[PATCH v2] u-boot-tools: Add dependency on libyaml for dtschema validation

[PATCH v2] u-boot-tools: Add dependency on libyaml for dtschema validation

[Khem Raj]

yamltree host tool, used to emit YAML from the DT, is now
built as part of the normal u-boot-tools build to support
the schema infrastructure

Fixes link errors like

| /usr/bin/ld: scripts/dtc/yamltree.o: in function `dt_to_yaml':
| yamltree.c:(.text+0x91b): undefined reference to `yaml_emitter_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x926): undefined reference to `yaml_emitter_set_output_file'
| /usr/bin/ld: yamltree.c:(.text+0x933): undefined reference to `yaml_stream_start_event_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x93e): undefined reference to `yaml_emitter_emit'
| /usr/bin/ld: yamltree.c:(.text+0x957): undefined reference to `yaml_document_start_event_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x962): undefined reference to `yaml_emitter_emit'
| /usr/bin/ld: yamltree.c:(.text+0x983): undefined reference to `yaml_sequence_start_event_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x98e): undefined reference to `yaml_emitter_emit'
| /usr/bin/ld: yamltree.c:(.text+0x9ab): undefined reference to `yaml_sequence_end_event_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x9b6): undefined reference to `yaml_emitter_emit'
| /usr/bin/ld: yamltree.c:(.text+0x9c8): undefined reference to `yaml_document_end_event_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x9d3): undefined reference to `yaml_emitter_emit'
| /usr/bin/ld: yamltree.c:(.text+0x9e3): undefined reference to `yaml_stream_end_event_initialize'
| /usr/bin/ld: yamltree.c:(.text+0x9ee): undefined reference to `yaml_emitter_emit'
| /usr/bin/ld: yamltree.c:(.text+0x9fa): undefined reference to `yaml_emitter_delete'

Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>
---
v2: Add dep on native libyalm alone

 meta/recipes-bsp/u-boot/u-boot-tools.inc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/meta/recipes-bsp/u-boot/u-boot-tools.inc b/meta/recipes-bsp/u-boot/u-boot-tools.inc
index 4e4f7fa092..a055409c2c 100644
--- a/meta/recipes-bsp/u-boot/u-boot-tools.inc
+++ b/meta/recipes-bsp/u-boot/u-boot-tools.inc
@@ -1,5 +1,5 @@
 SUMMARY = "U-Boot bootloader tools"
-DEPENDS += "gnutls openssl util-linux swig-native"
+DEPENDS += "gnutls openssl util-linux swig-native libyaml-native"

 inherit python3native
 export STAGING_INCDIR = "${STAGING_INCDIR_NATIVE}"

Re: [OE-core] [PATCH v2] u-boot-tools: Add dependency on libyaml for dtschema validation

[Ross Burton]

Is this specific to the 2026.04 upgrade or does it apply to 2026.01 too?

