> -----Mensaje original----- > De: Wolfgang Grandegger [mailto:[email protected]] > Enviado el: Monday, March 14, 2011 2:51 PM > Para: Jorge Fernandez Monteagudo > CC: [email protected] > Asunto: Re: [Socketcan-users] Setting the clock, ocr and cdr values > > On 03/14/2011 02:37 PM, Jorge Fernandez Monteagudo wrote: > >> -----Mensaje original----- > >> De: Wolfgang Grandegger [mailto:[email protected]] > >> Enviado el: Monday, March 14, 2011 1:06 PM > >> Para: Jorge Fernandez Monteagudo > >> CC: [email protected] > >> Asunto: Re: [Socketcan-users] Setting the clock, ocr and cdr values > >> > >> On 03/14/2011 11:42 AM, Jorge Fernandez Monteagudo wrote: > >>> Hi, > >>> > >>> I'm trying to implement my can infrastructure with socketcan. I > would > >> like to know where to find > >>> information about the values from sja1000_priv struct, the > >> can.clock.freq, ocr and cdr. > >> > >> Not sure what you are looking for. The meaning of theses values is > >> described in the SJA1000 datasheet. > >> > > > > Well, I'm trying to setup the sja1000 chip using the socketcan > architecture. > > In my old code I had the registers CDR, BTR0, BTR1, OCR, CMR and IER > > loaded with some values in order to set the pelican mode with 1Mbps > > and let the chip ready to serve interruptions. Now I'm trying to > replicate > > this in a modified version of the plx_pci.c but I've seen that the > only > > register used are from the sja1000_priv struct. > > You need to provide proper cdr, ocr and the CAN clock sources > frequency. > See also: > > http://lxr.linux.no/#linux+v2.6.37.3/drivers/net/can/sja1000/sja1000.c# > L242 > > The rest is handled by the SJA1000 driver. >
Oh yes, I see where this sja1000_priv struct fields are used! >From the 'static int sja1000_set_bittiming(struct net_device *dev)' method there is some way to set manually the btr0 and btr1 values? In my code I set BTR0 <- 0x01 BTR1 <- 0x10 to set the 1000 Kbs. > >>> I'm following the plx_pci.c code but in my driver I setup these > >> register in a different way. > >>> First, I set the CDR <- 0xC0, then I set the clock using the BTR0 > and > >> BTR1 registers to set the 1Mbps > >>> baudrate, BTR0 <- 0x01, BTR1 <- 0x10 and finally the OCR register > is > >> initialized with OCR <- 0x1A. > >> > >> The input clock frequency, cdr and ocr must be defined by the > SJA1000 > >> driver, e.g.: > >> > >> > http://lxr.linux.no/#linux+v2.6.37.3/drivers/net/can/sja1000/plx_pci.c# > >> L526 > >> > >> Some drivers allow to set these values via module parameter. So, > >> depending on the driver appropriate for your CAN hardware, you need > to > >> adjust them. The bit-timing have to be defined via netlink interface > as > >> described here: > >> > >> > http://lxr.linux.no/#linux+v2.6.37.3/Documentation/networking/can.txt#L > >> 635 > >> > > > > Thanks for the info, now I get an error in dmesg: "bit-timing not yet > defined" > > then I suppose I'll need to follow this last link. > > Yes, you need to set the bit-timing before you can start the device. > Where I can found the iproute2 utility suite? I have debian 5.0.7, but the command # ip link set can0 type can help don't print any bitrate or tq option... # ip -V ip utility, iproute2-ss080725 > > > >> What CAN hardware are you using? > >> > > > > It's a SJA1000 can controller embedded inside a FPGA implementing a > PCI bus > > controller, then I need to set up the CAN address window before > accessing the > > CAN and I'm following the plx_pci.c code. > > OK, now I remember. > > Wolfgang. Thanks, Jorge Este mensaje se dirige exclusivamente a su destinatario y puede contener información privilegiada o CONFIDENCIAL. Si no es vd. el destinatario indicado, queda notificado de que la utilización, divulgación y/o copia sin autorización está prohibida en virtud de la legislación vigente. Si ha recibido este mensaje por error, le rogamos que nos lo comunique inmediatamente por esta misma vía y proceda a su destrucción. This message is intended exclusively for its addressee and may contain information that is CONFIDENTIAL and protected by professional privilege. If you are not the intended recipient you are hereby notified that any dissemination, copy or disclosure of this communication is strictly prohibited by law. If this message has been received in error, please immediately notify us via e-mail and delete it. _______________________________________________ Socketcan-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/socketcan-users
