[igt-dev] [PATCH i-g-t] igt/kms_addfb_basic: require display

[Maarten Lankhorst]

Op 28-06-18 om 13:54 schreef Daniel Vetter:
> On Thu, Jun 28, 2018 at 12:19:57PM +0200, Maarten Lankhorst wrote:
>> Op 28-06-18 om 11:56 schreef Jani Nikula:
>>> Running the tests with i915.disable_display=1 leads to IGT errors. Skip
>>> tests that need display.
>>>
>>> References: http://patchwork.freedesktop.org/patch/msgid/20180608124057.6889-1-jani.nikula@intel.com
>>> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>>> Cc: Daniel Vetter <daniel at ffwll.ch>
>>> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
>>> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
>>>
>>> ---
>>>
>>> What's the best paradigm for this? There's loads of random and cargo
>>> culted igt_requires for this stuff, with various checks on pipes > 0
>>> etc.
>>> ---
>> igt_display_require_output() is the easiest check to find if an output
>> is connected, should be approximately same as display enabled. :)
> Unfortunately not quite. I think we do want to run these tests here on
> headless systems which have a display block, but no outputs connected.
> Just for better test coverage and all that.
>
> I think what we want is a new
>
> igt_require_display(int fd)
> {
> 	igt_display_t display;
> 	igt_display_init(&display, fd);
> 	igt_require(display->n_pipes > 0, "drm driver without display
> 	hardware\n");
> }
>
> gtkdoc plus wiring it up needed too ofc.
>
> We could also patch up igt_display_init() to check for this (and probably
> should, not sure about that), but a very simply igt_require helper that
> only takes the fd seems useful to me for all the low-level tests like
> kms_addfb_basic here which don't want/need a full igt_display_t
> initialized.
But igt_display is not without side effects. It sets the atomic cap, which would be surprising in a require statement.

i915 without pipes should probably unset DRIVER_MODESET.