am65x build issues

[Jan Kiszka]

On 30.04.20 23:16, Andrew F. Davis wrote:
> On 4/30/20 3:03 PM, Jan Kiszka wrote:
>> Hi all,
>>
>> I've noticed that building am65x_evm_a53_defconfig causes the dtbs to be
>> built twice, once for the main u-boot and once for the spl. This is
>> because of an extra dependency in mach-k3/config_secure.mk added by
>> 508369672ca3. Why should the produced dtbs depend on the target that
>> produces them? Why not simply this?
>>
>> diff --git a/arch/arm/mach-k3/config_secure.mk b/arch/arm/mach-k3/config_secure.mk
>> index 6d63c57665..cbe9b684fb 100644
>> --- a/arch/arm/mach-k3/config_secure.mk
>> +++ b/arch/arm/mach-k3/config_secure.mk
>> @@ -34,11 +34,8 @@ MKIMAGEFLAGS_u-boot.img_HS = -f auto -A $(ARCH) -T firmware -C none -O u-boot \
>>   	-n "U-Boot $(UBOOTRELEASE) for $(BOARD) board" -E \
>>   	$(patsubst %,-b arch/$(ARCH)/dts/%.dtb_HS,$(subst ",,$(CONFIG_OF_LIST)))
>>
>> -OF_LIST_TARGETS = $(patsubst %,arch/$(ARCH)/dts/%.dtb,$(subst ",,$(CONFIG_OF_LIST)))
>> -$(OF_LIST_TARGETS): dtbs
>> -
>>   u-boot-nodtb.bin_HS: u-boot-nodtb.bin FORCE
>>   	$(call if_changed,k3secureimg)
>>
>> -u-boot.img_HS: u-boot-nodtb.bin_HS u-boot.img $(patsubst %.dtb,%.dtb_HS,$(OF_LIST_TARGETS)) FORCE
>> +u-boot.img_HS: u-boot-nodtb.bin_HS u-boot.img dtbs FORCE
>>   	$(call if_changed,mkimage)
>>
>
>
> Because then no one will depend on the _HS versions of the .dtb files,
> so they wont get built.

Indeed, missed that.

>
> I agree it's a huge mess right now, the "correct" thing to do would be
> for the %.dtb_HS files to depend on their corresponding %.dtb files from
> which they are generated. Which they do, kinda. But Make doesn't seem
> smart enough to know that at the start, it checks for the .dtb files and
> fails instantly during the first round of parsing, due to the .dtb files
> not existing and no rules existing for them. The .dtb files are not
> being generated by a rule with their name so Make doesn't understand
> they will be generated later, because U-Boot uses scripting for dtbs and
> uses target "dtbs". So we are stuck depending on that until someone does
> some major rework of the U-Boot/Linux makefiles.. Feel free :D

loop_cmd = $(echo-cmd) $(cmd_$(1)) || exit;

dtbs_HS: dtbs FORCE
	$(foreach dtb, ..., $(call, loop_cmd, ...))

This avoids per-dtb rules and dependencies. But it will require some
variant of k3secureimg that takes the source as a parameter and not from
the rule's dependency list. This is the same pattern I currently play
with for injecting the public key into dtbs for fit image verification.
I'll see if I can get something building with am65x_hs_evm_a53_defconfig
to validate a concrete fix proposal.

Again my question: What can be the other broken dependency that causes
"make -j" failures?

Jan