Re: kern/59253: amdzentemp fails to register with sysmon

["Paul Goyette via gnats" <gnats-admin%NetBSD.org@localhost>]

The following reply was made to PR kern/59253; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/59253: amdzentemp fails to register with sysmon
Date: Sun, 6 Apr 2025 20:22:41 -0700 (PDT)

 OK, I think we have identified the real culprint...
 
 When the amdsmn module is built-in, it gets to claim an attachment
 at ``pci 0 dev 0 function 0''.  But if the module isn't built-in,
 the driver for pchb claims that bus address for pchb0, and later
 on when the amdsmn module gets loaded, it cannot attach an instance
 because the attachment is already claimed.  We cannot have two
 devices at the same address.
 
 Not sure what to do here.  For now I will live with the built-in
 version of things.  Ideas on solving the problem "correctly" will
 br appreciated.
 
 Fo the record:
 
 With loadable (non-built-in) amdsmn we have
 
  	pchb0 at pci0 dev 0 function 0: vendor 1022 product 14d8 (rev. 0x00)
  	pchb1 at pci0 dev 1 function 0: vendor 1022 product 14da (rev. 0x00)
 
 With built-in amdsmn we have
 
  	amdsmn0 at pci0 dev 0 function 0: AMD System Management Network
  	pchb0 at pci0 dev 1 function 0: vendor 1022 product 14da (rev. 0x00)
 
 Sidebar: I'm guessing that the built-in amdsmn driver gets first
 chance at claiming the attachment is due to the alphabetic sorting of
 sources and objects within kernel Makefiles.  This can be confirmed
 by examining the kernel's generated ioconf.[ch] file.
 
 
 
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