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); } void intel_fbdev_initial_config_async(struct drm_device *dev) -- 2.17.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
