Re: xen cache colors in ARM

[Michal Orzel <michal.orzel@xxxxxxx>]

On 21/04/2023 10:04, Oleg Nikitenko wrote:
>       
> 
> 
> Hello Michal,
> 
> Yes, I use yocto.
> 
> Yesterday all day long I tried to follow your suggestions.
> I faced a problem.
> Manually in the xen config build file I pasted the strings:
In the .config file or in some Yocto file (listing additional Kconfig options) 
added to SRC_URI?
You shouldn't really modify .config file but if you do, you should execute 
"make olddefconfig" afterwards.

> 
> CONFIG_EARLY_PRINTK
> CONFIG_EARLY_PRINTK_ZYNQMP
> CONFIG_EARLY_UART_CHOICE_CADENCE
I hope you added =y to them.

Anyway, you have at least the following solutions:
1) Run bitbake xen -c menuconfig to properly set early printk
2) Find out how you enable other Kconfig options in your project (e.g. 
CONFIG_COLORING=y that is not enabled by default)
3) Append the following to "xen/arch/arm/configs/arm64_defconfig":
CONFIG_EARLY_PRINTK_ZYNQMP=y

~Michal

> 
> Host hangs in build time. 
> Maybe I did not set something in the config build file ?
> 
> Regards,
> Oleg
> 
> чт, 20 апр. 2023 г. в 11:57, Oleg Nikitenko <oleshiiwood@xxxxxxxxx 
> <mailto:oleshiiwood@xxxxxxxxx>>:
> 
>     Thanks Michal,
> 
>     You gave me an idea.
>     I am going to try it today.
> 
>     Regards,
>     O.
> 
>     чт, 20 апр. 2023 г. в 11:56, Oleg Nikitenko <oleshiiwood@xxxxxxxxx 
> <mailto:oleshiiwood@xxxxxxxxx>>:
> 
>         Thanks Stefano.
> 
>         I am going to do it today.
> 
>         Regards,
>         O.
> 
>         ср, 19 апр. 2023 г. в 23:05, Stefano Stabellini 
> <sstabellini@xxxxxxxxxx <mailto:sstabellini@xxxxxxxxxx>>:
> 
>             On Wed, 19 Apr 2023, Oleg Nikitenko wrote:
>             > Hi Michal,
>             >
>             > I corrected xen's command line.
>             > Now it is
>             > 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_size=65536 xen_colors=0-3 dom0_colors=4-7";
> 
>             4 colors is way too many for xen, just do xen_colors=0-0. There 
> is no
>             advantage in using more than 1 color for Xen.
> 
>             4 colors is too few for dom0, if you are giving 1600M of memory 
> to Dom0.
>             Each color is 256M. For 1600M you should give at least 7 colors. 
> Try:
> 
>             xen_colors=0-0 dom0_colors=1-8
> 
> 
> 
>             > Unfortunately the result was the same.
>             >
>             > (XEN)  - Dom0 mode: Relaxed
>             > (XEN) P2M: 40-bit IPA with 40-bit PA and 8-bit VMID
>             > (XEN) P2M: 3 levels with order-1 root, VTCR 0x0000000080023558
>             > (XEN) Scheduling granularity: cpu, 1 CPU per sched-resource
>             > (XEN) Coloring general information
>             > (XEN) Way size: 64kB
>             > (XEN) Max. number of colors available: 16
>             > (XEN) Xen color(s): [ 0 ]
>             > (XEN) alternatives: Patching with alt table 00000000002cc690 -> 
> 00000000002ccc0c
>             > (XEN) Color array allocation failed for dom0
>             > (XEN)
>             > (XEN) ****************************************
>             > (XEN) Panic on CPU 0:
>             > (XEN) Error creating domain 0
>             > (XEN) ****************************************
>             > (XEN)
>             > (XEN) Reboot in five seconds...
>             >
>             > I am going to find out how command line arguments passed and 
> parsed.
>             >
>             > Regards,
>             > Oleg
>             >
>             > ср, 19 апр. 2023 г. в 11:25, Oleg Nikitenko 
> <oleshiiwood@xxxxxxxxx <mailto:oleshiiwood@xxxxxxxxx>>:
>             >       Hi Michal,
>             >
>             > You put my nose into the problem. Thank you.
>             > I am going to use your point.
>             > Let's see what happens.
>             >
>             > Regards,
>             > Oleg
>             >
>             >
>             > ср, 19 апр. 2023 г. в 10:37, Michal Orzel <michal.orzel@xxxxxxx 
> <mailto: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 <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> 
> <mailto: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> <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> 
> <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.
>             >       >
>             >
>             >
>             > 
>