Can Nvidia Orin NX works with host1x without iommu for deepstream?

[jpruiz84]

Hi

I would like to know if I can configure the host1x to work without iommu for deepstream applications in Nvidia Orin NX. I am working with JP 6.1, and I have created this device tree to disable the iommu:

/dts-v1/;

#include "tegra234-p3768-0000+p3767-0000.dts"
#include "tegra234-p3768-0000+p3767-xxxx-nv-common.dtsi"

/{

	bus@0 {

		host1x@13e00000 {
            /delete-property/ iommus;
        };
    };
};

Display and GPU worked OK with this configuration. Nevertheless, when I am running a deepstream application I got always a cdma_timeout_handler error:

tegra-host1x 13e00000.host1x: cdma_timeout_handler: timeout: 51 (51-multiqueue0:src), HW thresh 0, done 2

I attach the full logs:

nvidia-bug-report-jetson.log (702.9 KB)

Thanks

@JonHunter

[DaneLLL]

Hi,
We don’t support this on default L4T release. May we know why you disable it? Would like to get more information.

[jpruiz84]

We are working in a research project in which we have created a virtual machine over KVM to isolate display, GPU, and machine learning devices. We were able to virtualize the BPMP services in order to passtrough successfully host1x, DCE, the nvdisplay and the GPU to this VM.

We have success with all mentioned devices but VIC. Everytime that deepstream wants to use the VIC we have a cdma timeout error. We were able to replicate this error in the host by disabeling IOMMU in host1x. We have debuged the drivers source code and we think that the VIC only accept cdma channels that allocated over an IOMMU.

For this reason we want to know if you have any use case or configiration that we can use to setup our decices without the IOMMU.

Thanks

[jpruiz84]

Hi

Is there some update about this? We would like to know in which use cases host1x without iommu is supported. I now that nvidia,tegra210-host1x works without IOMMU. Is there a way to configure nvidia,tegra234-host1x to work without IOMMU?

[DaneLLL]

Hi,
This is not default mode in L4T releases. We would suggest not to disable IOMMU while running the use-cases.