[PATCH] binman: Add option for pointing to external description

[PATCH] binman: Add option for pointing to external description

[Michal Simek]

Adding binman node with target images description can be unwanted feature
but as of today there is no way to disable it.
Also on size constrained systems it is not useful to add binman description
to DTB.
Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
target from DTB for binman itself.

Signed-off-by: Michal Simek <michal.simek@amd.com>
---

 Makefile    |  2 +-
 lib/Kconfig | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index af24de4165e4..8043016ac279 100644
--- a/Makefile
+++ b/Makefile
@@ -1384,7 +1384,7 @@ cmd_binman = $(srctree)/tools/binman/binman $(if $(BINMAN_DEBUG),-D) \
 		$(foreach f,$(BINMAN_TOOLPATHS),--toolpath $(f)) \
                 --toolpath $(objtree)/tools \
 		$(if $(BINMAN_VERBOSE),-v$(BINMAN_VERBOSE)) \
-		build -u -d u-boot.dtb -O . -m \
+		build -u -d $(CONFIG_BINMAN_EXTERNAL_DTB) -O . -m \
 		--allow-missing $(if $(BINMAN_ALLOW_MISSING),--ignore-missing) \
 		-I . -I $(srctree) -I $(srctree)/board/$(BOARDDIR) \
 		$(foreach f,$(of_list_dirs),-I $(f)) -a of-list=$(of_list) \
diff --git a/lib/Kconfig b/lib/Kconfig
index 1448b4ac2d64..491f265012b8 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -45,6 +45,16 @@ config BINMAN_FDT
 	  locate entries in the firmware image. See binman.h for the available
 	  functionality.
 
+config BINMAN_EXTERNAL_DTB
+	string "External binman description"
+	depends on BINMAN
+	default "u-boot.dtb"
+	help
+	  This enables option to point to different DTB file with binman node which
+	  is outside of DTB used by the firmware. Use this option if information
+	  about generated images shouldn't be the part of target binary. Or on system
+	  with limited storage.
+
 config CC_OPTIMIZE_LIBS_FOR_SPEED
 	bool "Optimize libraries for speed"
 	help
-- 
2.43.0

Re: [PATCH] binman: Add option for pointing to external description

[Simon Glass]

Hi Michal,

On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
>
> Adding binman node with target images description can be unwanted feature
> but as of today there is no way to disable it.
> Also on size constrained systems it is not useful to add binman description
> to DTB.
> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
> target from DTB for binman itself.
>
> Signed-off-by: Michal Simek <michal.simek@amd.com>
> ---
>
>  Makefile    |  2 +-
>  lib/Kconfig | 10 ++++++++++
>  2 files changed, 11 insertions(+), 1 deletion(-)
>

Doesn't this defeat one of the purposes of Binman, i.e. to document
images? We do want the .dts to include the image description. What
sort of problem is this causing?

Regards,
Simon

Re: [PATCH] binman: Add option for pointing to external description

[Michal Simek]

Hi,

On 10/9/24 03:55, Simon Glass wrote:
> Hi Michal,
> 
> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
>>
>> Adding binman node with target images description can be unwanted feature
>> but as of today there is no way to disable it.
>> Also on size constrained systems it is not useful to add binman description
>> to DTB.
>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
>> target from DTB for binman itself.
>>
>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>> ---
>>
>>   Makefile    |  2 +-
>>   lib/Kconfig | 10 ++++++++++
>>   2 files changed, 11 insertions(+), 1 deletion(-)
>>
> 
> Doesn't this defeat one of the purposes of Binman, i.e. to document
> images? We do want the .dts to include the image description. What
> sort of problem is this causing?

We have two boot flows.
The first one (default one) is using Xilinx FSBL for SOM initialization with fit 
image (DTBS) + u-boot.elf + tfa.

The second one is using U-Boot SPL instead of FSBL. This flow is used by 
buildroot for example.

In perfect world I should describe both of these flows. I sent description for 
the second as RFC here.
https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com

but it is also reasonable to describe the first flow but I really don't want 
both descriptions ends up in the target image.

The second part is if you look at RFC and how fit-dtb.blob is composed. It is 
one DTB + DTBS which are composed from overlays.

xilinx_zynqmp_kria_defconfig has
CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"

That's why binman node should go to this DTB but because other images are 
composed with overlays binman node is spread to all DTBs inside FIT image.

It means one binman description is in fit-dtb.blob 14 times which is far from 
ideal.

Third part is that I can't see binman node in DT schema or bindings that's why I 
expect this will be reported and I can't see any code which removes it before 
handing off to OS which is required for System Ready IR.
And IIRC removing is also problematic for measured boot.

Thanks,
Michal

Re: [PATCH] binman: Add option for pointing to external description

[Simon Glass]

Hi Michal,

On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
>
> Hi,
>
> On 10/9/24 03:55, Simon Glass wrote:
> > Hi Michal,
> >
> > On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
> >>
> >> Adding binman node with target images description can be unwanted feature
> >> but as of today there is no way to disable it.
> >> Also on size constrained systems it is not useful to add binman description
> >> to DTB.
> >> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
> >> target from DTB for binman itself.
> >>
> >> Signed-off-by: Michal Simek <michal.simek@amd.com>
> >> ---
> >>
> >>   Makefile    |  2 +-
> >>   lib/Kconfig | 10 ++++++++++
> >>   2 files changed, 11 insertions(+), 1 deletion(-)
> >>
> >
> > Doesn't this defeat one of the purposes of Binman, i.e. to document
> > images? We do want the .dts to include the image description. What
> > sort of problem is this causing?
>
> We have two boot flows.
> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
> image (DTBS) + u-boot.elf + tfa.
>
> The second one is using U-Boot SPL instead of FSBL. This flow is used by
> buildroot for example.
>
> In perfect world I should describe both of these flows. I sent description for
> the second as RFC here.
> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com

OK I'll take a look.

