RE: correct use of bus_dmamap_sync

From: Singh, Vijay (Vijay.Singh_at_netapp.com)
Date: 10/25/05

  • Next message: John Baldwin: "Re: correct use of bus_dmamap_sync" 
    Date: Tue, 25 Oct 2005 10:02:45 -0700
To: "Dinesh Nair" <dinesh@alphaque.com>

    man bus_dma(9)

    > -----Original Message-----
    > From: Dinesh Nair [mailto:dinesh@alphaque.com]
    > Sent: Tuesday, October 25, 2005 7:03 AM
    > To: Dinesh Nair
    > Cc: freebsd-hackers@freebsd.org
    > Subject: Re: correct use of bus_dmamap_sync
    >
    >
    >
    > 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"
    >
    _______________________________________________
    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: John Baldwin: "Re: correct use of bus_dmamap_sync"

    Relevant Pages