From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 24 Feb 2000 17:17:16 +0100 From: Andreas Bombe To: "Maxim S. Shatskih" Cc: Albrecht Dreß , FireWire devel , LinuxPPC-Dev Liste Subject: Re: FireWire + Apple PB G3: some success Message-ID: <20000224171715.B2137@storm.local> References: <38B3B564.CBA71EC0@mpifr-bonn.mpg.de> <20000224005839.A2784@storm.local> <002801bf7e71$24c2e5a0$0100000a@sauron> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <002801bf7e71$24c2e5a0$0100000a@sauron>; from maxim@storagecraft.com on Thu, Feb 24, 2000 at 05:44:53AM +0300 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Thu, Feb 24, 2000 at 05:44:53AM +0300, Maxim S. Shatskih wrote: > > It's not seen because the driver is stuck in bus reset. The most > > probable reason is that DMA is not working. I can't think of a reason > > right now (since it does work on another PPC). > > I've had this problem on NT4. Are you sure that the DMA enable bit in PCI > config space is set? To quote Albert's patch: + pci_read_config_word (dev, PCI_COMMAND, &w); + pci_write_config_word (dev, PCI_COMMAND, w | PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY | PCI_COMMAND_IO); He sets the PCI master flag (which should be the only thing disabling / enabling DMA in general). In the standard sources pci_set_master() is used, which does the same. Setting PCI_COMMAND_IO on the other hand is unneccessary since the PCILynx only uses memory mapped I/O (if I understand PCI config correctly). I don't know if this flag is harmful if there are no I/O ports. -- Andreas E. Bombe http://home.pages.de/~andreas.bombe/ DSA key 0x04880A44 ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/