>
> but it is also reasonable to describe the first flow but I really don't want
> both descriptions ends up in the target image.

Why not? Knowing what is in the firmware is one of the goals of Binman.

>
> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
> one DTB + DTBS which are composed from overlays.
>
> xilinx_zynqmp_kria_defconfig has
> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
>
> That's why binman node should go to this DTB but because other images are
> composed with overlays binman node is spread to all DTBs inside FIT image.
>
> It means one binman description is in fit-dtb.blob 14 times which is far from
> ideal.

Yes, but I think what you are saying is that U-Boot doesn't need the
description, so you don't need it to appear in the dtbs in the FIT. Is
that right?

If so, then I think we should add a way to remove it, in Binman,
perhaps with a property in the top-level binman image.

>
> Third part is that I can't see binman node in DT schema or bindings that's why I
> expect this will be reported and I can't see any code which removes it before
> handing off to OS which is required for System Ready IR.
> And IIRC removing is also problematic for measured boot.

I did start this e.g. [1] but have not got back to it. Help would be
appreciated if it is important to you. I am not sure about System
Ready IR, but we shouldn't need to remove this.

Also, please add an fdtmap somewhere so the image can be listed.

Regards,
Simon

[1] Documentation/devicetree/bindings/mtd/partitions/binman.yaml

Re: [PATCH] binman: Add option for pointing to external description

[Michal Simek]

On 10/9/24 23:14, Simon Glass wrote:
> Hi Michal,
> 
> On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
>>
>> Hi,
>>
>> On 10/9/24 03:55, Simon Glass wrote:
>>> Hi Michal,
>>>
>>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
>>>>
>>>> Adding binman node with target images description can be unwanted feature
>>>> but as of today there is no way to disable it.
>>>> Also on size constrained systems it is not useful to add binman description
>>>> to DTB.
>>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
>>>> target from DTB for binman itself.
>>>>
>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>> ---
>>>>
>>>>    Makefile    |  2 +-
>>>>    lib/Kconfig | 10 ++++++++++
>>>>    2 files changed, 11 insertions(+), 1 deletion(-)
>>>>
>>>
>>> Doesn't this defeat one of the purposes of Binman, i.e. to document
>>> images? We do want the .dts to include the image description. What
>>> sort of problem is this causing?
>>
>> We have two boot flows.
>> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
>> image (DTBS) + u-boot.elf + tfa.
>>
>> The second one is using U-Boot SPL instead of FSBL. This flow is used by
>> buildroot for example.
>>
>> In perfect world I should describe both of these flows. I sent description for
>> the second as RFC here.
>> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
> 
> OK I'll take a look.
> 
>>
>> but it is also reasonable to describe the first flow but I really don't want
>> both descriptions ends up in the target image.
> 
> Why not? Knowing what is in the firmware is one of the goals of Binman.

If this is single binary composition with clear layout then likely fine.
In our case where we target evaluation boards which can boot out of different 
boot devices it will be more confusing.
For these I want to generated all images also for testing purpose not only 
images which you will burn to qspi.

>>
>> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
>> one DTB + DTBS which are composed from overlays.
>>
>> xilinx_zynqmp_kria_defconfig has
>> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
>>
>> That's why binman node should go to this DTB but because other images are
>> composed with overlays binman node is spread to all DTBs inside FIT image.
>>
>> It means one binman description is in fit-dtb.blob 14 times which is far from
>> ideal.
> 
> Yes, but I think what you are saying is that U-Boot doesn't need the
> description, so you don't need it to appear in the dtbs in the FIT. Is
> that right?

Yes.
I know that there is a code around it but as of now I don't want to use any of 
this feature.

> If so, then I think we should add a way to remove it, in Binman,
> perhaps with a property in the top-level binman image.

Works for me but keep in your mind that for SOM this should be removed from all 
combinations and for me it is easier not to add that description there instead 
of adding it and removing it.

>>
>> Third part is that I can't see binman node in DT schema or bindings that's why I
>> expect this will be reported and I can't see any code which removes it before
>> handing off to OS which is required for System Ready IR.
>> And IIRC removing is also problematic for measured boot.
> 
> I did start this e.g. [1] but have not got back to it. Help would be
> appreciated if it is important to you. I am not sure about System
> Ready IR, but we shouldn't need to remove this.

I have seen this description but this target only boot images inside MTD.

SR IR requires DT to pass dt-schema. It means make no sense to add binman node 
to DT if this is going to be reported.

> Also, please add an fdtmap somewhere so the image can be listed.

Thanks for reminder. I remember this option and will explore to see what it does.

