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    SubjectRe: DMA API issues
    On Fri, 18 Jun 2004 11:07:21 -0700
    Matt Porter <mporter@kernel.crashing.org> wrote:

    > Can't you just implement an arch-specific allocator for your 32KB
    > SRAM, then implement the DMA API streaming and dma_alloc/free APIs
    > on top of that?

    Yes but thats not very generic is it? Im not the only one with this
    problem.

    > Since this architecture is obviously not designed
    > for performance

    What makes you think writes to the 32K SRAM are any slower than to the
    SDRAM? the device is completely memory mapped.

    >, it doesn't seem to be a big deal to have the streaming
    > APIs copy to/from the kmalloced (or whatever) buffer to/from the SRAM
    > allocated memory and then have those APIs return the proper dma_addr_t
    > for the embedded OHCI's address space view of the SRAM.

    Again its a suboptimal solution, and on an architecture where the CPU
    isnt *that* fast in the first place it seems wrong to deliberately
    choose the slowest possible route...
    -
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