From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfgang Denk Date: Wed, 03 Nov 2004 15:58:11 +0100 Subject: [U-Boot-Users] U-boot for Mips 4KEC In-Reply-To: Your message of "Wed, 03 Nov 2004 18:10:00 +0530." Message-ID: <20041103145816.33530C1430@atlas.denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Pooja, in message you wrote: > > In the process of porting U-boot for Malta which uses mips 4Kec I > discovered that the stack required for intial C environment can neither > be obtained by some on-chip memory (IMMR in MPC8xx ) nor by using DCACHE > in locked mode. Mips 4KC has the DCache locked mode support but Mips > 4KEC has it only through external pin interface. I have o admit that I don't know the details of this specirfic CPU, but are you _really_ sure that there is no way to lock (parts of) the data cache? I would be relly suprised if this was the case... > I am looking for a way of not using the C code till code has started > running from RAM. But how do I get the value of gd(global data pointer) This "way" is a major redesign and rewrite of U-Boot. > which U-boot expects? README file does not mention anything about mips > registers which are specifially used for this purpose. No matter what you do, sooner or later you will find that you need some preliminary stack and eventually storage space for a few variables. So instead of creating several new problems, I recommend to try to fix the root problem first, and all the rest will fall in place. Best regards, Wolfgang Denk -- See us @ Embedded/Electronica Munich, Nov 09 - 12, Hall A.6 Booth 513 Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de An Elephant is a mouse with an Operating System. - Knuth