No uart output on my snowball board

No uart output on my snowball board

[Steven Rostedt]

I decided to play with my snowball board as that's the easiest arm
board I have to do testing on, and it was reported to me that I broke
function graph tracing on the arm boards. But I haven't booted my
snowball since 3.8. When I tried with the latest kernel, it didn't give
me *any* output. I figured something was up with the uart, but the
board also didn't boot.

I did a bisect to find out where the uart stopped working (I also
stumbled on where the board stopped booting, but still need to find
that commit). The uart died with this commit:

commit a0998b8321eb5f53ef51924f5ab6c69237ac1025
Author: Lee Jones <lee.jones@linaro.org>
Date:   Thu Aug 22 16:18:56 2013 +0100

    ARM: ux500: Remove UART support when booting without Device Tree
    
    It's time to remove all ATAG support from ux500 and rely solely on
    Device Tree booting. This patch is part of that endeavour.
    
    Signed-off-by: Lee Jones <lee.jones@linaro.org>
    Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This happened between 3.12 and 3.13.

Does this mean that I need to get device tree support for this. I have
no idea how to fix it as a device tree to me is a christmas tree (a
tree with little lighty devices on it). Thus I'll just go and throw
this out at you.

Thanks,

-- Steve

No uart output on my snowball board

[Lee Jones]

> I decided to play with my snowball board as that's the easiest arm
> board I have to do testing on, and it was reported to me that I broke
> function graph tracing on the arm boards. But I haven't booted my
> snowball since 3.8. When I tried with the latest kernel, it didn't give
> me *any* output. I figured something was up with the uart, but the
> board also didn't boot.
> 
> I did a bisect to find out where the uart stopped working (I also
> stumbled on where the board stopped booting, but still need to find
> that commit). The uart died with this commit:
> 
> commit a0998b8321eb5f53ef51924f5ab6c69237ac1025
> Author: Lee Jones <lee.jones@linaro.org>
> Date:   Thu Aug 22 16:18:56 2013 +0100
> 
>     ARM: ux500: Remove UART support when booting without Device Tree
>     
>     It's time to remove all ATAG support from ux500 and rely solely on
>     Device Tree booting. This patch is part of that endeavour.
>     
>     Signed-off-by: Lee Jones <lee.jones@linaro.org>
>     Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> 
> This happened between 3.12 and 3.13.
> 
> Does this mean that I need to get device tree support for this. I have
> no idea how to fix it as a device tree to me is a christmas tree (a
> tree with little lighty devices on it). Thus I'll just go and throw
> this out at you.

This is a very slimmed down of my Makefile.  It should bootstrap you
with what you need.  If there are any issues with that that you can't
fix, ping me and I'll test it as-is.  Bear in mind that some of these
config options are probably deprecated by now.  If there are any holes
I'm sure LinusW will spot them.

CROSS_COMPILE	?= arm-linux-gnueabi-
build_dir       := $(CURDIR)/build-snowball
config_file     := $(build_dir)/.config
devicetree	:= $(build_dir)/arch/arm/boot/dts/ste-snowball.dtb
defconfig	:= u8500_defconfig
cpus		:= 4

make_options := -f Makefile \
                ARCH=arm \
                CROSS_COMPILE=$(CROSS_COMPILE) \
                KBUILD_OUTPUT=$(build_dir)

config-devicetree: config-base FORCE
	# Configure in the optional device tree if available
	@if [ -r $(devicetree) ] ; then \
	$(CURDIR)/scripts/config --file $(config_file) \
	  --enable USE_OF \
	  --enable ARM_APPENDED_DTB \
	  --enable ARM_ATAG_DTB_COMPAT \
	  --enable PROC_DEVICETREE \
	  --set-str ARM_APPENDED_DTB_FILE $(devicetree) ; \
	else \
	  echo "$(devicetree) not found, or not readable" ; \
	fi

build: config-devicetree FORCE
	@mkdir -p $(build_dir)
	$(MAKE) $(make_options) dtbs
	$(MAKE) $(make_options) $(defconfig)
	$(MAKE) $(make_options) -j $(cpus) zImage
	cat $(devicetree) >> $(build_dir)/arch/arm/boot/zImage

	mkimage -A arm -O linux -T kernel -C none \
	-a 0x00008000 -e 0x00008000 -n "Linux" 	  \
	-d $(build_dir)/arch/arm/boot/zImage	  \
	$(build_dir)/uImage

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

No uart output on my snowball board

[Linus Walleij]

On Fri, Jul 11, 2014 at 4:30 AM, Steven Rostedt <rostedt@goodmis.org> wrote:

> commit a0998b8321eb5f53ef51924f5ab6c69237ac1025
> Author: Lee Jones <lee.jones@linaro.org>
> Date:   Thu Aug 22 16:18:56 2013 +0100
>
>     ARM: ux500: Remove UART support when booting without Device Tree
>
>     It's time to remove all ATAG support from ux500 and rely solely on
>     Device Tree booting. This patch is part of that endeavour.
>
>     Signed-off-by: Lee Jones <lee.jones@linaro.org>
>     Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

I hate that I didn't spot the speling mistake in the subject,
its ATAG support we're removing, not UART :-)

Anyway, I think you got enough hints on how we do this
with appended devicetrees instead, Lee's snippet should
work or check out this page that I also posted to your
G+ post:
http://www.df.lth.se/~triad/krad/ux00/

