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ACPI FADT reports missing 8042 keyboard under qemu
Posted: Thu Sep 29, 2016 4:48 am
by stdcall
Hi.
I started working on keyboard driver, and for starters I would like to detect the existance using ACPI FADT table.
It appears that the 8042 flag is marked as 0 - missing.
I'm using qemu-system-i386 for testing, with no specific configuration. is the problem is in qemu configuration ?
Re: ACPI FADT reports missing 8042 keyboard under qemu
Posted: Thu Sep 29, 2016 4:54 am
by thepowersgang
Have you checked that that field is valid in that table? If the table is of an earlier version, the field should be assumed to be "true"
Re: ACPI FADT reports missing 8042 keyboard under qemu
Posted: Thu Sep 29, 2016 5:35 am
by stdcall
According to ACPI documentation, the 8042 is valid since V2. however I didn't find any reference in the FADT table to the current table version.
Where does the FADT version is written ?
Re: ACPI FADT reports missing 8042 keyboard under qemu
Posted: Thu Sep 29, 2016 5:37 am
by stdcall
Found it. silly me.
Re: ACPI FADT reports missing 8042 keyboard under qemu
Posted: Thu Sep 29, 2016 5:42 am
by stdcall
That was indeed the problem. FADT is version 1.
How come it's so old ? FADT is now at version 5. Qemu doesn't support later versions ?
Re: ACPI FADT reports missing 8042 keyboard under qemu
Posted: Thu Sep 29, 2016 7:45 am
by thepowersgang
It doesn't need to - All the information qemu needs to provide is within the v1 structure - so it's a waste of space to provide the larger versions.