Re: 2.6.24: Serial disabled in BIOS but serial modules still loaded (probably PnP related)

[Yinghai Lu]

On Nov 24, 2007 12:36 PM, Andrey Borzenkov <arvidjaar@xxxxxxx> wrote:
> I have no COM port on notebook (without port replicator which I do not have)
> so COM is disabled in BIOS. No ttyS* is detected during boot (and no device
> created) but I just noticed that serial modules are still loaded. Well, this
> partially defeats the purpose of disabling COM port - the intention was to
> free resources by *not* loading unneeded modules ...
>
> This may have something to do with (ACPI) PnP which apparently believes COM is alive.
> Notebook is Toshiba Portege 4000.
>
> {pts/0}% lsmod | grep 82
> 8250_pnp                9792  0
> 8250                   24660  1 8250_pnp
> serial_core            22872  1 8250
>
> {pts/0}% lspnp -v
> 00:00 PNP0c01 System board
>     state = active
>         mem 0x0-0x9ffff
>         mem 0xe0000-0xeffff
>         mem 0xf0000-0xfffff
>         mem 0x100000-0x1ef5ffff
>
> 00:01 PNP0a03 PCI bus
>     state = active
>         io 0xcf8-0xcff
>
> 00:02 PNP0200 AT DMA controller
>     state = active
>         io 0x0-0xf
>         io 0x81-0x83
>         io 0x87-0x87
>         io 0x89-0x8b
>         io 0x8f-0x8f
>         io 0xc0-0xdf
>         dma 4
>
> 00:03 PNP0800 AT speaker
>     state = active
>         io 0x61-0x61
>
> 00:04 PNP0c04 Math coprocessor
>     state = active
>         io 0xf0-0xff
>         irq 13
>
> 00:05 PNP0303 IBM enhanced keyboard (101/102-key, PS/2 mouse support)
>     state = active
>         io 0x60-0x60
>         io 0x64-0x64
>         irq 1
>
> 00:06 PNP0f13 PS/2 port for PS/2-style mice
>     state = active
>         irq 12
>
> 00:07 PNP0b00 AT real-time clock
>     state = active
>         io 0x70-0x71
>         irq 8
>
> 00:08 PNP0c02 Motherboard resources
>     state = active
>         io 0x2e-0x2f
>         io 0x62-0x62
>         io 0x66-0x66
>         io 0x80-0x80
>         io 0x84-0x86
>         io 0x88-0x88
>         io 0x8c-0x8e
>         io 0x92-0x92
>
> 00:09 PNP0501 16550A-compatible serial port
>     state = active
>         io 0x3f8-0x3ff
>         irq 5
>
> 00:0a SMCf010 SMC Fast Infrared Port
>     state = disabled
>
> 00:0b PNP0401 ECP printer port
>     state = disabled
>
> ..
> [  126.035809] Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled
...
> [  126.107096] serial 00:09: activated
...

Can you cat /sys/firmware/acpi/DSDT and use iasl to decode it?
it seems that your BIOS has problem about com setup.

YH
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