Tests conducted on an Exynos 2200 reference device (Android 13, kernel 5.10).
| Metric | MSS v2 (legacy) | MSS v3 | Improvement | |--------|----------------|--------|-------------| | IPC latency (P99) | 340 µs | 112 µs | -67% | | Throughput (data channel) | 1.2 Gbps | 3.8 Gbps | +216% | | Power (idle + connected) | 185 mW | 97 mW | -47% | | Modem firmware load time | 890 ms | 410 ms | -54% |
Benchmark conditions: 5G NR FR1 (n78), 100 MHz BW, TCP iperf3.
E IPC_RTR : mss_ver3_recv_data: invalid header
E MSS_V3 : tx timeout on channel 7
Analysis: Use samsung-ipc-log from LineageOS’s tools: samsung android modem device driver -mss ver.3-
adb shell "echo 0xFFFF > /sys/kernel/debug/sipc5/debug_mask"
adb shell cat /sys/kernel/debug/sipc5/stats
Possible causes:
Fixes:
Possible cause: MSS Ver.3 driver failed to load modem firmware. Tests conducted on an Exynos 2200 reference device
Check:
ls -l /dev/umts_*
dmesg | grep -i mss
Look for:
mss_v3: failed to boot modem
mss_v3: ipc rx timeout
Solution: Reflash modem binary (modem.bin or cm.bin) via Odin/Heimdall. Analysis : Use samsung-ipc-log from LineageOS’s tools: adb
If the modem is stuck but not dead:
echo 1 > /sys/devices/platform/modem/force_dump
This forces the driver to capture CP ramdump, saved to /data/log/ramdump_modem_*.
The samsung android modem device driver -mss ver.3- consists of several kernel modules and userspace helpers: