On Jan 14 19:10:32, kolip...@exoticsilicon.com wrote:
> On Fri, Jan 14, 2022 at 10:41:52PM +0100, Jan Stary wrote:
> > I suspect it's com1; I have yet to try commenting out just tty01.
> > But commenting out both makes it boot OK.
> >
> > com0 at acpi0 COMA addr 0x3f8/0x8 irq 4: ns16550a, 16 byte fifo
> > com1 at acpi0 COMB addr 0x2f8/0x8 irq 3: ti16750, 64 byte fifo
> >
> > Are these known to misbehave under ttyflags?
> >
> > I realize a lot has changed since then, but it's a production machine,
> > and while I would love nothing more than go through the releases one
> > by one, this machine has to run now.
>
> Well there were recently changes to make com attach via acpi, and now
> you have a com port that you didn't have before.
This is to confirm that the "new" com1 @ acpi is the culprit:
it is enough to comment out tty01 in /etc/ttys
and the boot gets through ttyflags -a
> My suspicion would be that the new com1 either does not really exist in
> hardware, or that it's mis-configured.
Please excuse my HW ignorance: does "ti16750" mean then
that some ACPI table _says_ there it a (Texas Instruments?) com,
even if there isn't really? At any rate, there is just one
visible cereal on the PowerEdge's case.
> Does the BIOS mention it? Can it be disabled there?
The BIOS only mentions "Serial port 1 ... COM1",
which I suppose is 1-based indexing, so that's com0 aka tty00.
There is no other serial port in the BIOS to be disabled.
(Got a diff in the meantime, recompiling now.)
Jan
