On Tue, May 16, 2017 at 10:52:05AM +0530, Oza Pawandeep wrote: > current device framework and OF framework integration assumes s/current/The current/ > dma-ranges in a way where memory-mapped devices define their > dma-ranges. (child-bus-address, parent-bus-address, length). > > of_dma_configure is specifically written to take care of memory > mapped devices. but no implementation exists for pci to take > care of pcie based memory ranges. s/pci/PCI/ (also other occurrences below) s/pcie/PCIe/ I don't see how PCIe is relevant here. The bridge might support PCIe, but I don't think anything here is actually specific to PCIe. If that's the case, I think it's confusing to mention PCIe. > for e.g. iproc based SOCs and other SOCs(suc as rcar) have PCI > world dma-ranges. > dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; > > this patch serves following: > > 1) exposes interface to the pci host driver for their > inbound memory ranges > > 2) provide an interface to callers such as of_dma_get_ranges. > so then the returned size get best possible (largest) dma_mask. > because PCI RC drivers do not call APIs such as > dma_set_coherent_mask() and hence rather it shows its addressing > capabilities based on dma-ranges. > for e.g. > dma-ranges = <0x43000000 0x00 0x00 0x00 0x00 0x80 0x00>; > we should get dev->coherent_dma_mask=0x7fffffffff. > > 3) this patch handles multiple inbound windows and dma-ranges. > it is left to the caller, how it wants to use them. > the new function returns the resources in a standard and unform way > > 4) this way the callers of for e.g. of_dma_get_ranges > does not need to change. Please start sentences with a capital letter.