> 2. Use the GPUVM inside the GPU to access system memory. The > limitation here is that the GPUVM uses 40-bit addresses, so the > virtual address range must be in the lower 40-bit address range of the > CPU. Access speed is limited by PCI-e bandwidth. Another limitation is > that the system memory pages must be pinned as the GPU doesn't support > page faults. > > The operation of reserving address space and BO creation is one IOCTL, > while the mapping of the BO to the address space is a second IOCTL. > There are of course unmap and free IOCTLs. The separation is done for > a couple of reasons: > > 1. If the application knows that it wants to use only part of the > memory area it allocated, then there is no point in pinning all the > BOs. So, the application can map/unmap just part of the allocation. > > 2. If the application knows that it has finished using the BOs, and it > also knows that it will use them later on, it can unmap the BOs (to > make them unpinned) but not free them so the memory is still reserved > (with its contents intact). Yes, thanks Oled. I think this is pretty much exactly how I imagine things to work. I'll post my code soon and see what you guys think. There was some misunderstanding on my part on how bo's work, so I need to rework some stuff. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
