Hello, I am in the process of porting a known working linux driver for a pci device from an x86 machine to a mips machine. This is my first time developing a driver under mips (but not the first time with x86) so I am learning some of the differences and gotchas that exist when porting a driver like this. My most recent problem exists when setting up dma between the host and the device. I am using the following two websites as guides for doing this: https://lwn.net/Articles/28230/ https://lwn.net/Articles/28092/ In addition I am using LDD. To create the dma memory area I am using the function "pci_alloc_consistent". When I pass the "dma_handle" (as I understand it the host's physical address of the dma memory), to the pci device, the device in the x86 box correctly access this memory, not so in the mips box. Not sure if this is helpful, but the fuction returns the following addresses on the mips when I use it: dma_handle=0x026f0000 size=0x00010000 cpu_addr=0xa26f0000 Does this physical address seem abnormally low? It is well outside the range of the PCI BARs which exist around 0x20000000. Anything I should know about using pci_alloc_consistent on a mips? If you need more information to understand the situation I'd be happy to supply it but right now I'm not sure what to supply. Thanks, Jon
