[PATCH] Add support for RENDER BGRA formats.

Adam Jackson ajax at nwnk.net
Mon Nov 2 08:06:16 PST 2009

On Sat, 2009-10-31 at 16:17 +0100, Mark Kettenis wrote:

> > It might.  BAR 5 is the I/O map, and it's 256 bytes.  They're all
> > defined right up to 0xBC, which smells a little suspicious since the VGA
> > ports it claims to decode are 3C[0-5ACEF] and 3[BD][45A].  So while it
> > doesn't _say_ the VGA ports are aliased there starting at 0xC0, I'd be
> > utterly unsurprised.
> > 
> > I guess I don't see how it matters though, you can already get to the
> > colormap and mode, and you won't be using VGA fonts.  (Unless you do VGA
> > console even on non-x86 machines?  That would be vile.)
> You're right of course.  I already disabled the VGA font save/restore
> because that required mapping the legacy VGA memory area and on the
> Sun Blade 1000 that I stuck this card in, that area is in use by other
> devices.
> Still struggling a bit with how to map BAR 5 though.  I have a hack to
> make things work, but I'll need to discuss the implications for the
> OpenBSD kernel and libpciaccess.

Most non-x86 arches have a way to mmap the I/O space, but x86 (and
amd64) almost never does.  The portable way to do this would be like:

void *pci_device_open_io(struct pci_device *dev, int bar);
void pci_device_close_io(struct pci_device *dev, void *handle);
uint32_t pci_io_inl(void *handle, uint16_t reg);
uint16_t pci_io_inw(void *handle, uint16_t reg);
uint8_t pci_io_inb(void *handle, uint16_t reg);
void pci_io_outl(void *handle, uint16_t reg, uint32_t data);
void pci_io_outw(void *handle, uint16_t reg, uint16_t data);
void pci_io_outb(void *handle, uint16_t reg, uint8_t data);

On mappable arches the handle can be the mmap itself and the accessors
can be trivial, but on x86 it'd probably be the file handle
for /dev/port or the sysfs resource file and the accessors would be

- ajax
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