[Xenomai-help] Xenomai Ready PC

[Xenomai-help] Xenomai Ready PC

[Adrian Boeing]

Hi,

We require an industrial PC with CAN, and want to run Xenomai on it.

Are there any vendors who already sell a complete PC package with
Xenomai & CAN drivers pre-loaded?
(I have seen that Peak Systems sell a CAN card with Xenomai drivers,
but does anyone sell a complete package?)

We have been having some difficulty getting Xenomai/Linux working on
some industrial PCs.

Thanks,
-Adrian

Re: [Xenomai-help] Xenomai Ready PC

[Gilles Chanteperdrix]

Adrian Boeing wrote:
> Hi,
> 
> We require an industrial PC with CAN, and want to run Xenomai on it.
> 
> Are there any vendors who already sell a complete PC package with
> Xenomai & CAN drivers pre-loaded?
> (I have seen that Peak Systems sell a CAN card with Xenomai drivers,
> but does anyone sell a complete package?)
> 
> We have been having some difficulty getting Xenomai/Linux working on
> some industrial PCs.

What kind of difficulty? Maybe we could try and solve it?

-- 
					    Gilles.

Re: [Xenomai-help] Xenomai Ready PC

[Gilles Chanteperdrix]

Adrian Boeing wrote:
> We are having trouble just getting the PC to install linux (it fails
> to install, and if we install on another machine, and bring the HDD
> across then it boots very very slowly), we also have to write our own
> Xenomai CAN drivers.

So your problem seems rather to be with Linux than with Xenomai? Or did
you recompile the kernel?

As far as I know, a distribution with a non working kernel for your PC
can nevertheless be installed on the PC provided that you change the
kernel used for installation, and use that same kernel once the
distribution installed. Slow boot probably means that the kernel is
using the wrong drivers for the disk. That is because upon first
installation, the initrd/initramfs that is build and will be used for
next boots is specific to your disk controller. This can be fixed after
the slow boot by rerunning mkinitrd/mkinitramfs/whatever your
distribution provides to re-adapt the initrd/initramfs to your disk
controller. But you can avoid this issue completely by building a kernel
tailored to your PC without even the need for an initrd/initramfs.

Of course, if your chipset/disk controller is not even recognized by
recent kernels, you are toast. But that should be the exception, not the
rule.

> 
> We would strongly prefer to purchase a complete system that is known
> to work with Xenomai.

I do not know if such a thing exist. The problems to avoid (specific to
Xenomai I mean), if that is an x86, are:
- check that there is no SMI issue, or if there is, that the SMI can be
safely disabled (that is that they can be disabled at all, and that
disabling them does not cause issues such as overheating);
- check that there is no IRQ sharing between real-time drivers (such as
RT-can) and other peripherals on your board. If that happens, you may be
able to fix it by swapping PCI cards, and/or using BIOS to disable
integrated peripherals, or disable them in the kernel configuration.


-- 
                                          Gilles

Re: [Xenomai-help] Xenomai Ready PC

[Adrian Boeing]

Hi Wolfgang & Gilles,

Thanks for the list of Xenomai-supported PCI cards:

034 config XENO_DRIVERS_CAN_SJA1000_IXXAT_PCI
039         This driver is for the IXXAT PC-I 04/PCI card (1 or 2 channel)
040         from the IXXAT Automation GmbH (http://www.ixxat.de). To get
041         the second channel working, Xenomai's shared interrupt support
042         must be enabled

Exactly which card is this?
(IXXAT has a list here:
http://www.ixxat.de/overview-pc-can-interface-board_de.html)
Is it the iPC-I 320/PCI II?

The problem with the PC seems to be with Linux, I'll try the disk
driver reinitialization Gilles suggested.

Thanks,
-Adrian

On Wed, Dec 2, 2009 at 6:18 PM, Gilles Chanteperdrix
<gilles.chanteperdrix@xenomai.org> wrote:
> Adrian Boeing wrote:
>> We are having trouble just getting the PC to install linux (it fails
>> to install, and if we install on another machine, and bring the HDD
>> across then it boots very very slowly), we also have to write our own
>> Xenomai CAN drivers.
>
> So your problem seems rather to be with Linux than with Xenomai? Or did
> you recompile the kernel?
>
> As far as I know, a distribution with a non working kernel for your PC
> can nevertheless be installed on the PC provided that you change the
> kernel used for installation, and use that same kernel once the
> distribution installed. Slow boot probably means that the kernel is
> using the wrong drivers for the disk. That is because upon first
> installation, the initrd/initramfs that is build and will be used for
> next boots is specific to your disk controller. This can be fixed after
> the slow boot by rerunning mkinitrd/mkinitramfs/whatever your
> distribution provides to re-adapt the initrd/initramfs to your disk
> controller. But you can avoid this issue completely by building a kernel
> tailored to your PC without even the need for an initrd/initramfs.
>
> Of course, if your chipset/disk controller is not even recognized by
> recent kernels, you are toast. But that should be the exception, not the
> rule.
>
>>
>> We would strongly prefer to purchase a complete system that is known
>> to work with Xenomai.
>
> I do not know if such a thing exist. The problems to avoid (specific to
> Xenomai I mean), if that is an x86, are:
> - check that there is no SMI issue, or if there is, that the SMI can be
> safely disabled (that is that they can be disabled at all, and that
> disabling them does not cause issues such as overheating);
> - check that there is no IRQ sharing between real-time drivers (such as
> RT-can) and other peripherals on your board. If that happens, you may be
> able to fix it by swapping PCI cards, and/or using BIOS to disable
> integrated peripherals, or disable them in the kernel configuration.
>
>
> --
>                                          Gilles
>
>

Re: [Xenomai-help] Xenomai Ready PC

[Wolfgang Grandegger]

Adrian Boeing wrote:
> Hi Wolfgang & Gilles,
> 
> Thanks for the list of Xenomai-supported PCI cards:
> 
> 034 config XENO_DRIVERS_CAN_SJA1000_IXXAT_PCI
> 039         This driver is for the IXXAT PC-I 04/PCI card (1 or 2 channel)
> 040         from the IXXAT Automation GmbH (http://www.ixxat.de). To get
> 041         the second channel working, Xenomai's shared interrupt support
> 042         must be enabled
> 
> Exactly which card is this?
> (IXXAT has a list here:
> http://www.ixxat.de/overview-pc-can-interface-board_de.html)
> Is it the iPC-I 320/PCI II?

No, it's just for the passive CAN hardware, PC-I 04/PCI. Active hardware
does not allow to access the SJA1000 directly.

Wolfgang.

Re: [Xenomai-help] Xenomai Ready PC

[Wolfgang Grandegger]

Hi Adrian,

Adrian Boeing wrote:
> Hi,
> 
> We require an industrial PC with CAN, and want to run Xenomai on it.
> 
> Are there any vendors who already sell a complete PC package with
> Xenomai & CAN drivers pre-loaded?
> (I have seen that Peak Systems sell a CAN card with Xenomai drivers,
> but does anyone sell a complete package?)
> 
> We have been having some difficulty getting Xenomai/Linux working on
> some industrial PCs.

There are "good" and "bad" PC for real-time (with Xenomai), I know.
Unfortunately, I can not give valuable recommendations. But for CAN with
Xenomai you should use RT-Socket-CAN, which supports various SJA1000
based CAN cards. A (x)PCI card is preferred. See:

http://www.rts.uni-hannover.de/xenomai/lxr/source/ksrc/drivers/can/sja1000/Kconfig

Wolfgang.