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aseipp • yesterday at 12:22 PM • 2 replies • view on HN

Someone from Qualcomm posted a "DT-ACPI Hybrid Mode" set of patches a while back that let you call ACPI table functions, etc even while booting with the device tree, allowing you to control some things like keyboard lightning/power management independently. That would be a good first step but I'm not sure it went anywhere in the meantime. In theory supporting Device Tree by including the blob in a ROM somewhere shouldn't be much more work (if any) than including working ACPI tables, but we all know how that works out in practice!


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throwaway173738 • yesterday at 12:27 PM

> supporting Device Tree by including the blob in a ROM somewhere shouldn't be much more work (if any) than including working ACPI tables, but we all know how that works out in practice!

This is definitely a thing in some embedded systems I’ve used. There are some Marvell boards which do this. They all use U-boot though.

bigfishrunning • yesterday at 1:00 PM

The problem is that the content of the device tree isn't really stable -- if a new kernel version has a driver with a new required parameter for instance, suddenly your ROM device tree is out of date and much less useful.

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