[PATCH] Makefile: Separate libsbi objects for each platform

[Samuel Holland]

Hi E,

On 2025-09-17 2:50 PM, E Shattow wrote:
> Hi Samuel,
> 
> On 9/3/24 13:53, Samuel Holland wrote:
>> Since commit 22f38ee6c658 ("lib: sbi_ecall: Add Kconfig option for each
>> extension"), the libsbi object file contents depend on the Kconfig
>> configuration, so these files may be different across platforms. As a
>> result, each platform should get a separate copy of these object files,
>> corresponding to that platform's configuration.
>>
>> This change also allows building for multiple platforms in parallel.
>>
>> Fixes: 22f38ee6c658 ("lib: sbi_ecall: Add Kconfig option for each extension")
>> Signed-off-by: Samuel Holland <samuel.holland at sifive.com>
>> ---
>> Note that Kconfig is not used for the generic (no PLATFORM set) libsbi
>> build. But this is actually equivalent to all Kconfig options being
>> disabled. As a result, since the referenced commit, the generic libsbi
>> only supports the base SBI extension and none of the others. I don't
>> know how we want to fix this -- does anyone even use libsbi anymore?
>>
>>  Makefile | 12 ++++++++++--
>>  1 file changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/Makefile b/Makefile
>> index e5a0f19e..ccb2e138 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -264,11 +264,13 @@ include $(libsbiutils-object-mks)
>>  include $(firmware-object-mks)
>>  
>>  # Setup list of objects
>> -libsbi-objs-path-y=$(foreach obj,$(libsbi-objs-y),$(build_dir)/lib/sbi/$(obj))
>>  ifdef PLATFORM
>> +libsbi-objs-path-y=$(foreach obj,$(libsbi-objs-y),$(platform_build_dir)/lib/sbi/$(obj))
>>  libsbiutils-objs-path-y=$(foreach obj,$(libsbiutils-objs-y),$(platform_build_dir)/lib/utils/$(obj))
>>  platform-objs-path-y=$(foreach obj,$(platform-objs-y),$(platform_build_dir)/$(obj))
>>  firmware-bins-path-y=$(foreach bin,$(firmware-bins-y),$(platform_build_dir)/firmware/$(bin))
>> +else
>> +libsbi-objs-path-y=$(foreach obj,$(libsbi-objs-y),$(build_dir)/lib/sbi/$(obj))
>>  endif
>>  firmware-elfs-path-y=$(firmware-bins-path-y:.bin=.elf)
>>  firmware-objs-path-y=$(firmware-bins-path-y:.bin=.o)
>> @@ -504,9 +506,10 @@ compile_gen_dep = $(CMD_PREFIX)mkdir -p `dirname $(1)`; \
>>  	     echo " GEN-DEP   $(subst $(build_dir)/,,$(1))"; \
>>  	     echo "$(1:.dep=$(2)): $(3)" >> $(1)
>>  
>> -targets-y  = $(build_dir)/lib/libsbi.a
>>  ifdef PLATFORM
>>  targets-y += $(platform_build_dir)/lib/libplatsbi.a
>> +else
>> +targets-y  = $(build_dir)/lib/libsbi.a
>>  endif
>>  targets-y += $(firmware-bins-path-y)
>>  
>> @@ -565,6 +568,11 @@ $(platform_build_dir)/%.dep: $(platform_src_dir)/%.c $(KCONFIG_AUTOHEADER)
>>  $(platform_build_dir)/%.o: $(platform_src_dir)/%.c $(KCONFIG_AUTOHEADER)
>>  	$(call compile_cc,$@,$<)
>>  
>> +ifeq ($(BUILD_INFO),y)
>> +$(platform_build_dir)/lib/sbi/sbi_init.o: $(libsbi_dir)/sbi_init.c FORCE
>> +	$(call compile_cc,$@,$<)
>> +endif
>> +
>>  $(platform_build_dir)/%.dep: $(platform_src_dir)/%.S
>>  	$(call compile_as_dep,$@,$<)
>>  
> 
> Thanks for your reply [1] highlighting this patch. I recently
> encountered the issue, here are the detailed steps to reproduce:
> 
> `git clone --branch v2025.10-rc4
> https://source.denx.de/u-boot/u-boot.git /path/u-boot.git`
> `make O=/path/u-boot -C /path/u-boot.git starfive_visionfive2_defconfig`
> `make O=/path/u-boot -C /path/u-boot.git`
> 
> Image 'itb' is missing external blobs and is non-functional: opensbi
> /binman/itb/fit/images/opensbi/opensbi (fw_dynamic.bin):
>    See the documentation for your board. The OpenSBI git repo is at
>    https://github.com/riscv/opensbi.git
>    You may need to build fw_dynamic.bin first and re-build u-boot with
>    OPENSBI=/path/to/fw_dynamic.bin
> Image 'itb' has faked external blobs and is non-functional: fw_dynamic.bin
> 
> `git clone --branch v1.7
> https://github.com/riscv-software-src/opensbi.git /path/opensbi.git`
> `make O=/path/opensbi -C /path/opensbi.git`
> 
> # No such file fw_dynamic.bin, I am missing PLATFORM, try again:
> 
> `make O=/path/opensbi -C /path/opensbi.git PLATFORM=generic`
> `make O=/path/u-boot -C /path/u-boot.git
> OPENSBI=/path/opensbi/platform/generic/firmware/fw_payload.bin`
> 
> # U-Boot builds successfully however the result is defective in use
> 
> StarFive # reset
> resetting ...
> System reset not supported on this platform
> ### ERROR ### Please RESET the board ###
> 
> # Apply your patch, try again
> 
> `curl https://patchwork.ozlabs.org/series/422221/mbox/ | git -C
> /path/opensbi.git am`
> `make O=/path/opensbi -C /path/opensbi.git PLATFORM=generic`
> 
> # Result is no-op, must clean for patch to be effective

Thanks for testing! Yes, unfortunately this is still a problem that changes to
several files (especially objects.mk files) do not get picked up by the build
system, and it's a larger job to untangle. So currently it is best to assume you
need to clean the build directory after moving commits or applying a patch that
touches non-C files.

Regards,
Samuel

> `make O=/path/opensbi -C /path/opensbi.git clean`
> `make O=/path/opensbi -C /path/opensbi.git`
> `make O=/path/opensbi -C /path/opensbi.git PLATFORM=generic`
> `make O=/path/u-boot -C /path/u-boot.git
> OPENSBI=/path/opensbi/platform/generic/firmware/fw_payload.bin`
> 
> # U-Boot builds successfully and result is valid
> 
> StarFive # reset
> resetting ...
> U-Boot SPL 2025.10-rc4...
> 
> 1:
> https://lore.kernel.org/opensbi/0d6bf7c7-7605-4ad6-a35c-54efc5230fb8@sifive.com/
> 
> I'm thinking this should get a mention in the documentation in addition
> to the patch, if we're v1.7 and this is accepted for v1.8
> 
> "Releases prior to v1.8 would <technical description here>... when
> building OpenSBI you must clean your build directory between v1.8 and
> any earlier version for the new behavior to be effective."
> 
> With that, and without regard to uses other than PLATFORM=generic,
> 
> Tested-by: E Shattow <e at freeshell.de>