On Wed, Jan 8, 2014 at 2:48 PM, Arnd Bergmann [off-list ref] wrote:

On Wednesday 08 January 2014 15:43:20 Tomi Valkeinen wrote:

quoted

On 2013-12-18 01:37, Mark Brown wrote:

quoted

From: Mark Brown <redacted>

arm64 is unlikely to have a VGA console and does not export screen_info
causing build failures if the driver is build, for example in all*config.
Add a dependency on !ARM64 to prevent this.

This list is getting quite long, it may be easier to depend on a symbol
which architectures that do support the driver can select.

I agree, that depends on looks horrible =).

I've suggested creating a "CONFIG_PC_IO" symbol before that could used
to simplify this one and a couple of other similar Kconfig statements.
It is unfortunately a bit tricky because out of the dozen drivers that
are similar to this one, each one has a slightly different list of
architectures, and it's not clear which of the differences are intentional
rather than mistakes.

VGA is special, in that it uses "ISA memory space". This is not a subset of
"PCI memory space", but something different. Some PCI host bridges
(IIRC, e.g. on Mac) do not allow access to this space.
Most other "PC I/O" use ISA I/O space, which is a subset of PCI I/O space.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds