sio0: port may not be enabled
xfb52 at dial.pipex.com
Sat Apr 21 11:49:58 UTC 2007
Marcel Moolenaar wrote:
> On Apr 20, 2007, at 8:23 AM, Jeremy Chadwick wrote:
>> Look closely at the dmesg line, note what device sio0 is claiming to be
>> associated with (acpi0, not isa0):
>>> sio0: <16550A-compatible COM port> port 0x3f8-0x3ff irq 4 flags
>>> 0x10 on acpi0
>> This is one of the drawbacks to using ACPI.
> Could you try uart(4) instead. It seems quite excessive to have to
> disable ACPI just to get a serial port working. I'd like to know
> if this is related to the sio(4) driver or something else.
Just a note that I get exactly the same issues with my BIOS/ACPI but *my
serial port works*. I have not needed to disable ACPI nor to use
uart(4). The sio0 line has an IRQ associated with it (4) and I think if
there were really a problem there would be no IRQ here.
IIRC, the issue is something to do with ACPI presenting the serial ports
backwards wrt the BIOS. I know I got concerned about this when I first
encountered it, and tried stuff to swap the two ports I have over, but
nothing I did made the initial "ACPI probed irqs" error go away so I
just tried the serial port and it worked.
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