From mboxrd@z Thu Jan 1 00:00:00 1970 From: Detlev Zundel Date: Fri, 21 May 2010 11:05:53 +0200 Subject: [U-Boot] Watchdog support for ppc4xx In-Reply-To: <20100520184658.C61D2E67644@gemini.denx.de> (Wolfgang Denk's message of "Thu, 20 May 2010 20:46:58 +0200") References: <201005201355.01964.sr@denx.de> <20100520184658.C61D2E67644@gemini.denx.de> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Wolfgang, > Dear Stefan Roese, > > In message <201005201355.01964.sr@denx.de> you wrote: >> >> > Also I would like to determine in u-boot if a >> > reset was caused by the watchdog timer using the TSR WRS field. If it >> > was reset by the watchdog we will boot into a failsafe partition to >> > protect against system update errors. >> > >> > Has anyone done something like this? >> >> Such a detection is not implemented for PPC4xx. Not sure if it's implemented >> for any other architecture. > > I think lwmon5 performs such checking; eventually this is buryied > somewhere in the POST code. Well, at least I know that for mpc5121 we read the reser status register at boot and copy it to global data (arch/powerpc/cpu/mpc512x/cpu_init.c:64). The value is also output in the U-Boot prompt (arch/powerpc/cpu/mpc512x/cpu.c:68) which is a nice thing IMHO. Checking a "git grep reset_status" one can see that something similar is done for other PowerPC cpus as well, so I'd suggest reusing this method for ppc4xx and providing a mechanism to access this information from a script. Cheers Detlev -- Wenn ein Kopf und ein Buch zusammenstossen und es klingt hohl; ist denn das allemal im Buche? - Lichtenberg -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at denx.de