Thanks,
Michal

Re: [PATCH] binman: Add option for pointing to external description

[Simon Glass]

Hi Michal,

On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
>
>
>
> On 10/9/24 23:14, Simon Glass wrote:
> > Hi Michal,
> >
> > On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
> >>
> >> Hi,
> >>
> >> On 10/9/24 03:55, Simon Glass wrote:
> >>> Hi Michal,
> >>>
> >>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
> >>>>
> >>>> Adding binman node with target images description can be unwanted feature
> >>>> but as of today there is no way to disable it.
> >>>> Also on size constrained systems it is not useful to add binman description
> >>>> to DTB.
> >>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
> >>>> target from DTB for binman itself.
> >>>>
> >>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
> >>>> ---
> >>>>
> >>>>    Makefile    |  2 +-
> >>>>    lib/Kconfig | 10 ++++++++++
> >>>>    2 files changed, 11 insertions(+), 1 deletion(-)
> >>>>
> >>>
> >>> Doesn't this defeat one of the purposes of Binman, i.e. to document
> >>> images? We do want the .dts to include the image description. What
> >>> sort of problem is this causing?
> >>
> >> We have two boot flows.
> >> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
> >> image (DTBS) + u-boot.elf + tfa.
> >>
> >> The second one is using U-Boot SPL instead of FSBL. This flow is used by
> >> buildroot for example.
> >>
> >> In perfect world I should describe both of these flows. I sent description for
> >> the second as RFC here.
> >> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
> >
> > OK I'll take a look.
> >
> >>
> >> but it is also reasonable to describe the first flow but I really don't want
> >> both descriptions ends up in the target image.
> >
> > Why not? Knowing what is in the firmware is one of the goals of Binman.
>
> If this is single binary composition with clear layout then likely fine.
> In our case where we target evaluation boards which can boot out of different
> boot devices it will be more confusing.
> For these I want to generated all images also for testing purpose not only
> images which you will burn to qspi.
>
> >>
> >> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
> >> one DTB + DTBS which are composed from overlays.
> >>
> >> xilinx_zynqmp_kria_defconfig has
> >> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
> >>
> >> That's why binman node should go to this DTB but because other images are
> >> composed with overlays binman node is spread to all DTBs inside FIT image.
> >>
> >> It means one binman description is in fit-dtb.blob 14 times which is far from
> >> ideal.
> >
> > Yes, but I think what you are saying is that U-Boot doesn't need the
> > description, so you don't need it to appear in the dtbs in the FIT. Is
> > that right?
>
> Yes.
> I know that there is a code around it but as of now I don't want to use any of
> this feature.
>
> > If so, then I think we should add a way to remove it, in Binman,
> > perhaps with a property in the top-level binman image.
>
> Works for me but keep in your mind that for SOM this should be removed from all
> combinations and for me it is easier not to add that description there instead
> of adding it and removing it.

OK, I think you are saying that the description is repeated in each
.dtb since each is built by U-Boot's build system and then they are
added to the FIT.

But what is to stop people from not bothering to fill in the binman
description in U-Boot? I worry that vendors will have instructions
like 'build U-Boot with the in-tree devicetree, which has no binman
node, but pass this option to use this other file (not in mainline,
just our special vendor branch), just for Binman's use',

Where do you plan to keep this other file?

>
> >>
> >> Third part is that I can't see binman node in DT schema or bindings that's why I
> >> expect this will be reported and I can't see any code which removes it before
> >> handing off to OS which is required for System Ready IR.
> >> And IIRC removing is also problematic for measured boot.
> >
> > I did start this e.g. [1] but have not got back to it. Help would be
> > appreciated if it is important to you. I am not sure about System
> > Ready IR, but we shouldn't need to remove this.
>
> I have seen this description but this target only boot images inside MTD.
>
> SR IR requires DT to pass dt-schema. It means make no sense to add binman node
> to DT if this is going to be reported.

We need to get the schema in, then. IMO that whole idea (or checking
dt-schema) makes little sense, unless the schema includes firmware
nodes. Is there somewhere that explains why this is useful?

>
> > Also, please add an fdtmap somewhere so the image can be listed.
>
> Thanks for reminder. I remember this option and will explore to see what it does.

OK

Regards,
Simon

Re: [PATCH] binman: Add option for pointing to external description

[Michal Simek]

Hi Simon,

On 10/15/24 14:48, Simon Glass wrote:
> Hi Michal,
> 
> On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
>>
>>
>>
>> On 10/9/24 23:14, Simon Glass wrote:
>>> Hi Michal,
>>>
>>> On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
>>>>
>>>> Hi,
>>>>
>>>> On 10/9/24 03:55, Simon Glass wrote:
>>>>> Hi Michal,
>>>>>
>>>>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
>>>>>>
>>>>>> Adding binman node with target images description can be unwanted feature
>>>>>> but as of today there is no way to disable it.
>>>>>> Also on size constrained systems it is not useful to add binman description
>>>>>> to DTB.
>>>>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
>>>>>> target from DTB for binman itself.
>>>>>>
>>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>>>> ---
>>>>>>
>>>>>>     Makefile    |  2 +-
>>>>>>     lib/Kconfig | 10 ++++++++++
>>>>>>     2 files changed, 11 insertions(+), 1 deletion(-)
>>>>>>
>>>>>
>>>>> Doesn't this defeat one of the purposes of Binman, i.e. to document
>>>>> images? We do want the .dts to include the image description. What
>>>>> sort of problem is this causing?
>>>>
>>>> We have two boot flows.
>>>> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
>>>> image (DTBS) + u-boot.elf + tfa.
>>>>
>>>> The second one is using U-Boot SPL instead of FSBL. This flow is used by
>>>> buildroot for example.
>>>>
>>>> In perfect world I should describe both of these flows. I sent description for
>>>> the second as RFC here.
>>>> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
>>>
>>> OK I'll take a look.
>>>
>>>>
>>>> but it is also reasonable to describe the first flow but I really don't want
>>>> both descriptions ends up in the target image.
>>>
>>> Why not? Knowing what is in the firmware is one of the goals of Binman.
>>
>> If this is single binary composition with clear layout then likely fine.
>> In our case where we target evaluation boards which can boot out of different
>> boot devices it will be more confusing.
>> For these I want to generated all images also for testing purpose not only
>> images which you will burn to qspi.
>>
>>>>
>>>> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
>>>> one DTB + DTBS which are composed from overlays.
>>>>
>>>> xilinx_zynqmp_kria_defconfig has
>>>> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
>>>>
>>>> That's why binman node should go to this DTB but because other images are
>>>> composed with overlays binman node is spread to all DTBs inside FIT image.
>>>>
>>>> It means one binman description is in fit-dtb.blob 14 times which is far from
>>>> ideal.
>>>
>>> Yes, but I think what you are saying is that U-Boot doesn't need the
>>> description, so you don't need it to appear in the dtbs in the FIT. Is
>>> that right?
>>
>> Yes.
>> I know that there is a code around it but as of now I don't want to use any of
>> this feature.
>>
>>> If so, then I think we should add a way to remove it, in Binman,
>>> perhaps with a property in the top-level binman image.
>>
>> Works for me but keep in your mind that for SOM this should be removed from all
>> combinations and for me it is easier not to add that description there instead
>> of adding it and removing it.
> 
> OK, I think you are saying that the description is repeated in each
> .dtb since each is built by U-Boot's build system and then they are
> added to the FIT.

