Re: xen cache colors in ARM

[Michal Orzel <michal.orzel@xxxxxxx>]

Hi Oleg,

On 19/04/2023 09:03, Oleg Nikitenko wrote:
>       
> 
> 
> Hello Stefano,
> 
> Thanks for the clarification.
> My company uses yocto for image generation.
> What kind of information do you need to consult me in this case ?
> 
> Maybe modules sizes/addresses which were mentioned by @Julien Grall 
> <mailto:julien@xxxxxxx> ?

Sorry for jumping into discussion, but FWICS the Xen command line you provided 
seems to be not the one
Xen booted with. The error you are observing most likely is due to dom0 colors 
configuration not being
specified (i.e. lack of dom0_colors=<> parameter). Although in the command line 
you provided, this parameter
is set, I strongly doubt that this is the actual command line in use.

You wrote:
xen,xen-bootargs = "console=dtuart dtuart=serial0 dom0_mem=1600M 
dom0_max_vcpus=2 dom0_vcpus_pin bootscrub=0 vwfi=native sched=null timer_slop=0 
way_szize=65536 xen_colors=0-3 dom0_colors=4-7";

but:
1) way_szize has a typo
2) you specified 4 colors (0-3) for Xen, but the boot log says that Xen has 
only one:
(XEN) Xen color(s): [ 0 ]

This makes me believe that no colors configuration actually end up in command 
line that Xen booted with.
Single color for Xen is a "default if not specified" and way size was probably 
calculated by asking HW.

So I would suggest to first cross-check the command line in use.

~Michal


> 
> Regards,
> Oleg
> 
> вт, 18 апр. 2023 г. в 20:44, Stefano Stabellini <sstabellini@xxxxxxxxxx 
> <mailto:sstabellini@xxxxxxxxxx>>:
> 
>     On Tue, 18 Apr 2023, Oleg Nikitenko wrote:
>     > Hi Julien,
>     >
>     > >> This feature has not been merged in Xen upstream yet
>     >
>     > > would assume that upstream + the series on the ML [1] work
>     >
>     > Please clarify this point.
>     > Because the two thoughts are controversial.
> 
>     Hi Oleg,
> 
>     As Julien wrote, there is nothing controversial. As you are aware,
>     Xilinx maintains a separate Xen tree specific for Xilinx here:
>     https://github.com/xilinx/xen <https://github.com/xilinx/xen>
> 
>     and the branch you are using (xlnx_rebase_4.16) comes from there.
> 
> 
>     Instead, the upstream Xen tree lives here:
>     https://xenbits.xen.org/gitweb/?p=xen.git;a=summary 
> <https://xenbits.xen.org/gitweb/?p=xen.git;a=summary>
> 
> 
>     The Cache Coloring feature that you are trying to configure is present
>     in xlnx_rebase_4.16, but not yet present upstream (there is an
>     outstanding patch series to add cache coloring to Xen upstream but it
>     hasn't been merged yet.)
> 
> 
>     Anyway, if you are using xlnx_rebase_4.16 it doesn't matter too much for
>     you as you already have Cache Coloring as a feature there.
> 
> 
>     I take you are using ImageBuilder to generate the boot configuration? If
>     so, please post the ImageBuilder config file that you are using.
> 
>     But from the boot message, it looks like the colors configuration for
>     Dom0 is incorrect.
>