Am Donnerstag, 21. April 2005 21:31 schrieb David Joy: > On Thu, 21 Apr 2005, Peter Teichmann wrote: > > Am Donnerstag, 21. April 2005 01:46 schrieb David Joy: > >> On an entirely unrelated note, do you know if it is possible to get DMA > >> working on a RiscPC? > > > > In which context? > > > > Peter Teichmann > > Sorry - on the hard disk (a modern UDMA disk on the built-in RiscPC IDE > controller). > > riscpc:~# hdparm -d1 /dev/hda > > /dev/hda: > setting using_dma to 1 (on) > HDIO_SET_DMA failed: Operation not permitted > using_dma = 0 (off)
Oh, I didn't know that you don't know that. That can not work. The hardware of the RiscPC only supports a (strange variant of a) PIO mode. This limits data rates to around 2MB/s, and takes 100% cpu time during that. I think there is support for DMA on other IDE interfaces, but as I do not have one I never tried. Peter Teichmann -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
