| Message ID | 20200211162208.16224-6-ville.syrjala@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: Try to fix encoder possible_clones/crtc | expand |
On Tue, Feb 11, 2020 at 06:22:06PM +0200, Ville Syrjala wrote: > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Many drivers are populating encoder->possible_clones wrong. Let's > persuade them to get it right by adding some loud WARNs. > > We'll cross check the bits between any two encoders. So either > both encoders can clone with the other, or neither can. > > We'll also complain about effectively empty possible_clones, and > possible_clones containing bits for encoders that don't exist. > > v2: encoder->possible_clones now includes the encoder itelf > v3: Move to drm_mode_config_validate() (Daniel) > Document that you get a WARN when this is wrong (Daniel) > Extract full_encoder_mask() > > Acked-by: Thomas Zimmermann <tzimmermann@suse.de> > Cc: Daniel Vetter <daniel@ffwll.ch> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> I wonder whether we should start to have some unit tests for stuff like this, like set up broken driver, make sure we have a WARN in dmesg. But ideally we'd do that with the mocking stuff Kunit hopefully has soon. </idle musings> > --- > drivers/gpu/drm/drm_mode_config.c | 40 +++++++++++++++++++++++++++++++ > include/drm/drm_encoder.h | 2 ++ > 2 files changed, 42 insertions(+) > > diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c > index 75e357c7e84d..afc91447293a 100644 > --- a/drivers/gpu/drm/drm_mode_config.c > +++ b/drivers/gpu/drm/drm_mode_config.c > @@ -533,6 +533,17 @@ void drm_mode_config_cleanup(struct drm_device *dev) > } > EXPORT_SYMBOL(drm_mode_config_cleanup); > > +static u32 full_encoder_mask(struct drm_device *dev) > +{ > + struct drm_encoder *encoder; > + u32 encoder_mask = 0; > + > + drm_for_each_encoder(encoder, dev) > + encoder_mask |= drm_encoder_mask(encoder); > + > + return encoder_mask; > +} > + > /* > * For some reason we want the encoder itself included in > * possible_clones. Make life easy for drivers by allowing them > @@ -544,10 +555,39 @@ static void fixup_encoder_possible_clones(struct drm_encoder *encoder) > encoder->possible_clones = drm_encoder_mask(encoder); > } > > +static void validate_encoder_possible_clones(struct drm_encoder *encoder) > +{ > + struct drm_device *dev = encoder->dev; > + u32 encoder_mask = full_encoder_mask(dev); > + struct drm_encoder *other; > + > + drm_for_each_encoder(other, dev) { > + WARN(!(encoder->possible_clones & drm_encoder_mask(other)) != > + !(other->possible_clones & drm_encoder_mask(encoder)), Bikeshed: !! as canonical "make this a bool value" might be slightly clearer, but whatever. > + "possible_clones mismatch: " > + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x vs. " > + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x\n", > + encoder->base.id, encoder->name, > + drm_encoder_mask(encoder), encoder->possible_clones, > + other->base.id, other->name, > + drm_encoder_mask(other), other->possible_clones); > + } > + > + WARN((encoder->possible_clones & drm_encoder_mask(encoder)) == 0 || > + (encoder->possible_clones & ~encoder_mask) != 0, > + "Bogus possible_clones: " > + "[ENCODER:%d:%s] possible_clones=0x%x (full encoder mask=0x%x)\n", > + encoder->base.id, encoder->name, > + encoder->possible_clones, encoder_mask); > +} Since it's next to each another double-checking that the fixup did add the self-clone is probably too much :-) > + > void drm_mode_config_validate(struct drm_device *dev) > { > struct drm_encoder *encoder; > > drm_for_each_encoder(encoder, dev) > fixup_encoder_possible_clones(encoder); > + > + drm_for_each_encoder(encoder, dev) > + validate_encoder_possible_clones(encoder); > } > diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h > index 22d6cdf729f1..3741963b9587 100644 > --- a/include/drm/drm_encoder.h > +++ b/include/drm/drm_encoder.h > @@ -163,6 +163,8 @@ struct drm_encoder { > * any cloning it can leave @possible_clones set to 0. The core will > * automagically fix this up by setting the bit for the encoder itself. > * > + * You will get a WARN if you get this wrong in the driver. Nice. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > + * > * Note that since encoder objects can't be hotplugged the assigned indices > * are stable and hence known before registering all objects. > */ > -- > 2.24.1 >
