ITCO v4 support

[Arturs Laizans]

Hello List!

I am looking forward to implementing support for ITCO version 4. We need it for Intel Kaby Lake U processor (Celeron 3965U) equipd with Sunrise Point-LP SMBus (PCI device ID 0x9D23).

I have no prior experience with this. Are there any tips or heads up advice I should consider?

Best Regards,
Arturs Laizans

[Jan Kiszka]

There are two major steps here:
1. detect the LPC PCI device of your board in itco.c (iTCO_chipset_info)
2. take the needed actions for ITCO_V4, deriving it from the kernel's
drivers/watchdog/iTCO_wdt.c

There are not many places where itco_version/iTCO_version are evaluated,
and I don't find anything special regarding v4 in the Linux driver on
first glance. Most trickiest might be identifying the right register
layout (iTCO_version_regs) as this abstraction is specific to EBG.

Jan

--
Siemens AG, Technology
Competence Center Embedded Linux

[Arturs Laizans]

Hello Jan,

Thanks for the response.

Step 1 is pretty much straight forward. Any tips on getting the register layout? Should I reach out to Intel for a datasheet?

Best,
Arturs

[Jan Kiszka]

On 03.05.23 11:56, 'Arturs Laizans' via EFI Boot Guard wrote:
> Hello Jan,
>
> Thanks for the response.
>
> Step 1 is pretty much straight forward. Any tips on getting the register
> layout? Should I reach out to Intel for a datasheet?

I would simply read the kernel driver code.

Jan

>
> Best,
> Arturs
>
> On Mon, May 1, 2023 at 2:47 PM Jan Kiszka <jan.k...@siemens.com
> <mailto:jan.k...@siemens.com>> wrote:
>
> On 28.04.23 17:38, 'Arturs Laizans' via EFI Boot Guard wrote:
> > Hello List!
> >
> > I am looking forward to implementing support for ITCO version 4.
> We need
> > it for Intel Kaby Lake U processor (Celeron 3965U) equipd with Sunrise
> > Point-LP SMBus (PCI device ID 0x9D23).
> >
> > I have no prior experience with this. Are there any tips or heads up
> > advice I should consider?
>
> There are two major steps here:
> 1. detect the LPC PCI device of your board in itco.c (iTCO_chipset_info)
> 2. take the needed actions for ITCO_V4, deriving it from the kernel's
>    drivers/watchdog/iTCO_wdt.c
>
> There are not many places where itco_version/iTCO_version are evaluated,
> and I don't find anything special regarding v4 in the Linux driver on
> first glance. Most trickiest might be identifying the right register
> layout (iTCO_version_regs) as this abstraction is specific to EBG.
>
> Jan
>
> --
> Siemens AG, Technology
> Competence Center Embedded Linux
>

> --
> You received this message because you are subscribed to the Google
> Groups "EFI Boot Guard" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to efibootguard-d...@googlegroups.com
> <mailto:efibootguard-d...@googlegroups.com>.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/efibootguard-dev/CAHrV9oU-HDynZ0Wbbuvwhy3s1tq3%2Bfo1tydJQqmo%3D99tCaw5xA%40mail.gmail.com <https://groups.google.com/d/msgid/efibootguard-dev/CAHrV9oU-HDynZ0Wbbuvwhy3s1tq3%2Bfo1tydJQqmo%3D99tCaw5xA%40mail.gmail.com?utm_medium=email&utm_source=footer>.