[PATCH] dtc: Provide libfdt

[PATCH] dtc: Provide libfdt

[Andrew Jeffery]

Applications are appearing that depend on parsing flattened devicetree
in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
libfdt so application recipes can depend on it.

[1] https://github.com/open-power/pdbg

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
---
 meta/recipes-kernel/dtc/dtc.inc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/meta/recipes-kernel/dtc/dtc.inc b/meta/recipes-kernel/dtc/dtc.inc
index 0650e3c82e6d..d55c8af90660 100644
--- a/meta/recipes-kernel/dtc/dtc.inc
+++ b/meta/recipes-kernel/dtc/dtc.inc
@@ -5,6 +5,8 @@ SECTION = "bootloader"
 LICENSE = "GPLv2 | BSD"
 DEPENDS = "flex-native bison-native"
 
+PROVIDES += "libfdt"
+
 SRC_URI = "git://git.kernel.org/pub/scm/utils/dtc/dtc.git \
            file://make_install.patch \
            "
-- 
2.20.1

Re: [PATCH] dtc: Provide libfdt

[Adrian Bunk]

On Mon, Aug 05, 2019 at 12:42:11PM +0930, Andrew Jeffery wrote:
> Applications are appearing that depend on parsing flattened devicetree
> in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
> libfdt so application recipes can depend on it.
> 
> [1] https://github.com/open-power/pdbg

Shouldn't runtime dependencies on dtc already be autogenerated in this 
case when you have dtc in DEPENDS?

> Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
> ---
>  meta/recipes-kernel/dtc/dtc.inc | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/meta/recipes-kernel/dtc/dtc.inc b/meta/recipes-kernel/dtc/dtc.inc
> index 0650e3c82e6d..d55c8af90660 100644
> --- a/meta/recipes-kernel/dtc/dtc.inc
> +++ b/meta/recipes-kernel/dtc/dtc.inc
> @@ -5,6 +5,8 @@ SECTION = "bootloader"
>  LICENSE = "GPLv2 | BSD"
>  DEPENDS = "flex-native bison-native"
>  
> +PROVIDES += "libfdt"
>...

This should be a proper separate library package, so that applications 
depending on it stop pulling in the command line tools.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [PATCH] dtc: Provide libfdt

[Andrew Jeffery]

On Mon, 5 Aug 2019, at 14:35, Adrian Bunk wrote:
> On Mon, Aug 05, 2019 at 12:42:11PM +0930, Andrew Jeffery wrote:
> > Applications are appearing that depend on parsing flattened devicetree
> > in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
> > libfdt so application recipes can depend on it.
> > 
> > [1] https://github.com/open-power/pdbg
> 
> Shouldn't runtime dependencies on dtc already be autogenerated in this 
> case when you have dtc in DEPENDS?

"dtc" doesn't need to appear in depends for pdbg: "dtc-native" does for the
purpose of building the devicetrees shipped with the application, but "dtc"
doesn't and dtc(1) itself isn't required at runtime, rather we just need libfdt,
which brings up your point below.

> 
> > Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
> > ---
> >  meta/recipes-kernel/dtc/dtc.inc | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/meta/recipes-kernel/dtc/dtc.inc b/meta/recipes-kernel/dtc/dtc.inc
> > index 0650e3c82e6d..d55c8af90660 100644
> > --- a/meta/recipes-kernel/dtc/dtc.inc
> > +++ b/meta/recipes-kernel/dtc/dtc.inc
> > @@ -5,6 +5,8 @@ SECTION = "bootloader"
> >  LICENSE = "GPLv2 | BSD"
> >  DEPENDS = "flex-native bison-native"
> >  
> > +PROVIDES += "libfdt"
> >...
> 
> This should be a proper separate library package, so that applications 
> depending on it stop pulling in the command line tools.

Yeah, you're right, on reflection this was a bit of a hack.

Thanks for the feedback.

Andrew

Re: [PATCH] dtc: Provide libfdt

[Adrian Bunk]

On Mon, Aug 05, 2019 at 04:01:57PM +0930, Andrew Jeffery wrote:
> 
> 
> On Mon, 5 Aug 2019, at 14:35, Adrian Bunk wrote:
> > On Mon, Aug 05, 2019 at 12:42:11PM +0930, Andrew Jeffery wrote:
> > > Applications are appearing that depend on parsing flattened devicetree
> > > in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
> > > libfdt so application recipes can depend on it.
> > > 
> > > [1] https://github.com/open-power/pdbg
> > 
> > Shouldn't runtime dependencies on dtc already be autogenerated in this 
> > case when you have dtc in DEPENDS?
> 
> "dtc" doesn't need to appear in depends for pdbg: "dtc-native" does for the
> purpose of building the devicetrees shipped with the application, but "dtc"
> doesn't and dtc(1) itself isn't required at runtime, rather we just need libfdt,
>...

How do you link with libfdt without the non-native dtc in DEPENDS?

> Thanks for the feedback.
> 
> Andrew

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [PATCH] dtc: Provide libfdt

[Andrew Jeffery]

On Mon, 5 Aug 2019, at 16:13, Adrian Bunk wrote:
> On Mon, Aug 05, 2019 at 04:01:57PM +0930, Andrew Jeffery wrote:
> > 
> > 
> > On Mon, 5 Aug 2019, at 14:35, Adrian Bunk wrote:
> > > On Mon, Aug 05, 2019 at 12:42:11PM +0930, Andrew Jeffery wrote:
> > > > Applications are appearing that depend on parsing flattened devicetree
> > > > in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
> > > > libfdt so application recipes can depend on it.
> > > > 
> > > > [1] https://github.com/open-power/pdbg
> > > 
> > > Shouldn't runtime dependencies on dtc already be autogenerated in this 
> > > case when you have dtc in DEPENDS?
> > 
> > "dtc" doesn't need to appear in depends for pdbg: "dtc-native" does for the
> > purpose of building the devicetrees shipped with the application, but "dtc"
> > doesn't and dtc(1) itself isn't required at runtime, rather we just need libfdt,
> >...
> 
> How do you link with libfdt without the non-native dtc in DEPENDS?

Currently pdbg includes a copy of libfdt. However, the build system tests for
the presence of a system copy and will prefer it over the included copy.

Andrew

Re: [PATCH] dtc: Provide libfdt

[Ross Burton]

On 05/08/2019 04:12, Andrew Jeffery wrote:
> Applications are appearing that depend on parsing flattened devicetree
> in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
> libfdt so application recipes can depend on it.

Other recipes can just depend on dtc to get libftd build.

Ross

Re: [PATCH] dtc: Provide libfdt

[Andrew Jeffery]

On Tue, 6 Aug 2019, at 02:08, Ross Burton wrote:
> On 05/08/2019 04:12, Andrew Jeffery wrote:
> > Applications are appearing that depend on parsing flattened devicetree
> > in userspace on target devices, e.g. pdbg[1]. Mark dtc as providing
> > libfdt so application recipes can depend on it.
> 
> Other recipes can just depend on dtc to get libftd build.

Alright, lets leave it that way.

Andrew