PCI address of mapped OpenCL buffer object?


Is it possible to query the PCI bus address of an OpenCL buffer object mapped into host address space? I would like a frame grabber card to directly grab into GPU memory, which, according to its documentation, should be possible. The card’s API allows to specify the destination address either as a host address or a physical address, but the host address variant doesn’t work for reasons I don’t know and will investigate separately. In the meantime, I’m curious if it can write directly to a PCI address (i.e., to GPU memory). At least I succeeded in crashing the machine by providing a random physical address to the frame grabber, which confirms that it is able to access off-board memory :slight_smile:

my system:
*) OS: Windows 7 Professional
*) GPU: AMD Radeon HD7950 (driver 8.951.0.0, AMD ADD SDK 2.6.831.4)
*) frame grabber: Matrox Solios eV-CL (driver 9.10.723.0, MIL-Lite 9.00 R2)

I’m glad about any hints!

Thanks & kind regards,