+++ Antonio Terceiro [2013-09-04 20:41 -0300]:
On Tue, Sep 03, 2013 at 05:44:13PM +0100, Wookey wrote:
Xen requires a non-standard boot with the hypervisor loaded as well as the kernel before booting (and rootfs unpacked).
Julien says we need to do (at least some of) the config on this page before running XEN: http://wiki.xen.org/wiki/Xen_ARM_with_Virtualization_Extensions/Vexpress which involves disabling the A7 (required), and one way of loading the stuff in the right places, which there may be uboot/uefi-based alternatives to?). This config is done in images.txt and board.txt files.
Those files apparently live on the second, internal, microSD card.
The card can apparently be exposed as a fat filesystem over USB (usb-storage). Is that cable plugged in?
It is.
Is there a lava mechanism for accessing this and updating it?
Yes, but at the moment it's only used to replace the UEFI binary with the one that comes with the test disk image. It would be possible to add some code that will also replace other files in there.
Is this code that we have to add to lava and then release into production, or can we issue interactive_boot_cmds sendline/expect foo to get this done for now?
(Which machine is actually issuing those commands in lava? I haven't got the architecture properly understood in my head, which makes this confusing to think about. Although I guess the idea is that lava wraps all that so I shouldn't need to know. I think I do need to know the device name of this SD-card if we are doing mount;change file;unmount in interactive_boot_cmds. And presumably $something needs to remember to put the default one back again after this job runs, which is the real reason why lava needs to support it properly?
What firmware version (boot monitor) is in the machine in the lab?
ARM Versatile Express Boot Monitor Version: V5.1.9
OK so according to http://wiki.xen.org/wiki/Xen_ARM_with_Virtualization_Extensions/Vexpress this is not new enough to use SCC: 0x700 0x0032E003 and we have to use SCC: 0x018 0x00001FFF instead, if I have understood that page right.
What is currently in the images.txt, board.txt files it is booting with? Is 'sys_flags' bringup already selected or not?
It is not.
OK. The Xen page says "Xen only supports sys_flags bring up". So what does this mean? Can we turn it on, can we change Xen? (I don't know why I have this job - I have absolutely no idea what I am talking about :-) All I get to do is badger about 5 other people who _do_ have some clue :-)
Cheers for your help so far, the murk may be clearing slowly...
Wookey