On Tue, Feb 11, 2020 at 06:02:33PM +0100, Daniel Vetter wrote: > On Tue, Feb 11, 2020 at 06:22:06PM +0200, Ville Syrjala wrote: > > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > > > Many drivers are populating encoder->possible_clones wrong. Let's > > persuade them to get it right by adding some loud WARNs. > > > > We'll cross check the bits between any two encoders. So either > > both encoders can clone with the other, or neither can. > > > > We'll also complain about effectively empty possible_clones, and > > possible_clones containing bits for encoders that don't exist. > > > > v2: encoder->possible_clones now includes the encoder itelf > > v3: Move to drm_mode_config_validate() (Daniel) > > Document that you get a WARN when this is wrong (Daniel) > > Extract full_encoder_mask() > > > > Acked-by: Thomas Zimmermann <tzimmermann@suse.de> > > Cc: Daniel Vetter <daniel@ffwll.ch> > > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > > I wonder whether we should start to have some unit tests for stuff like > this, like set up broken driver, make sure we have a WARN in dmesg. But > ideally we'd do that with the mocking stuff Kunit hopefully has soon. > > </idle musings> > > > > --- > > drivers/gpu/drm/drm_mode_config.c | 40 +++++++++++++++++++++++++++++++ > > include/drm/drm_encoder.h | 2 ++ > > 2 files changed, 42 insertions(+) > > > > diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c > > index 75e357c7e84d..afc91447293a 100644 > > --- a/drivers/gpu/drm/drm_mode_config.c > > +++ b/drivers/gpu/drm/drm_mode_config.c > > @@ -533,6 +533,17 @@ void drm_mode_config_cleanup(struct drm_device *dev) > > } > > EXPORT_SYMBOL(drm_mode_config_cleanup); > > > > +static u32 full_encoder_mask(struct drm_device *dev) > > +{ > > + struct drm_encoder *encoder; > > + u32 encoder_mask = 0; > > + > > + drm_for_each_encoder(encoder, dev) > > + encoder_mask |= drm_encoder_mask(encoder); > > + > > + return encoder_mask; > > +} > > + > > /* > > * For some reason we want the encoder itself included in > > * possible_clones. Make life easy for drivers by allowing them > > @@ -544,10 +555,39 @@ static void fixup_encoder_possible_clones(struct drm_encoder *encoder) > > encoder->possible_clones = drm_encoder_mask(encoder); > > } > > > > +static void validate_encoder_possible_clones(struct drm_encoder *encoder) > > +{ > > + struct drm_device *dev = encoder->dev; > > + u32 encoder_mask = full_encoder_mask(dev); > > + struct drm_encoder *other; > > + > > + drm_for_each_encoder(other, dev) { > > + WARN(!(encoder->possible_clones & drm_encoder_mask(other)) != > > + !(other->possible_clones & drm_encoder_mask(encoder)), > > Bikeshed: !! as canonical "make this a bool value" might be slightly > clearer, but whatever. Can repaint. > > > + "possible_clones mismatch: " > > + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x vs. " > > + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x\n", > > + encoder->base.id, encoder->name, > > + drm_encoder_mask(encoder), encoder->possible_clones, > > + other->base.id, other->name, > > + drm_encoder_mask(other), other->possible_clones); > > + } > > + > > + WARN((encoder->possible_clones & drm_encoder_mask(encoder)) == 0 || > > + (encoder->possible_clones & ~encoder_mask) != 0, > > + "Bogus possible_clones: " > > + "[ENCODER:%d:%s] possible_clones=0x%x (full encoder mask=0x%x)\n", > > + encoder->base.id, encoder->name, > > + encoder->possible_clones, encoder_mask); > > +} > > Since it's next to each another double-checking that the fixup did add the > self-clone is probably too much :-) I changed the fixup to be just if (possible_clones == 0) possible_clones = drm_encoder_mask(); So if the driver tries to set it up but fails and forgets the encoder itself this WARN will still trip. > > > + > > void drm_mode_config_validate(struct drm_device *dev) > > { > > struct drm_encoder *encoder; > > > > drm_for_each_encoder(encoder, dev) > > fixup_encoder_possible_clones(encoder); > > + > > + drm_for_each_encoder(encoder, dev) > > + validate_encoder_possible_clones(encoder); > > > } > > diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h > > index 22d6cdf729f1..3741963b9587 100644 > > --- a/include/drm/drm_encoder.h > > +++ b/include/drm/drm_encoder.h > > @@ -163,6 +163,8 @@ struct drm_encoder { > > * any cloning it can leave @possible_clones set to 0. The core will > > * automagically fix this up by setting the bit for the encoder itself. > > * > > + * You will get a WARN if you get this wrong in the driver. > > Nice. > > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > > > + * > > * Note that since encoder objects can't be hotplugged the assigned indices > > * are stable and hence known before registering all objects. > > */ > > -- > > 2.24.1 > > > > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch
On Tue, Feb 11, 2020 at 07:13:31PM +0200, Ville Syrjälä wrote: > On Tue, Feb 11, 2020 at 06:02:33PM +0100, Daniel Vetter wrote: > > On Tue, Feb 11, 2020 at 06:22:06PM +0200, Ville Syrjala wrote: > > > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > > > > > Many drivers are populating encoder->possible_clones wrong. Let's > > > persuade them to get it right by adding some loud WARNs. > > > > > > We'll cross check the bits between any two encoders. So either > > > both encoders can clone with the other, or neither can. > > > > > > We'll also complain about effectively empty possible_clones, and > > > possible_clones containing bits for encoders that don't exist. > > > > > > v2: encoder->possible_clones now includes the encoder itelf > > > v3: Move to drm_mode_config_validate() (Daniel) > > > Document that you get a WARN when this is wrong (Daniel) > > > Extract full_encoder_mask() > > > > > > Acked-by: Thomas Zimmermann <tzimmermann@suse.de> > > > Cc: Daniel Vetter <daniel@ffwll.ch> > > > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > > > > I wonder whether we should start to have some unit tests for stuff like > > this, like set up broken driver, make sure we have a WARN in dmesg. But > > ideally we'd do that with the mocking stuff Kunit hopefully has soon. > > > > </idle musings> > > > > > > > --- > > > drivers/gpu/drm/drm_mode_config.c | 40 +++++++++++++++++++++++++++++++ > > > include/drm/drm_encoder.h | 2 ++ > > > 2 files changed, 42 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c > > > index 75e357c7e84d..afc91447293a 100644 > > > --- a/drivers/gpu/drm/drm_mode_config.c > > > +++ b/drivers/gpu/drm/drm_mode_config.c > > > @@ -533,6 +533,17 @@ void drm_mode_config_cleanup(struct drm_device *dev) > > > } > > > EXPORT_SYMBOL(drm_mode_config_cleanup); > > > > > > +static u32 full_encoder_mask(struct drm_device *dev) > > > +{ > > > + struct drm_encoder *encoder; > > > + u32 encoder_mask = 0; > > > + > > > + drm_for_each_encoder(encoder, dev) > > > + encoder_mask |= drm_encoder_mask(encoder); > > > + > > > + return encoder_mask; > > > +} > > > + > > > /* > > > * For some reason we want the encoder itself included in > > > * possible_clones. Make life easy for drivers by allowing them > > > @@ -544,10 +555,39 @@ static void fixup_encoder_possible_clones(struct drm_encoder *encoder) > > > encoder->possible_clones = drm_encoder_mask(encoder); > > > } > > > > > > +static void validate_encoder_possible_clones(struct drm_encoder *encoder) > > > +{ > > > + struct drm_device *dev = encoder->dev; > > > + u32 encoder_mask = full_encoder_mask(dev); > > > + struct drm_encoder *other; > > > + > > > + drm_for_each_encoder(other, dev) { > > > + WARN(!(encoder->possible_clones & drm_encoder_mask(other)) != > > > + !(other->possible_clones & drm_encoder_mask(encoder)), > > > > Bikeshed: !! as canonical "make this a bool value" might be slightly > > clearer, but whatever. > > Can repaint. > > > > > > + "possible_clones mismatch: " > > > + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x vs. " > > > + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x\n", > > > + encoder->base.id, encoder->name, > > > + drm_encoder_mask(encoder), encoder->possible_clones, > > > + other->base.id, other->name, > > > + drm_encoder_mask(other), other->possible_clones); > > > + } > > > + > > > + WARN((encoder->possible_clones & drm_encoder_mask(encoder)) == 0 || > > > + (encoder->possible_clones & ~encoder_mask) != 0, > > > + "Bogus possible_clones: " > > > + "[ENCODER:%d:%s] possible_clones=0x%x (full encoder