From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerry Van Baren Date: Mon, 22 Jan 2007 08:58:29 -0500 Subject: [U-Boot-Users] Running U-boot in cache area. In-Reply-To: <576906.40588.qm@web7911.mail.in.yahoo.com> References: <576906.40588.qm@web7911.mail.in.yahoo.com> Message-ID: <45B4C305.3010501@smiths-aerospace.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de sathesh babu wrote: > Hi, > I am tring to run U-boot on MIPS 24KE processor. > I have done MIPS 24KE cache initilization and configured it for > write through mode in the start.S file. > > If I specify SDRAM start address as uncached area ( start > with 0xa0000000), u-boot boots up and able to get the u-boot prompt. > > It I try SDRAM start address as cached area ( Start with 0x80000000), > the u-boot comes up to relocation function and hangs. > > Could you please tell me what could be the problem. > Did i mss any thing?. > > I see the same behaviour with write back mode also. > > Should i call any cache invalidation ( doing this as part of cache > initilization in the start.S) or flush functions before calling > relocation(). > > I am enabling primary cache only and no secondary cache. > > Thanks in advance. > > Regards. > Sathesh This may be the FAQ. Enabling caches typically enables bursting and disabling caches typically disables bursting (I'm not familiar with your MIPS - YMMV). This class of RAM problems tend to show up only when bursting. gvb