yep

> 
> But what is to stop people from not bothering to fill in the binman
> description in U-Boot? I worry that vendors will have instructions
> like 'build U-Boot with the in-tree devicetree, which has no binman
> node, but pass this option to use this other file (not in mainline,
> just our special vendor branch), just for Binman's use',
> 
> Where do you plan to keep this other file?

In u-boot repo of course. And all configurations which makes sense.
And pretty much if vendors wants to hide it they can no matter of this patch.
I understand your concern but vendors can do it today.

Thanks,
Michal

Re: [PATCH] binman: Add option for pointing to external description

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 4915 bytes --]

On Wed, Oct 16, 2024 at 07:59:59AM +0200, Michal Simek wrote:
> Hi Simon,
> 
> On 10/15/24 14:48, Simon Glass wrote:
> > Hi Michal,
> > 
> > On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
> > > 
> > > 
> > > 
> > > On 10/9/24 23:14, Simon Glass wrote:
> > > > Hi Michal,
> > > > 
> > > > On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
> > > > > 
> > > > > Hi,
> > > > > 
> > > > > On 10/9/24 03:55, Simon Glass wrote:
> > > > > > Hi Michal,
> > > > > > 
> > > > > > On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
> > > > > > > 
> > > > > > > Adding binman node with target images description can be unwanted feature
> > > > > > > but as of today there is no way to disable it.
> > > > > > > Also on size constrained systems it is not useful to add binman description
> > > > > > > to DTB.
> > > > > > > Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
> > > > > > > target from DTB for binman itself.
> > > > > > > 
> > > > > > > Signed-off-by: Michal Simek <michal.simek@amd.com>
> > > > > > > ---
> > > > > > > 
> > > > > > >     Makefile    |  2 +-
> > > > > > >     lib/Kconfig | 10 ++++++++++
> > > > > > >     2 files changed, 11 insertions(+), 1 deletion(-)
> > > > > > > 
> > > > > > 
> > > > > > Doesn't this defeat one of the purposes of Binman, i.e. to document
> > > > > > images? We do want the .dts to include the image description. What
> > > > > > sort of problem is this causing?
> > > > > 
> > > > > We have two boot flows.
> > > > > The first one (default one) is using Xilinx FSBL for SOM initialization with fit
> > > > > image (DTBS) + u-boot.elf + tfa.
> > > > > 
> > > > > The second one is using U-Boot SPL instead of FSBL. This flow is used by
> > > > > buildroot for example.
> > > > > 
> > > > > In perfect world I should describe both of these flows. I sent description for
> > > > > the second as RFC here.
> > > > > https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
> > > > 
> > > > OK I'll take a look.
> > > > 
> > > > > 
> > > > > but it is also reasonable to describe the first flow but I really don't want
> > > > > both descriptions ends up in the target image.
> > > > 
> > > > Why not? Knowing what is in the firmware is one of the goals of Binman.
> > > 
> > > If this is single binary composition with clear layout then likely fine.
> > > In our case where we target evaluation boards which can boot out of different
> > > boot devices it will be more confusing.
> > > For these I want to generated all images also for testing purpose not only
> > > images which you will burn to qspi.
> > > 
> > > > > 
> > > > > The second part is if you look at RFC and how fit-dtb.blob is composed. It is
> > > > > one DTB + DTBS which are composed from overlays.
> > > > > 
> > > > > xilinx_zynqmp_kria_defconfig has
> > > > > CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
> > > > > 
> > > > > That's why binman node should go to this DTB but because other images are
> > > > > composed with overlays binman node is spread to all DTBs inside FIT image.
> > > > > 
> > > > > It means one binman description is in fit-dtb.blob 14 times which is far from
> > > > > ideal.
> > > > 
> > > > Yes, but I think what you are saying is that U-Boot doesn't need the
> > > > description, so you don't need it to appear in the dtbs in the FIT. Is
> > > > that right?
> > > 
> > > Yes.
> > > I know that there is a code around it but as of now I don't want to use any of
> > > this feature.
> > > 
> > > > If so, then I think we should add a way to remove it, in Binman,
> > > > perhaps with a property in the top-level binman image.
> > > 
> > > Works for me but keep in your mind that for SOM this should be removed from all
> > > combinations and for me it is easier not to add that description there instead
> > > of adding it and removing it.
> > 
> > OK, I think you are saying that the description is repeated in each
> > .dtb since each is built by U-Boot's build system and then they are
> > added to the FIT.
> 
> yep
> 
> > 
> > But what is to stop people from not bothering to fill in the binman
> > description in U-Boot? I worry that vendors will have instructions
> > like 'build U-Boot with the in-tree devicetree, which has no binman
> > node, but pass this option to use this other file (not in mainline,
> > just our special vendor branch), just for Binman's use',
> > 
> > Where do you plan to keep this other file?
> 
> In u-boot repo of course. And all configurations which makes sense.
> And pretty much if vendors wants to hide it they can no matter of this patch.
> I understand your concern but vendors can do it today.

