On Tue, Sep 29, 2020 at 8:31 AM Jan Kiszka <jan.kis...@web.de> wrote:
>
> On 10.09.20 20:18, Deucher, Alexander wrote:
> > [AMD Public Use]
> >
> >
> >
> >> -----Original Message-----
> >> From: amd-gfx <amd-gfx-boun...@lists.freedesktop.org> On Behalf Of
> >> Daniel Vetter
> >> Sent: Monday, September 7, 2020 3:15 AM
> >> To: Jan Kiszka <jan.kis...@web.de>; amd-gfx list <amd-
> >> g...@lists.freedesktop.org>; Wentland, Harry <harry.wentl...@amd.com>;
> >> Kazlauskas, Nicholas <nicholas.kazlaus...@amd.com>
> >> Cc: dri-devel <dri-devel@lists.freedesktop.org>; intel-gfx <intel-
> >> g...@lists.freedesktop.org>; Thomas Zimmermann
> >> <tzimmerm...@suse.de>; Ville Syrjala <ville.syrj...@linux.intel.com>
> >> Subject: Re: [PATCH v3 6/7] drm: Validate encoder->possible_crtcs
> >>
> >> On Sun, Sep 6, 2020 at 1:19 PM Jan Kiszka <jan.kis...@web.de> wrote:
> >>>
> >>> On 11.02.20 18:04, Daniel Vetter wrote:
> >>>> On Tue, Feb 11, 2020 at 06:22:07PM +0200, Ville Syrjala wrote:
> >>>>> From: Ville Syrjälä <ville.syrj...@linux.intel.com>
> >>>>>
> >>>>> WARN if the encoder possible_crtcs is effectively empty or contains
> >>>>> bits for non-existing crtcs.
> >>>>>
> >>>>> v2: Move to drm_mode_config_validate() (Daniel)
> >>>>> Make the docs say we WARN when this is wrong (Daniel)
> >>>>> Extract full_crtc_mask()
> >>>>>
> >>>>> Cc: Thomas Zimmermann <tzimmerm...@suse.de>
> >>>>> Cc: Daniel Vetter <dan...@ffwll.ch>
> >>>>> Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
> >>>>
> >>>> When pushing the fixup needs to be applied before the validation
> >>>> patch here, because we don't want to anger the bisect gods.
> >>>>
> >>>> Reviewed-by: Daniel Vetter <daniel.vet...@ffwll.ch>
> >>>>
> >>>> I think with the fixup we should be good enough with the existing
> >>>> nonsense in drivers. Fingers crossed.
> >>>> -Daniel
> >>>>
> >>>>
> >>>>> ---
> >>>>> drivers/gpu/drm/drm_mode_config.c | 27
> >> ++++++++++++++++++++++++++-
> >>>>> include/drm/drm_encoder.h | 2 +-
> >>>>> 2 files changed, 27 insertions(+), 2 deletions(-)
> >>>>>
> >>>>> diff --git a/drivers/gpu/drm/drm_mode_config.c
> >>>>> b/drivers/gpu/drm/drm_mode_config.c
> >>>>> index afc91447293a..4c1b350ddb95 100644
> >>>>> --- a/drivers/gpu/drm/drm_mode_config.c
> >>>>> +++ b/drivers/gpu/drm/drm_mode_config.c
> >>>>> @@ -581,6 +581,29 @@ static void
> >> validate_encoder_possible_clones(struct drm_encoder *encoder)
> >>>>> encoder->possible_clones, encoder_mask); }
> >>>>>
> >>>>> +static u32 full_crtc_mask(struct drm_device *dev) {
> >>>>> + struct drm_crtc *crtc;
> >>>>> + u32 crtc_mask = 0;
> >>>>> +
> >>>>> + drm_for_each_crtc(crtc, dev)
> >>>>> + crtc_mask |= drm_crtc_mask(crtc);
> >>>>> +
> >>>>> + return crtc_mask;
> >>>>> +}
> >>>>> +
> >>>>> +static void validate_encoder_possible_crtcs(struct drm_encoder
> >>>>> +*encoder) {
> >>>>> + u32 crtc_mask = full_crtc_mask(encoder->dev);
> >>>>> +
> >>>>> + WARN((encoder->possible_crtcs & crtc_mask) == 0 ||
> >>>>> + (encoder->possible_crtcs & ~crtc_mask) != 0,
> >>>>> + "Bogus possible_crtcs: "
> >>>>> + "[ENCODER:%d:%s] possible_crtcs=0x%x (full crtc mask=0x%x)\n",
> >>>>> + encoder->base.id, encoder->name,
> >>>>> + encoder->possible_crtcs, crtc_mask); }
> >>>>> +
> >>>>> void drm_mode_config_validate(struct drm_device *dev) {
> >>>>> struct drm_encoder *encoder;
> >>>>> @@ -588,6 +611,8 @@ void drm_mode_config_validate(struct
> >> drm_device *dev)
> >>>>> drm_for_each_encoder(encoder, dev)
> >>>>> fixup_encoder_possible_clones(encoder);
> >>>>>
> >>>>> - drm_for_each_encoder(encoder, dev)
> >>>>> + drm_for_each_encoder(encoder, dev) {
> >>>>> validate_encoder_possible_clones(encoder);
> >>>>> + validate_encoder_possible_crtcs(encoder);
> >>>>> + }
> >>>>> }
> >>>>> diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h
> >>>>> index 3741963b9587..b236269f41ac 100644
> >>>>> --- a/include/drm/drm_encoder.h
> >>>>> +++ b/include/drm/drm_encoder.h
> >>>>> @@ -142,7 +142,7 @@ struct drm_encoder {
> >>>>> * the bits for all &drm_crtc objects this encoder can be
> >>>>> connected to
> >>>>> * before calling drm_dev_register().
> >>>>> *
> >>>>> - * In reality almost every driver gets this wrong.
> >>>>> + * You will get a WARN if you get this wrong in the driver.
> >>>>> *
> >>>>> * Note that since CRTC objects can't be hotplugged the assigned
> >> indices
> >>>>> * are stable and hence known before registering all objects.
> >>>>> --
> >>>>> 2.24.1
> >>>>>
> >>>>
> >>>
> >>> Triggers on an Advantech AIMB-228 (R1505G, 3 DP outputs):
> >>
> >> Adding amdgpu display folks.
> >
> > I took a quick look at this and it looks like we limit the number of crtcs
> > later in the mode init process if the number of physical displays can't
> > actually use more crtcs. E.g., the physical board configuration would only
> > allow for 3 active displays even if the hardware technically supports 4
> > crtcs. I presume that way we can just leave the additional hardware power
> > gated all the time.
> >
>
> So, will this be fixed any time soon? I don't feel qualified writing
> such a patch but I would obviously be happy to test one.
It's harmless, but I'll send out a patch soon.
Alex
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
