Re: [PATCH v4 07/41] drm: handle HAS_IOPORT dependencies

From: Arnd Bergmann
Date: Tue May 16 2023 - 13:48:04 EST


On Tue, May 16, 2023, at 19:13, Thomas Zimmermann wrote:
>
> Am 16.05.23 um 13:00 schrieb Niklas Schnelle:
>> In a future patch HAS_IOPORT=n will result in inb()/outb() and friends
>> not being declared. We thus need to add HAS_IOPORT as dependency for
>> those drivers using them. In the bochs driver there is optional MMIO
>> support detected at runtime, warn if this isn't taken when
>> HAS_IOPORT is not defined.
>>
>> There is also a direct and hard coded use in cirrus.c which according to
>> the comment is only necessary during resume. Let's just skip this as
>> for example s390 which doesn't have I/O port support also doesen't
>> support suspend/resume.
>>
>> Co-developed-by: Arnd Bergmann <arnd@xxxxxxxxxx>
>> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxxxx>
>> Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
>> ---
>> Note: The HAS_IOPORT Kconfig option was added in v6.4-rc1 so
>> per-subsystem patches may be applied independently
>>
>> drivers/gpu/drm/qxl/Kconfig | 1 +
>> drivers/gpu/drm/tiny/bochs.c | 17 +++++++++++++++++
>> drivers/gpu/drm/tiny/cirrus.c | 2 ++
>
> There are more invocations in gma500. See[1]
>
> [1]
> https://elixir.bootlin.com/linux/v6.3/source/drivers/gpu/drm/gma500/cdv_device.c#L30

GMA500 already has "depends on X86", so I don't think
any changes are needed there -- x86 is already highly dependent
on I/O ports for a number of reasons.

Arnd