ARM with Qemu

Adam Lackorzynski adam at
Tue Mar 17 23:11:24 CET 2015

Hi Nicolas,

On Mon Mar 16, 2015 at 10:41:21 +0100, Nicolas VARONA wrote:
> >FPU support also needs to be enabled in Fiasco. I suppose it is?
> I had already enabled FPU in Fiasco like this:

Ok, good.

> I checked the CPACR register and the bits look ok. VFP is also enabled on the board. So you are right, it seems to be something else.

Other issue could be a missing CONFIG_AEABI.

> >Which ramdisk are you using?
> I use the ramdisk given in the files in the l4re-snapshot-2014092821: "ramdisk-arm.rd"


> >Do you have the 'log = L4.Env.log' statement in the script for launching L4Linux?
> >Do not start anything else which uses 'log = L4.Env.log'.
> I firstly tested adding this log without commenting the others. I don't have inputs on L4linux with Qemu. So I tried with only the 'log = L4.Env.log'. I have the same result with no input and I still can enter into the JDB.
> This is the "l4lx.cfg" file I used:
> -- vim:set ft=lua:
> local lxname = "vmlinuz";
> if L4.Info.arch() == "arm" then
>   lxname = "vmlinuz.arm";
> end

You need to have it like this:

   { caps = {
       log = L4.Env.log:m("rws"),
   "rom/" .. lxname .. " mem=64M console=ttyLv0 l4x_rd=rom/ramdisk-" ..  L4.Info.arch() .. ".rd root=1:0 ramdisk_size=4000");

But I suppose you tried that already?

> >What is Linux telling us about ttyLv0?
> During the boot with the configuration file I gave you, I can see:
> [...]
> ttyLv0 at MMIO 0x1 (irq = 211, base_baud = 230400) is a L4
> [...]

That looks fine.

Adam                 adam at

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