On Sun, Apr 5, 2020 at 2:41 PM Stefan Schaeckeler <schaecsn@xxxxxxx> wrote: > > Hello Wolfram, > > > > > This patch is based on Andy Lutomirski's iMC SMBus driver patch-set > > > > https://lkml.org/lkml/2016/4/28/926. It never made it into the kernel. I hope > > > > this rewrite will: > > > > > > > > > > > > Overview > > > > > > > > Modern Intel memory controllers host an SMBus controller and connection to > > > > DIMMs and their thermal sensors. The memory controller firmware has three modes > > > > of operation: Closed Loop Thermal Throttling (CLTT), Open Loop Thermal > > > > Throttling (OLTT) and none. > > > > > > > > - CLTT: The memory controller firmware is periodically accessing the DIMM > > > > temperature sensor over the SMBus. > > > > > > > > > > > > > I think this is great! One question, though: what happens if the > > > system is in CLTT mode but you disable CLTT and claim the bus for too > > > long? For example, if there's an infinite loop or other lockup which > > > you have the tsod polling interval set to 0? Does the system catch > > > fire or does the system do something intelligent like temporarily > > > switching to open loop? > > > > Any news on this question? > > Thank you for your interest in this patch. You can read my reply here > https://lkml.org/lkml/2020/3/1/216 I think it could make sense to upstream this driver but to require a scary boot-time option to enable it. Maybe i2c_imc.dangerous=1? > > Stefan