Will resolving this let us finally remove SPL_FIT_GENERATOR as well?

-- 
Tom

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Re: [PATCH] binman: Add option for pointing to external description

[Simon Glass]

Hi Michal,

On Wed, 16 Oct 2024 at 00:00, Michal Simek <michal.simek@amd.com> wrote:
>
> Hi Simon,
>
> On 10/15/24 14:48, Simon Glass wrote:
> > Hi Michal,
> >
> > On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
> >>
> >>
> >>
> >> On 10/9/24 23:14, Simon Glass wrote:
> >>> Hi Michal,
> >>>
> >>> On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
> >>>>
> >>>> Hi,
> >>>>
> >>>> On 10/9/24 03:55, Simon Glass wrote:
> >>>>> Hi Michal,
> >>>>>
> >>>>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
> >>>>>>
> >>>>>> Adding binman node with target images description can be unwanted feature
> >>>>>> but as of today there is no way to disable it.
> >>>>>> Also on size constrained systems it is not useful to add binman description
> >>>>>> to DTB.
> >>>>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
> >>>>>> target from DTB for binman itself.
> >>>>>>
> >>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
> >>>>>> ---
> >>>>>>
> >>>>>>     Makefile    |  2 +-
> >>>>>>     lib/Kconfig | 10 ++++++++++
> >>>>>>     2 files changed, 11 insertions(+), 1 deletion(-)
> >>>>>>
> >>>>>
> >>>>> Doesn't this defeat one of the purposes of Binman, i.e. to document
> >>>>> images? We do want the .dts to include the image description. What
> >>>>> sort of problem is this causing?
> >>>>
> >>>> We have two boot flows.
> >>>> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
> >>>> image (DTBS) + u-boot.elf + tfa.
> >>>>
> >>>> The second one is using U-Boot SPL instead of FSBL. This flow is used by
> >>>> buildroot for example.
> >>>>
> >>>> In perfect world I should describe both of these flows. I sent description for
> >>>> the second as RFC here.
> >>>> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
> >>>
> >>> OK I'll take a look.
> >>>
> >>>>
> >>>> but it is also reasonable to describe the first flow but I really don't want
> >>>> both descriptions ends up in the target image.
> >>>
> >>> Why not? Knowing what is in the firmware is one of the goals of Binman.
> >>
> >> If this is single binary composition with clear layout then likely fine.
> >> In our case where we target evaluation boards which can boot out of different
> >> boot devices it will be more confusing.
> >> For these I want to generated all images also for testing purpose not only
> >> images which you will burn to qspi.
> >>
> >>>>
> >>>> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
> >>>> one DTB + DTBS which are composed from overlays.
> >>>>
> >>>> xilinx_zynqmp_kria_defconfig has
> >>>> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
> >>>>
> >>>> That's why binman node should go to this DTB but because other images are
> >>>> composed with overlays binman node is spread to all DTBs inside FIT image.
> >>>>
> >>>> It means one binman description is in fit-dtb.blob 14 times which is far from
> >>>> ideal.
> >>>
> >>> Yes, but I think what you are saying is that U-Boot doesn't need the
> >>> description, so you don't need it to appear in the dtbs in the FIT. Is
> >>> that right?
> >>
> >> Yes.
> >> I know that there is a code around it but as of now I don't want to use any of
> >> this feature.
> >>
> >>> If so, then I think we should add a way to remove it, in Binman,
> >>> perhaps with a property in the top-level binman image.
> >>
> >> Works for me but keep in your mind that for SOM this should be removed from all
> >> combinations and for me it is easier not to add that description there instead
> >> of adding it and removing it.
> >
> > OK, I think you are saying that the description is repeated in each
> > .dtb since each is built by U-Boot's build system and then they are
> > added to the FIT.
>
> yep

OK, got it. I think we should add an way to make the binman node optional.

>
> >
> > But what is to stop people from not bothering to fill in the binman
> > description in U-Boot? I worry that vendors will have instructions
> > like 'build U-Boot with the in-tree devicetree, which has no binman
> > node, but pass this option to use this other file (not in mainline,
> > just our special vendor branch), just for Binman's use',
> >
> > Where do you plan to keep this other file?
>
> In u-boot repo of course. And all configurations which makes sense.
> And pretty much if vendors wants to hide it they can no matter of this patch.
> I understand your concern but vendors can do it today.

So what value are you going to use for BINMAN_EXTERNAL_DTB ? Is there
a patch for that? Perhaps it should be renamed, since it suggests that
the file is out of tree.

Regards,
Simon

Re: [PATCH] binman: Add option for pointing to external description

[Michal Simek]

On 10/17/24 19:54, Tom Rini wrote:
> On Wed, Oct 16, 2024 at 07:59:59AM +0200, Michal Simek wrote:
>> Hi Simon,
>>
>> On 10/15/24 14:48, Simon Glass wrote:
>>> Hi Michal,
>>>
>>> On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
>>>>
>>>>
>>>>
>>>> On 10/9/24 23:14, Simon Glass wrote:
>>>>> Hi Michal,
>>>>>
>>>>> On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> On 10/9/24 03:55, Simon Glass wrote:
>>>>>>> Hi Michal,
>>>>>>>
>>>>>>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
>>>>>>>>
>>>>>>>> Adding binman node with target images description can be unwanted feature
>>>>>>>> but as of today there is no way to disable it.
>>>>>>>> Also on size constrained systems it is not useful to add binman description
>>>>>>>> to DTB.
>>>>>>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
>>>>>>>> target from DTB for binman itself.
>>>>>>>>
>>>>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>>>>>> ---
>>>>>>>>
>>>>>>>>      Makefile    |  2 +-
>>>>>>>>      lib/Kconfig | 10 ++++++++++
>>>>>>>>      2 files changed, 11 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>
>>>>>>> Doesn't this defeat one of the purposes of Binman, i.e. to document
>>>>>>> images? We do want the .dts to include the image description. What
>>>>>>> sort of problem is this causing?
>>>>>>
>>>>>> We have two boot flows.
>>>>>> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
>>>>>> image (DTBS) + u-boot.elf + tfa.
>>>>>>
>>>>>> The second one is using U-Boot SPL instead of FSBL. This flow is used by
>>>>>> buildroot for example.
>>>>>>
>>>>>> In perfect world I should describe both of these flows. I sent description for
>>>>>> the second as RFC here.
>>>>>> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
>>>>>
>>>>> OK I'll take a look.
>>>>>
>>>>>>
>>>>>> but it is also reasonable to describe the first flow but I really don't want
>>>>>> both descriptions ends up in the target image.
>>>>>
>>>>> Why not? Knowing what is in the firmware is one of the goals of Binman.
>>>>
>>>> If this is single binary composition with clear layout then likely fine.
>>>> In our case where we target evaluation boards which can boot out of different
>>>> boot devices it will be more confusing.
>>>> For these I want to generated all images also for testing purpose not only
>>>> images which you will burn to qspi.
>>>>
>>>>>>
>>>>>> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
>>>>>> one DTB + DTBS which are composed from overlays.
>>>>>>
>>>>>> xilinx_zynqmp_kria_defconfig has
>>>>>> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
>>>>>>
>>>>>> That's why binman node should go to this DTB but because other images are
>>>>>> composed with overlays binman node is spread to all DTBs inside FIT image.
>>>>>>
>>>>>> It means one binman description is in fit-dtb.blob 14 times which is far from
>>>>>> ideal.
>>>>>
>>>>> Yes, but I think what you are saying is that U-Boot doesn't need the
>>>>> description, so you don't need it to appear in the dtbs in the FIT. Is
>>>>> that right?
>>>>
>>>> Yes.
>>>> I know that there is a code around it but as of now I don't want to use any of
>>>> this feature.
>>>>
>>>>> If so, then I think we should add a way to remove it, in Binman,
>>>>> perhaps with a property in the top-level binman image.
>>>>
>>>> Works for me but keep in your mind that for SOM this should be removed from all
>>>> combinations and for me it is easier not to add that description there instead
>>>> of adding it and removing it.
>>>
>>> OK, I think you are saying that the description is repeated in each
>>> .dtb since each is built by U-Boot's build system and then they are
>>> added to the FIT.
>>
>> yep
>>
>>>
>>> But what is to stop people from not bothering to fill in the binman
>>> description in U-Boot? I worry that vendors will have instructions
>>> like 'build U-Boot with the in-tree devicetree, which has no binman
>>> node, but pass this option to use this other file (not in mainline,
>>> just our special vendor branch), just for Binman's use',
>>>
>>> Where do you plan to keep this other file?
>>
>> In u-boot repo of course. And all configurations which makes sense.
>> And pretty much if vendors wants to hide it they can no matter of this patch.
>> I understand your concern but vendors can do it today.
> 
> Will resolving this let us finally remove SPL_FIT_GENERATOR as well?

Yes, that's the plan. I have that patch prepared but we need to resolve this first.

Thanks,
Michal

Re: [PATCH] binman: Add option for pointing to external description

[Michal Simek]

