cmake: Add seL4Config.cmake include CMakeLists.txt

seL4Config.cmake is responsible for generating a valid
CMAKE_TOOLCHAIN_FILE and setting up platform config options at the start
of the build. The CMAKE_TOOLCHAIN_FILE variable has to be set before the
first cmake `project()` function is processed to take effect.
Previously this file was required to be imported in a CMake script
before the kernel's CMakeLists.txt could be processed. This prevented
the main CMakeLists.txt file from being used without an additional
configuration file:
cmake -G Ninja -C ../configs/ARM_verified.cmake ../

Now it is possible to do:
cmake -G Ninja -DKernelPlatform=imx6 -DKernelARMPlatform=sabre ../

This should make it easier to invoke CMake for building kernel
configurations from other build environments.

Because this file is now imported in the Kernel's CMakeLists.txt
context, there is no longer a requirement to save all the intermediate
settings into the cache and then read them out again.

Signed-off-by: Kent McLeod <kent@kry10.com>

CMakeLists.txt

@@ -6,6 +6,8 @@
 
 cmake_minimum_required(VERSION 3.8.2)
 include(CheckCCompilerFlag)
+
+include(${CMAKE_CURRENT_LIST_DIR}/configs/seL4Config.cmake)
 project(seL4 C ASM)
 
 # First find our helpers
@@ -36,20 +38,6 @@ RequireTool(INVOCATION_ID_GEN_PATH invocation_header_gen.py)
 RequireTool(SYSCALL_ID_GEN_PATH syscall_header_gen.py)
 RequireTool(XMLLINT_PATH xmllint.sh)
 
-set(c_sources "")
-set(asm_sources "")
-set(bf_declarations "")
-foreach(file IN LISTS config_c_sources)
-    list(APPEND c_sources "${CMAKE_CURRENT_SOURCE_DIR}/${file}")
-endforeach()
-foreach(file IN LISTS config_asm_sources)
-    list(APPEND asm_sources "${CMAKE_CURRENT_SOURCE_DIR}/${file}")
-endforeach()
-foreach(file IN LISTS config_bf_declarations)
-    list(APPEND bf_declarations "${CMAKE_CURRENT_SOURCE_DIR}/${file}")
-endforeach()
-set(KernelDTSList "${config_KernelDTSList}")
-
 # Process the configuration scripts
 include(config.cmake)
 

config.cmake

@@ -6,8 +6,6 @@
 
 cmake_minimum_required(VERSION 3.7.2)
 
-set(configure_string "${config_configure_string}")
-
 config_option(
     KernelIsMCS KERNEL_MCS "Use the MCS kernel configuration, which is not verified."
     DEFAULT OFF
@@ -49,7 +47,7 @@ set_property(
 )
 
 # These options are now set in seL4Config.cmake
-if(DEFINED CONFIGURE_MAX_IRQ)
+if(DEFINED CALLED_declare_default_headers)
     # calculate the irq cnode size based on MAX_IRQ
     if("${KernelArch}" STREQUAL "riscv")
         set(MAX_IRQ "${CONFIGURE_PLIC_MAX_NUM_INT}")

configs/ARM_HYP_verified.cmake

@@ -24,4 +24,3 @@ set(KernelNumDomains 16 CACHE STRING "")
 set(KernelMaxNumBootinfoUntypedCap 166 CACHE STRING "")
 set(KernelRootCNodeSizeBits 19 CACHE STRING "")
 set(KernelMaxNumBootinfoUntypedCaps 50 CACHE STRING "")
-include(${CMAKE_CURRENT_LIST_DIR}/seL4Config.cmake)

configs/ARM_MCS_verified.cmake

@@ -23,4 +23,3 @@ set(KernelNumDomains 16 CACHE STRING "")
 set(KernelMaxNumBootinfoUntypedCap 166 CACHE STRING "")
 set(KernelIsMCS ON CACHE BOOL "")
 set(KernelStaticMaxPeriodUs "(60 * 60 * MS_IN_S * US_IN_MS)" CACHE STRING "")
-include(${CMAKE_CURRENT_LIST_DIR}/seL4Config.cmake)

configs/ARM_verified.cmake

@@ -21,4 +21,3 @@ set(KernelFastpath ON CACHE BOOL "")
 set(KernelPrinting OFF CACHE BOOL "")
 set(KernelNumDomains 16 CACHE STRING "")
 set(KernelMaxNumBootinfoUntypedCap 166 CACHE STRING "")
-include(${CMAKE_CURRENT_LIST_DIR}/seL4Config.cmake)

configs/RISCV64_MCS_verified.cmake

@@ -28,4 +28,3 @@ set(KernelIsMCS ON CACHE BOOL "")
 set(KernelStaticMaxPeriodUs "(60 * 60 * MS_IN_S * US_IN_MS)" CACHE STRING "")
 set(KernelClzNoBuiltin ON CACHE BOOL "")
 set(KernelCtzNoBuiltin ON CACHE BOOL "")
-include(${CMAKE_CURRENT_LIST_DIR}/seL4Config.cmake)

