From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail19c.g19.rapidsite.net (mail19c.dulles19-verio.com [204.202.242.56]) by ozlabs.org (Postfix) with SMTP id 2CD20679F7 for ; Tue, 14 Feb 2006 15:02:27 +1100 (EST) Received: from mx32.stngva01.us.mxservers.net (204.202.242.10) by mail19c.g19.rapidsite.net (RS ver 1.0.95vs) with SMTP id 4-0532349744 for ; Mon, 13 Feb 2006 23:02:25 -0500 (EST) From: "Russell McGuire" To: Subject: 82xx_io UART BRG's vs BUS CLK Date: Mon, 13 Feb 2006 20:02:17 -0800 Message-ID: <000e01c6311b$72e535e0$6405a8c0@absolut> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" In-Reply-To: List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Anyone, Recently I found that the value I was passing to Linux for the BUS CLK frequency was incorrect. Previously I was passing in from U-boot (66 * 1000 * 1000) 66Mhz, it had been brought up this can cause incorrect SOF transmission rates with the 82xx USB driver, so after measuring our 'exact' clock, I made the adjustment to ( 66,666,666 Hz ) 66.66Mhz . Hoping this would correct the issue, however now I cannot run the serial console baud rate (on SMC2) any higher than 115200 without corruption, however 57600 works on. This worked great before I changed the U-boot BUS clock to the correct value. I did some math on the BRG calculations and with 66Mhz the BRG divisor is 17.8 I am assuming 17 gets written, and with 66.666Mhz then its 18.02 so thus 18 probably gets written. Should perhaps a constant minus 1 be added to the code? Using: U-boot 1.1.2 DENX Linux 2.4.25 Is anyone aware of similar issues, or are there bug fixes past the 2.4.25 Kernel for this? -Russ