[PATCH] drm/vkms: Add "hardware limitation" emulation TODO

From: Louis Chauvet
Date: Tue Feb 25 2025 - 10:46:42 EST


Add the hardware limitation todo.

Signed-off-by: Louis Chauvet <louis.chauvet@xxxxxxxxxxx>
---
Documentation/gpu/vkms.rst | 9 +++++++++
1 file changed, 9 insertions(+)

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.

---
base-commit: acf3256160bdabcb5c07032f3bf6eb5a21f5b95f
change-id: 20250225-vkms-update-todo-50701246bcd8

Best regards,
--
Louis Chauvet <louis.chauvet@xxxxxxxxxxx>