With the default 6 icamerasrc buffers the camera HAL ran out of pending
requests and dropped every fourth sensor frame, capping output at ~22.5 fps.
Using 10 buffers keeps the request queue fed and restores 30 fps.
Adds hardware.ipu6 for the built-in MIPI camera, plus two overlay
fixes needed for it to actually work on this hardware:
- Pin icamerasrc-ipu6epmtl to the same release tag already used by
ipu6-camera-bins/ipu6-camera-hal (20250923_ov02e). The version
nixpkgs currently pulls is an Intel internal IoT/Panther-Lake
validation build whose device table only lists external USB
AR0234 test sensors, never the real ov08x40, so the camera never
gets selected.
- Patch ipu6-camera-hal's hardcoded IVSC/CVS entity name from
"Intel IVSC CSI" (the out-of-tree ivsc driver's name) to "Intel
CVS" (the mainlined intel_cvs driver's name). The mismatch broke
I2C bus address resolution for the sensor, which cascaded into
wrong stream configs and black/missing video.
Alexander Heldt