Re: [PATCH v3 3/4] hw/acpi: add indication for i8042 in IA-PC boot flags of the FADT table

[Ani Sinha]

On Mon, Feb 28, 2022 at 12:26 PM Ani Sinha <ani@anisinha.ca> wrote:
>
>
>
> > > >ObjectClass type->name here :)
> > >
> > > I see. What about object_resolve_path_type()? It takes a typename 
> > > parameter. It even tells you if the match is ambiguous if you care.
> >
> > Yes this is a good suggestion and it will likely work.
> > You can get rid of your first patch and only make the following change:
> >
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index 65dbc1ec36..d82c39490c 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -38,6 +38,7 @@
> >  #include "hw/nvram/fw_cfg.h"
> >  #include "hw/acpi/bios-linker-loader.h"
> >  #include "hw/isa/isa.h"
> > +#include "hw/input/i8042.h"
> >  #include "hw/block/fdc.h"
> >  #include "hw/acpi/memory_hotplug.h"
> >  #include "sysemu/tpm.h"
> > @@ -198,7 +199,7 @@ static void init_common_fadt_data(MachineState
> > *ms, Object *o,
> >       * (the earliest acpi revision that supports this).
> >       */
> >
> > -    fadt.iapc_boot_arch = isa_check_device_existence("i8042") ?
> > 0x0002 : 0x0000;
> > +    fadt.iapc_boot_arch = object_resolve_path_type("", TYPE_I8042,
> > NULL) ? 0x0002 : 0x0000;
>
>
> This might be incorrect if there are more than one device of that type.
> You need to check for ambiguity as well.

exactly one is added by default, the ISA bus with or without -nodefaults:

~/workspace/qemu/build$ echo -e "info qtree\r\nquit\r\n" |
./qemu-system-x86_64 -monitor stdio 2>/dev/null | grep 8042
          dev: i8042, id ""
~/workspace/qemu/build$ echo -e "info qtree\r\nquit\r\n" |
./qemu-system-x86_64 -nodefaults -monitor stdio 2>/dev/null | grep
8042
          dev: i8042, id ""