From owner-freebsd-arm@freebsd.org  Fri Mar 31 14:01:02 2017
Return-Path: <owner-freebsd-arm@freebsd.org>
Delivered-To: freebsd-arm@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id C50F6D2715A
 for <freebsd-arm@mailman.ysv.freebsd.org>;
 Fri, 31 Mar 2017 14:01:02 +0000 (UTC) (envelope-from mw@semihalf.com)
Received: from mail-it0-x22f.google.com (mail-it0-x22f.google.com
 [IPv6:2607:f8b0:4001:c0b::22f])
 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))
 (Client CN "smtp.gmail.com",
 Issuer "Google Internet Authority G2" (verified OK))
 by mx1.freebsd.org (Postfix) with ESMTPS id 9C14F16
 for <freebsd-arm@freebsd.org>; Fri, 31 Mar 2017 14:01:02 +0000 (UTC)
 (envelope-from mw@semihalf.com)
Received: by mail-it0-x22f.google.com with SMTP id e75so13243337itd.1
 for <freebsd-arm@freebsd.org>; Fri, 31 Mar 2017 07:01:02 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=semihalf-com.20150623.gappssmtp.com; s=20150623;
 h=mime-version:from:date:message-id:subject:to;
 bh=Hv/fpZ8HuiEV/LIjra9DqFtQfDMxLAg2OQrj17l3qqg=;
 b=YrzCckues7gixTKTV77IlSzPMpcTHx9mAttS30dgcU8wG26uS0l/AllMSXnV/UxV++
 dE7ylFDEk3n2wLXvrLjePEIHb9L3PIncoxj7Wts81XFvyxuAjlhFM9a5MqxamPR+f0uB
 Len9tPU/+HCDkKMvXmzc/e4IdgEtZj49gUXpGC8Fav2JrcT/V5G/k4dlLVqwDE49Hw5N
 kb6zydo8SSsiERFjrkghHipVa7+SgkKNvAsRdYJWyHAvA0jJV7pqeEpay9e6h5L8RvWM
 FbEzt3fHpdvcofKEK7lkuxJLSlIlkdMkhhi1Mauze1v5Ypajn8uyIU+HERCQlFIQKc5P
 VBgQ==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20161025;
 h=x-gm-message-state:mime-version:from:date:message-id:subject:to;
 bh=Hv/fpZ8HuiEV/LIjra9DqFtQfDMxLAg2OQrj17l3qqg=;
 b=BA0RcnMISQ3dLxUB3JbZgUIv7outLg8ikr2ec2d3tlGMahJU0H+j1xkrLwEsUbsi57
 zYNPnHuv2qsQy1awWrpjWy701BKACPGs2gpO1JwHEYpicnkhnQHXa6tOQBc+DqtTT85g
 AGiZdlPMpFyH04EZCK3pM2p5czjFfLH55nSIhLNF8wLq6tKkEocEWWc8cQ24Rk/6w+La
 tiyGyAQMhnDn0ZCXhYoW0fQ4CG55lY7kYXwn/fpmr64rEOAD2BgF5N266j5f8TPyGmOG
 ZlulCONJHW+WNeAGSERNT1e4tWILK+DUmTH7KBDio78AjNiU0uZ3V5KItDrzlNoqkEj5
 c4HQ==
X-Gm-Message-State: AFeK/H3s82H3irJA6DDpQaR0VDYcQI5HDEBMFUHvUPirDg/7qvCGhAK9RyW+0YmavI+dy+L1w13JFVInnSN2bg==
X-Received: by 10.36.137.68 with SMTP id s65mr3081161itd.70.1490968861324;
 Fri, 31 Mar 2017 07:01:01 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.107.169.146 with HTTP; Fri, 31 Mar 2017 07:01:00 -0700 (PDT)
From: Marcin Wojtas <mw@semihalf.com>
Date: Fri, 31 Mar 2017 16:01:00 +0200
Message-ID: <CAPv3WKejupH4JG1=_XV6PknnKifxbF0qoVubtMRVtZWEoBZ7xg@mail.gmail.com>
Subject: Coherent bus_dma for ARMv7
To: freebsd-arm@freebsd.org
Content-Type: text/plain; charset=UTF-8
X-BeenThere: freebsd-arm@freebsd.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: "Porting FreeBSD to ARM processors." <freebsd-arm.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-arm>,
 <mailto:freebsd-arm-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-arm/>
List-Post: <mailto:freebsd-arm@freebsd.org>
List-Help: <mailto:freebsd-arm-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-arm>,
 <mailto:freebsd-arm-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 31 Mar 2017 14:01:02 -0000

Hi,

In current FreeBSD-HEAD ARMv7 platforms, which support hardware IO
cache coherency cannot make use of this feature. In our project we
implemented coherent variant bus_dma, which is basing on x86 and arm64
approach. Using of above solution is not obligatory and depends on
setting newly added option for that purpose.

Needless to say, our platform (Marvell Armada 38x) IO performance
boosted after switching to it. Do you wish to enable such option in
HEAD?

Regards,
Marcin