From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 24 Jun 2003 14:19:35 -0500 From: Chris Zimman To: Oliver Amft Cc: linuxppc-embedded@lists.linuxppc.org Subject: Re: PCI DMA memory problem Message-ID: <20030624191935.GA9845@dingdong.cryptoapps.com> Reply-To: Chris Zimman References: <3EF8A001.2090603@gmx.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <3EF8A001.2090603@gmx.net> Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: On Tue, Jun 24, 2003 at 09:01:21PM +0200, Oliver Amft wrote: > > I am implementing a network driver for a DMA device on a custom > 405GP/GPr based board. The networking device is attached over PCI bus. > Kernel is currently 2.4.21. BIOS is PPCBoot 1.2.0. > > To map the data buffers from skb the driver uses pci_map_single(). When > starting the kernel with SDRAM size configurations other than 32MByte > the device is unable to transfer data (currupted data) - descriptor > dword read/write-back works (set up with pci_alloc_consistent()). For > the kernel start option mem=32MB everything is fine (descriptor + > correct data). My first thought is -- is/are the SDRAM bank(s) configured correctly? I don't know that it'd necessarily be related, but for the 405GP, PPCBoot 1.2.0 doesn't have the PCI bridge setup quite right for all PCI devices (eg. 82559 won't work). I have code to fix the bridge setup if you need it -- although I'm not even certain they exist in the GPR. --Chris ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/