configs/RISCV64_verified.cmake

@@ -26,4 +26,3 @@ set(KernelRootCNodeSizeBits 19 CACHE STRING "")
 set(KernelMaxNumBootinfoUntypedCaps 50 CACHE STRING "")
 set(KernelClzNoBuiltin ON CACHE BOOL "")
 set(KernelCtzNoBuiltin ON CACHE BOOL "")
-include(${CMAKE_CURRENT_LIST_DIR}/seL4Config.cmake)

configs/X64_verified.cmake

@@ -24,4 +24,3 @@ set(KernelMaxNumBootinfoUntypedCap 166 CACHE STRING "")
 set(KernelRootCNodeSizeBits 19 CACHE STRING "")
 set(KernelMaxNumBootinfoUntypedCaps 50 CACHE STRING "")
 set(KernelFSGSBase "inst" CACHE STRING "")
-include(${CMAKE_CURRENT_LIST_DIR}/seL4Config.cmake)

configs/seL4Config.cmake

@@ -11,6 +11,7 @@ set(configure_string "")
 set(c_sources "")
 set(asm_sources "")
 set(bf_declarations "")
+set(KernelDTSList "")
 
 include(${CMAKE_CURRENT_LIST_DIR}/../tools/internal.cmake)
 include(${CMAKE_CURRENT_LIST_DIR}/../tools/helpers.cmake)
@@ -108,51 +109,21 @@ macro(fallback_declare_seL4_arch_default default_arch)
     declare_seL4_arch(${default_arch})
 endmacro()
 
-unset(CONFIGURE_PLIC_MAX_NUM_INT CACHE)
-unset(CONFIGURE_TIMER_FREQUENCY CACHE)
-unset(CONFIGURE_MAX_IRQ CACHE)
-unset(CONFIGURE_NUM_PPI CACHE)
-unset(CONFIGURE_INTERRUPT_CONTROLLER CACHE)
-unset(CONFIGURE_TIMER CACHE)
-unset(CONFIGURE_SMMU CACHE)
-unset(CONFIGURE_CLK_SHIFT CACHE)
-unset(CONFIGURE_CLK_MAGIC CACHE)
-unset(CONFIGURE_KERNEL_WCET CACHE)
-unset(CONFIGURE_TIMER_PRECISION CACHE)
-# CONFIGURE_MAX_CB and CONFIGURE_MAX_SID are related to the kernel SMMU on Arm.
-unset(CONFIGURE_MAX_SID CACHE)
-unset(CONFIGURE_MAX_CB CACHE)
-
 # CLK_SHIFT and CLK_MAGIC are generated from tools/reciprocal.py
 # based on the TIMER_CLK_HZ to simulate division.
 # This could be moved to a cmake function
 # in future to build the values on the first build. Note the calculation
 # can take a long time though.
-function(declare_default_headers)
+macro(declare_default_headers)
     cmake_parse_arguments(
-        PARSE_ARGV
-        0
         CONFIGURE
         ""
         "TIMER_FREQUENCY;MAX_IRQ;NUM_PPI;PLIC_MAX_NUM_INT;INTERRUPT_CONTROLLER;TIMER;SMMU;CLK_SHIFT;CLK_MAGIC;KERNEL_WCET;TIMER_PRECISION;MAX_SID;MAX_CB"
         ""
+        ${ARGN}
     )
-    set(CONFIGURE_TIMER_FREQUENCY "${CONFIGURE_TIMER_FREQUENCY}" CACHE INTERNAL "")
-    set(CONFIGURE_MAX_IRQ "${CONFIGURE_MAX_IRQ}" CACHE INTERNAL "")
-    set(CONFIGURE_NUM_PPI "${CONFIGURE_NUM_PPI}" CACHE INTERNAL "")
-    set(CONFIGURE_PLIC_MAX_NUM_INT "${CONFIGURE_PLIC_MAX_NUM_INT}" CACHE INTERNAL "")
-    set(CONFIGURE_INTERRUPT_CONTROLLER "${CONFIGURE_INTERRUPT_CONTROLLER}" CACHE INTERNAL "")
-    set(CONFIGURE_TIMER "${CONFIGURE_TIMER}" CACHE INTERNAL "")
-    set(CONFIGURE_SMMU "${CONFIGURE_SMMU}" CACHE INTERNAL "")
-    set(CONFIGURE_CLK_SHIFT "${CONFIGURE_CLK_SHIFT}" CACHE INTERNAL "")
-    set(CONFIGURE_CLK_MAGIC "${CONFIGURE_CLK_MAGIC}" CACHE INTERNAL "")
-    set(CONFIGURE_KERNEL_WCET "${CONFIGURE_KERNEL_WCET}" CACHE INTERNAL "")
-    if(DEFINED CONFIGURE_TIMER_PRECISION)
-        set(CONFIGURE_TIMER_PRECISION "${CONFIGURE_TIMER_PRECISION}" CACHE INTERNAL "")
-    endif()
-    set(CONFIGURE_MAX_SID "${CONFIGURE_MAX_SID}" CACHE INTERNAL "")
-    set(CONFIGURE_MAX_CB "${CONFIGURE_MAX_CB}" CACHE INTERNAL "")
-endfunction()
+    set(CALLED_declare_default_headers 1)
+endmacro()
 