Hi Simon,

On 10/18/24 01:23, Simon Glass wrote:
> Hi Michal,
> 
> On Wed, 16 Oct 2024 at 00:00, Michal Simek <michal.simek@amd.com> wrote:
>>
>> Hi Simon,
>>
>> On 10/15/24 14:48, Simon Glass wrote:
>>> Hi Michal,
>>>
>>> On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
>>>>
>>>>
>>>>
>>>> On 10/9/24 23:14, Simon Glass wrote:
>>>>> Hi Michal,
>>>>>
>>>>> On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> On 10/9/24 03:55, Simon Glass wrote:
>>>>>>> Hi Michal,
>>>>>>>
>>>>>>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
>>>>>>>>
>>>>>>>> Adding binman node with target images description can be unwanted feature
>>>>>>>> but as of today there is no way to disable it.
>>>>>>>> Also on size constrained systems it is not useful to add binman description
>>>>>>>> to DTB.
>>>>>>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
>>>>>>>> target from DTB for binman itself.
>>>>>>>>
>>>>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>>>>>> ---
>>>>>>>>
>>>>>>>>      Makefile    |  2 +-
>>>>>>>>      lib/Kconfig | 10 ++++++++++
>>>>>>>>      2 files changed, 11 insertions(+), 1 deletion(-)
>>>>>>>>
>>>>>>>
>>>>>>> Doesn't this defeat one of the purposes of Binman, i.e. to document
>>>>>>> images? We do want the .dts to include the image description. What
>>>>>>> sort of problem is this causing?
>>>>>>
>>>>>> We have two boot flows.
>>>>>> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
>>>>>> image (DTBS) + u-boot.elf + tfa.
>>>>>>
>>>>>> The second one is using U-Boot SPL instead of FSBL. This flow is used by
>>>>>> buildroot for example.
>>>>>>
>>>>>> In perfect world I should describe both of these flows. I sent description for
>>>>>> the second as RFC here.
>>>>>> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
>>>>>
>>>>> OK I'll take a look.
>>>>>
>>>>>>
>>>>>> but it is also reasonable to describe the first flow but I really don't want
>>>>>> both descriptions ends up in the target image.
>>>>>
>>>>> Why not? Knowing what is in the firmware is one of the goals of Binman.
>>>>
>>>> If this is single binary composition with clear layout then likely fine.
>>>> In our case where we target evaluation boards which can boot out of different
>>>> boot devices it will be more confusing.
>>>> For these I want to generated all images also for testing purpose not only
>>>> images which you will burn to qspi.
>>>>
>>>>>>
>>>>>> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
>>>>>> one DTB + DTBS which are composed from overlays.
>>>>>>
>>>>>> xilinx_zynqmp_kria_defconfig has
>>>>>> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
>>>>>>
>>>>>> That's why binman node should go to this DTB but because other images are
>>>>>> composed with overlays binman node is spread to all DTBs inside FIT image.
>>>>>>
>>>>>> It means one binman description is in fit-dtb.blob 14 times which is far from
>>>>>> ideal.
>>>>>
>>>>> Yes, but I think what you are saying is that U-Boot doesn't need the
>>>>> description, so you don't need it to appear in the dtbs in the FIT. Is
>>>>> that right?
>>>>
>>>> Yes.
>>>> I know that there is a code around it but as of now I don't want to use any of
>>>> this feature.
>>>>
>>>>> If so, then I think we should add a way to remove it, in Binman,
>>>>> perhaps with a property in the top-level binman image.
>>>>
>>>> Works for me but keep in your mind that for SOM this should be removed from all
>>>> combinations and for me it is easier not to add that description there instead
>>>> of adding it and removing it.
>>>
>>> OK, I think you are saying that the description is repeated in each
>>> .dtb since each is built by U-Boot's build system and then they are
>>> added to the FIT.
>>
>> yep
> 
> OK, got it. I think we should add an way to make the binman node optional.

I expect binman node is optional even today. No binman no means no image generation.

Also I have one more use case where adding binman node can be misleading.
With our FSBL boot flow only u-boot.elf is taken. If binman node in appended dtb 
is there people can think that bootimage was compose by binman but it doesn't 
need to be the case. That's why I want to have freedom and move decision about 
composing images to end users.


>>>
>>> But what is to stop people from not bothering to fill in the binman
>>> description in U-Boot? I worry that vendors will have instructions
>>> like 'build U-Boot with the in-tree devicetree, which has no binman
>>> node, but pass this option to use this other file (not in mainline,
>>> just our special vendor branch), just for Binman's use',
>>>
>>> Where do you plan to keep this other file?
>>
>> In u-boot repo of course. And all configurations which makes sense.
>> And pretty much if vendors wants to hide it they can no matter of this patch.
>> I understand your concern but vendors can do it today.
> 
> So what value are you going to use for BINMAN_EXTERNAL_DTB ? Is there
> a patch for that?

Sorry I see that I didn't include defconfig change. In SOM case it should look 
like this.

CONFIG_BINMAN_EXTERNAL_DTB="arch/arm/dts/zynqmp-som-binman.dtb"

I had it as the part of SPL_FIT_GENERATOR removal.

> Perhaps it should be renamed, since it suggests that
> the file is out of tree.

I am fine with renaming it. Do you have any suggestion?

Thanks,
Michal

Re: [PATCH] binman: Add option for pointing to external description

[Simon Glass]

