Re: [PATCH] fpga: allow to compile-test Altera FPGA bridge drivers

[Tobias Klauser <tklauser@distanz.ch>]

Hi Alan,

On 2017-04-11 at 16:27:03 +0200, Alan Tull <atull@kernel.org> wrote:
> On Tue, Apr 11, 2017 at 4:22 AM, Tobias Klauser <tklauser@distanz.ch> wrote:
> 
> Hi Tobias,
> 
> Thanks for your fixes that you have been sending.  I disagree with
> this particular one (see below), but I appreciate your efforts.

Thanks for your feedback on the patch.

> > Add COMPILE_TEST to the Kconfig entries for the Altera SoCFPGA FPGA
> > Bridge and the Altera FPGA Freeze Bridge drivers to allow test-compiling
> > them on other architectures.
> >
> > Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
> > ---
> >  drivers/fpga/Kconfig | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> > index 161ba9dccede..38ab05d261bf 100644
> > --- a/drivers/fpga/Kconfig
> > +++ b/drivers/fpga/Kconfig
> > @@ -69,14 +69,14 @@ config FPGA_BRIDGE
> >
> >  config SOCFPGA_FPGA_BRIDGE
> >         tristate "Altera SoCFPGA FPGA Bridges"
> > -       depends on ARCH_SOCFPGA && FPGA_BRIDGE
> > +       depends on (ARCH_SOCFPGA || COMPILE_TEST) && FPGA_BRIDGE
> 
> It doesn't make sense to compile test these on other arch's.
> The bridges enabled by this only appear on Cyclone 5 SoCFPGA parts.

There are many drivers in the tree where this is the case (i.e. the
driver is compiled on an arch where the corresponding hardware is not
available). Still it could be benefitial IMO in order to catch compiler
errors and warnings, e.g. due to API/header changes earlier on. I
occasionally found this quite handy for janitorial/cleanup patches where
I didn't have the corresponding cross-compiler/hardware.

In any case, I don't feel strongly about this. So feel free to drop at
your discretion.

> >         help
> >           Say Y to enable drivers for FPGA bridges for Altera SOCFPGA
> >           devices.
> >
> >  config ALTERA_FREEZE_BRIDGE
> >         tristate "Altera FPGA Freeze Bridge"
> > -       depends on ARCH_SOCFPGA && FPGA_BRIDGE
> > +       depends on (ARCH_SOCFPGA || COMPILE_TEST) && FPGA_BRIDGE
> 
> These bridges can be used on Altera PCIe FPGA's.  So this shouldn't
> have been dependent on ARCH_SOCFPGA in the first place.

Ok. So the dependency on ARCH_SOCFPGA should be dropped altogether? I
can send an updated patch if you want.

> Alan
> 
> >         help
> >           Say Y to enable drivers for Altera FPGA Freeze bridges.  A
> >           freeze bridge is a bridge that exists in the FPGA fabric to
> > --
> > 2.12.2
> >
> >
>