On Wed, 2018-04-18 at 00:44 +0100, Chris Wilson wrote: > Quoting José Roberto de Souza (2018-04-17 23:34:18) > > If the initial fbdev configuration(intel_fbdev_initial_config()) > > runs and > > there still no sink connected it will cause > > drm_fb_helper_initial_config() to return 0 as no error happened(but > > internally the return is -EAGAIN). > > Because no framebuffer was allocated, when a sink is connected > > intel_fbdev_output_poll_changed() will not execute > > drm_fb_helper_hotplug_event() that would trigger another try to do > > the > > initial fbdev configuration. > > > > So here creating a dummy framebuffer of 800x600, so > > drm_fb_helper_hotplug_event() will be executed and fbdev can be > > properly > > setup when a sink is connected, if needed the dummy framebuffer > > will be > > freed and a new with the proper size will be allocated. > > > > This issue also happens when a MST DP sink is connected since boot, > > as > > the MST topology is discovered in parallel if > > intel_fbdev_initial_config() > > is executed before the first sink MST is discovered it will cause > > this > > same issue. > > > > This is a follow up patch of > > https://patchwork.freedesktop.org/patch/196089/ > > > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104158 > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104425 > > Cc: Chris Wilson <ch...@chris-wilson.co.uk> > > Cc: Rodrigo Vivi <rodrigo.v...@intel.com> > > Signed-off-by: José Roberto de Souza <jose.so...@intel.com> > > --- > > drivers/gpu/drm/i915/intel_fbdev.c | 24 +++++++++++++++++++++++- > > 1 file changed, 23 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_fbdev.c > > b/drivers/gpu/drm/i915/intel_fbdev.c > > index 7d41d139341b..773577d39782 100644 > > --- a/drivers/gpu/drm/i915/intel_fbdev.c > > +++ b/drivers/gpu/drm/i915/intel_fbdev.c > > @@ -696,14 +696,36 @@ int intel_fbdev_init(struct drm_device *dev) > > return 0; > > } > > > > +static void intel_fbdev_dummy_fb_create(struct intel_fbdev > > *ifbdev) > > +{ > > + struct drm_fb_helper_surface_size sizes; > > + > > + sizes.fb_width = 800; > > + sizes.fb_height = 600; > > + sizes.surface_width = sizes.fb_width; > > + sizes.surface_height = sizes.fb_height; > > + sizes.surface_bpp = 32; > > + sizes.surface_depth = 24; > > + > > + if (intelfb_create(&ifbdev->helper, &sizes)) > > + DRM_ERROR("Unable to create dummy framebufer"); > > +} > > + > > static void intel_fbdev_initial_config(void *data, async_cookie_t > > cookie) > > { > > struct intel_fbdev *ifbdev = data; > > > > /* Due to peculiar init order wrt to hpd handling this is > > separate. */ > > if (drm_fb_helper_initial_config(&ifbdev->helper, > > - ifbdev->preferred_bpp)) > > + ifbdev->preferred_bpp)) { > > intel_fbdev_unregister(to_i915(ifbdev- > > >helper.dev)); > > + return; > > + } > > + > > + mutex_lock(&ifbdev->helper.lock); > > + if (!ifbdev->vma) > > + intel_fbdev_dummy_fb_create(ifbdev); > > + mutex_unlock(&ifbdev->helper.lock); > > } > > Did you try > > diff --git a/drivers/gpu/drm/i915/intel_fbdev.c > b/drivers/gpu/drm/i915/intel_fbdev.c > index 65a3313723c9..4120c635742d 100644 > --- a/drivers/gpu/drm/i915/intel_fbdev.c > +++ b/drivers/gpu/drm/i915/intel_fbdev.c > @@ -493,6 +493,7 @@ static bool intel_fb_initial_config(struct > drm_fb_helper *fb_helper, > bail: > DRM_DEBUG_KMS("Not using firmware configuration\n"); > memcpy(enabled, save_enabled, count); > + fb_helper->deferred_setup = true;
This is too earlier to set deferred_setup when intel_fb_initial_config() fails, __drm_fb_helper_initial_config_and_unlock() will then try to probe/create a fb but as there is no sink connected it will fail too. Also __drm_fb_helper_initial_config_and_unlock() is already setting deferred_setup if both attempts fails. > ret = false; > } > > possible as of > > commit ca91a2758fcef6635626993557dd51cfbb6dd134 > Author: Daniel Vetter <daniel.vet...@ffwll.ch> > Date: Thu Jul 6 15:00:21 2017 +0200 > > drm/fb-helper: Support deferred setup > > FB helper code falls back to a 1024x768 mode if no outputs are > connected > or don't report back any modes upon initialization. This can be > annoying > because outputs that are added to FB helper later on can't be > used with > FB helper if they don't support a matching mode. > ... > > -Chris > _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
