From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <17648569.1173693688643.JavaMail.ngmail@domain.hid> Date: Mon, 12 Mar 2007 11:01:28 +0100 (CET) From: "M. Koehrer" MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: [Xenomai-help] RTDM and user space hardware drivers List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: xenomai@xenomai.org Hi everybody, the RTDM API is really very good as API for drivers.=20 I have a real time (Xenomai) application in user space that has to access P= CI boards. The "classical" approach is now to use a kernel driver and to use RTDM as i= nterface between the user space application an the kernel space driver. However, for performance issues, I prefer to write a pure user mode driver. As the memory of the PCI board can be accesses from user space (using /dev/= mem)=20 I want to write a pure user space driver as this seems to me more efficien= t (and easier to debug) than a kernel driver. Also, only one application is accessing the driver at a time, I can link th= e driver directly to my application. My questions are now: 1. Is it possible to use the RTDM API also for pure user space drivers? 2. Is there any experience concerning the performance of a user space drive= r versus a kernel space driver? In my use case, I have to write and read about 60 byte (each direction) of = (block) data to/from the PCI I/O system. Thanks for any ideas or hints on that! Regards Mathias --=20 Mathias Koehrer mathias_koehrer@domain.hid Viel oder wenig? Schnell oder langsam? Unbegrenzt surfen + telefonieren ohne Zeit- und Volumenbegrenzung? DAS TOP ANGEBOT JETZT bei Arcor: g=FCnsti= g und schnell mit DSL - das All-Inclusive-Paket f=FCr clevere Doppel-Sparer, nur 39,85 =80 inkl. DSL- und ISDN-Grundgeb=FChr! http://www.arcor.de/rd/emf-dsl-2