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/
    +==========================----oOO--(_)--OOo----==========================+
    | for a in past present future; do                                        |
    |   for b in clients employers associates relatives neighbours pets; do   |
    |   echo "The opinions here in no way reflect the opinions of my $a $b."  |
    | done; done                                                              |
    +=========================================================================+
    _______________________________________________
    freebsd-hackers@freebsd.org mailing list
    http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
    To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org"
    

  • Next message: Singh, Vijay: "RE: correct use of bus_dmamap_sync"

    Relevant Pages

    • RE: correct use of bus_dmamap_sync
      ... > To: Dinesh Nair ... >> the pseudo code for the read and write, called during an interrupt ... To unsubscribe, ...
      (freebsd-hackers)
    • Simple but fast control - Update
      ... and interrupt control as well. ... point the 4 data lines are read) and another for the cycle reset. ... We have an ordinary polling loop running and when it ... serial/usb module on board). ...
      (uk.comp.os.linux)
    • Re: Precision PWM in microcontroller
      ... >> programmed to generate an accurate frequency. ... are basically low cost vs. low jitter. ... A single cycle may have a very bad duty ... consecutive values for the interrupt duration. ...
      (comp.arch.embedded)
    • Re: Visual Frameworks vs. Cells compared to Flow-Based Programming
      ... interrupt request line. ... ION instruction had a one-cycle delay built into it ... were one cycle; memory-reference added a cycle; indirection during ...
      (comp.lang.lisp)
    • Re: Help Z180 Interrupt Vector INT0 Mode 2
      ... Interrupt mode 2 allows you to have up to 128 different interrupt ... interrupt acknowledge bus cycle. ... The processor reads the value on the data bus at the end of the ... RETI instruction at the end of the interrupt service routine and reset ...
      (comp.arch.embedded)