rtems-libbsd build error

Vijay Kumar Banerjee vijaykumar9597 at gmail.com
Wed Apr 17 18:40:45 UTC 2019


On Tue, Apr 16, 2019 at 4:24 PM Christian Mauderer <
christian.mauderer at embedded-brains.de> wrote:

> Am 16.04.19 um 11:28 schrieb Vijay Kumar Banerjee:
> >
> >
> >
> > On Fri, Apr 12, 2019 at 9:16 PM Christian Mauderer <list at c-mauderer.de
> > <mailto:list at c-mauderer.de>> wrote:
> >
> >     Am 12.04.19 um 16:26 schrieb Vijay Kumar Banerjee:
> >     >
> >     >
> >     > On Wed, Apr 10, 2019 at 12:50 PM Christian Mauderer
> >     > <christian.mauderer at embedded-brains.de
> >     <mailto:christian.mauderer at embedded-brains.de>
> >     > <mailto:christian.mauderer at embedded-brains.de
> >     <mailto:christian.mauderer at embedded-brains.de>>> wrote:
> >     >
> >     >     Am 09.04.19 um 18:12 schrieb Vijay Kumar Banerjee:
> >     >     > Hi,
> >     >     >
> >     >     > I have imported and ported the the drivers in 2 pairs(import
> >     and port)
> >     >     > of commits
> >     >     > for each one. Please have a look at this branch
> >     >     > https://github.com/thelunatic/rtems-libbsd/commits/tda19988
> >     >
> >     >     One detail: You have a commit named "tda19988.c: import from
> >     FreeBSD".
> >     >     Please remove the ".c".
> >     >
> >     > Noted.
> >     >
> >     >     Maybe it would be a good idea to split of the I2C part and put
> >     it in
> >     >     front of the other two parts. You can develop and test that
> >     independent
> >     >     with a test that just accesses some of the I2C devices on the
> >     board via
> >     >     the FreeBSD API and the translation driver discussed below.
> >     >
> >     > This is a good idea, I'll import iicbus separately and add the
> other
> >     > two on top of it.
> >     >
> >     >     >
> >     >     > I have also tried running the media01.exe and have seen it
> >     running
> >     >     fine
> >     >     > without
> >     >     > throwing any exceptions.
> >     >     >
> >     >     > I have used the fb.c and iicbus.c codes from the
> >     freebsd source. From
> >     >     > what I
> >     >     > understand, I think the next big steps would be to write an
> >     RTEMS
> >     >     > implementation layer for these portions of the code? And
> then a
> >     >     test in the
> >     >     > libbsd, like media01, to write to the /dev/fb0
> >     >     >
> >     >     > Can you please help me chalk out a rough outline of the next
> >     set of
> >     >     > actions? :)
> >     >
> >     >     As far as I can tell, there are two possible I2C buses here:
> >     >
> >     >     1. The one between the AM335x and the TDA19988.
> >     >
> >     >     2. The one directly on the HDMI connector (called HDMI_DSCL and
> >     >     HDMI_DSDA). I assume that's an I2C bus too.
> >     >
> >     >     For 1. the RTEMS driver should be used. You'll need some code
> that
> >     >     translates the FreeBSD API to the one used in RTEMS. Basically
> >     that will
> >     >     just be a FreeBSD-I2C-driver.
> >     >
> >     >     For 2: If that even is an independent I2C bus, you can use the
> >     driver
> >     >     provided by FreeBSD. I don't think that it is necessary to
> >     translate to
> >     >     the RTEMS API here.
> >     >
> >     > I had a look at the iic and iicbus codes in freebsd and the
> bbb-i2c.c
> >     > This looks very confusing to me. Are we looking for something like
> a
> >     > rtems-iicbus.c in the rtemsbsd that works like a wrapper to the
> >     bbb-i2c
> >     > code, and uses the freebsd api of DEVMETHODs?
> >
> >     Yes correct. Basically it would be necessary to have a I2C device
> driver
> >     for FreeBSD that translates to the RTEMS API.
> >
> >     >
> >     > I've not been able to figure out at one look, how to relate them
> and
