Hi, On Wed, Jan 16, 2019 at 8:30 PM Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> wrote: > > For devices attached to an IOMMU, translation between IOVA and physical > addresses is no longer 1:1 and dma-ranges should be specified to > describe the available IOVA address space. > > On SDM845 the busses are implemented with 36 address bits, so dma-ranges > must be defined to reduce the size of the IOVA address space from the 48 > bits supported by the SMMU. Without this DMA allocations may end up with > IOVAs outside the valid range, that gets truncated by the bus between > the device and its translation unit. > > Also extend ranges to describe the available address space. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> > --- > > Changes since v3: > - Split this out from patch 1. > - Rewrote commit message from scratch > > arch/arm64/boot/dts/qcom/sdm845.dtsi | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Tested-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
