User Guide

Errata
Specification Update 37
KBL052 Integrated Audio Codec May Not be Detected
Problem
Integrated Audio Codec may lose power when LPSP (Low-Power Single Pipe) mode is
enabled for an eDP* (embedded DisplayPort) or DP/HDMI ports. Platforms with
Intel® SST (Intel® Smart Sound Technology) enabled are not affected.
Implication
The Audio Bus driver may attempt to do enumeration of Codecs when eDP or
DP/HDMI port enters LPSP mode, due to this erratum, the Integrated Audio Codec
will not be detected and audio maybe be lost.
Workaround
Intel® Graphics Driver 15.40.11.4312 or later will prevent the Integrated Audio
Codec from losing power when LPSP mode is enabled.
Status For the steppings affected, see the Summary Table of Changes.
KBL053 Display Flickering May be Observed with Specific eDP Panels
Problem
The processor may incorrectly configure transmitter buffer characteristics if the
associated eDP panel requests VESA equalization preset 3, 5, 6, or 8.
Implication Display flickering or display loss maybe observed.
Workaround
Intel® Graphics Driver version 15.40.12.4326 or later contains a workaround for this
erratum.
Status For the steppings affected, see the Summary Table of Changes.
KBL054 Incorrect Branch Predicted Bit in BTS/BTM Branch Records
Problem
BTS (Branch Trace Store) and BTM (Branch Trace Message) send branch records to
the Debug Store management area and system bus respectively. The Branch
Predicted bit (bit 4 of eighth byte in BTS/BTM records) should report whether the
most recent branch was predicted correctly. Due to this erratum, the Branch
Predicted bit may be incorrect.
Implication BTS and BTM cannot be used to determine the accuracy of branch prediction.
Workaround None identified.
Status For the steppings affected, see the Summary Table of Changes.
KBL055
MACHINE_CLEARS.MEMORY_ORDERING Performance Monitoring Event May
Undercount
Problem
The performance monitoring event MACHINE_CLEARS.MEMORY_ORDERING (Event
C3H; Umask 02H) counts the number of machine clears caused by memory ordering
conflicts. However due to this erratum, this event may undercount for
VGATHER*/VPGATHER* instructions of four or more elements.
Implication
MACHINE_CLEARS.MEMORY_ORDERING performance monitoring event may
undercount.
Workaround None identified.
Status For the steppings affected, see the Summary Table of Changes.