Re: [PATCH 1/3] ati-vga: Fix aperture sizes

[BALATON Zoltan]

On Mon, 30 Oct 2023, Marc-André Lureau wrote:
> Hi
>
> On Tue, Oct 10, 2023 at 5:03 PM BALATON Zoltan <balaton@eik.bme.hu> wrote:
> > Apparently these should be half the memory region sizes confirmed at
> > least by Radeon drivers while Rage 128 Pro drivers don't seem to use
> > these.
>
> There doesn't seem to be adjustments for the kernel PPC driver
> https://github.com/torvalds/linux/blob/master/drivers/video/fbdev/aty/radeon_base.c#L2037
>
> Do you have any other pointers?

There was some discussion back whan this was added:

https://patchew.org/QEMU/99bb800cba3596e47d2681642116756330dc6f63.1562320946.git.balaton@eik.bme.hu/

and this was also in a patch Gerd sent once around that time but I don't 
find that patch now. I've found this while trying to get some RV100 ROMs 
from real card running which did multiply this by 2 while the Rage128Pro 
ROMs and drivers did not access it and used the BAR sizes I think. 
According to the discussion above maybe this also depends on some other 
bit but I don't have detailed enough docs to know.

Regards,
BALATON Zoltan

> thanks
>
> > Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
> > ---
> >  hw/display/ati.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/display/ati.c b/hw/display/ati.c
> > index c36282c343..f0bf1d7493 100644
> > --- a/hw/display/ati.c
> > +++ b/hw/display/ati.c
> > @@ -349,14 +349,14 @@ static uint64_t ati_mm_read(void *opaque, hwaddr addr, 
> > unsigned int size)
> >                                        PCI_BASE_ADDRESS_0, size) & 0xfffffff0;
> >          break;
> >      case CONFIG_APER_SIZE:
> > -        val = s->vga.vram_size;
> > +        val = s->vga.vram_size / 2;
> >          break;
> >      case CONFIG_REG_1_BASE:
> >          val = pci_default_read_config(&s->dev,
> >                                        PCI_BASE_ADDRESS_2, size) & 0xfffffff0;
> >          break;
> >      case CONFIG_REG_APER_SIZE:
> > -        val = memory_region_size(&s->mm);
> > +        val = memory_region_size(&s->mm) / 2;
> >          break;
> >      case MC_STATUS:
> >          val = 5;
> > --
> > 2.30.9