From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qy0-f21.google.com (mail-qy0-f21.google.com [209.85.221.21]) by ozlabs.org (Postfix) with ESMTP id 8D8EADDD01 for ; Tue, 2 Dec 2008 06:19:41 +1100 (EST) Received: by qyk14 with SMTP id 14so4344078qyk.9 for ; Mon, 01 Dec 2008 11:19:38 -0800 (PST) Message-ID: Date: Mon, 1 Dec 2008 20:19:38 +0100 From: "Leon Woestenberg" To: "Benjamin Herrenschmidt" Subject: Re: ppc4xx: u-boot sees PCIe endpoint, linux does not. In-Reply-To: <1228119152.7356.118.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 References: <1228119152.7356.118.camel@pasglop> Cc: u-boot@lists.denx.de, Linux PPC List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hello all, On Mon, Dec 1, 2008 at 9:12 AM, Benjamin Herrenschmidt wrote: > On Fri, 2008-11-28 at 13:50 +0100, Leon Woestenberg wrote: >> >> AMCC PPC460EX canyonlands board with an FPGA PCIe end point: >> >> u-boot sees the end point, but Linux does not: >> >> U-Boot 1.3.3-00249-ga524e11 (Jun 30 2008 - 16:05:51) >> CPU: AMCC PowerPC 460EX Rev. A at 800 MHz (PLB=200, OPB=100, EBC=100 MHz) >> <...> >> Board: Canyonlands - AMCC PPC460EX Evaluation Board, 2*PCIe, Rev. 16 >> <...> >> PCIE1: successfully set as root-complex >> 02 00 2071 2071 00ff 00 >> >> Now, if I re-program the end-point FPGA during the u-boot boot >> time-out, Linux will recognize the end-point. >> > It's possible that either the reset in between goes bonkers or something > else causes your FPGA to stop responding. It looks like a programming > problem with the FPGA to me. > I have verified that the end point does not receive any kind of reset. Also, this problem only happens on the Canyonlands board; on x86 and powerpc MPC8315E it remains properly working after soft/hard resets, u-boot init etc. Could it be u-boot overwrites a too large payload into the config space or something similar, which makes subsequent accesses fail? Regards, -- Leon