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Date: Tue, 25 Oct 2005 22:02:44 +0800
From: Dinesh Nair <dinesh@alphaque.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: correct use of bus_dmamap_sync
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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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