Re: [PATCH 2/2] arch: arm64: xilinx: Make zynqmp_firmware driver optional

[Jolly Shah]

Hi Michal,

> ------Original Message------
> From: Michal Simek <michal.simek@xxxxxxxxxx>
> Sent:  Monday, February 24, 2020 2:43AM
> To: Jolly Shah <jolly.shah@xxxxxxxxxx>, Ard.biesheuvel@xxxxxxxxxx 
<ard.biesheuvel@xxxxxxxxxx>, Mingo@xxxxxxxxxx <mingo@xxxxxxxxxx>, 'Greg 
Kh' <gregkh@xxxxxxxxxxxxxxxxxxx>, Matt@xxxxxxxxxxxxxxxxxxx 
<matt@xxxxxxxxxxxxxxxxxxx>, Sudeep.holla@xxxxxxx <sudeep.holla@xxxxxxx>, 
Hkallweit1@xxxxxxxxx <hkallweit1@xxxxxxxxx>, Keescook@xxxxxxxxxxxx 
<keescook@xxxxxxxxxxxx>, Dmitry.torokhov@xxxxxxxxx 
<dmitry.torokhov@xxxxxxxxx>, Michal Simek <michal.simek@xxxxxxxxxx>
> Cc: Rajan Vaja <rajanv@xxxxxxxxxx>, 
Linux-arm-kernel@xxxxxxxxxxxxxxxxxxx 
<linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>, Linux-kernel@xxxxxxxxxxxxxxx 
<linux-kernel@xxxxxxxxxxxxxxx>, Tejas Patel <tejas.patel@xxxxxxxxxx>
> Subject: Re: [PATCH 2/2] arch: arm64: xilinx: Make zynqmp_firmware 
driver optional
>
> On 09. 01. 20 20:06, Jolly Shah wrote:
> > From: Tejas Patel <tejas.patel@xxxxxxxxxx>
> >
> > Zynqmp firmware driver requires firmware to be present in system.
> > Zynqmp firmware driver will crash if firmware is not present in system.
> > For example single arch QEMU, may not have firmware, with such setup
> > Linux booting fails.
>
>
> I think that moving it to firmware Kconfig is good solution. What it is
> wrong is that description above where I agree with Sudeep.
> It means.
> 1. User should have option to disable zynqmp firmware driver which is
> what this patch allows. It means if someone decides to use different
> firmware mechanism it can do it directly by simply y/n option.
>
> 2. Autodetection of PMUFW presence is another feature which could be
> implemented to have this driver enabled but different mechanism can be
> used.
>
> 3. Doing this because of missing feature in QEMU is IMHO wrong. QEMU
> should be fixed and then you don't have any issue if this should be used
> or not.
>
> Just a summary. Remove that QEMU example from commit message and talk to
> Edgar to fix single QEMU solution to have that regs mapped all the time.

Pushed another patch as suggested. Will sync up with Edgar.

Thanks,
Jolly Shah

> Thanks,
> Michal