Re: port-sparc64/54211: esiop stopped detecting boot disk

["Michael L. Hitch" <mhitch%montana.edu@localhost>]

The following reply was made to PR port-sparc64/54211; it has been noted by GNATS.

From: "Michael L. Hitch" <mhitch%montana.edu@localhost>
To: "Michael L. Hitch" <mhitch%NetBSD.org@localhost>
Cc: gnats-bugs%netbsd.org@localhost, port-sparc64-maintainer%netbsd.org@localhost, 
    gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost
Subject: Re: port-sparc64/54211: esiop stopped detecting boot disk
Date: Tue, 3 Dec 2019 11:32:08 -0700 (MST)

 On Thu, 14 Nov 2019, Michael L. Hitch wrote:
 
 >  I noticed that sparc64 switched from gcc6 to gcc7 back in Februrary, so my 
 > first wild guess is something in gcc7 may be causing the problem. There were 
 > no noticable changes in the mpt code between NetBSD-8 and NetBSD-9, so I 
 > don't know if the problem is in the mpt code, or something else it uses.
 >
 >  I will probably try this again with an older tree that still has gcc6 and I 
 > can try with both versions).  I was doing that a year ago when I was having 
 > trouble with the Ultra 45 crashing while configuring the audio driver.
 
    I had time over the Thanksgiving weekend to track this down.  I did 
 determine that the switch to gcc7 did not cause this, and the commit that 
 did was a few weeks later.  The culprit is revision 1.69 of sys/i2c/i2c.c 
 (certainly not very obvious).
 
    That change resulted in the device probe trying to configure a 
 non-existant i2c device on the Ultra 45.  Inspecting the dmesg output in 
 this ticket shows the same thing.  A working kernel shows:
 
 [   1.0000000] gpio at iic0 addr 0x18 not configured
 
    While a failing kernel shows:
 
 [   1.0000000] admtemp0 at iic0 addr 0x18:  temperature sensor: id. 0xf0, 
 rev. 0xf0
 
    Reverting this change results in a working kernel. both for -current and 
 netbsd-9.
 
 Mike
 
 
 ---
 Michael L. Hitch                        mhitch%montana.edu@localhost
 Operations Consulting,  University Information Technology
 Montana State University, Bozeman, MT     USA