Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 13 Dec 2018 11:39:17 +0100
From:      Hans Petter Selasky <hps@selasky.org>
To:        Rajesh Kumar <rajfbsd@gmail.com>, freebsd-drivers@freebsd.org, freebsd-hackers@freebsd.org
Subject:   Re: How to use the DMA Engine in FreeBSD?
Message-ID:  <434ed3ba-6613-b5eb-5a68-f69936bcda21@selasky.org>
In-Reply-To: <CAAO%2BANOty8FeOR7VQdXmxWy5y288pm=Q4cswHJ1BbgT2h1cUWg@mail.gmail.com>
References:  <CAAO%2BANOty8FeOR7VQdXmxWy5y288pm=Q4cswHJ1BbgT2h1cUWg@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On 12/13/18 11:04 AM, Rajesh Kumar wrote:
> Hi,
> 
> Is there any good documentation available to understand the existing
> support, API's and how-to use the DMA Engine in FreeBSD?
> 
> I am trying to write a test driver which will use DMA Engine to do the data
> transfer (rather than plain memcpy which involves cpu).  Can anyone point
> to any driver implementation which has similar functions implemented?  I
> see references to SYS_RES_DRQ to allocate DMA channels and play around. But
> that seems to be specific to ISA. Can it be used for PCI drivers as well?

Hi,

What you are looking for is called PCI busmaster.

--HPS




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?434ed3ba-6613-b5eb-5a68-f69936bcda21>