Re: kern/56244: Expresscard re(4) does not attach

[mlelstv%serpens.de@localhost (Michael van Elst)]

The following reply was made to PR kern/56244; it has been noted by GNATS.

From: mlelstv%serpens.de@localhost (Michael van Elst)
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/56244: Expresscard re(4) does not attach
Date: Thu, 10 Jun 2021 20:09:06 -0000 (UTC)

 rherdware%yahoo.com@localhost writes:
 
 >I got a gigabit ethernet ExpressCard/34 for a Thinkpad R400 that I wanted to put to some actual use. However when booted with the card inserted it does not attach. It does, of course, work with Windows 10.
 
 >In the log this single line appears:
 >re0 at pci3 dev 0 function 0autoconfiguration error:  : can't map registers
 
 The kernel configures PCI only with the kernel option PCI_NETBSD_CONFIGURE,
 otherwise it relies on firmware (BIOS/UEFI) to do the configuration.
 
 The kernel also doesn't support PCI hotplug. It scans PCI busses
 once and allocates address space for all devices found.
 
 ExpressCard needs both.
 
 I have some local patches that handle ExpressCards on my T420 when
 plugged in at boot time, but without hotplug support, it isn't
 worth much. Especially when you have an USB3.0 ExpressCard that
 gets ejected when you plug in the USB cable thanks to the lousy
 mechanical qualities of the ExpressCard specification.