Hi Marek. On Thu, Aug 27, 2020 at 01:39:06PM +0200, Marek Szyprowski wrote: > Hi Sam, > > On 26.07.2020 22:33, Sam Ravnborg wrote: > > Prepare the tc358764 bridge driver for use in a chained setup by > > replacing direct use of drm_panel with drm_panel_bridge support. > > > > The bridge panel will use the connector type reported by the panel, > > where the connector for this driver hardcodes DRM_MODE_CONNECTOR_LVDS. > > > > The tc358764 did not any additional info the the connector so the > > connector creation is passed to the bridge panel driver. > > > > v3: > > - Merge with patch to make connector creation optional to avoid > > creating two connectors (Laurent) > > - Pass connector creation to bridge panel, as this bridge driver > > did not add any extra info to the connector. > > - Set bridge.type to DRM_MODE_CONNECTOR_LVDS. > > > > v2: > > - Use PTR_ERR_OR_ZERO() (kbuild test robot) > > > > Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx> > > Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > > Cc: kbuild test robot <lkp@xxxxxxxxx> > > Cc: Andrzej Hajda <a.hajda@xxxxxxxxxxx> > > Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx> > > Cc: Jonas Karlman <jonas@xxxxxxxxx> > > Cc: Jernej Skrabec <jernej.skrabec@xxxxxxxx> > > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > > I've noticed that this patch has been merged recently to linux-next. > Sadly it causes regression on Samsung Exynos5250-based Arndale board. Thanks for reporting this! I did not find time to focus on this bug this weekend. It is on my todo list for the coming weekend. Anything you could do to narrow down this a bit to help finding the root cause? Ideas: - Trying to find out what part of the connector that cuases troubles - Posting the full kernel boot log, to help identifying something. Bonus if we get a working and non-working log - so we can compare. - Migrate exonys to the new model That would not fix the bug, so that would be a natural step 2 - Identify the exact code-patch in the exonys driver that is used. drm_bridge_attach() is called in several places - And likely much more that I just forgot Any help would be appreciated - I did not find the culprint from first glance. I may still be obvious but I just failed to spot it. Sam > > It can be observed by the following warning during boot: > > ------------[ cut here ]------------ > WARNING: CPU: 1 PID: 1 at drivers/gpu/drm/drm_atomic_state_helper.c:494 > drm_atomic_helper_connector_duplicate_state+0x60/0x68 > Modules linked in: > CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc2-00501-g1644127f83bc > #1526 > Hardware name: Samsung Exynos (Flattened Device Tree) > [<c011184c>] (unwind_backtrace) from [<c010d250>] (show_stack+0x10/0x14) > [<c010d250>] (show_stack) from [<c0517ce4>] (dump_stack+0xbc/0xe8) > [<c0517ce4>] (dump_stack) from [<c01270a8>] (__warn+0xf0/0x108) > [<c01270a8>] (__warn) from [<c0127170>] (warn_slowpath_fmt+0xb0/0xb8) > [<c0127170>] (warn_slowpath_fmt) from [<c05e81f0>] > (drm_atomic_helper_connector_duplicate_state+0x60/0x68) > [<c05e81f0>] (drm_atomic_helper_connector_duplicate_state) from > [<c06014b8>] (drm_atomic_get_connector_state+0xfc/0x184) > [<c06014b8>] (drm_atomic_get_connector_state) from [<c0602238>] > (__drm_atomic_helper_set_config+0x2a0/0x368) > [<c0602238>] (__drm_atomic_helper_set_config) from [<c06183b8>] > (drm_client_modeset_commit_atomic+0x180/0x284) > [<c06183b8>] (drm_client_modeset_commit_atomic) from [<c061859c>] > (drm_client_modeset_commit_locked+0x64/0x1cc) > [<c061859c>] (drm_client_modeset_commit_locked) from [<c0618728>] > (drm_client_modeset_commit+0x24/0x40) > [<c0618728>] (drm_client_modeset_commit) from [<c05eb6b4>] > (drm_fb_helper_restore_fbdev_mode_unlocked+0x50/0x94) > [<c05eb6b4>] (drm_fb_helper_restore_fbdev_mode_unlocked) from > [<c05eb728>] (drm_fb_helper_set_par+0x30/0x5c) > [<c05eb728>] (drm_fb_helper_set_par) from [<c055dedc>] > (fbcon_init+0x5c8/0x65c) > [<c055dedc>] (fbcon_init) from [<c05a8530>] (visual_init+0xc0/0x108) > [<c05a8530>] (visual_init) from [<c05aaca4>] > (do_bind_con_driver+0x180/0x39c) > [<c05aaca4>] (do_bind_con_driver) from [<c05ab244>] > (do_take_over_console+0x140/0x1cc) > [<c05ab244>] (do_take_over_console) from [<c055ac04>] > (do_fbcon_takeover+0x84/0xe0) > [<c055ac04>] (do_fbcon_takeover) from [<c0553820>] > (register_framebuffer+0x1cc/0x2dc) > [<c0553820>] (register_framebuffer) from [<c05eb19c>] > (__drm_fb_helper_initial_config_and_unlock+0x3f0/0x5e8) > [<c05eb19c>] (__drm_fb_helper_initial_config_and_unlock) from > [<c05d941c>] (drm_kms_helper_hotplug_event+0x24/0x30) > [<c05d941c>] (drm_kms_helper_hotplug_event) from [<c0628f74>] > (exynos_dsi_host_attach+0x184/0x2d8) > [<c0628f74>] (exynos_dsi_host_attach) from [<c0634120>] > (tc358764_probe+0x13c/0x1ac) > [<c0634120>] (tc358764_probe) from [<c064cce4>] (really_probe+0x200/0x48c) > [<c064cce4>] (really_probe) from [<c064d0d8>] > (driver_probe_device+0x78/0x1fc) > [<c064d0d8>] (driver_probe_device) from [<c064d4c0>] > (device_driver_attach+0x58/0x60) > [<c064d4c0>] (device_driver_attach) from [<c064d5a4>] > (__driver_attach+0xdc/0x174) > [<c064d5a4>] (__driver_attach) from [<c064aaf0>] > (bus_for_each_dev+0x68/0xb4) > [<c064aaf0>] (bus_for_each_dev) from [<c064be24>] > (bus_add_driver+0x158/0x214) > [<c064be24>] (bus_add_driver) from [<c064e478>] (driver_register+0x78/0x110) > [<c064e478>] (driver_register) from [<c0102378>] > (do_one_initcall+0x8c/0x424) > [<c0102378>] (do_one_initcall) from [<c1001158>] > (kernel_init_freeable+0x190/0x204) > [<c1001158>] (kernel_init_freeable) from [<c0ab835c>] > (kernel_init+0x8/0x118) > [<c0ab835c>] (kernel_init) from [<c0100114>] (ret_from_fork+0x14/0x20) > Exception stack(0xee8ddfb0 to 0xee8ddff8) > dfa0: 00000000 00000000 00000000 > 00000000 > dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > 00000000 > dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 > irq event stamp: 171647 > hardirqs last enabled at (171653): [<c019ec00>] vprintk_emit+0x2ac/0x2ec > hardirqs last disabled at (171658): [<c019eab8>] vprintk_emit+0x164/0x2ec > softirqs last enabled at (171486): [<c010174c>] __do_softirq+0x50c/0x608 > softirqs last disabled at (171473): [<c0130340>] irq_exit+0x168/0x16c > ---[ end trace 33117a16f066466a ]--- > > Then calling modetest end with segmentation fault. I'm not able to check > currently if there is anything on the display because of having only > remote access to the board. If this is important I will try to ask > someone to help checking at the board's display at the office. > > Best regards > -- > Marek Szyprowski, PhD > Samsung R&D Institute Poland _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
