On my board the oscillator is marked 50.000 and the 50000000 setting works on my board with Linux 2.4 ... but I meant to ask in my question: whether (may be) the current 8xx vs 2.6 kernel memory initialization problems only showing themself at 50Mhz and not at 48Mhz (I am trying to find explanation why 2.6 works on RPX-Lite - per Tom and Steve).
-----Original Message----- From: John W. Linville [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 3:29 PM To: Povolotsky, Alexander Cc: 'Mark Chambers'; 'linuxppc-embedded at ozlabs.org'; 'Tom Rini'; 'Steven Blakeslee' Subject: Re: Linux 2.6.10-rc3 8xx: debugging (over-writing) content of b d_in fo structure in the kernel booting code On Tue, Jan 18, 2005 at 02:08:19PM -0500, Povolotsky, Alexander wrote: > My board is using: > > bd->bi_intfreq = 50000000; > bd->bi_busfreq = 50000000; > > While RPX-Lite is using > > bd->bi_intfreq = 48000000; > bd->bi_busfreq = 48000000; > > Is this what makes RPX-Lite work and my (MPC 880) not ? That, of course, depends on which value is correct for your board... :-) When I mentioned in one of our (possibly off-line) exchanges that _slightly_ incorrect clock speeds might explain how you get a few good characters from the serial port before you get all that garbage, this is the kind of descrepancy I was suggesting. There may be enough "slop" in the timings of the relatively slow serial port to make 48MHz and 50MHz "close enough" for a few characters. So, what is the correct number for your board? Do you know how to identify an oscillator? They have a bit of a 'tin can' look to them. Find the one closest to the CPU on the board, and see what number is on it. John -- John W. Linville linville at tuxdriver.com