> >     > get a wrapper like that. Any suggestions on how to approach this?
> >
> >     I haven't had a look at the FreeBSD drivers yet. The first part that
> I
> >     would have a look at is the description of the user facing FreeBSD
> API:
> >
> >
> https://www.freebsd.org/cgi/man.cgi?query=iic&apropos=0&sektion=0&manpath=FreeBSD+12.0-RELEASE+and+Ports&arch=default&format=html
> >
> >     Nice thing: They use a struct iic_msg that is compatible with Linux's
> >     struct i2c_msg (according to the man page). We are Linux compatible
> too.
> >     Can be a big advantage.
> >
> >     Then take a look at the simplest i2c driver that you can find in
> FreeBSD
> >     that uses the transfer API.
> >     freebsd-org/sys/dev/drm2/radeon/atombios_i2c.c looks good to me.
> >     Basically you have to implement the following functions (replace
> >     radeon_atom... by a useful prefix):
> >
> >     static device_method_t radeon_atom_hw_i2c_methods[] = {
> >             DEVMETHOD(device_probe,         radeon_atom_hw_i2c_probe),
> >             DEVMETHOD(device_attach,        radeon_atom_hw_i2c_attach),
> >             DEVMETHOD(device_detach,        radeon_atom_hw_i2c_detach),
> >             DEVMETHOD(iicbus_reset,         radeon_atom_hw_i2c_reset),
> >             DEVMETHOD(iicbus_transfer,      radeon_atom_hw_i2c_xfer),
> >             DEVMETHOD_END
> >     };
> >
> >     The iicbus_transfer function seems to get a struct iic_msg as a
> >     parameter. Now that's really lucky.
> >
> >     With that you should be able to open the i2c device in RTEMS and just
> >     pass the structure via the correct ioctl call to the RTEMS driver.
> >
> >     Basically you just have to pass the bus to use as a parameter to the
> >     driver. Take a look at some of the other drivers in nexus-devices.h
> that
> >     have for example an address as a parameter to see how you can do
> that.
> >
> > This gave a good idea of the objective. :)
> >
> > I had a look at the  bbb-i2c.c code and how it's registering
> > and setting up the i2c_bus struct with the transfer, set and destroy
> > fucntions.
> > I have a question from the fundamentals, the only function
> > of bbb-i2c.c
> > <https://git.rtems.org/rtems/tree/bsps/arm/beagle/i2c/bbb-i2c.c#n414>
> > that is 'accessible' with the header file is am335x_i2c_bus_register
> > which basically sets the i2c_bus struct
> > and calls the i2c_bus_register function from the dev/i2c.c .
> > To use the DEVMETHOD api, we need to be able to call the
> > transfer, destroy etc. functions of the bbb-i2c.c from the translation
> > layer in rtemsbsd. How do I #include the bbb-i2c.c in the new
> > translation driver that I'll write?
> >
> > Hope my question is stated clearly, please correct me if I'm getting
> > some fundamentals wrong.
>
> You are not fundamentally wrong but slightly off:
>
> Regarding the question how you access transfer, destroy, ... of the
> driver directly: Don't.
>
> You basically don't need to have a look at the bbb-i2c.c file of RTEMS
> for that driver. Where you should have a look is the Linux I2C API
> (which has been the model for the RTEMS API).
>
> Basically your drivers transfer function will do about the following:
>
> - Open "/dev/i2c0" (or some other path - that will be a parameter to the
> driver and has to be stored by probe or attach in some device structure).
>
> - Translate the "struct iic_msg" you get as an input to a "struct
> i2c_msg". Most likely that's just a cast.
>
> - Pass that via an ioctl call to the opened bus.
>
> - Check return value and translate to the matching return of FreeBSD.
>
> - Close "/dev/i2c0"
>
> Some of the open / close might could move to attach / detach. But that
> would be an optimization.
>
> That driver will work on any BSP that implements the current i2c API. So
> it's a generic translation layer.
>
> Best regards
>
> Christian
>
> Hi!

