Messages in this thread | | | Date | Tue, 11 Aug 2009 10:43:02 +0200 | From | "Emilio G. Cota" <> | Subject | Re: [patch 1/5] Staging: VME Framework for the Linux Kernel |
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Martyn Welch wrote: > Emilio G. Cota wrote: >> Again, he (the driver writer) should know *nothing* about that. >> >> As for the scatter-gather case, what should happen is: >> >> User: hey, there's a buffer I want to transfer. here's >> a pointer and size > Buffer where? On VME or PCI, where are you transferring it to? The API I > have will allow scattered locations on VME to be copied to PCI and > visa-versa, scattered locations on PCI to be copied to VME and > visa-versa. Even scattered locations on VME to scattered locations on > PCI with a bit of effort.
Admittedly our current tsi148 driver deals with the most common situation: DMA from main (master) CPU RAM to/from a VME slave.
I'm not claiming we shouldn't support sg lists; however the implementation should resemble the existing sg interfaces. I'm currently working on something along those lines.
Thanks, E.
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