Re: [Question] Regarding PMU initialization within the QEMU for ARM VCPUs

[Igor Mammedov]

On Fri, 5 Jun 2020 16:38:37 +0000
Salil Mehta <salil.mehta@huawei.com> wrote:

> > From: Igor Mammedov [mailto:imammedo@redhat.com]
> > Sent: Friday, June 5, 2020 4:31 PM
> > To: Andrew Jones <drjones@redhat.com>
> > Cc: Salil Mehta <salil.mehta@huawei.com>; qemu-devel@nongnu.org;
> > qemu-arm@nongnu.org; Peter Maydell <peter.maydell@linaro.org>; 
> > mst@redhat.com
> > Subject: Re: [Question] Regarding PMU initialization within the QEMU for ARM
> > VCPUs
> > 
> > On Wed, 3 Jun 2020 11:37:45 +0200
> > Andrew Jones <drjones@redhat.com> wrote:
> >   
> > > On Mon, Jun 01, 2020 at 03:04:33PM +0000, Salil Mehta wrote:  
> > > > Hello,
> > > > I could see below within function fdt_add_pmu_nodes() part of
> > > > hw/arm/virt.c during virt machine initialization time:  
> > ...  
> > >  
> > > > Q4. This function  fdt_* looks to be wrongly named. The info
> > > >     being initialized here shall be used even when ACPI is
> > > >     being used. Initialization part and FDT info looked
> > > >     mixed up here if I am right?  
> > >
> > > Agreed. The function has the wrong name. mach-virt has many functions that
> > > mix the initialization and fdt building together, but those functions are
> > > named something like create_foo(). Patches welcome.  
> > that was where I gave up on cpu hotplug arm/virt the last time.  
> 
> Were you releasing the ARM objects as well? Or are you referring to some
> other problem?
I was talking about mix of FDT and device creation code.

> 
> > Ideally we should split out from create_foo() all firmware generation code
> > (fdt) and move it to virt_machine_done time + make sure that it could be
> > regenerated at reset time so guest would get updated FDT on reset.  
> 
> Agreed, just like ACPI part. That would be more cleaner. 
> 
> Thanks
> Salil.
> 
>