drm: Validate encoder->possible_crtcs

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 <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211162208.16224-7-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2020-02-11 18:22:07 +02:00
parent 74d2aacbe8
commit 0df1082374
2 changed files with 27 additions and 2 deletions

View File

@ -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);
}
}

View File

@ -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.