From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Williams Date: Sat, 06 Mar 2004 22:25:32 -0800 Subject: [U-Boot-Users] PPC405GPr reset troubles Message-ID: <2771-13523@sneakemail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de This may be slightly off-topic, but the hardware is as right as I can get it, so I'm looking for some sort of software problem. I am having trouble with the "reset" command, and the /SysReset in particular, in connection with the EBC clock settings. The PSR (Pin Strapping Register) is spontaneously changing values on the /SysReset. In particular, the external bus clock divisor is changing from /4 to /2. I've added a dump of the PSR right where U-Boot prints the CPU speeds, and I get the following: U-Boot 1.0.2 (Mar 5 2004 - 17:03:00) XXXX PSR=0xfdfc0ce0 CPU: IBM PowerPC 405GPr Rev. B at 266.500 MHz (PLB=133, OPB=33, EBC=33 MHz) PCI sync clock at 33 MHz, internal PCI arbiter enabled 16 kB I-Cache 16 kB D-Cache [...etc...] ?> reset U-Boot 1.0.2 (Mar 5 2004 - 17:03:00) XXXX PSR=0xfdf80ce0 CPU: IBM PowerPC 405GPr Rev. B at 266.500 MHz (PLB=133, OPB=33, EBC=66 MHz) PCI sync clock at 33 MHz, internal PCI arbiter enabled 16 kB I-Cache 16 kB D-Cache I see with an O'Scope that the EMCTxEN signal (which is the difference between PSR values) is really low during the /SysReset, and it is clearly stable low then. But the PSR is read-only? Why is my PSR wrong? -- Steve Williams "The woods are lovely, dark and deep. steve at XXXXXXXXXX But I have promises to keep, http://www.XXXXXXXXXX and lines to code before I sleep, http://www.picturel.com And lines to code before I sleep."