Ross

> On 12 Apr 2026, at 04:57, Khem Raj via lists.openembedded.org <raj.khem=gmail.com@lists.openembedded.org> wrote:
> 
> yamltree host tool, used to emit YAML from the DT, is now
> built as part of the normal u-boot-tools build to support
> the schema infrastructure
> 
> Fixes link errors like
> 
> | /usr/bin/ld: scripts/dtc/yamltree.o: in function `dt_to_yaml':
> | yamltree.c:(.text+0x91b): undefined reference to `yaml_emitter_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x926): undefined reference to `yaml_emitter_set_output_file'
> | /usr/bin/ld: yamltree.c:(.text+0x933): undefined reference to `yaml_stream_start_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x93e): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x957): undefined reference to `yaml_document_start_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x962): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x983): undefined reference to `yaml_sequence_start_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x98e): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9ab): undefined reference to `yaml_sequence_end_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x9b6): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9c8): undefined reference to `yaml_document_end_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x9d3): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9e3): undefined reference to `yaml_stream_end_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x9ee): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9fa): undefined reference to `yaml_emitter_delete'
> 
> Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>
> ---
> v2: Add dep on native libyalm alone
> 
> meta/recipes-bsp/u-boot/u-boot-tools.inc | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/meta/recipes-bsp/u-boot/u-boot-tools.inc b/meta/recipes-bsp/u-boot/u-boot-tools.inc
> index 4e4f7fa092..a055409c2c 100644
> --- a/meta/recipes-bsp/u-boot/u-boot-tools.inc
> +++ b/meta/recipes-bsp/u-boot/u-boot-tools.inc
> @@ -1,5 +1,5 @@
> SUMMARY = "U-Boot bootloader tools"
> -DEPENDS += "gnutls openssl util-linux swig-native"
> +DEPENDS += "gnutls openssl util-linux swig-native libyaml-native"
> 
> inherit python3native
> export STAGING_INCDIR = "${STAGING_INCDIR_NATIVE}"
> 
> -=-=-=-=-=-=-=-=-=-=-=-
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> View/Reply Online (#235052): https://lists.openembedded.org/g/openembedded-core/message/235052
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Re: [OE-core] [PATCH v2] u-boot-tools: Add dependency on libyaml for dtschema validation

[Khem Raj]

[-- Attachment #1: Type: text/plain, Size: 3323 bytes --]

On Wed, Apr 15, 2026 at 8:33 AM Ross Burton <Ross.Burton@arm.com> wrote:

> Is this specific to the 2026.04 upgrade or does it apply to 2026.01 too?
>

I think 2026.01 does not need it.


>
> Ross
>
> > On 12 Apr 2026, at 04:57, Khem Raj via lists.openembedded.org <raj.khem=
> gmail.com@lists.openembedded.org> wrote:
> >
> > yamltree host tool, used to emit YAML from the DT, is now
> > built as part of the normal u-boot-tools build to support
> > the schema infrastructure
> >
> > Fixes link errors like
> >
> > | /usr/bin/ld: scripts/dtc/yamltree.o: in function `dt_to_yaml':
> > | yamltree.c:(.text+0x91b): undefined reference to
> `yaml_emitter_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x926): undefined reference to
> `yaml_emitter_set_output_file'
> > | /usr/bin/ld: yamltree.c:(.text+0x933): undefined reference to
> `yaml_stream_start_event_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x93e): undefined reference to
> `yaml_emitter_emit'
> > | /usr/bin/ld: yamltree.c:(.text+0x957): undefined reference to
> `yaml_document_start_event_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x962): undefined reference to
> `yaml_emitter_emit'
> > | /usr/bin/ld: yamltree.c:(.text+0x983): undefined reference to
> `yaml_sequence_start_event_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x98e): undefined reference to
> `yaml_emitter_emit'
> > | /usr/bin/ld: yamltree.c:(.text+0x9ab): undefined reference to
> `yaml_sequence_end_event_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x9b6): undefined reference to
> `yaml_emitter_emit'
> > | /usr/bin/ld: yamltree.c:(.text+0x9c8): undefined reference to
> `yaml_document_end_event_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x9d3): undefined reference to
> `yaml_emitter_emit'
> > | /usr/bin/ld: yamltree.c:(.text+0x9e3): undefined reference to
> `yaml_stream_end_event_initialize'
> > | /usr/bin/ld: yamltree.c:(.text+0x9ee): undefined reference to
> `yaml_emitter_emit'
> > | /usr/bin/ld: yamltree.c:(.text+0x9fa): undefined reference to
> `yaml_emitter_delete'
> >
> > Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>
> > ---
> > v2: Add dep on native libyalm alone
> >
> > meta/recipes-bsp/u-boot/u-boot-tools.inc | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/meta/recipes-bsp/u-boot/u-boot-tools.inc
> b/meta/recipes-bsp/u-boot/u-boot-tools.inc
> > index 4e4f7fa092..a055409c2c 100644
> > --- a/meta/recipes-bsp/u-boot/u-boot-tools.inc
> > +++ b/meta/recipes-bsp/u-boot/u-boot-tools.inc
> > @@ -1,5 +1,5 @@
> > SUMMARY = "U-Boot bootloader tools"
> > -DEPENDS += "gnutls openssl util-linux swig-native"
> > +DEPENDS += "gnutls openssl util-linux swig-native libyaml-native"
> >
> > inherit python3native
> > export STAGING_INCDIR = "${STAGING_INCDIR_NATIVE}"
> >
> > -=-=-=-=-=-=-=-=-=-=-=-
> > Links: You receive all messages sent to this group.
> > View/Reply Online (#235052):
> https://lists.openembedded.org/g/openembedded-core/message/235052
> > Mute This Topic: https://lists.openembedded.org/mt/118784443/6875888
> > Group Owner: openembedded-core+owner@lists.openembedded.org
> > Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub [
> ross.burton@arm.com]
> > -=-=-=-=-=-=-=-=-=-=-=-
> >
>
>

