From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.207]) by ozlabs.org (Postfix) with ESMTP id 33F752BC0F for ; Wed, 27 Oct 2004 01:48:08 +1000 (EST) Received: by wproxy.gmail.com with SMTP id 43so214661wri for ; Tue, 26 Oct 2004 08:48:07 -0700 (PDT) Message-ID: <35fb2e5904102608487acce066@mail.gmail.com> Date: Tue, 26 Oct 2004 16:48:06 +0100 From: Jon Masters To: Peter Ryser In-Reply-To: <417DE312.6070405@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII References: <1098701468l.31592l.0l@ipnnarval> <417D2B5E.8050200@xilinx.com> <35fb2e59041025140776cfe174@mail.gmail.com> <417DE312.6070405@xilinx.com> Cc: linuxppc-embedded@ozlabs.org Subject: Re: uboot and ppc405 Reply-To: jonathan@jonmasters.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 25 Oct 2004 22:39:30 -0700, Peter Ryser wrote: jcm>> btw Peter, I've been moaning about the weird interrupt behaviour of jcm>> the SysACE on e.g. the Memec board for some time (see archives for jcm>> various other people's experiences too) - and I've spoken to several jcm>> folks at Xilinx without getting very far. If there's a fundamental jcm>> problem then it probably makes sense for us to help get it fixed. > Hmm, I'm not aware of any interrupt problems with System ACE CF. It issues an extra interrupt after each sector write on our hardware, in what seems to be a reasonably reproducible but not entirely predictable fashion. This is after the interrupt we expect to get on sector completion - it causes the Monta driver to go belly up because it has no handling to check for interrupt on QUEUE_EMPTY or similar error conditions. I have every confidence that it works on the ML300, just not on other boards, including both the Memec board and our in house prototypes. Since it's not a major issue right now to have good performance from the SysACE (just a reliable driver), I've created the patch I posted previously to use polled IO instead. > There is now a MVL preview kit for the Memec board. You might want to > try it out and see whether the problems you observe persist. Is this the one which doesn't actually use the SystemACE for a filesystem? > Looking at the postings back in April I can only say that I never saw > any similar problems. Others have done so. I'll check with the hardware guys and see if I can't send you a simple hardware case that falls over at some point - I'm slightly constrained to release hardware designs and so on until after this thing is ready to ship. > The implementation of System ACE CF functionality in U-Boot is written > for polled operation. In that case Stephen Williams wrote the actual > driver and we decided not to publish our own driver but reuse his. So it probably doesn't use the Xilinx HAL, that can only be a good thing :-) Jon.