>-----Original Message----- >From: Intel-wired-lan [mailto:[email protected]] On >Behalf Of Shannon Nelson >Sent: Thursday, February 01, 2018 3:46 PM >To: Tantilov, Emil S <[email protected]> >Cc: [email protected]; [email protected] >Subject: [Intel-wired-lan] Possible read-modify-write bug in ixgbe x550 >phy setup > >Hi Emil, > >I was looking through a set of ixgbe patches and came across this commit > > commit 410a494902777c11f95031d9ed757d7f8f09c5c6 > ixgbe: add write flush when configuring CS4223/7 > >and am wondering about the setting of reg_phy_ext in the middle of >ixgbe_setup_mac_link_sfp_x550a(). It looks like it is read from the >PHY, modified to remove the CX1 and SR mode bits, but then those bits >are overwritten in the "if (setup_linear)" block immediately following, >and that is what gets written back out.
Hi Shannon, This is pretty standard clear before set, so you're right that it would make more sense to have |= rather than =. Are you seeing an issue, or did you catch this via code inspection? Thanks, Emil
