A FreeBSD driver for some DekTec ASI boards (DTA-140, DTA-145, DTA-2145). It is compatible with FreeBSD 7.x, 8.x, 9.x and possibly 10.x (untested).
- dektec.c - the actual device driver code
- dektec.h - lots of IOCTL codes used in the driver
- Dta1xxCodes.h - codes and constants from DekTec
- Dta1xxRegs.h - use to include GenRegs.h, RxRegs.h and TxRegs.h.
- GenRegs.h - definitions related to the generic control register, from DekTec, adapted to FreeBSD
- RxRegs.h - definitions related to the RX control register, from DekTec, adapted to FreeBSD
- TxRegs.h - definitions related to the TX control register, from DekTec, adapted to FreeBSD
- Plx905x.h - constants for the PLX 905x PCI controller chip (9056 in our case).
Pretty much everything happens in dektec.c. The driver is not compatible with DekTec's DTAPI but it supports a read/write interface with polling.
To understand what is going on you will need at least some of the following:
A PCI 9056BA Data Book, for everything related to DMA. Newer boards use an FPGA with the same interface.
A copy of the original busdma paper: A Machine-Independent DMA Framework for NetBSD. Especially check bus_dmamap_sync.
Boards register maps from DekTec, or the Linux driver source code, to check the value of register base addresses, etc.
The DTA-140 data sheet, DVB/ASI Input+Output Adapter for PCI Bus, which will provide a broad description of the DTA-140 operations.
A copy of ISO/IEC 13818 Part 1 could help when developing userland software.
If you are using DVB, the relevant ETSI standards that you can grab at www.etsi.org.
To actually try things out:
An ASI source and/or ASI analyzer to handle actual streams.
A valid MPEG2 transport stream to test the output functions. You can make one with ffmpeg or grab it from a TV decoder that supports TS recording.
How to install
make install from the project directory:
# make install install -o root -g wheel -m 555 dektec.ko /boot/kernel kldxref /boot/kernel #
To clean up after building:
# make clean cleandepend
Remember to do this when you switch architecture while using the same source tree (i.e. when building from i386 and amd64 boxes over a NFS share).
To load or unload the locally compiled driver:
# make load
# make unload
To load or unload the installed driver:
# kldload dektec
# kldunload dektec
To uninstall the driver:
# rm -f /boot/kernel/dektec.ko # kldxref /boot/kernel
To load at every boot, add
dektec_load="YES" to your
You might also create a package to be used with
Be sure to use matching FreeBSD versions when deploying binaries.
Bugs / gotchas
None if you use it correctly :) uptimes of years have been observed in production (v1.0.0), but the range of operations performed by the client software is quite narrow so you'd better test everything carefully in your environment.
Only 188-byte packet are supported.
Lots of boards are missing, but I can only support the models that I am actually using. The DTA-140 could be probably considered legacy and you will not be able to order it anymore. Lots of code is related to the handling of this board, which was the first to be implemented.
SDI operations are not supported.
USB devices are not supported (not sure how much work it could be).
You might have noticed that there's no documentation.
Lots of constants may be unused, but you'd better keep them for future use.
- v1.0.0: Initial import from production code
- v1.1.0: General cleanup
- v1.2.1: Locking improvements
- v1.2.2: Fixed call to bus_dmamap_load (BUS_DMA_NOWAIT).
Cleanup dumb assumptions in
Carefully review the dmamap callbacks for edge cases.
Split the TX and RX channels into multiple devices. Then we should be able to add support for input- and output-only boards with multiple channels.
Let userland software configure the programmable input/output channel on the DTA-145. Right now it is hardcoded as input.
Add a few sysctl values to set the default parameters. This could be used to make streams accessible to shell scripts / pipes and to use netcat or ssh as a transport.
Add support for 208-byte packets.
Do something useful with the led, possibly from userland.
Do something interesting with DTrace.