Does the honeycomb have iommu turned on from bios by default??
I heard it as to be enabled from. Bios but not sure how!!.
u-boot enables the SMMU but sets it as passthrough by default. The Linux driver then re-initializes the SMMU and if does not have iommu.passthrough=1 set on the kernel commandline will reconfigure it, then each driver is responsible for registering the memory ranges it needs access to.
OK, thanks alot just want to know before I embark on my project!!.
If you check dmesg you should see the SMMUv2 enabled and devices registered to it.
OK, can’t do it now, but will do!.
Thanks again!.