[-- Attachment #2: Type: text/html, Size: 4816 bytes --]

Re: [OE-core] [PATCH v2] u-boot-tools: Add dependency on libyaml for dtschema validation

[Quentin Schulz]

Hi Ross,

On 4/15/26 5:32 PM, Ross Burton via lists.openembedded.org wrote:
> Is this specific to the 2026.04 upgrade or does it apply to 2026.01 too?
> 

The file only exists in 2026.04+.

Cheers,
Quentin

Re: [OE-core] [PATCH v2] u-boot-tools: Add dependency on libyaml for dtschema validation

[Quentin Schulz]

Hi Khem,

On 4/12/26 5:57 AM, Khem Raj via lists.openembedded.org wrote:
> yamltree host tool, used to emit YAML from the DT, is now
> built as part of the normal u-boot-tools build to support
> the schema infrastructure
> 
> Fixes link errors like
> 
> | /usr/bin/ld: scripts/dtc/yamltree.o: in function `dt_to_yaml':
> | yamltree.c:(.text+0x91b): undefined reference to `yaml_emitter_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x926): undefined reference to `yaml_emitter_set_output_file'
> | /usr/bin/ld: yamltree.c:(.text+0x933): undefined reference to `yaml_stream_start_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x93e): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x957): undefined reference to `yaml_document_start_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x962): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x983): undefined reference to `yaml_sequence_start_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x98e): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9ab): undefined reference to `yaml_sequence_end_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x9b6): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9c8): undefined reference to `yaml_document_end_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x9d3): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9e3): undefined reference to `yaml_stream_end_event_initialize'
> | /usr/bin/ld: yamltree.c:(.text+0x9ee): undefined reference to `yaml_emitter_emit'
> | /usr/bin/ld: yamltree.c:(.text+0x9fa): undefined reference to `yaml_emitter_delete'
> 

OK so there's a test to check if libyaml is available by looking if 
there's a file at $(PKG_CONFIG_SYSROOT_DIR)/usr/include/yaml.h. Then it 
uses pkg-config --cflags and pkg-config --libs on yaml-0.1 to find where 
that is located. I'm assuming the first one is found, possibly on the 
host distro, and the pkg-config possibly returns nothing as libyaml 
isn't available in the sysroot? This seems to be what 807bcd844afe 
("scripts/dtc: Fix pkg-config behavior under sysroot") is supposed to 
handle (specifically mentioning this fixes building with Yocto SDK). 
This commit is part of 2026.04, so not sure what's going on there. They 
say the error doesn't happen within Yocto because pseudo intercepts and 
rewrites the path, so this seems weird.

This logic is also borrowed from the kernel, which funnily enough 
dropped this entirely 4 years ago, in commit ef8795f3f1ce ("dt-bindings: 
kbuild: Use DTB files for validation"). So maybe something to work on 
with U-Boot to update DTC again (Kbuild and DTC updates aren't trivial 
in U-Boot as far as I understood as we have "lightly" forked it).

Cheers,
Quentin