Re: [PULL v4 46/83] acpi: pc/q35: drop ad-hoc PCI-ISA bridge AML routines and let bus ennumeration generate AML

[Igor Mammedov]

On Thu, 17 Nov 2022 22:51:46 +0100
Volker Rümelin <vr_qemu@t-online.de> wrote:

> > From: Igor Mammedov<imammedo@redhat.com>
> >
> > PCI-ISA bridges that are built in PIIX/Q35 are building its own AML
> > using AcpiDevAmlIf interface. Now build_append_pci_bus_devices()
> > gained AcpiDevAmlIf interface support to get AML of devices atached
> > to PCI slots.
> > So drop ad-hoc build_q35_isa_bridge()/build_piix4_isa_bridge()
> > and let PCI bus enumeration to include PCI-ISA bridge AML
> > when it's enumerated by build_append_pci_bus_devices().
> >
> > AML change is mostly contextual, which moves whole ISA hierarchy
> > directly under PCI host bridge instead of it being described
> > as separate \SB.PCI0.ISA block.
> >
> > Note:
> > If bus/slot that hosts ISA bridge has BSEL set, it will gain new
> > ASUN and _DMS entries (i.e. acpi-index support, but it should not
> > cause any functional change and that is fine from PCI Firmware
> > spec point of view), potentially it's possible to suppress that
> > by adding a flag to PCIDevice but I don't see a reason to do that
> > yet, I'd rather treat bridge just as any other PCI device if it's
> > possible.
> >
> > Signed-off-by: Igor Mammedov<imammedo@redhat.com>
> > Message-Id:<20221017102146.2254096-4-imammedo@redhat.com>
> > Reviewed-by: Michael S. Tsirkin<mst@redhat.com>
> > Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
> > ---
> >   hw/i386/acpi-build.c | 75 --------------------------------------------
> >   hw/isa/lpc_ich9.c    | 23 ++++++++++++++
> >   hw/isa/piix3.c       | 17 +++++++++-
> >   3 files changed, 39 insertions(+), 76 deletions(-)  
> 
> Hi Igor,
> 
> since this patch SeaBIOS no longer detects the PS/2 keyboard. This means 
> there's no keyboard in SeaBIOS, GRUB or FreeDOS. OVMF and Linux detect 
> the PS/2 keyboard without issues.
> 
> Here are a few lines from the SeaBIOS debug log.
> 
> table(50434146)=0x007e1971 (via rsdt)
> ACPI: parse DSDT at 0x007e0040 (len 6449)
> parse_termlist: parse error, skip from 92/465
> Scan for VGA option rom
> Running option rom at c000:0003
> Start SeaVGABIOS (version rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org)
> 
> and later
> 
> SeaBIOS (version rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org)
> ACPI: no PS/2 keyboard present

it looks like SeaBIOS looks for EISA id,
but what is strange is that this patch doesn't have anything
that touches eisaid.

I'll have to debug seabios to figure out why this patch
affects it.

> 
> It doesn't matter if the machine type is pc or q35.
> 
> If I revert this patch, the PS/2 keyboard works again.
> 
> With best regards,
> Volker
> 
> 
> 
> 
>