Date: Sun, 02 Jan 2005 00:21:42 +0100 From: Philip Nienhuis <[EMAIL PROTECTED]> Subject: Re: [LIB] dma
john wrote: > > Date: Sat, 1 Jan 2005 07:40:32 -0600 (GMT+6) > From: john <[EMAIL PROTECTED]> > Subject: Re: [LIB] dma > > On Fri, 31 Dec 2004, Philip Nienhuis wrote: > > > Date: Fri, 31 Dec 2004 17:35:00 +0100 > > From: Philip Nienhuis <[EMAIL PROTECTED]> > > Subject: Re: [LIB] dma > > > > John Musielewicz wrote: > >> > >> Date: Tue, 28 Dec 2004 09:07:48 -0800 (PST) > >> From: John Musielewicz <[EMAIL PROTECTED]> > >> Subject: dma > >> > >> I was messing around with the kernel in linux v. 2.6.9 > >> and now when my libby 110CT boots it reports that my > >> hard drive isn't using dma. I have a 60GB toshiba > >> installed without overlay. I checked the kernel and I > >> have everything selected to use dma but I had the > >> intel driver installed for the hard drive but I don't > >> believe it uses that. does anyone know what driver I > >> should install? The drive is ok for speed without dma > > > > If you care to take a look on > > http://www.photoengineering.com/laptop/L100mm.pdf, > > (your own site isn't it) you'll see in Fig. 1-3 that the Libretto's > > internal HDD is on the 16 bit ISA bus. A 16 bit ISA bus doesn't support > > DMA :-( DMA is only possible on 32-bit PCI buses. > > > > 16 bit busses do support dma but for some reason its not connected on the > hard drive. For example the sound chip is on the same isa mini bus and > it has dma support in the bios. There are 2 dma lines in a standard 44 pin > ide line > (which is what the libby uses) and for some reason they are not connected > which translates into half speed for the hard drive. It should be going at > 5MB per sec and is only getting 2.5. You are right, I am wrong. And you found a good explanation that the Lib does not support dma: unconnected IDE lines. Which also explains heavy CPU load when doing disk I/O. If you manage to connect the dma pins, you might need to upgrade the BIOS too, as I think there might be some PnP involved to sort out dma channel selection of all devices. Or do you think it can be hard-wired? Would the famous Dr Xin have a hint? (www.fixup.net) > > FWIW, I usually select "Generic IDE" when compiling Linux kernels. > > > Do you enable a 66MHz bus for the libby? I enabled 32 bit access and it > seems to mess things up with 16bit bus and 66 MHz. No, as the ISA bus is not 66 Mhz (I think it is only 12 Mhz or so.) BTW why enable 32-bit access as the HD is on a 16-bit bus anyway? > >> but it is too slow to play movies and I really like > >> watching them on the libby--it has such a nice screen. > >> I can get them to work but I have to reduce the > >> resolution and that sucks. Thanks for any help--I'd > >> really like to get this working!! > > > > DMA is supported on the cardbus slots (but then again I've read > > somewhere they use event polling rather than IRQ). In line with this, > > I've noticed faster I/O on the cardbus slots than on the internal > > HDD.... (but not much faster.) > > I tried running a movie off the cardbus slots once the hd got slow and it > wouldn't do it very well. the flashcard i/o was so slow the sound was > running double speed as compard to the video Ah, flash card.... I use a DVD player, which has a (claimed) sustained data rate (reading) of 4.5 to 10 MB/s. I can't check this figure but DVD playing is not too bad on my 110 (but not quite perfect). > > > > Using a cardbus CDRW/DVD combo (Freecom Traveler II+), DVD playback > > under Win2K on a L110 is a bit choppy but not so much that all fun is > > spoiled..... (save for the noise of the combo player). > > > > I can't play movies at all under windows. neither sound nor video will > run. even just sound (mp3s) is so bad--choppy, slow, hangs--nasty to > listen to. Time to try Vorck's stripped Win2K? or use a less demanding MM-player (I use WMP 6.4 patched to play DVDs). I found VectorLinux 4.3 to be quite fast. However installing all required DVD playing stuff more or less defeats the purpose of such a light-weight Linux install :-( Besides, Linux doesn't recognize my Freecom DVD player, it seems Freecom has invented another proprietary protocol for cardbus/IDE. A pity as the USB interface (selected by simply exchanging the PCMCIA cable for a USB one) works very well. The OS which is by far the fastest on my Lib110 til now is OS/2, esp. with the latest kernels of last summer. However it can't use the cardbus slots very well, the OS/2 Toshiba socket driver dates back to 1994 I think.... :-( Philip
