Confused about 2.6 PnP support

Confused about 2.6 PnP support

[DervishD]

    Hi all :)

    I'm on the way of upgrading to 2.6.x kernel, and since I don't
have ISA cards (I don't even have an ISA bus in my mobo), I disabled
ISA support in my config (CONFIG_ISA), but I've noticed that PnP
support (CONFIG_PNP) depends on it :?

    AFAIK, PnP, strictly speaking, has nothing to do with the PCI
bus, but I think is common notation to talk about PnP referring
autoconfiguration of PCI cards, and I want to know if I need to
select PCI support for having my PCI cards correctly detected and
configured (currently my BIOS does the work), or if the PnP support
in kernel 2.6 is just for ISA cards. In addition to this, the PnP
BIOS support (which I think I may need so Linux correctly gets the
IO, IRQ and DMA settings for my parallel port) is marked as
EXPERIMENTAL (at least in 2.6.5)

    I want to know if I must tell my BIOS I don't have a PnP OS or
if, on the contrary, I should tell my BIOS that my OS is not PnP (I
only use Linux) and deselect PnP support (as well as ISA support) in
my 2.6.x kernel. Personally, I don't mind setting 'Non PnP OS' in my
BIOS and remove both CONFIG_ISA and CONFIG_PNP.

    BTW, ¿does Linux support rebalancing of PnP bus resources or I
better avoid conflicts...?

    Thanks a lot in advance :)

    Raúl Núñez de Arenas Coronado

-- 
Linux Registered User 88736
http://www.pleyades.net & http://raul.pleyades.net/

Re: Confused about 2.6 PnP support

[Adam Belay]

On Mon, Apr 12, 2004 at 07:05:15PM +0200, DervishD wrote:
>     Hi all :)
> 
>     I'm on the way of upgrading to 2.6.x kernel, and since I don't
> have ISA cards (I don't even have an ISA bus in my mobo), I disabled
> ISA support in my config (CONFIG_ISA), but I've noticed that PnP
> support (CONFIG_PNP) depends on it :?
> 
>     AFAIK, PnP, strictly speaking, has nothing to do with the PCI
> bus, but I think is common notation to talk about PnP referring
> autoconfiguration of PCI cards, and I want to know if I need to
> select PCI support for having my PCI cards correctly detected and
> configured (currently my BIOS does the work), or if the PnP support
> in kernel 2.6 is just for ISA cards. In addition to this, the PnP
> BIOS support (which I think I may need so Linux correctly gets the
> IO, IRQ and DMA settings for my parallel port) is marked as
> EXPERIMENTAL (at least in 2.6.5)

In this context PnP is refering to configuration of system and ISA
devices.  PnPBIOS support should be safe but faults on boot for a few
buggy systems.  Because the recovery code has been fixed, this should
be less of a problem.  If you see a message indicating that a pnp
device was activated as the parport driver loads then you need PnPBIOS
support to properly use it.  If not, then PnPBIOS will still aid in the
device's detection process.

>
>     I want to know if I must tell my BIOS I don't have a PnP OS or
> if, on the contrary, I should tell my BIOS that my OS is not PnP (I
> only use Linux) and deselect PnP support (as well as ISA support) in
> my 2.6.x kernel. Personally, I don't mind setting 'Non PnP OS' in my
> BIOS and remove both CONFIG_ISA and CONFIG_PNP.

If you are using PnPBIOS support then set PNP OS to "yes", otherwise use
"no".

>
>     BTW, ?does Linux support rebalancing of PnP bus resources or I
> better avoid conflicts...?

Yes, see sysfs and drivers/pnp/interface.c.  Resources can be reallocated
but only if the device is not bound to a driver (modules are useful for this).

>
>     Thanks a lot in advance :)
>
>     Ra?l N??ez de Arenas Coronado
>

Regards,
Adam

Re: Confused about 2.6 PnP support

[DervishD]

    Hi Adam, and thanks for your answer :)

 * Adam Belay <ambx1@neo.rr.com> dixit:
> >     AFAIK, PnP, strictly speaking, has nothing to do with the PCI
> > bus, but I think is common notation to talk about PnP referring
> > autoconfiguration of PCI cards, and I want to know if I need to
> > select PCI support for having my PCI cards correctly detected and
> > configured (currently my BIOS does the work), or if the PnP support
> > in kernel 2.6 is just for ISA cards. In addition to this, the PnP
> > BIOS support (which I think I may need so Linux correctly gets the
> > IO, IRQ and DMA settings for my parallel port) is marked as
> > EXPERIMENTAL (at least in 2.6.5)
> In this context PnP is refering to configuration of system and ISA
> devices.

    But then, why it depends on ISA support?

    BTW, in the case of my printer, the log says:

parport0: PC-style at 0x378 (0x778), irq 7 [PCSPP,TRISTATE]
lp0: using parport0 (interrupt-driven).
lp0: console ready

    The question is that my parallel port is configured as EPP, using
DMA 3, not as SPP, and I'm not sure if the problem is on the kernel,
the motherboard or if it is a simple matter of notation and the port
is being properly detected. My /proc/sys/dev/parport says
PCSPP,TRISTATE, not EPP... But DMA channel, IRQ line and IO addresses
are being correctly detected, so this doesn't seem a problem of PnP.

> >     I want to know if I must tell my BIOS I don't have a PnP OS or
> > if, on the contrary, I should tell my BIOS that my OS is not PnP (I
> > only use Linux) and deselect PnP support (as well as ISA support) in
> > my 2.6.x kernel. Personally, I don't mind setting 'Non PnP OS' in my
> > BIOS and remove both CONFIG_ISA and CONFIG_PNP.
> If you are using PnPBIOS support then set PNP OS to "yes", otherwise use
> "no".

    So if I don't want ISA support in my kernel I must go with PNP OS
set to 'no' and let the BIOS do the work, am I right?
 
> >     BTW, ?does Linux support rebalancing of PnP bus resources or I
> > better avoid conflicts...?
> Yes, see sysfs and drivers/pnp/interface.c.  Resources can be
> reallocated but only if the device is not bound to a driver
> (modules are useful for this).

    Cool :)) Thanks for the information.

    Raúl Núñez de Arenas Coronado

-- 
Linux Registered User 88736
http://www.pleyades.net & http://raul.pleyades.net/