Issue #121 has been updated by Anastasios Koutian.
Patrick Rudolph wrote in #note-75:
I compared the vendor ACPI code for T520 and T530:
- The T520 is missing _CST entries, thus the C-states are reported in FADT. I couldn't find a firmware dump that has a FADT.
- The T530 has _CST, but the latencies are higher: For C3 148usec, vs 63 in coreboot. It's possible that too short advertised exit latencies causes issues when meeting deadlines within the kernel. The kernel will pick deeper C-states, while it shouldn't, as it assumes that those wake much faster.
Hi Patrick,
I have done some digging with MSRs but never looked into this particular one. I have a spare T420 motherboard now and I could flash the vendor firmware back in, to examine the value. If that would contribute to solving this issue, I'd be happy to do it. Thank you for looking into this.
---------------------------------------- Bug #121: T520: Hangs in OS https://ticket.coreboot.org/issues/121#change-1667
* Author: Julz Buckton * Status: New * Priority: Normal * Start date: 2017-06-09 ---------------------------------------- I have been running coreboot since 2017.04.15 and have experienced hangs ever since then. It was suggested by folk on the IRC that I run memtest to check for incorrect raminit causing errors, however I have run memtest for 12 hours straight with no errors.
Due to the ambiguous nature of the hangs (immediate freeze with no warning signs, audio gets stuck repeating the last 50ms or so of noise, not sure what this effect is called) I don't have much useful information other than the .config and dmesg. However one thing I can say with high confidence is that the hangs occur significantly more frequently in Linux (*buntu distros) than Windows 10. Within an hour of launching Linux a hang is likely, whereas Windows typically runs for many hours before a hang occurs. I considered this an insignificant anecdotal anomaly at first but over the course of the nearly 2 months I have been running coreboot it seems to be a solid trend. The hangs occur anywhere, typically during mere desktop usage or basic web browsing.
Additionally there is another form of hang I experience where the screen goes black except for some sort of graphical corruption down the left side (http://i.imgur.com/4zWrlpX.jpg), whether this is related to the more common total freeze hangs I don't know but I figured I should include it nonetheless. These hangs only occur about 1:20 compared to the regular hangs.
---Files-------------------------------- config (20.7 KB) dmesg.txt (57.3 KB) cbmem-raminit.txt (62 KB) lspci.txt (29.6 KB) cpuinfo.txt (3.94 KB) defconfig (1023 Bytes) defconfig (699 Bytes)