From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from yw-out-2324.google.com (yw-out-2324.google.com [74.125.46.30]) by ozlabs.org (Postfix) with ESMTP id 5BD17DDF3D for ; Sun, 8 Mar 2009 14:15:15 +1100 (EST) Received: by yw-out-2324.google.com with SMTP id 5so490142ywb.39 for ; Sat, 07 Mar 2009 19:15:13 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1236462686.7260.161.camel@pasglop> References: <64ac01180903052032i75792fa6x864f91c511b3f228@mail.gmail.com> <64ac01180903052138k4226022cq840d497dccecd939@mail.gmail.com> <64ac01180903052210r2aee7246g50fd0656c491a40b@mail.gmail.com> <64ac01180903060812n1f355207lb3fa6de3ed17ae41@mail.gmail.com> <1236462686.7260.161.camel@pasglop> Date: Sat, 7 Mar 2009 21:15:13 -0600 Message-ID: <64ac01180903071915lf27669fq813a5e3842c0c2a1@mail.gmail.com> Subject: Re: 83xx: Marking or Allocating Pages as Cache-Inhibited From: Ben Menchaca To: Benjamin Herrenschmidt Content-Type: multipart/alternative; boundary=00221532c5b41fd9ba046492edd7 Cc: linuxppc-dev@ozlabs.org, Liu Dave-R63238 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --00221532c5b41fd9ba046492edd7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit On Sat, Mar 7, 2009 at 3:51 PM, Benjamin Herrenschmidt < benh@kernel.crashing.org> wrote: > On Fri, 2009-03-06 at 10:12 -0600, Ben Menchaca wrote: > > Testing now...it looks like it (almost) works, though! Why does > > setting no-snoop cause snooping to work? More on the effect on > > setting that bit in a few minutes...need more testing. > > Maybe they got the documentation for that bit backward ? :-) For posterity...it does appear that this is the case. I don't have a bus analyzer to watch the transaction, but a JTAG trigger caught the update happening if and only if bit 3 was set in the (R|W)DMA descriptor. My FAE at FS said he is watching this thread, so hopefully some doc errata can be generated so others can avoid my confusion :-). - Ben --00221532c5b41fd9ba046492edd7 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
On Sat, Mar 7, 2009 at 3:51 PM, Benjamin Herrens= chmidt <be= nh@kernel.crashing.org> wrote:
On Fri, 2009-03-06 at 10:12 -0600, Ben Menchaca wrote: > Testing now...it looks like it (almost) works, though! =A0Why does
> setting no-snoop cause snooping to work? =A0More on the effect on
> setting that bit in a few minutes...need more testing.

Maybe they got the documentation for that bit backward ? :-)

For posterity...it does appear that this is the case.=A0 I don= 't have a bus analyzer to watch the transaction, but a JTAG trigger cau= ght the update happening if and only if bit 3 was set in the (R|W)DMA descr= iptor.=A0 My FAE at FS said he is watching this thread, so hopefully some d= oc errata can be generated so others can avoid my confusion :-).

- Ben

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