I just tested the latest releng build of the 4.0-Beta2 kernel, to see
if it would trigger the problem on my machine.  It worked fine for me,
I successfully transferred a 370MB file both ways.

(I see the only difference between our pcictl output was this:

@@ -15,7 +15,6 @@
       Address/data stepping: off
       System error (SERR): off
       Fast back-to-back transactions: off
-      Interrupt disable: off
     Status register: 0x84a0
       Capability List support: off
       66 MHz capable: on

Mine shows that "interrupt disable" entry.)

Dave

PS I don't imagine the dmesg from my machine is any more useful under
4.0-Beta2 than what I already posted, but just in case it's below.

NetBSD 4.0_BETA2 (GENERIC) #0: Fri Apr 13 21:06:39 PDT 2007
        
builds@wb25:/home/builds/ab/netbsd-4/macppc/200704130002Z-obj/home/builds/ab/netbsd-4/src/sys/arch/macppc/compile/GENERIC
total memory = 320 MB
avail memory = 300 MB
timecounter: Timecounters tick every 10.000 msec
init_interrupt: found OpenPIC @ pa 0x80040000, 0x80040000
mainbus0 (root)
cpu0 at mainbus0: 750 (Revision 3.0), ID 0 (primary)
cpu0: HID0 8090c0a4<EMCP,DOZE,DPM,ICE,DCE,SGE,BTIC,BHT>, powersave: 1
cpu0: 366.67 MHz, no-parity 512KB WB L2 cache (PB SRAM) at 2.5:1 ratio
uni_n0 at mainbus0 address 0xf8000000
ki2c0 at uni_n0 address 0xf8001000
iic0 at ki2c0: I2C bus
uninorth0 at mainbus0
pci0 at uninorth0 bus 0
pci0: i/o space, memory space enabled
pchb0 at pci0 dev 11 function 0
pchb0: Apple Computer UniNorth AGP Interface (rev. 0x00)
ofb0 at pci0 dev 16 function 0: ATI Technologies Rage L Mobility
ofb0: 800 x 600, 8bpp
wsdisplay0 at ofb0 kbdmux 1: console (std, vt100 emulation)
wsmux1: connecting to wsdisplay0
uninorth1 at mainbus0
pci1 at uninorth1 bus 0
pci1: i/o space, memory space enabled
pchb1 at pci1 dev 11 function 0
pchb1: Apple Computer UniNorth Host-PCI Bridge (rev. 0x00)
obio0 at pci1 dev 23 function 0: addr 0x80000000
enabling KeyLargo internal modem
i2s at obio0 offset 0x10000 not configured
zsc0 at obio0: irq 22,50
zstty0 at zsc0 channel 0
zstty1 at zsc0 channel 1
adb0 at obio0 offset 0x16000 irq 47: 3 targets
aed0 at adb0 addr 0: ADB Event device
akbd0 at adb0 addr 2: PowerBook G3 keyboard
wskbd0 at akbd0: console keyboard, using wsdisplay0
ams0 at adb0 addr 3: EMP trackpad <tpad> 2-button, 400 dpi
wsmouse0 at ams0 mux 0
abtn0 at adb0 addr 7: buttons
apm0 at adb0: battery flags 0x1, 0% charged
battery at obio0 offset 0x0 not configured
backlight at obio0 offset 0xf300 not configured
ki2c1 at obio0
iic1 at ki2c1: I2C bus
wdc0 at obio0 offset 0x1f000 irq 19: DMA transfer
atabus0 at wdc0 channel 0
wdc1 at obio0 offset 0x20000 irq 20: DMA transfer
atabus1 at wdc1 channel 0
wdc2 at obio0 offset 0x21000 irq 21: DMA transfer
atabus2 at wdc2 channel 0
ohci0 at pci1 dev 24 function 0: Apple Computer KeyLargo USB Controller 
(rev. 0x00)
ohci0: interrupting at irq 27
ohci0: OHCI version 1.0
usb0 at ohci0: USB revision 1.0
uhub0 at usb0
uhub0: Apple Computer OHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
ohci1 at pci1 dev 25 function 0: Apple Computer KeyLargo USB Controller 
(rev. 0x00)
ohci1: can't map mem space
uninorth2 at mainbus0
pci2 at uninorth2 bus 0
pci2: i/o space, memory space enabled
pchb2 at pci2 dev 11 function 0
pchb2: Apple Computer UniNorth Host-PCI Bridge (rev. 0x00)
gem0 at pci2 dev 15 function 0: Apple Computer GMAC Ethernet (rev. 0x00)
gem0: interrupting at irq 41
gem0: Ethernet address XX:XX:XX:XX:XX:XX, 10KB RX fifo, 9KB TX fifo
bmtphy0 at gem0 phy 0: BCM5201 10/100 media interface, rev. 2
bmtphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
timecounter: Timecounter "clockinterrupt" frequency 100 Hz quality 0
timecounter: Timecounter "mftb" frequency 16644884 Hz quality 100
Kernelized RAIDframe activated
uhidev0 at uhub0 port 1 configuration 1 interface 0
uhidev0: Logitech USB-PS/2 Optical Mouse, rev 2.00/11.10, addr 2, iclass 3/1
ums0 at uhidev0: 3 buttons and Z dir.
wsmouse1 at ums0 mux 0
wd0 at atabus0 drive 0: <TOSHIBA MK6014MAP>
wd0: drive supports 16-sector PIO transfers, LBA addressing
wd0: 5729 MB, 12416 cyl, 15 head, 63 sec, 512 bytes/sect x 11733120 sectors
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 4 (Ultra/66)
wd0(wdc0:0:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 4 (Ultra/66) 
(using DMA)
atapibus0 at atabus1: 2 targets
cd0 at atapibus0 drive 0: <MATSHITA CR-175, , 5AAE> cdrom removable
cd0: drive supports PIO mode 4, DMA mode 2
cd0(wdc1:0:0): using PIO mode 4, DMA mode 2 (using DMA)
boot device: wd0
root on wd0a dumps on wd0b
root file system type: ffs