Hi all,

If you are running a 2.6.18 kernel with ivtv-0.8, then I'd appreciate it 
if you can test the following beta driver:

http://dl.ivtvdriver.org/ivtv/unstable/ivtv-b3489.tar.gz

Note that this driver does NOT support the on-screen display of the 
PVR350, so the Xdriver won't work. It also doesn't support TV-out. 
Basically all the decoding code needed to support the PVR350 is not 
functioning (most likely it will crash the driver), instead I've been 
concentrating on getting the MPEG encoding working well.

The key test issue with this driver is whether doing simultaneous MPEG 
and sliced VBI capturing is now working reliably. The core of the 
driver has been changed substantially, ensuring that the interrupt 
handler is doing all the DMA transfers (that used to be in 
user-threads). The PIO transfers for sliced VBI are also done in the 
interrupt handler. I hope this will not cause any problems, I have a 
CPU load of around 1% with PIO, so for me at least there doesn't seem 
to be any performance problem.

Regarding DMA problems: this is partially solved. Part of the problem is 
simply broken hardware and there isn't much I can do about it. I do 
have some code that is supposed to reset the DMA engine when it gets 
stuck, but I haven't tried that yet. The other part is that the use of 
user-threads for DMA can be too slow, causing (probably) DMA queueing 
issues in the firmware of the card followed by DMA engine hangs. That 
part should be fixed with this beta version. In particular this means 
that it is likely that the PVR500 will now work without any DMA hangs. 
(The PCI bridge on the PVR500 seems to work around the hardware 
problems of the DMA engine)

I would like to get feedback on the following issues:

1) How well does Closed Captioning work with this driver? I've been 
unable to test that so I'm really curious about it. Under no 
circumstance should MPEG capturing suffer from simultaneous VBI 
capturing.

2) At the top of ivtv-irq.c there is a SLICED_VBI_PIO define. After 
testing with the current value (1), please also do a test with this 
value set to 0. This will do VBI transfers using DMA. I seem to get the 
occasional missing VBI frame (only when also capturing MPEG at the same 
time), but it is really hard to test without access to Closed 
Captioning. The MPEG stream should remain OK, regardless of what's 
happening with the VBI stream.

3) Is it still possible to hang the driver on a PVR500?

Please note that this is a beta driver, so don't use it for anything 
important!

Thanks,

        Hans

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