CVS commit: src/sys/arch/x86/x86

["matthew green" <mrg%netbsd.org@localhost>]

Module Name:    src
Committed By:   mrg
Date:           Fri Oct 27 05:45:00 UTC 2023

Modified Files:
        src/sys/arch/x86/x86: errata.c

Log Message:
x86: handle AMD errata 1474: A CPU core may hang after about 1044 days

from the new comment:

 * This requires disabling CC6 power level, which can be a performance
 * issue since it stops full turbo in some implementations (eg, half the
 * cores must be in CC6 to achieve the highest boost level.)  Set a timer
 * to fire in 1000 days -- except NetBSD timers end up having a signed
 * 32-bit hz-based value, which rolls over in under 25 days with HZ=1000,
 * and doing xcall(9) or kthread(9) from a callout is not allowed anyway,
 * so just have a kthread wait 1 day for 1000 times.

documented in:

 https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/revision-guides/56323-PUB_1_01.pdf


To generate a diff of this commit:
cvs rdiff -u -r1.34 -r1.35 src/sys/arch/x86/x86/errata.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.