Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753951Ab1BIQc6 (ORCPT ); Wed, 9 Feb 2011 11:32:58 -0500 Received: from mx0.aculab.com ([213.249.233.131]:41446 "HELO mx0.aculab.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753552Ab1BIQc5 convert rfc822-to-8bit (ORCPT ); Wed, 9 Feb 2011 11:32:57 -0500 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [PATCH 1/2] misc: add CARMA DATA-FPGA Access Driver Date: Wed, 9 Feb 2011 16:30:23 -0000 Message-ID: In-Reply-To: <1297121021-3522-2-git-send-email-iws@ovro.caltech.edu> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [PATCH 1/2] misc: add CARMA DATA-FPGA Access Driver Thread-Index: AcvHHesaEO51GOw2S4u3gSF5HgD2GABWE5zQ From: "David Laight" To: "Ira W. Snyder" , Cc: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 802 Lines: 23 > This driver allows userspace to access the data processing > FPGAs on the OVRO CARMA board. It has two modes of operation: > > 1) random access > > This allows users to poke any DATA-FPGA registers by using mmap to map > the address region directly into their memory map. I needed something similar, but used pread() and pwrite() to request the transfers. While this does require a system call per transfer, it allows the driver to use dma (if available) to speed up the request. In my case doing single cycle transfers would be too slow. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/