From: Thierry Reding treding@nvidia.com
This small series addresses a minor issue with how IOMMU support is wired up on various Tegra generations. Currently the virtual "card" device is used to allocate DMA memory for, but since that device does not actually exist, the path to memory cannot be correctly described.
To address this, this series moves to using the ADMAIF as the DMA device for audio. This is a real device that can have a proper DMA mask set and with which a stream ID can be associated with in the SMMU. The memory accesses technically originate from the ADMA controller (that the ADMAIF uses), but DMA channel are dynamically allocated at runtime while DMA memory is allocated at driver load time, drivers won't have access to the ADMA device yet.
Further patches will be required to correct this issue on Tegra186 and Tegra210, but I wanted to get feedback on this approach first.
Thierry
Thierry Reding (2): ASoC: tegra: Use ADMAIF component for DMA allocations arm64: tegra: Enable audio IOMMU support on Tegra194
arch/arm64/boot/dts/nvidia/tegra194.dtsi | 4 ++++ sound/soc/tegra/tegra_pcm.c | 21 +++++++++------------ 2 files changed, 13 insertions(+), 12 deletions(-)