[U-Boot] ARM CONFIG_OF_CONTROL status

[Simon Glass <sjg@chromium.org>]

Hi,

On Sun, Jul 1, 2012 at 10:43 PM, Michal Simek <monstr@monstr.eu> wrote:

> 2012/6/29 Stephan Linz <linz@li-pro.net>:
> > Am Freitag, den 29.06.2012, 10:18 +0200 schrieb Michal Simek:
> >> On 06/29/2012 04:32 AM, Simon Glass wrote:
> >> > Hi,
> >> >
> >> > --snip--
> >>
> >> I have sent support for Microblaze. Currently without dts because I
> want to clear this part a little bit.
> >
> > Hi Michal,
> >
> > looks good, I've been waiting a long time on the FDT support in U-Boot
> > for Microblaze -- great -- PS: see my comment on patch 5 ...
> >
> >>
> >> Tegra is using ./arch/arm/dts/tegra20.dtsi and
> board/nvidia/dts/tegra2-seaboard.dts
> >> and they are composed together in dts/Makefile by calling preprocessor.
> >> Microblaze will be totally different case because every Microblaze hw
> design is different.
> >
> > Yes, that's right. We will never be in the position to define a skeleton
> > or a basic platform configuration.
> >
> >> We can use two main buses (little and big endian) and cpu is also
> configurable.
> >> Based on this for Microblaze is the best solution directly to use dts.
> >> (DTS for Microblaze is also generated directly from design tool).
> >
> > ... directly in the context of a board, not arch/cpu, right?
>
> yes.
>
> >
> >>
> >>
> >> Anyway - here is the bug message I am getting if I use full dts in
> board/<name>/dts/microblaze.dts
> >> and empty arch/microblaze/dts/microblaze.dtsi
> >>
> >> <stdin>:34:3: error: invalid preprocessing directive #address
> >> <stdin>:35:3: error: invalid preprocessing directive #size
> >> <stdin>:52:4: error: invalid preprocessing directive #address
> >> <stdin>:53:4: error: invalid preprocessing directive #cpus
> >> <stdin>:54:4: error: invalid preprocessing directive #size
> >> <stdin>:155:4: error: invalid preprocessing directive #address
> >> <stdin>:156:4: error: invalid preprocessing directive #size
> >> <stdin>:160:5: error: invalid preprocessing directive #gpio
> >> <stdin>:192:5: error: invalid preprocessing directive #gpio
> >> <stdin>:209:5: error: invalid preprocessing directive #gpio
> >> <stdin>:241:5: error: invalid preprocessing directive #gpio
> >> <stdin>:267:5: error: invalid preprocessing directive #address
> >> <stdin>:268:5: error: invalid preprocessing directive #size
> >> <stdin>:394:5: error: invalid preprocessing directive #interrupt
> >>
> >> This is error for opposite case - empty microblaze.dts and full
> microblaze.dtsi.
> >
> > That are CPP errors, because the auto generated xilinx.dts is full of
> > CPP pragma like syntax (#something) that are wrong (invalid).
>
> I know what it is.
>
> >
> >>
> >> make[1]: Entering directory `/mnt/projects/u-boot/dts'
> >> rc=$( cat /mnt/projects/u-boot/board/petalogix/dts/microblaze.dts |
> microblaze-unknown-linux-gnu-gcc -E
> >> -P
> -DARCH_CPU_DTS=\"/mnt/projects/u-boot/arch/microblaze/dts/microblaze.dtsi\"
> - | { { dtc -R 4 -p 0x1000
> >> -O dtb -o dt.dtb - 2>&1 ; echo $? >&3 ; } | grep -v '^DTC: dts->dtb  on
> file' ; } 3>&1 ) ; \
> >>       exit $rc
> >> /bin/sh: line 1: exit: too many arguments
> >> make[1]: *** [dt.dtb] Error 1
> >> make[1]: Leaving directory `/mnt/projects/u-boot/dts'
> >>
> >>
> >> I have just tried to fix it by introducing new CONFIG option for
> skipping that preprocessor
> >> part.
> >
> > Instead of disable / skipp the CPP step you can hide the auto generated
> > xilinx.dts with a second include stage, for example:
> >
> > board/microblaze/dts/microblaze.dts looks like:
> >
> > /include/ ARCH_CPU_DTS
> > /include/ BOARD_DTS
> >
> >
> > Right, only two lines.   The arch/microblaze/dts/microblaze.dtsi remains
> > empty as you have said above. Just new is BOARD_DTS -- with the attached
> > patch for dts/Makefile you can copy the auto generated xilinx.dts into
> > the specific board directory and the CPP step substitute the right place
> > to board/microblaze/microblaze-generic/dts/microblaze.dts
> >
> > I think there are no side effects with other ports like the tegra2.
> >
> > If you want you can omit the ARCH_CPU_DTS inclusion. The architectural
> > microblaze.dtsi file is empty and (!!) have to be empty, because the DTC
> > will break with an error on multiple "/dts-v1/;" lines!
> >
> > Here is the patch:
> >
> > diff --git a/dts/Makefile b/dts/Makefile
> > index 914e479..b1f47a1 100644
> > --- a/dts/Makefile
> > +++ b/dts/Makefile
> > @@ -36,7 +36,8 @@ $(error Your architecture does not have device tree
> > support enabled. \
> > Please define CONFIG_ARCH_DEVICE_TREE))
> >
> > # We preprocess the device tree file provide a useful define
> > -DTS_CPPFLAGS := -DARCH_CPU_DTS=
> > \"$(SRCTREE)/arch/$(ARCH)/dts/$(CONFIG_ARCH_DEVICE_TREE).dtsi\"
> > +DTS_CPPFLAGS := -DARCH_CPU_DTS=
> > \"$(SRCTREE)/arch/$(ARCH)/dts/$(CONFIG_ARCH_DEVICE_TREE).dtsi\" \
> > +               -DBOARD_DTS=
> > \"$(SRCTREE)/board/$(VENDOR)/$(BOARD)/dts/$(DEVICE_TREE).dts\"
> >
> > all:   $(obj).depend $(LIB)
>
> Not sure if using another dts file will be the best approach.
> From my point of view will be the best to support only one dts file
> (without dtsi)
> because it is much cleaner then using 3 dts files.
>

Well there is no inherent problem with having multiple include files,
except that it is hard to support with the old dtc when there are in
different subdirs.

As a workaround, how about putting the include files in the
board/vendor/dts subdir as well for now?

Regards,
Simon


>
> Thanks,
> Michal
>