Re: kern/55540 (aceride Fails To Downgrade Transfer Mode)

[Jaromir Dolecek <jaromir.dolecek%gmail.com@localhost>]

I will look into this once I am back from vacations on Aug 16th

> Le 9 août 2020 à 07:45, Martin Husemann <martin%duskware.de@localhost> a écrit :
> 
> The following reply was made to PR kern/55540; it has been noted by GNATS.
> 
> From: Martin Husemann <martin%duskware.de@localhost>
> To: Kyra Sable <kyra.sable%mail.ru@localhost>
> Cc: gnats-bugs%netbsd.org@localhost
> Subject: Re: kern/55540 (aceride Fails To Downgrade Transfer Mode)
> Date: Sun, 9 Aug 2020 07:43:02 +0200
> 
>> On Sat, Aug 08, 2020 at 11:20:14PM -0400, Kyra Sable wrote:
>> Scarcely "not relevant any more" given NetBSD's intended target audience.
> 
> Thanks for hunting this done, but I think you misunderstood the commit log
> message. We certainly still care for this devices still.
> 
> I have never seen this exact version of the error / downgrade path, and
> I am typing this on a machine that has one:
> 
> aceride0 at pci3 dev 13 function 0: Acer Labs M5229 UDMA IDE Controller (rev. 0xc4)
> aceride0: bus-master DMA support present
> aceride0: using PIO transfers above 137GB as workaround for 48bit DMA access bug, expect reduced performance
> aceride0: primary channel configured to native-PCI mode
> aceride0: using ivec 1f98 for native-PCI interrupt
> [..]
> cd0 at atapibus0 drive 0: <JLMS XJ-HD166S, , D3S4> cdrom removable
> cd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 2 (Ultra/33)
> cd0(aceride0:1:0): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) (using DMA)
> 
> and the cd works fine.
> 
> BUT: I have a ATA<->SD card converter on that ATA bus that I use to boot the
> machine (all "disks" on SATA that firmware does not know about), and I have
> to disable UDMA on that, otherwise it will not be able write to the "disk".
> 
> (but then failure mode looks quite different to what you reported).
> 
> I always assumed this is a bug in the firmware of the SD card converter.
> 
> I will put another (real) ATA disk in this machine and test, and also check
> if I have more machines with aceride.
> 
> This might be a driver bug, or a quirk in combination with certain ATA disks
> and aceride. We need to dig deeper and avoid the original HBA error, or
> recognize the issue and adjust capabilities, so we end up with a working
> setup w/o the error -> degration path.
> 
> Martin
> 
> P.S.: Jaromir - could this be similar to the cmdide issue we fixed recently?
>