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Rockbox mail archiveSubject: Re: PP502x cache bug and ATA DMA test buildRe: PP502x cache bug and ATA DMA test build
From: Boris Gjenero <boris.gjenero_at_gmail.com>
Date: Sat, 04 Feb 2012 13:28:22 -0500 On 03/02/2012 8:43 PM, Michael Sevakis wrote: > For H10 20GB, dircache init and database init seem to pass alright where > as before with DMA it would fault frequently. It's running UDMA 2. Thanks for testing. It's nice to see that DMA is working better now. UDMA 2 is the maximum set at compile time because that's the fastest mode that works at 30 MHz. UDMA 4 can work at 80 MHz, but at least with MK3008GAL, it's not really helpful. (In http://www.rockbox.org/tracker/task/9708?getfile=19063 even UDMA 1 at 24 MHz is very close to the drive's top read speed.) In the OF, it seems DMA is only used at 80 MHz. When I first started investigating the DMA problems, I thought that use of DMA at 30 MHz or changing of boost state during DMA could be responsible for instability. However, according to my tests, UDMA 2 seems totally stable at 30 MHz and when changing between 30 and 80 MHz during DMA. Best regards, Boris Received on 2012-02-04 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |