Re: port-amd64/42980: satalink DMA fails under amd64

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

The following reply was made to PR port-amd64/42980; it has been noted by GNATS.

From: Manuel Bouyer <bouyer%antioche.eu.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: port-amd64-maintainer%NetBSD.org@localhost, 
gnats-admin%NetBSD.org@localhost,
        netbsd-bugs%NetBSD.org@localhost
Subject: Re: port-amd64/42980: satalink DMA fails under amd64
Date: Tue, 16 Mar 2010 21:36:01 +0100

 On Mon, Mar 15, 2010 at 11:35:01PM +0000, julian.bourne%gmail.com@localhost 
wrote:
 > >Number:         42980
 > >Category:       port-amd64
 > >Synopsis:       satalink DMA fails under amd64
 > >Confidential:   no
 > >Severity:       serious
 > >Priority:       medium
 > >Responsible:    port-amd64-maintainer
 > >State:          open
 > >Class:          sw-bug
 > >Submitter-Id:   net
 > >Arrival-Date:   Mon Mar 15 23:35:00 +0000 2010
 > >Originator:     Julian Bourne
 > >Release:        5.0.2
 > >Organization:
 > >Environment:
 > NetBSD 5.0.2 (XEN3_DOM0) #0
 > >Description:
 > The satalink driver doesn't support DMA under NetBSD 5.0.2 amd64.  It works 
 > properly on exactly the same hardware under NetBSD 5.0.2 i386.
 > 
 > satalink0 at pci1 dev 9 function 0
 > satalink0: Silicon Image SATALink 3512 (rev. 0x01)
 > satalink0: SATALink BA5 register space disabled
 > satalink0: bus-master DMA support present
 > satalink0: primary channel wired to native-PCI mode
 > satalink0: using ioapic0 pin 17, event channel 10 for native-PCI interrupt
 > atabus1 at satalink0 channel 0
 > satalink0: secondary channel wired to native-PCI mode
 > atabus2 at satalink0 channel 1
 > satalink0: port 0: device present, speed: 1.5Gb/s
 > satalink0: port 1: device present, speed: 1.5Gb/s
 > satalink0:0: unable to create xfer table DMA map for drive 0, error=22
 > wd0(satalink0:0:0): using PIO mode 4
 > satalink0:1: unable to create xfer table DMA map for drive 0, error=22
 > wd1(satalink0:1:0): using PIO mode 4
 > 
 > 
 > 
 > >How-To-Repeat:
 > Use an amd64 system equipped with a PCI bus and a SataLink 3512 card.  Boot 
 > with NetBSD 5.0.2 amd64 (xen or native); it fails with the message 
 > described, and falls back to PIO mode 4 giving about 3MB/s for attached 
 > devices.
 > 
 > Boot with NetBSD 5.0.2 i386 (native); it succeeds for DMA and gives about 
 > 100MB/s for attached devices (in this case a pair of WD7500AALS drives).
 > >Fix:
 > Not sure exactly how to solve the problem, but I did look at the satalink 
 > code and it seems like it *might* be failing because it requests 32bit 
 > memory, rather than 64bit memory for DMA.
 
 It's expected that the driver requests 32bit memory for DMA if the card
 doesn't support 64bits. 22 is EINVAL, could you see which bus_dma call
 fails, and what arguments were passed to it ? it looks like a
 bus_dma(9) function is called with wrong arguments.
 
 -- 
 Manuel Bouyer <bouyer%antioche.eu.org@localhost>
      NetBSD: 26 ans d'experience feront toujours la difference
 --