> -----Original Message----- > From: amd-gfx [mailto:amd-gfx-bounces at lists.freedesktop.org] On Behalf > Of Michel Dänzer > Sent: Friday, August 18, 2017 1:54 AM > To: amd-gfx at lists.freedesktop.org > Subject: [PATCH xf86-video-ati] modesetting: re-set the crtc's mode when > link-status goes BAD > > From: Martin Peres <martin.peres at linux.intel.com> > > Despite all the careful planning of the kernel, a link may become > insufficient to handle the currently-set mode. At this point, the > kernel should mark this particular configuration as being broken > and potentially prune the mode before setting the offending connector's > link-status to BAD and send the userspace a hotplug event. This may > happen right after a modeset or later on. > > Upon receiving a hot-plug event, we iterate through the connectors to > re-apply the currently-set mode on all the connectors that have a > link-status property set to BAD. The kernel may be able to get the > link to work by dropping to using a lower link bpp (with the same > display bpp). However, the modeset may fail if the kernel has pruned > the mode, so to make users aware of this problem a warning is outputed > in the logs to warn about having a potentially-black display. > > This patch does not modify the current behaviour of always propagating > the events to the randr clients. This allows desktop environments to > re-probe the connectors and select a new resolution based on the new > (currated) mode list if a mode disapeared. This behaviour is expected in > order to pass the Display Port compliance tests. > > (Ported from xserver commit > bcee1b76aa0db8525b491485e90b8740763d7de6) > > [ Michel: Bump libdrm dependency to >= 2.4.78 for > DRM_MODE_LINK_STATUS_BAD ] > > Signed-off-by: Michel Dänzer <michel.daenzer at amd.com> Reviewed-by: Alex Deucher <alexander.deucher at amd.com> > --- > configure.ac | 2 +- > src/drmmode_display.c | 43 > +++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+), 1 deletion(-) > > diff --git a/configure.ac b/configure.ac > index c9bc0a958..170f42ef7 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -70,7 +70,7 @@ XORG_DRIVER_CHECK_EXT(XV, videoproto) > XORG_DRIVER_CHECK_EXT(DPMSExtension, xextproto) > > # Checks for libraries. > -PKG_CHECK_MODULES(LIBDRM, [libdrm >= 2.4.60]) > +PKG_CHECK_MODULES(LIBDRM, [libdrm >= 2.4.78]) > PKG_CHECK_MODULES(LIBDRM_RADEON, [libdrm_radeon]) > > # Obtain compiler/linker options for the driver dependencies > diff --git a/src/drmmode_display.c b/src/drmmode_display.c > index 4839b415c..f926bc018 100644 > --- a/src/drmmode_display.c > +++ b/src/drmmode_display.c > @@ -2826,6 +2826,49 @@ radeon_mode_hotplug(ScrnInfoPtr scrn, > drmmode_ptr drmmode) > Bool changed = FALSE; > int num_dvi = 0, num_hdmi = 0; > > + /* Try to re-set the mode on all the connectors with a BAD link-state: > + * This may happen if a link degrades and a new modeset is > necessary, using > + * different link-training parameters. If the kernel found that the > current > + * mode is not achievable anymore, it should have pruned the mode > before > + * sending the hotplug event. Try to re-set the currently-set mode to > keep > + * the display alive, this will fail if the mode has been pruned. > + * In any case, we will send randr events for the Desktop > Environment to > + * deal with it, if it wants to. > + */ > + for (i = 0; i < config->num_output; i++) { > + xf86OutputPtr output = config->output[i]; > + drmmode_output_private_ptr drmmode_output = output- > >driver_private; > + uint32_t con_id = drmmode_output->mode_output- > >connector_id; > + drmModeConnectorPtr koutput; > + > + /* Get an updated view of the properties for the current > connector and > + * look for the link-status property > + */ > + koutput = drmModeGetConnectorCurrent(pRADEONEnt- > >fd, con_id); > + for (j = 0; koutput && j < koutput->count_props; j++) { > + drmModePropertyPtr props; > + props = drmModeGetProperty(pRADEONEnt->fd, > koutput->props[j]); > + if (props && props->flags & > DRM_MODE_PROP_ENUM && > + !strcmp(props->name, "link-status") && > + koutput->prop_values[j] == > DRM_MODE_LINK_STATUS_BAD) { > + xf86CrtcPtr crtc = output->crtc; > + if (!crtc) > + continue; > + > + /* the connector got a link failure, re-set the > current mode */ > + drmmode_set_mode_major(crtc, &crtc- > >mode, crtc->rotation, > + crtc->x, crtc->y); > + > + xf86DrvMsg(scrn->scrnIndex, X_WARNING, > + "hotplug event: connector %u's link- > state is BAD, " > + "tried resetting the current mode. > You may be left " > + "with a black screen if this fails...\n", > con_id); > + } > + drmModeFreeProperty(props); > + } > + drmModeFreeConnector(koutput); > + } > + > mode_res = drmModeGetResources(pRADEONEnt->fd); > if (!mode_res) > goto out; > -- > 2.14.1 > > _______________________________________________ > amd-gfx mailing list > amd-gfx at lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/amd-gfx
