Re: [PATCH v4] target/ppc: fix Hash64 MMU update of PTE bit R

[Cédric Le Goater]

On 11/30/21 21:00, Leandro Lupori wrote:
> On 30/11/2021 05:44, Cédric Le Goater wrote:
> > It would be interesting to boot directly the PowerNV machine from a
> > FreeBSB kernel and a minimum inirtd without using the skiroot images
> > and an iso. Are images available ?
>
> AFAIK there are no minimum initrd images available. The closest thing would be the 
> "bootonly" ISOs that can be found in the links below:
>
> https://download.freebsd.org/ftp/releases/powerpc/powerpc64/ISO-IMAGES/13.0/
>
> https://download.freebsd.org/ftp/releases/powerpc/powerpc64le/ISO-IMAGES/13.0/
>
> https://download.freebsd.org/ftp/snapshots/powerpc/powerpc64/ISO-IMAGES/14.0/
>
> https://download.freebsd.org/ftp/snapshots/powerpc/powerpc64le/ISO-IMAGES/14.0/
>
>
> But to avoid using skiroot, you would need to manually extract the kernel from the ISO 
> and also specify the rootfs, using something like: "-append cd9660:cd0".
> If you don't want to emulate a disk or cd, the ISO can be passed to -initrd and 
> "-append cd9660:md0" may be used to tell FreeBSD where to find the root 
> partition (it loads it as a memory disk).

The ISO is too big for quick tests. Isn't there a minimum initrd ? can we build 
a
builroot-like image for FreeBSD ?

> There are also qcow2 snapshots available:
>
> https://artifact.ci.freebsd.org/snapshot/14.0-CURRENT/latest/powerpc/powerpc64/
>
> https://artifact.ci.freebsd.org/snapshot/14.0-CURRENT/latest/powerpc/powerpc64le/
>
> But you'll also need to extract the kernel from the image or from kernel.txz to 
> boot them.

ok. I will take a look.

> As these images target pseries and lack a FAT32 partition, Petitboot won't be 
> able to boot them.

The idea would be to skip petitboot and load directly the FreeBSD kernel from 
skiboot
with a minimum initrd or disk image. See :

  
https://github.com/legoater/qemu-ppc-boot/blob/main/buildroot/qemu_ppc64le_powernv-2021.11-rc1-199-g927444a04e-20211120/start-qemu.sh

or

  
https://github.com/legoater/qemu-ppc-boot/blob/main/buildroot/qemu_ppc64le_pseries-2021.11-rc1-199-g927444a04e-20211120/start-qemu.sh

Thanks,

C.

> Alfredo (cc'ed) was trying to make them Petitboot compatible.