On Mon, Jul 10, 2023 at 11:22:52AM +0300, Stanimir Varbanov wrote: > Add def_domain_type implementation op and override default IOMMU > domain Kconfig option (CONFIG_IOMMU_DEFAULT_PASSTHROUGH=y), which > could be enabled on some distros. The current quirk has been done > for Tegra234 machine, because I found the issue on it. The issue > itself appears on USB host controller which cannot be initialized > without IOMMU translation. Something more, we proved that IOMMU > translation is needed for display and GPU drivers as well. Generically, if you find HW combinations where certain end points cannot work with passthrough (which is really weird in the first place) it should be narrowly quirked - not just an entire platform. Also we don't really have a way to force non-passthrough, ARM32 systems will always run in passthrough, for instance. Broadly the kernel expects it to work. Jason