Yours,
Linus Walleij

No uart output on my snowball board

[Steven Rostedt]

On Fri, 11 Jul 2014 14:00:55 +0200
Linus Walleij <linus.walleij@linaro.org> wrote:

> On Fri, Jul 11, 2014 at 4:30 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> > commit a0998b8321eb5f53ef51924f5ab6c69237ac1025
> > Author: Lee Jones <lee.jones@linaro.org>
> > Date:   Thu Aug 22 16:18:56 2013 +0100
> >
> >     ARM: ux500: Remove UART support when booting without Device Tree
> >
> >     It's time to remove all ATAG support from ux500 and rely solely on
> >     Device Tree booting. This patch is part of that endeavour.
> >
> >     Signed-off-by: Lee Jones <lee.jones@linaro.org>
> >     Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> 
> I hate that I didn't spot the speling mistake in the subject,
> its ATAG support we're removing, not UART :-)
> 
> Anyway, I think you got enough hints on how we do this
> with appended devicetrees instead, Lee's snippet should
> work or check out this page that I also posted to your
> G+ post:
> http://www.df.lth.se/~triad/krad/ux00/
> 

Thanks, with everyone's feedback I got it working with ktest.

I added the following to my ktest snowball.conf:

OUTPUT_BOOT := ${OUTPUT_DIR}/arch/arm/boot

PRE_BUILD = ${MAKE_CMD} O=${OUTPUT_DIR} dtbs
POST_BUILD = cat ${OUTPUT_BOOT}/zImage ${OUTPUT_BOOT}/dts/ste-snowball.dtb > ${OUTPUT_BOOT}/zImage.snowball; mkimage -A arm -O linux -C none -T kernel -a 0x00008000 -e 0x00008000 -d ${OUTPUT_BOOT}/zImage.snowball ${OUTPUT_BOOT}/uImage.snowball

and walla!

root at linaro-ubuntu-desktop:~# uname -r
3.16.0-rc4-test-00042-g4f440cd


Thanks everyone!

-- Steve

No uart output on my snowball board

[Lee Jones]

On Fri, 11 Jul 2014, Steven Rostedt wrote:

> On Fri, 11 Jul 2014 14:00:55 +0200
> Linus Walleij <linus.walleij@linaro.org> wrote:
> 
> > On Fri, Jul 11, 2014 at 4:30 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> > 
> > > commit a0998b8321eb5f53ef51924f5ab6c69237ac1025
> > > Author: Lee Jones <lee.jones@linaro.org>
> > > Date:   Thu Aug 22 16:18:56 2013 +0100
> > >
> > >     ARM: ux500: Remove UART support when booting without Device Tree
> > >
> > >     It's time to remove all ATAG support from ux500 and rely solely on
> > >     Device Tree booting. This patch is part of that endeavour.
> > >
> > >     Signed-off-by: Lee Jones <lee.jones@linaro.org>
> > >     Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> > 
> > I hate that I didn't spot the speling mistake in the subject,
> > its ATAG support we're removing, not UART :-)
> > 
> > Anyway, I think you got enough hints on how we do this
> > with appended devicetrees instead, Lee's snippet should
> > work or check out this page that I also posted to your
> > G+ post:
> > http://www.df.lth.se/~triad/krad/ux00/
> > 
> 
> Thanks, with everyone's feedback I got it working with ktest.
> 
> I added the following to my ktest snowball.conf:
> 
> OUTPUT_BOOT := ${OUTPUT_DIR}/arch/arm/boot
> 
> PRE_BUILD = ${MAKE_CMD} O=${OUTPUT_DIR} dtbs
> POST_BUILD = cat ${OUTPUT_BOOT}/zImage ${OUTPUT_BOOT}/dts/ste-snowball.dtb > ${OUTPUT_BOOT}/zImage.snowball; mkimage -A arm -O linux -C none -T kernel -a 0x00008000 -e 0x00008000 -d ${OUTPUT_BOOT}/zImage.snowball ${OUTPUT_BOOT}/uImage.snowball
> 
> and walla!
> 
> root at linaro-ubuntu-desktop:~# uname -r
> 3.16.0-rc4-test-00042-g4f440cd

Good work.  Glad to be of service.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

No uart output on my snowball board

[Lee Jones]

On Fri, 11 Jul 2014, Linus Walleij wrote:
> On Fri, Jul 11, 2014 at 4:30 AM, Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> > commit a0998b8321eb5f53ef51924f5ab6c69237ac1025
> > Author: Lee Jones <lee.jones@linaro.org>
> > Date:   Thu Aug 22 16:18:56 2013 +0100
> >
> >     ARM: ux500: Remove UART support when booting without Device Tree
> >
> >     It's time to remove all ATAG support from ux500 and rely solely on
> >     Device Tree booting. This patch is part of that endeavour.
> >
> >     Signed-off-by: Lee Jones <lee.jones@linaro.org>
> >     Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> 
> I hate that I didn't spot the speling mistake in the subject,
> its ATAG support we're removing, not UART :-)

Now you're going coo-coo. :)

The subject line is fine.  Take a look at the patch.

> Anyway, I think you got enough hints on how we do this
> with appended devicetrees instead, Lee's snippet should
> work or check out this page that I also posted to your
> G+ post:
> http://www.df.lth.se/~triad/krad/ux00/

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog