From mboxrd@z Thu Jan 1 00:00:00 1970 To: Dan Malek Cc: laurent.pinchart@capflow.com, linuxppc-embedded@lists.linuxppc.org Subject: Re: linux-2.4.18 & copy-back cache mode From: Wolfgang Denk Mime-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 In-reply-to: Your message of "Wed, 06 Mar 2002 11:28:39 EST." <3C8643B7.60506@embeddededge.com> Date: Wed, 06 Mar 2002 18:09:41 +0100 Message-Id: <20020306170947.078ED109EB@denx.denx.de> Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: In message <3C8643B7.60506@embeddededge.com> you wrote: > > it was tracked down to a UPM/SDRAM timing problem. People keep talking > about running > 50 MHz bus on these newer parts, is there something > different about the memory controller that allows this and may cause > compatibility problems? I have (fortunately :-) not looked at this > level of detail in the newer parts. There are no differences AFAIK. It's just a faster CPU that allows 66 or even 76 MHz with 1:1 CPU/bus clock mode. We have a MPC823E system here that runs at 66 MHz, and I will have a MPC855T at 66MHz in 18 hours from now. So far I didn't encounter any problems - of course you have to adjust the UPM tables and what else you need to initialize the memory controller. Wolfgang Denk -- Software Engineering: Embedded and Realtime Systems, Embedded Linux Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd@denx.de The Wright Bothers weren't the first to fly. They were just the first not to crash. ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/