IDE in Mode 1 (Sandpoint) how ?

IDE in Mode 1 (Sandpoint) how ?

[Sarnath Kannan]

hi all,
The Sandpoint user's manual says that WinBond's IDE controller is disabled in mode 1 (s3-down, s4-up), but MontaVista's kernel works in mode 1 with IDE support!
How is this possible ?
 Moreover, the kernel we had built ( not from mVista) runs too too slow. ( altho linux comes up ). The kernel
boots fine and fast but once INIT comes up,
systems slows down like crazy..( unagreeable
speed ). This looks very tantalizing.

Thanx for any help
Sarnath


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Re: IDE in Mode 1 (Sandpoint) how ?

[Dan Malek]

Sarnath Kannan wrote:

> hi all,
> The Sandpoint user's manual says that WinBond's IDE controller is disabled in mode 1 (s3-down, s4-up), but MontaVista's kernel works in mode 1 with IDE support!
> How is this possible ?

The up/down comment is relative to the installation of the board in the chassis.
Mine are actually the other way around.  I'm not even sure if on/off nomenclature
would work.

>  Moreover, the kernel we had built ( not from mVista) runs too too slow.

Sounds like you have the switches in the wrong position and the interrupts
are not routed correctly.  The serial port will eventually time out when it
doesn't receive interrupts, giving the perception of a very slow running system.

Just keep in mind the troubles are local to your configuration, as this software
operates fine on a properly configured board.  Just move switches until it works,
then leave them alone :-).


	-- Dan


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Re: IDE in Mode 1 (Sandpoint) how ?

[Mark A. Greer]

Dan Malek wrote:

> Sarnath Kannan wrote:
>
> > hi all,
> > The Sandpoint user's manual says that WinBond's IDE controller is disabled in mode 1 (s3-down, s4-up), but MontaVista's kernel works in mode 1 with IDE support!
> > How is this possible ?

Because the documentation is misleading...

> The up/down comment is relative to the installation of the board in the chassis.
> Mine are actually the other way around.  I'm not even sure if on/off nomenclature
> would work.

Sarnath, Dan is completely correct, it is relative so you need to first *carefully read* the comments in sandpoint_setup.c that describe the switch setting,
*understand them*, and then *follow them*.   Especially the part where it says:


     " * 'down' is in the direction from the PCI slots towards the PPMC slot;
      * 'up' is in the direction from the PPMC slot towards the PCI slots.
      * Be careful, the way the sandpoint board is installed in XT chasses will
      * make the directions reversed."

> Just keep in mind the troubles are local to your configuration, as this software
> operates fine on a properly configured board.  Just move switches until it works,
> then leave them alone :-).

ditto


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Re: Re: IDE in Mode 1 (Sandpoint) how ?

[Sarnath Kannan]

Hi,
> Sounds like you have the switches in the wrong position
> and the interrupts
> are not routed correctly.  The serial port will
> eventually time out when it
> doesn't receive interrupts, giving the perception of a
> very slow running system.
>
> Just keep in mind the troubles are local to your
> configuration, as this software
> operates fine on a properly configured board.  Just
> move switches until it works,
> then leave them alone :-).

  Ur suggestion is acceptable. But whatss troubling
my head is, the kernel boots up fine until the NFS mount.
Had the switch settings been wrong, the serial output
would be slow from early bootup, right ?  But thats
not the case. Why should it be slow after INIT starts
up ?
 Meanwhile, I am also trying the same with different
switch settings.

Thanks
Sarnath


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Re: IDE in Mode 1 (Sandpoint) how ?

[Dan Malek]

Sarnath Kannan wrote:


> ..... But whatss troubling
> my head is, the kernel boots up fine until the NFS mount.
> Had the switch settings been wrong, the serial output
> would be slow from early bootup, right ?

Nope.  All of the kernel print out is polled I/O.

> .....  But thats
> not the case. Why should it be slow after INIT starts
> up ?

Because it uses interrupt driven serial I/O.

Believe me, all of us using Sandpoints have seen this before.
Your interrupt/arbitration routing switches on the board are wrong.


	-- Dan


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Re: Re: IDE in Mode 1 (Sandpoint) how ?

[Sarnath Kannan]

hi Dan,

> Nope.  All of the kernel print out is polled I/O.
>
  yeah ! Thats right.

>me: .....  But thats
>me: not the case. Why should it be slow after INIT
>me:starts
>me: up ?
>
> Because it uses interrupt driven serial I/O.

  I'am currently investigating that code path, Dan.
  We have also come to the same conclusion as u.
  But believe me, I had tried with all possible
  Switch settings, S3,S4,S5,S6. :-( Its tantalising !
  This means that all ISA interrupts are not
  being routed properly. One more, I haven't
  initialized the WinBond, coz reset values seem
  meaninful. Could that be the reason for
  this ?
>
> Believe me, all of us using Sandpoints have seen this
> before.
> Your interrupt/arbitration routing switches on the
> board are wrong.

  Any suggestion from experienced people is welcome.


Is there any other switch, other than the S3,S4,S5,S6
I need to worry about.

sarnath


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Re: IDE in Mode 1 (Sandpoint) how ?

[Dan Malek]

Sarnath Kannan wrote:


>   This means that all ISA interrupts are not
>   being routed properly. One more, I haven't
>   initialized the WinBond, coz reset values seem
>   meaninful. Could that be the reason for
>   this ?

Between the boot rom and Linux, the Winbond part is initialized
properly.  If you haven't removed any code, it should be fine.


> Is there any other switch, other than the S3,S4,S5,S6
> I need to worry about.

I forgot, is this an X2 or X3 (or X3b) version of the Sandpoint?


	-- Dan


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