Re: [PATCH v4 2/4] hw/loongarch/virt-acpi-build: Drop UART _DSD clock and add _STA

[Igor Mammedov <imammedo@redhat.com>]

On Thu, 22 Oct 2026 17:25:00 +0800
way sorry <waysorrypub@gmail.com> wrote:

> Hi Igor,
> 
> One additional observation: QEMU's x86 ISA serial implementation explicitly
> defines _STA =
> 0x0f in serial_isa_build_aml(), rather than relying on the ACPI default:
> 
> https://github.com/qemu/qemu/blob/8967b2fe1b2aaae3c29e207d85fab901d580a2dc/hw/char/serial-isa.c#L101
> 
> I think following the same approach for LoongArch UART would be reasonable
> for consistency.

preexisting code in this case is not a good example to follow.

if it works without adding unnecessary stuff, do not add it.


DSD and CCA changes are also unrelated => separate patches

> 
> Thanks,
> pillow
> 
> On Thu, Oct 22, 2026 at 5:01 PM way sorry <waysorrypub@gmail.com> wrote:
> 
> > Hi Igor,
> >
> > The _STA method was added in response to Bibo's review comment on the
> > original patch, where
> > he explicitly suggested adding _STA.
> >
> > I understand your concern that omitting _STA already implies 0x0f.
> > However, the two review
> > comments seem to suggest different approaches.
> >
> > I'm happy to split the changes into separate patches as required. For
> > _STA, though, I'd
> > appreciate it if we could first agree on whether it should be added or
> > omitted, so I have a clear
> > direction for the next version.
> >
> > Thanks,
> > pillow
> >
> > On Thu, Oct 22, 2026 at 4:18 PM Igor Mammedov <imammedo@redhat.com> wrote:
> >  
> >> On Thu, 22 Oct 2026 15:22:36 +0800
> >> pillow <waysorrypub@gmail.com> wrote:
> >>
> >> ...  
> >> > @@ -325,7 +324,7 @@ static void build_uart_device_aml(Aml *table, int  
> >> index)
> >> ...  
> >> > +    aml_append(dev, aml_name_decl("_STA", aml_int(0x0f)));  
> >>
> >> also is it really necessary? Doesn't missing _STA imply 0xF already?
> >>  
> >> >      crs = aml_resource_template();
> >> >      aml_append(crs,
> >> >          aml_qword_memory(AML_POS_DECODE, AML_MIN_FIXED, AML_MAX_FIXED,  
> >>
> >>