The newest AMD Linux optimization patch for the kernel aims to introduce a cool down period for the AMD Platform Security Processor (PSP) after each I2C transaction between the x86 CPU and the PSP.
Jan Dabros of Semihalf, a Polish embedded systems engineering firm that has previously worked on Linux patches around AMD PSP, suggested this kernel patch on Monday as a means of optimizing performance.
This cool down timer for the AMD PSP Linux driver would limit the amount of transactions with the PSP during which the bus isn’t released after each I2C transaction. Currently the proposed cool down period is 100ms.
The proposed patch to the i2c-designware-amdpsp Linux driver can be found on the kernel mailing list where it’s currently awaiting review. No performance measurements around this AMD PSP driver change were shared as part of the patch.