staging: Add tensorflow micro module.

[lgirdwood]

Integrates Tensorflow micro edition using xtensa optimized kernels into SOF as a module. WIP.

[lgirdwood]

@lyakh see the Readme for the extra steps needed to link archives to the llext module. We are linking a C and C++17 library to the llext module.

[lyakh]

@lgirdwood please try this version of your second patch.
0001-WIP-llext-cmake-Add-support-for-passing-more-config-.patch.txt
It works for me for a small dummy library. In llext CMakeLists.txt I then add

@@ -9,4 +9,7 @@ sof_llext_build("drc"
 		../drc_hifi4.c
 		../drc_math_hifi3.c
 	LIB openmodules
+	DEPENDS mytestlib
+	DEPEND_PATH /path/to/testlib/lib
+	INCLUDES /path/to/testlib/include
 )

[lgirdwood]

@lgirdwood please try this version of your second patch. 0001-WIP-llext-cmake-Add-support-for-passing-more-config-.patch.txt It works for me for a small dummy library. In llext CMakeLists.txt I then add

@@ -9,4 +9,7 @@ sof_llext_build("drc"
 		../drc_hifi4.c
 		../drc_math_hifi3.c
 	LIB openmodules
+	DEPENDS mytestlib
+	DEPEND_PATH /path/to/testlib/lib
+	INCLUDES /path/to/testlib/include
 )

Thanks, this seems to have done the trick, I've had to add c++, c m and gcc to the depends to link TFLM. Will cleanup and upstream it.

[lgirdwood]

Ready for staging.

[jsarha]

Tried to get this to compile, but it failed. The make file tried to look for sources under ${BASE_DIR}/tflm-micro , but the code is cloned under ${BASE_DIR}/tflite-micro.

[marcinszkudlinski]

Why special scripts/tensorflow-clone.sh script? We do use west, just add the repos there

[lgirdwood]

Tried to get this to compile, but it failed. The make file tried to look for sources under ${BASE_DIR}/tflm-micro , but the code is cloned under ${BASE_DIR}/tflite-micro.

Thanks fixed, the built-in config was using the wrong directory but llext was building fine.

[lgirdwood]

Why special scripts/tensorflow-clone.sh script? We do use west, just add the repos there

That was my initial intention too, but I could only get this working with a west manifest in each child module repo (and this would be difficult/slow to upstream). I think the script is fine to unblock us today as either someone with better west know how or updates to west could fix this in the future.

[kv2019i]

Some minor comments, but nothing worth blocking the PR.

[kv2019i]

This could be an overlay alike sof/app/shell_overlay.conf or sof/app/perf_overlay.conf.

[kv2019i]

This is more of a tflite API question, but wondering can "interpreter" be NULL/nullptr here? Maybe this is ok and the new operator is just overloaded.