On Thu, Mar 31, 2016 at 11:55 PM, Ryan Stone <[email protected]> wrote:
> On Thu, Mar 31, 2016 at 4:39 PM, John Baldwin <[email protected]> wrote: > >> On Wednesday, March 30, 2016 11:20:51 AM Jim Harris wrote: >> > On Wed, Mar 30, 2016 at 10:47 AM, Luigi Rizzo <[email protected]> >> wrote: >> > >> > > Hi, >> > > I'd like to test the rate at which I can access device registers >> > > on a PCIe card, and was wondering whether I need to patch a device >> > > driver, or perhaps I can use /dev/kmem once I figure out where >> > > the registers are mapped ? >> > > >> > >> > You do not need to patch a device driver. Have you looked at >> > libpciaccess? This should give you everything you need. >> >> You can also look at what pciconf uses. (It has a read_config() method >> that uses an ioctl on an fd of /dev/pci). >> > > pciconf can only access the configuration space, right? I believe that > Luigi is more interested in measuring the latency to a register mapped from > a BAR. > Thank you all for you answers, I will look at libpciaccess. Yes my goal is to look at the rate and latency for accessing BAR-mapped registers cheers luigi -- -----------------------------------------+------------------------------- Prof. Luigi RIZZO, [email protected] . Dip. di Ing. dell'Informazione http://www.iet.unipi.it/~luigi/ . Universita` di Pisa TEL +39-050-2217533 . via Diotisalvi 2 Mobile +39-338-6809875 . 56122 PISA (Italy) -----------------------------------------+------------------------------- _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "[email protected]"
