add public accessors for these.