alpm(4) I/O range is claimed by ACPI

Bruce M Simpson bms at
Sun Sep 14 14:14:47 UTC 2008

John Baldwin wrote:
>> But surely if alpm(4) were to attach to such a range in this way, it
>> would need to be a child of the acpi bus device, yes?
> No, the code in acpi_alloc_resources() does _not_ check for that.  Any child 
> device with a specific allocation that falls in a system resource range will 
> succeed the allocation.

Ah, it is clearer after looking at devinfo output. Allocations will 
bubble up the bus drivers until they get to nexus. In this case, acpi is 
a child of nexus, therefore it will satisfy the allocation.

>> It looks like there used to be a means of doing this in the FreeBSD
>> driver but it got nuked. And that ASUS didn't much care about power
>> management support in this machine...
> If you can re-enable it in such a way that it uses bus_alloc_resource(), then 
> the driver will probably work fine.

In that case it sounds like one needs to be able to use a hard-wired 
hint. It has been over a year since I've been able to do any proper work 
on mips , which needs a lot of this sort of thing, and I don't have a 
compelling case to do it now, so hopefully someone with an interest can 
pick this up.


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