Hello, according to the respective Technical Reference Manual, the Arm Cortex-A78AE CPU cores that the Jetson Orin Nano Developer Kit is based on support the Statistical Profiling Extension (SPE). After upgrading the firmware with JetPack 6.0, I have installed stock Ubuntu 24.04 with kernel 6.8.0-41-generic, but the system doesn’t report SPE as being supported (e.g. no relevant entry in /sys/bus/event_source/devices). FYI the arm_spe_pmu kernel module is loaded and I have passed kpti=off on the kernel command line as required, which points to a firmware issue. Are there any plans to enable SPE support on the Jetson Orin Nano Developer Kit?
This is not we supported, suggest to use the version from JetPack for more testing.
Thank you for the suggestion. I tried with JetPack and kernel 5.15.136 (I had to compile the arm_spe_pmu kernel module separately because it is not part of the regular SD card image) - the result was the same.
Hi,
We don’t have much experience in the function. Would need other users to provide suggestion.
For capability of CPU cores, please check section 2.2 in module data sheet:
Hello, the statements in the data sheet are consistent with the information from the Technical Reference Manual (TRM). For instance, it says that a Performance Monitor Unit (PMU) based on the PMUv3 architecture is supported. PMUv3 is a technology that is in a very similar area as SPE, and both are quite useful for profiling the CPU-bound portions of a workload. However, the data sheet is not clear about the state of SPE support; the only relevant information that I have found is:
Cortex-A78AE CPU supports:
- Full implementation of Armv8.2-A architecture instruction set and select instructions from Armv8.3-A, Armv8.4-A, and Armv8.5-A extensions.
(SPE has been introduced by the Armv8.2-A architecture extension)
This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.