From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: 750 and Discovery II coherency with PCI.... From: Benjamin Herrenschmidt To: "Steven J. Hill" Cc: linuxppc-dev list In-Reply-To: <410F05EC.1040405@realitydiluted.com> References: <410F05EC.1040405@realitydiluted.com> Content-Type: text/plain Message-Id: <1091580163.1922.39.camel@gaston> Mime-Version: 1.0 Date: Wed, 04 Aug 2004 10:42:44 +1000 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Tue, 2004-08-03 at 13:26, Steven J. Hill wrote: > Greetings. > > I am writing a device driver for a PMC card that is nothing > fancy. It is not a PCI-X card though. My Linux driver properly > detects the device, 'ioremaps' the PCI IO and MEM regions then > attempts to start writing the devices registers for setup > and configuration. I am not getting valid reads and there > appears to be some coherency issues. I have verified that no > other drivers or resources in the system are utilizing the > addresses that are returned to me from 'ioremap'. I have the > following code snippet: There is no coherency issues with non cacheable (ioremap'ed) access of that kind... Note that if you are dealing with IO space, then you should use inX/outX accessors and not ioremap. Ben. ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/