I started writing the driver layer implementation in the rtemsbsd, is this
going in the right
direction <
https://gist.github.com/thelunatic/2d8a2bf2cbead5bf82abe09000afea56> ?


> >
> >     >
> >     > Can we not totally use the iicbus in the freebsd source?
> >
> >     We already have a I2C driver for that BSP in RTEMS. If you would use
> the
> >     FreeBSD code, they would fight for the hardware. Of course it would
> be
> >     possible to replace the RTEMS driver by a FreeBSD one. But that would
> >     potentially break some applications. Besides that I think that a lot
> of
> >     RTEMS BSPs already have an I2C driver so a generic wrapper could be
> >     helpful for other BSPs too.
> >
> >     >
> >     >     >
> >     >     > Thanks
> >     >     >
> >     >     > On Tue, Apr 9, 2019 at 5:28 AM Chris Johns <chrisj at rtems.org
> >     <mailto:chrisj at rtems.org>
> >     >     <mailto:chrisj at rtems.org <mailto:chrisj at rtems.org>>
> >     >     > <mailto:chrisj at rtems.org <mailto:chrisj at rtems.org>
> >     <mailto:chrisj at rtems.org <mailto:chrisj at rtems.org>>>> wrote:
> >     >     >
> >     >     >     On 8/4/19 12:30 am, Vijay Kumar Banerjee wrote:
> >     >     >     > On Sun, Apr 7, 2019 at 6:24 PM Christian Mauderer
> >     >     >     <list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     > <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>> wrote:
> >     >     >     >     Am 07.04.19 um 14:50 schrieb Vijay Kumar Banerjee:
> >     >     >     >     > On Sun, Apr 7, 2019 at 6:08 PM Christian Mauderer
> >     >     >     <list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     >     <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>
> >     >     >     >     > <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>>> wrote:
> >     >     >     >     >     Am 07.04.19 um 14:35 schrieb Vijay Kumar
> >     Banerjee:
> >     >     >     >     >     > On Sun, Apr 7, 2019 at 5:37 PM Christian
> >     Mauderer
> >     >     >     >     >     <list at c-mauderer.de
> >     <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>
> >     >     >     >     <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>>
> >     >     >     >     >     > <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>
> >     >     >     >     <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
> >     <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
> >     >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>
> >     >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>
> >     <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>>>>> wrote:
> >     >     >     >     >     >     Am 07.04.19 um 13:08 schrieb Vijay
> Kumar
> >     >     Banerjee:
> >     >     >     >
> >     >     >     >     I don't think that there are a lot of docs for how
> >     to test.
> >     >     >     Although I'm
> >     >     >     >     sure that there are some scripts to run a number
> >     of libbsd
> >     >     >     tests, I'm
> >     >     >     >     not sure where. Maybe in the RTEMS tester but I
> think
> >     >     that is
> >     >     >     mainly for
> >     >     >     >     the core tests?
> >     >     >
> >     >     >     The documentation for testing can be found here ...
> >     >     >
> >     >     >
> >       https://docs.rtems.org/branches/master/user/testing/index.html
> >     >     >
> >     >     >     > so far I know, RTEMS Tester is only for core tests.
> >     >     >
> >     >     >     The `rtems-test` command checks the for test start and
> end
> >     >     banners.
> >     >     >     I am not
> >     >     >     sure if libbsd supports the test banners. Maybe it could
> >     now with
> >     >     >     Sebastian's
> >     >     >     movement of the test support code into libtest.
> >     >     >
> >     >     >     > I'll ask in the devel if there's some way to run
> >     libbsd test
> >     >     with
> >     >     >     the tester.
> >     >     >
> >     >     >     There is the `rtems-run` command which has similar args
> to
> >     >     >     `rtems-test`. It does
> >     >     >     suffer from a limitation I have not fixed which is stdin
> >     is not
> >     >     >     passed through
> >     >     >     to the console of the target. I also think the command
> has a
> >     >     timeout
> >     >     >     running,
> >     >     >     but I am not sure about this one.
> >     >     >
> >     >     >     Chris
> >     >     >
> >     >
> >     >     --
> >     >     --------------------------------------------
> >     >     embedded brains GmbH
> >     >     Herr Christian Mauderer
> >     >     Dornierstr. 4
> >     >     D-82178 Puchheim
> >     >     Germany
> >     >     email: christian.mauderer at embedded-brains.de
> >     <mailto:christian.mauderer at embedded-brains.de>
> >     >     <mailto:christian.mauderer at embedded-brains.de
> >     <mailto:christian.mauderer at embedded-brains.de>>
> >     >     Phone: +49-89-18 94 741 - 18
> >     >     Fax:   +49-89-18 94 741 - 08
> >     >     PGP: Public key available on request.
> >     >
> >     >     Diese Nachricht ist keine geschäftliche Mitteilung im Sinne
> >     des EHUG.
> >     >
> >
>
> --
> --------------------------------------------
> embedded brains GmbH
> Herr Christian Mauderer
> Dornierstr. 4
> D-82178 Puchheim
> Germany
> email: christian.mauderer at embedded-brains.de
> Phone: +49-89-18 94 741 - 18
> Fax:   +49-89-18 94 741 - 08
> PGP: Public key available on request.
>
> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
>
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