SD and cameras

SD/SDHCI

drivers/sd/driver_sdhci.c - the host controller family; cards appear as block instances (sd0). Board-specific on real hardware.

Cameras (UVC + MJPEG)

drivers/camera/driver_camera.c + driver_camera_uvc.c (the USB Video Class) + lib_mjpeg.c (the decoder).

oc> uvc        (UVC device status)
oc> uvctest    (frame capture test)

Frames decode through the in-tree MJPEG decoder - ISO endpoints zero-pad tails (no OOB reads), and the capture path is usb_camera_test-gated.