From mboxrd@z Thu Jan 1 00:00:00 1970 From: kenneth johansson Date: Wed, 18 Jun 2008 23:16:04 +0200 Subject: [U-Boot-Users] mpc5121 cache coherency In-Reply-To: <4b73d43f0806181238k4ab0b900w3f18216a5c083248@mail.gmail.com> References: <1213817391.27790.27.camel@localhost.localdomain> <4b73d43f0806181238k4ab0b900w3f18216a5c083248@mail.gmail.com> Message-ID: <1213823764.10172.3.camel@duo> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Wed, 2008-06-18 at 13:38 -0600, John Rigby wrote: > Unlike other SOCs with e300 cores the 5121 is not cache coherent. The > problem is an internal bridge that the processor can not snoop across. I do not have access to the manuals right now but I search all over an this was not something I found. Is this a design decision or an errata for the current version of the chip ? > On Wed, Jun 18, 2008 at 1:29 PM, Kenneth Johansson wrote: > > I have tried to speed up u-boot by turning on I/D cache during boot. > > > > It sort of works and gives quite a boost but I'm having problems with > > the ethernet driver that no longer works. > > > > What I'm seeing is that the cpu do not notice the ethernet hardwares > > updates that is located in DRAM. Basically what is expected from a cache > > incoherent system. > > > > Now my question is should not the e300 core detect writes to the DRAM > > and reload the cached data ?? > > > > --- > > To get cache working I'm turning on the MMU and program some BAT > > registers to a 1-1 mapping where only DRAM has cache on and all other > > memory regions like the IMMR, flash ... has cache off. > > > > > > > > ------------------------------------------------------------------------- > > Check out the new SourceForge.net Marketplace. > > It's the best place to buy or sell services for > > just about anything Open Source. > > http://sourceforge.net/services/buy/index.php > > _______________________________________________ > > U-Boot-Users mailing list > > U-Boot-Users at lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/u-boot-users > > >