Re: [PATCH v3 00/10] Make the 32-bit ARM DMA API work with normal IOMMU DMA default domains (+ Tegra PoC)

From: Christoph Hellwig

Date: Thu Oct 29 2026 - 08:04:05 EST


On Mon, Oct 26, 2026 at 06:19:25PM +0900, Mikko Perttunen wrote:
> Robin suggested [1] that instead of teaching the legacy path about
> groups, we should explore modernizing the 32-bit ARM DMA code a bit by
> making it use domain cookies and have the core code own the domains, as
> is the case on other architectures. Still, ARM's own DMA code is kept to
> support existing drivers and APIs that expect it, and because dma-iommu
> is considered too big and unnecessary for 32-bit ARM.

Now that the different domain handling is gone, what speaks against
just using the generic dma-iommu code for arm32?