From owner-svn-src-head@FreeBSD.ORG Wed Jan 12 21:27:42 2011 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 315B9106566B; Wed, 12 Jan 2011 21:27:42 +0000 (UTC) (envelope-from mdf356@gmail.com) Received: from mail-iw0-f182.google.com (mail-iw0-f182.google.com [209.85.214.182]) by mx1.freebsd.org (Postfix) with ESMTP id C29038FC1F; Wed, 12 Jan 2011 21:27:41 +0000 (UTC) Received: by iwn39 with SMTP id 39so919915iwn.13 for ; Wed, 12 Jan 2011 13:27:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=8yFq3920KIOpvAgNwyCDpznfMCjV1NkpeU3GDJIo1dU=; b=dcRyS5kLpGUGEexRtF87934Zmx3Yz+JsHEYZApnFJPclR5WhwCsm0y+QukuGkWZHN1 nxgalwlaH9DsR7dohJC/jx/hZckAfabQiZH5CqEzkwbTCYtqxmawLaZjX42Ed0L9a09q Ll2rZtiB7kvQjb+M0zJAtwBStBHf0or3SKXRM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=ojCC1LFvM/8WRwROuqAUXhDWmJbx0hlbVQ4c5vh9lNP+CGRgDmAlW8lSf0IeIffBpH SB5papJ2wtF49xldt1EhRgt7uEiZM8KIlv0gOvlKOJWIJmzcXbQnhj4EKecthrH3q5kL KsU5Yc443R3rYvuw3l08LdD1sbn0csVIu2y7A= MIME-Version: 1.0 Received: by 10.231.35.141 with SMTP id p13mr1600193ibd.79.1294867660893; Wed, 12 Jan 2011 13:27:40 -0800 (PST) Sender: mdf356@gmail.com Received: by 10.231.160.147 with HTTP; Wed, 12 Jan 2011 13:27:40 -0800 (PST) In-Reply-To: <201101121621.30371.jhb@freebsd.org> References: <201101122108.p0CL8o3Q012038@svn.freebsd.org> <201101121621.30371.jhb@freebsd.org> Date: Wed, 12 Jan 2011 13:27:40 -0800 X-Google-Sender-Auth: Fq2LgD6VFBd-Z-eiNR0IJFvj1Kw Message-ID: From: mdf@FreeBSD.org To: John Baldwin Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r217330 - head/sys/x86/x86 X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 12 Jan 2011 21:27:42 -0000 On Wed, Jan 12, 2011 at 1:21 PM, John Baldwin wrote: > On Wednesday, January 12, 2011 4:08:50 pm Matthew D Fleming wrote: >> Author: mdf >> Date: Wed Jan 12 21:08:49 2011 >> New Revision: 217330 >> URL: http://svn.freebsd.org/changeset/base/217330 >> >> Log: >> =A0 Fix a brain fart. =A0Since this file is shared between i386 and amd6= 4, a >> =A0 bus_size_t may be 32 or 64 bits. =A0Change the bounce_zone alignment= field >> =A0 to explicitly be 32 bits, as I can't really imagine a DMA device tha= t >> =A0 needs anything close to 2GB alignment of data. > > Hmm, we do have devices with 4GB boundaries though. =A0I think I'd prefer= it if > you instead if you did this: > > #if defined(amd64) || defined(PAE) > #define SYSCTL_ADD_BUS_SIZE_T =A0 =A0 =A0 =A0 =A0 SYSCTL_ADD_UQUAD > #else > #define SYSCTL_ADD_BUS_SIZE_T =A0 =A0 =A0 =A0 =A0 SYSCTL_ADD_UINT > #endif > > and then just used SYSCTL_ADD_BUS_SIZE_T() in the code so we could let th= e > members in the bounce zone retain the same types passed to > bus_dma_tag_create(). But would there be a device that can't start DMA except on a 4GB boundary? I thought that's what this member was for. Thanks, matthew