mask=0x%x)\n", > > > + encoder->base.id, encoder->name, > > > + encoder->possible_clones, encoder_mask); > > > +} > > > > Since it's next to each another double-checking that the fixup did add the > > self-clone is probably too much :-) > > I changed the fixup to be just > if (possible_clones == 0) > possible_clones = drm_encoder_mask(); > > So if the driver tries to set it up but fails and forgets the > encoder itself this WARN will still trip. Duh, I was just blind, everything is looking good. -Daniel > > > > > > + > > > void drm_mode_config_validate(struct drm_device *dev) > > > { > > > struct drm_encoder *encoder; > > > > > > drm_for_each_encoder(encoder, dev) > > > fixup_encoder_possible_clones(encoder); > > > + > > > + drm_for_each_encoder(encoder, dev) > > > + validate_encoder_possible_clones(encoder); > > > > > } > > > diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h > > > index 22d6cdf729f1..3741963b9587 100644 > > > --- a/include/drm/drm_encoder.h > > > +++ b/include/drm/drm_encoder.h > > > @@ -163,6 +163,8 @@ struct drm_encoder { > > > * any cloning it can leave @possible_clones set to 0. The core will > > > * automagically fix this up by setting the bit for the encoder itself. > > > * > > > + * You will get a WARN if you get this wrong in the driver. > > > > Nice. > > > > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > > > > > + * > > > * Note that since encoder objects can't be hotplugged the assigned indices > > > * are stable and hence known before registering all objects. > > > */ > > > -- > > > 2.24.1 > > > > > > > -- > > Daniel Vetter > > Software Engineer, Intel Corporation > > http://blog.ffwll.ch > > -- > Ville Syrjälä > Intel
diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c index 75e357c7e84d..afc91447293a 100644 --- a/drivers/gpu/drm/drm_mode_config.c +++ b/drivers/gpu/drm/drm_mode_config.c @@ -533,6 +533,17 @@ void drm_mode_config_cleanup(struct drm_device *dev) } EXPORT_SYMBOL(drm_mode_config_cleanup); +static u32 full_encoder_mask(struct drm_device *dev) +{ + struct drm_encoder *encoder; + u32 encoder_mask = 0; + + drm_for_each_encoder(encoder, dev) + encoder_mask |= drm_encoder_mask(encoder); + + return encoder_mask; +} + /* * For some reason we want the encoder itself included in * possible_clones. Make life easy for drivers by allowing them @@ -544,10 +555,39 @@ static void fixup_encoder_possible_clones(struct drm_encoder *encoder) encoder->possible_clones = drm_encoder_mask(encoder); } +static void validate_encoder_possible_clones(struct drm_encoder *encoder) +{ + struct drm_device *dev = encoder->dev; + u32 encoder_mask = full_encoder_mask(dev); + struct drm_encoder *other; + + drm_for_each_encoder(other, dev) { + WARN(!(encoder->possible_clones & drm_encoder_mask(other)) != + !(other->possible_clones & drm_encoder_mask(encoder)), + "possible_clones mismatch: " + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x vs. " + "[ENCODER:%d:%s] mask=0x%x possible_clones=0x%x\n", + encoder->base.id, encoder->name, + drm_encoder_mask(encoder), encoder->possible_clones, + other->base.id, other->name, + drm_encoder_mask(other), other->possible_clones); + } + + WARN((encoder->possible_clones & drm_encoder_mask(encoder)) == 0 || + (encoder->possible_clones & ~encoder_mask) != 0, + "Bogus possible_clones: " + "[ENCODER:%d:%s] possible_clones=0x%x (full encoder mask=0x%x)\n", + encoder->base.id, encoder->name, + encoder->possible_clones, encoder_mask); +} + void drm_mode_config_validate(struct drm_device *dev) { struct drm_encoder *encoder; drm_for_each_encoder(encoder, dev) fixup_encoder_possible_clones(encoder); + + drm_for_each_encoder(encoder, dev) + validate_encoder_possible_clones(encoder); } diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h index 22d6cdf729f1..3741963b9587 100644 --- a/include/drm/drm_encoder.h +++ b/include/drm/drm_encoder.h @@ -163,6 +163,8 @@ struct drm_encoder { * any cloning it can leave @possible_clones set to 0. The core will * automagically fix this up by setting the bit for the encoder itself. * + * You will get a WARN if you get this wrong in the driver. + * * Note that since encoder objects can't be hotplugged the assigned indices * are stable and hence known before registering all objects. */