On Sat, Mar 3, 2012 at 10:49 PM, Mariano Alvira <m...@devl.org> wrote: > On Sat, Mar 03, 2012 at 10:33:49PM +0400, Dmitry Eremin-Solenikov wrote: >> >> > >> > Most 802.15.4 transceivers in the market today provide a lot of >> > hardware acceleration, such as support for address filtering, auto >> > acknowledgement, CRC checking, retries and CSMA, etc. To use this kind >> > of features, the transceiver needs to 'know' its own short address, >> > MAC address, PAN ID etc. >> >> AFAIR the major part of that acceleration that can not be done in kernel >> space >> is sending ACK. > > The mc13224v can be in either promiscuous mode or autoack mode. In > order to do radio level acking, you must configure the address filters > (so linux would have to pass the pan, short, and long addrs to the > radio).
Yes, that is perfectly clear. AT86RF2xx chips have the same functionality. Either auto-ACK, or receive all packets. I don't remember if AT86 chips have possibility to ACK in promisc mode. > CCA/CSMA is another thing that probably can't be done in the kernel as > the timing is too tight. Initially we thought about implementing CCA/CSMA in kernel mode, then we actually checked the timing requirements and dropped ->cca() completely. AT86 chips can handle CSMA/CA in "MAC acceleration" mode. Freescale MC13xxx chips didn't have any MAC acceleration features at all (when I last checked them). I don't remember about other chips. Probably one can define several "profiles" required to support different features of standard. Implementing only parts of the next level won't bring additional features to the driver. * No features at all (mc13192-like). Optional hardware CRC (but highly recommended). Monitoring. SMAC (although SMAC requires CSMA/CA IIRC). * Support for simple MAC acceleration (at86rf2xx). CSMA/CA + ACK (which requires address filtering/matching). Recommended support for DATA REQUEST (as handled by at86 - single bit for all requests). Recommended transparent promisc mode - when setting promisc mode does not disable address matching. Recommended MAC-ACK (ACK with encryption) as per WirelessHART. Non-beaconed networks with full standard conformance. * Beacon tracking. Optional support for GTS & features from 802.15.4e. Client node in beaconed network with full standard conformance. * Beaconing - periodical beaconing support. Full network support as a PAN coordinator. -- With best wishes Dmitry ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Linux-zigbee-devel mailing list Linux-zigbee-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-zigbee-devel
