cmake: Parse ZEPHYR_TOOLCHAIN_VARIANT in SDK instead of Zephyr

When ZEPHYR_TOOLCHAIN_VARIANT is of the form toolchain/compiler, it
needs to be split into the toolchain (which overwrites
ZEPHYR_TOOLCHAIN_VARIANT) and compiler (stored in
TOOLCHAIN_VARIANT_COMPILER).

Otherwise, when defined, it is left alone. When undefined it is set to
"zephyr".

Finally, if the value is "zephyr" and no TOOLCHAIN_VARIANT_COMPILER
setting is present, then TOOLCHAIN_VARIANT_COMPILER is set to "gnu".

This allows existing configurations which set ZEPHYR_TOOLCHAIN_VARIANT
to "zephyr" to work with the new SDK and allows Zephyr to easily
support both old and new variable settings during the SDK transition
period.

Finally, write both values into the environment so that Kconfig can
use them.

Signed-off-by: Keith Packard <[email protected]>

Author: keith-packard

cmake/Zephyr-sdkConfig.cmake

@@ -12,10 +12,26 @@ set(SDK_MAJOR_MINOR_MICRO ${SDK_VERSION})
 get_filename_component(ZEPHYR_SDK_INSTALL_DIR ${CMAKE_CURRENT_LIST_DIR}/.. ABSOLUTE)
 set(ZEPHYR_SDK_INSTALL_DIR ${ZEPHYR_SDK_INSTALL_DIR})
 
-if(NOT DEFINED ZEPHYR_TOOLCHAIN_VARIANT)
-  set(ZEPHYR_TOOLCHAIN_VARIANT "zephyr/gnu")
+# Check and see if the user specified a toolchain
+if(DEFINED ZEPHYR_TOOLCHAIN_VARIANT)
+  # Check and see if the specified toolchain includes a compiler
+  if(ZEPHYR_TOOLCHAIN_VARIANT MATCHES "^([^/])+/([^/]+)$")
+    # Replace any existing values with the provided components
+    set(ZEPHYR_TOOLCHAIN_VARIANT "${CMAKE_MATCH_1}" CACHE STRING "toolchain" FORCE)
+    set(TOOLCHAIN_VARIANT_COMPILER "${CMAKE_MATCH_2}" CACHE STRING "compiler" FORCE)
+  endif()
+else()
+  set(ZEPHYR_TOOLCHAIN_VARIANT "zephyr")
 endif()
 
+# When using the Zephyr SDK, use the gnu compiler by default
+if(ZEPHYR_TOOLCHAIN_VARIANT STREQUAL "zephyr" AND NOT DEFINED TOOLCHAIN_VARIANT_COMPILER)
+  set(TOOLCHAIN_VARIANT_COMPILER "gnu")
+endif()
+
+set(ENV{ZEPHYR_TOOLCHAIN_VARIANT} "${ZEPHYR_TOOLCHAIN_VARIANT}")
+set(ENV{TOOLCHAIN_VARIANT_COMPILER} "${TOOLCHAIN_VARIANT_COMPILER}")
+
 # Those are CMake package parameters.
 set(Zephyr-sdk_FOUND True)
 set(Zephyr-sdk_DIR   ${ZEPHYR_SDK_INSTALL_DIR})