On Mon Apr 28, 2025 at 05:25:34 +0000, Moshe Kravchik wrote:
> Thanks a lot, Adam!
> I added both and rebuilt the device tree, but now I'm getting:
> ```
> vm-1    | VMM[smccc_proxy]: smccc_proxy
> vm-1    | VMM: smccc_proxy.l4vmm,smccc_cap: capability smc is invalid.
> vm-1    | VMM[vm]: Device creation for virtual device smccc_proxy failed. Disabling device.
> ```

This tells that the 'smc' cap is not there in uvmm. Is it there in the
'caps' table with which uvmm is started? There, where "ram = ..." is
as well: caps = { ram = ...., smc = L4.Env.arm_smc, }, ....
Additionally, in the microkernel, the CONFIG_ARM_SMC_USER option must
also be enabled.


Adam

> Moshe
> ________________________________
> From: Adam Lackorzynski <adam@l4re.org>
> Sent: Monday, April 28, 2025 12:07 AM
> To: Moshe Kravchik <mkravchik@hotmail.com>; l4-hackers@os.inf.tu-dresden.de <l4-hackers@os.inf.tu-dresden.de>
> Subject: Re: Linux fails on startup looking for SMC
>
> Hi Moshe,
>
> On Sun Apr 27, 2025 at 15:32:53 +0000, Moshe Kravchik wrote:
> > Hi,
> > I'm trying to set up a Linux running on uvmm with a HW passthrough.
> > I added `zynqmp_firmware` to my DTS (it was required for the device I'm trying to pass).
> > However, Linux fails to add the device and I see:
> > vm-1 | [ 1.772078] ledtrig-cpu: registered to indicate activity on CPUs
> > vm-1 | VMM[guest]: No handler for SMC call: imm=0 a0=c200003f a1=3f ip=ffff800080026884 lr=ffff800080dcdb04
> > vm-1 | VMM[guest]: No handler for SMC call: imm=0 a0=c2000001 a1=0 ip=ffff800080026884 lr=ffff800080dcdb04
> > vm-1 | [ 1.805957] zynqmp_firmware firmware:zynqmp-firmware: probe with driver zynqmp_firmware failed with error -22
> >
> > >From the traces I added, the failure is in `zynqmp_pm_get_api_version`.
> >
> > How do I add SMC handling?
>
> You give uvmm in the Ned script: smc = L4.Env.arm_smc
>
> And put this into you device tree:
>    smccc_proxy {
>        compatible = "l4vmm,smccc_proxy";
>        l4vmm,smccc_cap = "smc";
>        method = "smc";
>    };
>
> Note that L4.Env.arm_smc gives access to the real interface with all the
> power that is behind it (the kernel only filters its range). So in a
> longer run it might be necessary to have proxy for this interface, or
> emulate the SMCs, or modify Linux to not use it, whatever fits best.
>
>
>
> Adam