kernel/linux.git/drivers/gpu/drm/drm_debugfs.c, branch v6.1.168

drm/edid: Handle EDID 1.4 range descriptor h/vfreq offsets

2022-09-02T13:38:51+00:00

EDID 1.4 introduced some extra flags in the range descriptor to support min/max h/vfreq >= 255. Consult them to correctly parse the vfreq limits. Note that some combinations of the flags are documented as "reserved" (as are some other values in the descriptor) but explicitly checking for those doesn't seem particularly worthwile since we end up with bogus results whether we decode them or not. v2: Increase the storage to u16 to make it work (Jani) Note the "reserved" values situation (Jani) v3: Document the EDID version number in the defines Drop some bogus (u8) casts Cc: stable@vger.kernel.org Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6519 References: https://gitlab.freedesktop.org/drm/intel/-/issues/6484 Reviewed-by: Jani Nikula Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220826213501.31490-2-ville.syrjala@linux.intel.com Reviewed-by: Manasi Navare

drm/edid: abstract debugfs override EDID set/reset

2022-06-30T07:50:59+00:00

Add functions drm_edid_override_set() and drm_edid_override_reset() to support "edid_override" connector debugfs, and to hide the details about it in drm_edid.c. No functional changes at this time. Also note in the connector.override_edid flag kernel-doc that this is only supposed to be modified by the code doing debugfs EDID override handling. Currently, it is still being modified by amdgpu in create_eml_sink() and handle_edid_mgmt() for reasons unknown. This was added in commit 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)") and later moved to amdgpu_dm.c in commit e7b07ceef2a6 ("drm/amd/display: Merge amdgpu_dm_types and amdgpu_dm"). Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/8f6b4001630cafac5f44aa5913429ac9979743d2.1656494768.git.jani.nikula@intel.com

drm/debug: Expose connector's max supported bpc via debugfs

2022-05-23T08:27:36+00:00

It's useful to know the connector's max supported bpc for IGT testing. Expose it via a debugfs file on the connector "output_bpc". Example: cat /sys/kernel/debug/dri/0/DP-1/output_bpc V2: * Fix typo in comments (Harry) Cc: Jani Nikula Cc: Ville Syrjälä Cc: Harry Wentland Signed-off-by: Bhanuprakash Modem Reviewed-by: Arun R Murthy Reviewed-by: Harry Wentland Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20220519095149.3560034-2-bhanuprakash.modem@intel.com

drm: Plumb debugfs_init through to panels

2022-02-15T23:25:18+00:00

We'd like panels to be able to add things to debugfs underneath the connector's directory. Let's plumb it through. A panel will be able to put things in a "panel" directory under the connector's directory. Note that debugfs is not ABI and so it's always possible that the location that the panel gets for its debugfs could change in the future. NOTE: this currently only works if you're using a modern architecture. Specifically the plumbing relies on _both_ drm_bridge_connector and drm_panel_bridge. If you're not using one or both of these things then things won't be plumbed through. As a side effect of this change, drm_bridges can also get callbacks to put stuff underneath the connector's debugfs directory. At the moment all bridges in the chain have their debugfs_init() called with the connector's root directory. Signed-off-by: Douglas Anderson Reviewed-by: Javier Martinez Canillas Reviewed-by: Laurent Pinchart Link: https://patchwork.freedesktop.org/patch/msgid/20220204161245.v2.2.Ib0bd5346135cbb0b63006b69b61d4c8af6484740@changeid

drm: avoid blocking in drm_clients_info's rcu section

2021-07-20T18:14:42+00:00

Inside drm_clients_info, the rcu_read_lock is held to lock pid_task()->comm. However, within this protected section, a call to drm_is_current_master is made, which involves a mutex lock in a future patch. However, this is illegal because the mutex lock might block while in the RCU read-side critical section. Since drm_is_current_master isn't protected by rcu_read_lock, we avoid this by moving it out of the RCU critical section. The following report came from intel-gfx ci's igt@debugfs_test@read_all_entries testcase: ============================= [ BUG: Invalid wait context ] 5.13.0-CI-Patchwork_20515+ #1 Tainted: G W ----------------------------- debugfs_test/1101 is trying to lock: ffff888132d901a8 (&dev->master_mutex){+.+.}-{3:3}, at: drm_is_current_master+0x1e/0x50 other info that might help us debug this: context-{4:4} 3 locks held by debugfs_test/1101: #0: ffff88810fdffc90 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0x53/0x3b0 #1: ffff888132d90240 (&dev->filelist_mutex){+.+.}-{3:3}, at: drm_clients_info+0x63/0x2a0 #2: ffffffff82734220 (rcu_read_lock){....}-{1:2}, at: drm_clients_info+0x1b1/0x2a0 stack backtrace: CPU: 8 PID: 1101 Comm: debugfs_test Tainted: G W 5.13.0-CI-Patchwork_20515+ #1 Hardware name: Intel Corporation CometLake Client Platform/CometLake S UDIMM (ERB/CRB), BIOS CMLSFWR1.R00.1263.D00.1906260926 06/26/2019 Call Trace: dump_stack+0x7f/0xad __lock_acquire.cold.78+0x2af/0x2ca lock_acquire+0xd3/0x300 ? drm_is_current_master+0x1e/0x50 ? __mutex_lock+0x76/0x970 ? lockdep_hardirqs_on+0xbf/0x130 __mutex_lock+0xab/0x970 ? drm_is_current_master+0x1e/0x50 ? drm_is_current_master+0x1e/0x50 ? drm_is_current_master+0x1e/0x50 drm_is_current_master+0x1e/0x50 drm_clients_info+0x107/0x2a0 seq_read_iter+0x178/0x3b0 seq_read+0x104/0x150 full_proxy_read+0x4e/0x80 vfs_read+0xa5/0x1b0 ksys_read+0x5a/0xd0 do_syscall_64+0x39/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: Desmond Cheong Zhi Xi Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210712043508.11584-3-desmondcheongzx@gmail.com

