Re: correct use of bus_dmamap_sync

From: Dinesh Nair (dinesh_at_alphaque.com)
Date: 10/25/05

  • Next message: Singh, Vijay: "RE: correct use of bus_dmamap_sync"
    Date: Tue, 25 Oct 2005 22:02:44 +0800
    To: Dinesh Nair <dinesh@alphaque.com>
    
    

    On 10/25/05 21:15 Dinesh Nair said the following:
    > the pseudo code for the read and write, called during an interrupt
    > cycle, are:
    >
    > rx_func()
    > {
    > POSITION A
    >
    > while(there_is_some_data) {
    > memcpy(somebuf, readbuf)
    > }
    > POSITION B
    > }
    >
    > tx_func()
    > {
    > POSITION C
    >
    > while(there_is_some_data) {
    > memcpy(writebuf, somebuf)
    > }
    > POSITION D
    > }
    >
    > the question is, what op should i use for bus_dmamap_sync in positions
    > A, B, C and D ?

    responding to my own request, i mean which of BUS_DMASYNC_PREREAD,
    BUS_DMASYNC_POSTREAD, BUS_DMASYNC_PREWRITE, BUS_DMASYNC_POSTWRITE should i
    use, and where ?

    -- 
    Regards,                           /\_/\   "All dogs go to heaven."
    dinesh@alphaque.com                (0 0)    http://www.alphaque.com/
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  • Next message: Singh, Vijay: "RE: correct use of bus_dmamap_sync"

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