On Mon, 15 Feb 2021, Maciej W. Rozycki wrote:

 I hope to have the adapter properly fixed soon and I'll look at the Malta 
side now, possibly using the old server whose DEFPA has worked flawlessly 
for some 20 years now.  I have planned to use the interface to supply NFS 
root, which I think should be enough of a stress test.

 Card reworked now and network wired, so using the new server actually.  
I haven't booted Linux on my Malta for a while now, but it turns out to 
work just fine, and your patch set does not regress it booting multi-user 
NFS-rooted over FDDI.

 I note however that the system does not reboot properly:

sd 0:0:0:0: [sda] Synchronizing SCSI cache
reboot: Restarting system
Reboot failed -- System halted

which is a regression, and also the MMIO-mapped discrete CBUS UART (ttyS2) 
does not sign in anymore either:

Serial: 8250/16550 driver, 5 ports, IRQ sharing enabled
printk: console [ttyS0] disabled
serial8250.0: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
printk: console [ttyS0] enabled
printk: console [ttyS0] enabled
printk: bootconsole [uart8250] disabled
printk: bootconsole [uart8250] disabled
serial8250.0: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A

while long ago:

Serial driver version 5.05c (2001-07-08) with MANY_PORTS SHARE_IRQ SERIAL_PCI enabled
ttyS28 at 0x03f8 (irq = 4) is a 16550A
ttyS29 at 0x02f8 (irq = 3) is a 16550A
ttyS30 at 0x0000 (irq = 20) is a 16550

(I don't know why the line numbers reported were so odd back then, but the 
standard character device major:minor numbers for ttyS0-2 just worked), so 
there's probably something wrong with platform device registration.  ISTR 
using the CBUS UART as a console device at one point too.

  Maciej