drm/debug: Expose connector VRR monitor range via debugfs

2020-06-25T22:47:14+00:00

[Why] It's useful to know the min and max vrr range for IGT testing. [How] Expose the min and max vfreq for the connector via a debugfs file on the connector, "vrr_range". Example usage: cat /sys/kernel/debug/dri/0/DP-1/vrr_range v2: * Fix the typo in max_vfreq (Manasi) * Change the name of node to i915_vrr_info so we can add other vrr info for more debug info (Manasi) * Change the VRR capable to display Yes or No (Manasi) * Fix indentation checkpatch errors (Manasi) v3: * Remove the unnecessary debug print (Manasi) v4: * Rebase v5: * Rename to vrr_range to match AMD debugfs v6: * Rebase (manasi) v7: * Fix cmpilation due to rebase v8: * Move debugfs node creation logic to DRM (Emil) * Remove AMD specific logic (Emil) v9: * Separate patch for removal of AMD specific logic (Manasi) Signed-off-by: Bhanuprakash Modem Signed-off-by: Manasi Navare Cc: Jani Nikula Cc: Ville Syrjälä Cc: Harry Wentland CC: Emil Velikov Reviewed-by: Manasi Navare Signed-off-by: Manasi Navare Link: https://patchwork.freedesktop.org/patch/msgid/20200622142519.16214-3-bhanuprakash.modem@intel.com

drm/debugfs: fix plain echo to connector "force" attribute

2020-05-17T16:27:57+00:00

Using plain echo to set the "force" connector attribute fails with -EINVAL, because echo appends a newline to the output. Replace strcmp with sysfs_streq to also accept strings that end with a newline. v2: use sysfs_streq instead of stripping trailing whitespace Signed-off-by: Michael Tretter Reviewed-by: Jani Nikula Signed-off-by: Emil Velikov Link: https://patchwork.freedesktop.org/patch/msgid/20170817104307.17124-1-m.tretter@pengutronix.de

drm: convert .debugfs_init() hook to return void.

2020-03-18T16:53:28+00:00

As a result of commit 987d65d01356 (drm: debugfs: make drm_debugfs_create_files() never fail) and changes to various debugfs functions in drm/core and across various drivers, there is no need for the drm_driver.debugfs_init() hook to have a return value. Therefore, declare it as void. This also includes refactoring all users of the .debugfs_init() hook to return void across the subsystem. v2: include changes to the hook and drivers that use it in one patch to prevent driver breakage and enable individual successful compilation of this change. References: https://lists.freedesktop.org/archives/dri-devel/2020-February/257183.html Signed-off-by: Wambui Karuga Reviewed-by: Greg Kroah-Hartman Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200310133121.27913-18-wambui.karugax@gmail.com

drm/debugfs: remove checks for return value of drm_debugfs functions.

2020-03-18T16:32:20+00:00

Since 987d65d01356 (drm: debugfs: make drm_debugfs_create_files() never fail), there is no need to check the return value of drm_debugfs_create_files(). Therefore, remove remove unnecessary checks and error handling statement blocks for its return value. These changes also enable changing drm_debugfs_create_files() to return void. Signed-off-by: Wambui Karuga Reviewed-by: Greg Kroah-Hartman Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20200310133121.27913-17-wambui.karugax@gmail.com

drm/debugfs: also take per device driver features into account

2020-01-25T13:49:11+00:00

Use drm_core_check_all_features() to ensure both the driver features and the per-device driver features are taken into account when registering debugfs files. v3: - files[i].driver_features == 0 actually means "don't care" v2: - use drm_core_check_all_features() Cc: Ville Syrjälä Cc: Thomas Zimmermann Reviewed-by: Thomas Zimmermann Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20200123124801.14958-2-jani.nikula@intel.com