Grub doesn’t load devicetree

[Tomaž Zaman]

I’m working on an arm64 board with an NXP LS1046A CPU and I simply cannot get Grub to load a different device tree than the one that’s provided to it by the EFI Stub.

=> fatload mmc 0:1 $kernel_addr_r /EFI/boot/grubaa64.efi
=> fatload mmc 0:1 $fdt_addr_r /boot/dtb/fsl-ls1046a-rdb-sdk.dtb
=> bootefi $kernel_addr_r $fdt_addr_r

At his point, I get a couple of errors like “smmu node not found”.

However, if I, instead of "fsl-ls1046a-rdb-sdk.dtb” use "fsl-ls1046a-rdb.dtb”, then I get to Grub without any errors.

And this is where I encounter the issue. Because I would like to use a different DTB for booting Linux than the one that’s provided by the EFI configuration table, I set

devicetree /boot/dtb/fsl-ls1046a-rdb-sdk.dtb
linux /boot/vmlinuz-6.6.3-arm64
initrd /boot/initrd.img-6.6.3-arm64

In this case, the devicetree instruction gets ignored completely, and before I see kernel loading, the message “Using FDT from the EFI configuration table"

Is there a way for me to override/replace the device tree that u-boot passed to Grub? I tried passing the “dtb=“ parameter to the kernel boot command, but in that case, I get "EFI stub: ERROR: Failed to handle fs_proto” because kernel when booting doesn’t appear to have access to the same filesystem that Grub does.

Thank you!


(this is my first time using *any* mailing list, so apologies if this is the wrong address to send this question to)

Tomaž Zaman, CEO
Mono Technologies Inc.
+386 30 651 645

[cid:18EB2FEE485A4DD7A1CE716CE14FCBC7]

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