The purpose of the matrix is mostly to showcase what Qualcomm has enabled in the publicly released firmware, and that does include IPIP6. The tricky part is getting everything properly wired up. Qualcomm provides the source for nss-drv, nss-clients, nss-ecm, and a few kernel patches, and I’ve mostly managed to retrofit those to work with newer kernels—but it’s best-effort. Some features like IPIP6 are hard to confirm since my ISP already provides native dual-stack, so I can’t reliably replicate or troubleshoot where offloading might be failing. If your image was built with dynamic debug support, you can try enabling targeted logging for IPIP6:
# NSS Client
echo 'file *tunipip* +p' > /sys/kernel/debug/dynamic_debug/control
# ECM
echo 'func *ecm*tunipip* +p' > /sys/kernel/debug/dynamic_debug/control
# In a separate terminal you should monitor syslog before reloading
logread -f
# Reload connection and ECM
service network restart
service qca-nss-ecm restart
NSS SQM offloading works at the port level (wan, lan1, lan2, lan#). So long as your shaped interface is wan it should work.
This is on a pppoe connection correct? The formula in the example is also for ftth, but biased towards non-pppoe. So you also have to account for the 44 bytes overhead. Could you post /etc/config/sqm?
Funny story, the offloading that Qualcomm provides for mesh is specific to 802.11s spec. It was introduced in NSS firmware 11.4 (likely as a technical preview) but dropped soon after. Their own proprietary driver qca-wifi (which all OEMs stick to) never used it. They instead use EasyMesh, which is essentially just Multi-AP AP+STA backhaul. They just re-use the same offloading hooks for AP/STA/WDS.