From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Subject: Re: Decode dimms on dual socket machines Date: Tue, 19 Apr 2011 14:24:37 +0200 Message-ID: <20110419142437.5eaac154@endymion.delvare> References: <4DA4250A.3060907@fuckner.net> <20110412132611.045ace21@endymion.delvare> <4DA44B05.906@fuckner.net> <20110412155345.4644e51c@endymion.delvare> <4DA53F22.5020105@gmx.de> <20110413103952.68bdb6fa@endymion.delvare> <4DA575C3.1050100@fuckner.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4DA575C3.1050100-iWcS09LKDTLR7s880joybQ@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Michael Fuckner Cc: Michael Lawnick , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org Hi Michael, On Wed, 13 Apr 2011 12:06:59 +0200, Michael Fuckner wrote: > On 04/13/2011 10:39 AM, Jean Delvare wrote: > > >> The challenge will be to detect which of the 8 supported devices ( > >> pca_9540, pca_9542, pca_9543, pca_9544, pca_9545, pca_9546, pca_9547, > >> pca_9548) is actually to be used. > > > > In Michael's case it is irrelevant anyway, as the information he found > > meanwhile clearly indicates that bus multiplexing is achieved by GPIOs > > (most certainly on the ICH10) and not an PCA954x chip. The chip at 0x70 > > is probably the Intel 5500 IOH. > > > Supermicro just gave me the following information: > > To access all SPDs, you have to pull low GPIO49 (IO_0x528 bit 17) first. > Then pull low GPIO52 (IO_0x528 bit 20) to access first CPU > memory(0x50~0x55); pull high GPIO52 to access 2nd CPU memory(0x50~0x55). > > > I can't find anything about GPIO49/52,53 in Datasheet for 5500/5520 chipset > http://www.intel.com/assets/pdf/datasheet/321328.pdf > > So it is probably connected to ICH10 > http://www.intel.com/Assets/PDF/datasheet/319973.pdf > > but I don't know how to use this information I've written a kernel driver to gain access to the GPIO pins of the ICH10 (and previous ICH chips too.) It's available here: http://khali.linux-fr.org/devel/misc/i801_gpio/ Generic instructions for standalone drivers are here: http://khali.linux-fr.org/devel/misc/INSTALL I would appreciate if you could give it a try on your system and report everything in the kernel log after loading the driver. By default it won't change the GPIO values so it should be totally safe. Thanks, -- Jean Delvare http://khali.linux-fr.org/wishlist.html