 # For all of the common variables we set a default value here if they haven't
 # been set by a platform.
@@ -186,7 +157,6 @@ unset(KernelArmCPU CACHE)
 unset(KernelArmArmV CACHE)
 
 # Blacklist platforms without MCS support
-unset(KernelPlatformSupportsMCS CACHE)
 set(KernelPlatformSupportsMCS ON)
 
 file(GLOB result ${CMAKE_CURRENT_LIST_DIR}/../src/plat/*/config.cmake)
@@ -215,7 +185,6 @@ config_set(KernelArchArmV7ve ARCH_ARM_V7VE "${KernelArchArmV7ve}")
 config_set(KernelArchArmV8a ARCH_ARM_V8A "${KernelArchArmV8a}")
 config_set(KernelArmSMMU ARM_SMMU "${KernelArmSMMU}")
 config_set(KernelAArch64SErrorIgnore AARCH64_SERROR_IGNORE "${KernelAArch64SErrorIgnore}")
-set(KernelPlatformSupportsMCS "${KernelPlatformSupportsMCS}" CACHE INTERNAL "" FORCE)
 
 # Check for v7ve before v7a as v7ve is a superset and we want to set the
 # actual armv to that, but leave armv7a config enabled for anything that
@@ -254,46 +223,6 @@ if(KernelArchARM)
     config_set(KernelArmMach ARM_MACH "${KernelArmMach}")
 endif()
 
-set(config_configure_string ${configure_string} CACHE INTERNAL "")
-set(config_c_sources "")
-set(config_asm_sources "")
-set(config_bf_declarations "")
-foreach(file IN LISTS c_sources)
-    string(
-        REPLACE
-            "${CMAKE_CURRENT_SOURCE_DIR}/"
-            ""
-            file
-            "${file}"
-    )
-    list(APPEND config_c_sources "${file}")
-endforeach()
-foreach(file IN LISTS asm_sources)
-    string(
-        REPLACE
-            "${CMAKE_CURRENT_SOURCE_DIR}/"
-            ""
-            file
-            "${file}"
-    )
-    list(APPEND config_asm_sources "${file}")
-endforeach()
-foreach(file IN LISTS bf_declarations)
-    string(
-        REPLACE
-            "${CMAKE_CURRENT_SOURCE_DIR}/"
-            ""
-            file
-            "${file}"
-    )
-    list(APPEND config_bf_declarations "${file}")
-endforeach()
-
-set(config_c_sources ${config_c_sources} CACHE INTERNAL "")
-set(config_asm_sources ${config_asm_sources} CACHE INTERNAL "")
-set(config_bf_declarations ${config_bf_declarations} CACHE INTERNAL "")
-set(config_KernelDTSList ${KernelDTSList} CACHE INTERNAL "")
-
 if("${TRIPLE}" STREQUAL "")
     set(toolchain_file gcc.cmake)
 else()
@@ -304,6 +233,10 @@ if(
     ("${CMAKE_TOOLCHAIN_FILE}" STREQUAL "")
     OR ("${CMAKE_TOOLCHAIN_FILE}" STREQUAL "${toolchain_outputfile}")
 )
+    if(DEFINED CACHE{CROSS_COMPILER_PREFIX})
+        set(cross_prefix $CACHE{CROSS_COMPILER_PREFIX})
+    endif()
+
     configure_file(
         "${CMAKE_CURRENT_LIST_DIR}/../${toolchain_file}" "${toolchain_outputfile}.temp" @ONLY
     )

gcc.cmake

@@ -19,16 +19,16 @@ set(CMAKE_STAGING_PREFIX "${CMAKE_BINARY_DIR}/staging")
 set(sel4_arch @KernelSel4Arch@)
 set(arch @KernelArch@)
 set(mode @KernelWordSize@)
-set(cross_prefix @CROSS_COMPILER_PREFIX@)
+set(cross_prefix @cross_prefix@)
 
 # If this file is used without templating, then cross_prefix will
 # have an invalid value and should only be assigned to CROSS_COMPILER_PREFIX
 # if it has been set to something different.
 # We need to build the test string dynamically otherwise the templating would
 # overwrite it.
-set(cross_prefix_test @CROSS_COMPILER_PREFIX)
+set(cross_prefix_test @cross_prefix)
 string(APPEND cross_prefix_test @)
-if(NOT "${cross_prefix}" STREQUAL "${cross_prefix_test}")
+if((NOT "${cross_prefix}" STREQUAL "${cross_prefix_test}") AND (NOT "${cross_prefix}" STREQUAL ""))
     set(CROSS_COMPILER_PREFIX ${cross_prefix})
 endif()