Hi Michal,

On Fri, 18 Oct 2024 at 00:02, Michal Simek <michal.simek@amd.com> wrote:
>
> Hi Simon,
>
> On 10/18/24 01:23, Simon Glass wrote:
> > Hi Michal,
> >
> > On Wed, 16 Oct 2024 at 00:00, Michal Simek <michal.simek@amd.com> wrote:
> >>
> >> Hi Simon,
> >>
> >> On 10/15/24 14:48, Simon Glass wrote:
> >>> Hi Michal,
> >>>
> >>> On Thu, 10 Oct 2024 at 07:03, Michal Simek <michal.simek@amd.com> wrote:
> >>>>
> >>>>
> >>>>
> >>>> On 10/9/24 23:14, Simon Glass wrote:
> >>>>> Hi Michal,
> >>>>>
> >>>>> On Wed, 9 Oct 2024 at 07:21, Michal Simek <michal.simek@amd.com> wrote:
> >>>>>>
> >>>>>> Hi,
> >>>>>>
> >>>>>> On 10/9/24 03:55, Simon Glass wrote:
> >>>>>>> Hi Michal,
> >>>>>>>
> >>>>>>> On Mon, 7 Oct 2024 at 07:05, Michal Simek <michal.simek@amd.com> wrote:
> >>>>>>>>
> >>>>>>>> Adding binman node with target images description can be unwanted feature
> >>>>>>>> but as of today there is no way to disable it.
> >>>>>>>> Also on size constrained systems it is not useful to add binman description
> >>>>>>>> to DTB.
> >>>>>>>> Introduce BINMAN_EXTERNAL_DTB Kconfig symbol which allows separate DTB for
> >>>>>>>> target from DTB for binman itself.
> >>>>>>>>
> >>>>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
> >>>>>>>> ---
> >>>>>>>>
> >>>>>>>>      Makefile    |  2 +-
> >>>>>>>>      lib/Kconfig | 10 ++++++++++
> >>>>>>>>      2 files changed, 11 insertions(+), 1 deletion(-)
> >>>>>>>>
> >>>>>>>
> >>>>>>> Doesn't this defeat one of the purposes of Binman, i.e. to document
> >>>>>>> images? We do want the .dts to include the image description. What
> >>>>>>> sort of problem is this causing?
> >>>>>>
> >>>>>> We have two boot flows.
> >>>>>> The first one (default one) is using Xilinx FSBL for SOM initialization with fit
> >>>>>> image (DTBS) + u-boot.elf + tfa.
> >>>>>>
> >>>>>> The second one is using U-Boot SPL instead of FSBL. This flow is used by
> >>>>>> buildroot for example.
> >>>>>>
> >>>>>> In perfect world I should describe both of these flows. I sent description for
> >>>>>> the second as RFC here.
> >>>>>> https://lore.kernel.org/r/de1b8dbabd5ab7f20d7aac217ec4f5074d39f1da.1728462767.git.michal.simek@amd.com
> >>>>>
> >>>>> OK I'll take a look.
> >>>>>
> >>>>>>
> >>>>>> but it is also reasonable to describe the first flow but I really don't want
> >>>>>> both descriptions ends up in the target image.
> >>>>>
> >>>>> Why not? Knowing what is in the firmware is one of the goals of Binman.
> >>>>
> >>>> If this is single binary composition with clear layout then likely fine.
> >>>> In our case where we target evaluation boards which can boot out of different
> >>>> boot devices it will be more confusing.
> >>>> For these I want to generated all images also for testing purpose not only
> >>>> images which you will burn to qspi.
> >>>>
> >>>>>>
> >>>>>> The second part is if you look at RFC and how fit-dtb.blob is composed. It is
> >>>>>> one DTB + DTBS which are composed from overlays.
> >>>>>>
> >>>>>> xilinx_zynqmp_kria_defconfig has
> >>>>>> CONFIG_DEFAULT_DEVICE_TREE="zynqmp-smk-k26-revA"
> >>>>>>
> >>>>>> That's why binman node should go to this DTB but because other images are
> >>>>>> composed with overlays binman node is spread to all DTBs inside FIT image.
> >>>>>>
> >>>>>> It means one binman description is in fit-dtb.blob 14 times which is far from
> >>>>>> ideal.
> >>>>>
> >>>>> Yes, but I think what you are saying is that U-Boot doesn't need the
> >>>>> description, so you don't need it to appear in the dtbs in the FIT. Is
> >>>>> that right?
> >>>>
> >>>> Yes.
> >>>> I know that there is a code around it but as of now I don't want to use any of
> >>>> this feature.
> >>>>
> >>>>> If so, then I think we should add a way to remove it, in Binman,
> >>>>> perhaps with a property in the top-level binman image.
> >>>>
> >>>> Works for me but keep in your mind that for SOM this should be removed from all
> >>>> combinations and for me it is easier not to add that description there instead
> >>>> of adding it and removing it.
> >>>
> >>> OK, I think you are saying that the description is repeated in each
> >>> .dtb since each is built by U-Boot's build system and then they are
> >>> added to the FIT.
> >>
> >> yep
> >
> > OK, got it. I think we should add an way to make the binman node optional.
>
> I expect binman node is optional even today. No binman no means no image generation.
>
> Also I have one more use case where adding binman node can be misleading.
> With our FSBL boot flow only u-boot.elf is taken. If binman node in appended dtb
> is there people can think that bootimage was compose by binman but it doesn't
> need to be the case. That's why I want to have freedom and move decision about
> composing images to end users.

OK.

>
>
> >>>
> >>> But what is to stop people from not bothering to fill in the binman
> >>> description in U-Boot? I worry that vendors will have instructions
> >>> like 'build U-Boot with the in-tree devicetree, which has no binman
> >>> node, but pass this option to use this other file (not in mainline,
> >>> just our special vendor branch), just for Binman's use',
> >>>
> >>> Where do you plan to keep this other file?
> >>
> >> In u-boot repo of course. And all configurations which makes sense.
> >> And pretty much if vendors wants to hide it they can no matter of this patch.
> >> I understand your concern but vendors can do it today.
> >
> > So what value are you going to use for BINMAN_EXTERNAL_DTB ? Is there
> > a patch for that?
>
> Sorry I see that I didn't include defconfig change. In SOM case it should look
> like this.
>
> CONFIG_BINMAN_EXTERNAL_DTB="arch/arm/dts/zynqmp-som-binman.dtb"
>
> I had it as the part of SPL_FIT_GENERATOR removal.
>
> > Perhaps it should be renamed, since it suggests that
> > the file is out of tree.
>
> I am fine with renaming it. Do you have any suggestion?

Yes, just CONFIG_BINMAN_DTB seems OK to me. Please make sure that the
path has a "./" prefix so that absolute paths are not allowed. Let's
see how this goes in practice.

The Makefile logic should be adjusted to put the CONFIG value into a
separate variable, so that CONFIG_BINMAN_DTB can be empty and the
Makefile then defaults it to u-boot.dtb

I am thinking at some point we might want binman to accept both dtbs,
but let's see...

Regards,
SImon