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Hello,

I am reading the acpi (5a) specification.

If I get the DSDT table and the purpose of a SSDT table, which is to complement a DSDT table, I am not sure if the SSDT should be placed right after its DSDT.

A SSDT can only rely on the DSDT being loaded prior to it.

Is prior just timely based (SSDT coming after but at a random memory position the DSDT) or time and space based (SSDT coming right after the DSDT in memory)?

If the first, I should check the ID of the device/maker. If second, no need, we can deduce it from the last DSDT.

Maybe I got something wrong, and overlooked something.

Thanks for your help,

Hi,

JulienDarc wrote:Is prior just timely based (SSDT coming after but at a random memory position the DSDT) or time and space based (SSDT coming right after the DSDT in memory)?

If the first, I should check the ID of the device/maker. If second, no need, we can deduce it from the last DSDT.

Maybe I got something wrong, and overlooked something.

You'd search the list of ACPI tables looking for the DSDT and use it to populate an initial "AML namespace"; then you'd search the list of ACPI tables looking for any SSDTs and merge them into your "AML namespace".

It shouldn't matter much where any of the tables are in memory; you still have to search anyway.


Cheers,

Brendan

Bingo,

Thanks Brendan