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a=openpgp; fpr=8B7104AE9A272D6693F527F2EC1883F55E0B40A5 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdekvddutdcutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephfffufggtgfgkffvvefosehtjeertdertdejnecuhfhrohhmpefnohhuihhsucevhhgruhhvvghtuceolhhouhhishdrtghhrghuvhgvthessghoohhtlhhinhdrtghomheqnecuggftrfgrthhtvghrnhepueetjeeggeffvdegkeetudekjeevkeehheduledtgeejhfduvdeuleehleffgefgnecukfhppeeltddrkeelrdduieefrdduvdejnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepledtrdekledrudeifedruddvjedphhgvlhhopegludejvddrudekrddtrddungdpmhgrihhlfhhrohhmpehlohhuihhsrdgthhgruhhvvghtsegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopedufedprhgtphhtthhopehmrhhiphgrrhgusehkvghrnhgvlhdrohhrghdprhgtphhtthhopegrihhrlhhivggusehgmhgrihhlrdgtohhmpdhrtghpthhtohephhgrmhhohhgrmhhmvggurdhsrgesghhmrghilhdrtghomhdprhgtphhtthhopegtohhrsggvtheslhifnhdrnhgvthdprhgtphhtthhopehlihhnuhigqdguohgtsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhouhhis hdrtghhrghuvhgvthessghoohhtlhhinhdrtghomhdprhgtphhtthhopegurhhiqdguvghvvghlsehlihhsthhsrdhfrhgvvgguvghskhhtohhprdhorhhgpdhrtghpthhtohepshhimhhonhgrsehffhiflhhlrdgthh X-GND-Sasl: louis.chauvet@bootlin.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Add the hardware limitation todo. Signed-off-by: Louis Chauvet --- Documentation/gpu/vkms.rst | 9 +++++++++ 1 file changed, 9 insertions(+) --- base-commit: acf3256160bdabcb5c07032f3bf6eb5a21f5b95f change-id: 20250225-vkms-update-todo-50701246bcd8 Best regards, diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst index ba04ac7c2167..d5bc602547e7 100644 --- a/Documentation/gpu/vkms.rst +++ b/Documentation/gpu/vkms.rst @@ -147,6 +147,15 @@ module. Use/Test-cases: - Change output configuration: Plug/unplug screens, change EDID, allow changing the refresh rate. +- Emulating Hardware Limitations with eBPF for MST and Atomic Checks + Hardware limitations can often prevent valid DRM configurations during + atomic checks. Examples of such limitations include bandwidth constraints in + MST and limited clock signals for multiple CRTCs. + These limitations are dynamic and require extensive checks, making them + difficult to describe statically. To address this, we propose creating an + eBPF interface for atomic checks. This interface will allow userspace applications + to simulate and enforce custom hardware limitations. + The currently proposed solution is to expose vkms configuration through configfs. All existing module options should be supported through configfs too.