i386/105616: UART PCI device just silent...

[Marcel Moolenaar]

The following reply was made to PR i386/105616; it has been noted by GNATS.

From: Marcel Moolenaar <xcllnt at mac.com>
To: Helge Oldach <puc-uart at oldach.net>
Cc: FreeBSD-gnats-submit at FreeBSD.org
Subject: Re: i386/105616: UART PCI device just silent...
Date: Sun, 26 Nov 2006 23:21:50 -0800

 On Nov 26, 2006, at 11:11 PM, Helge Oldach wrote:
 
 > There are no specific hints for the puc-based UARTs. I understand that
 > PCI devices don't need such hints. Actually, both the "sio kernel" and
 > the "uart kernel" locate the device identically on the same IRQ and IO
 > ports.
 >
 > Am I mistaken here?
 
 No, not at all. You got it right.
 
 >> Why do you have PUC_FASTINTR for sio, but not for uart?
 >
 > I had just been trying to play with the knobs that I have in the  
 > config
 > file. PUC_FASTINTR reduces overruns somewhat for the "sio kernel"  
 > but it
 > doesn't change behaviour at all. Specifically, no impact on this  
 > issue.
 
 I think it's time to go back to the question why uart(4) detects
 the SUN 1889 chipset as 166550 compatible and not as 16650
 compatible. I think there may be a chipset-specific issue here
 that uart(4) seems to trigger. I need to get one of those cards
 and analyze the problem in more detail.
 
 In other words, I think we have gone over the differences and the
 only difference that remains is that sio(4) and uart(4) interact
 differently with the hardware.
 
 -- 
 Marcel Moolenaar
 xcllnt at mac.com