CMake: Add KernelHardwareDebugAPIUnsupported

There are platforms/archs that don't support the Kernel Hardware Debug
API and they can now advertise that by setting
KernelHardwareDebugAPIUnsupported.

config.cmake

@@ -320,7 +320,7 @@ config_option(
     allows userspace processes to set breakpoints, watchpoints and to \
     single-step through thread execution."
     DEFAULT OFF
-    DEPENDS "NOT KernelVerificationBuild"
+    DEPENDS "NOT KernelVerificationBuild;NOT KernelHardwareDebugAPIUnsupported"
 )
 config_option(
     KernelPrinting PRINTING

src/arch/arm/config.cmake

@@ -160,6 +160,10 @@ if(KernelAArch32FPUEnableContextSwitch OR KernelSel4ArchAarch64)
     set(KernelHaveFPU ON)
 endif()
 
+if(KernelSel4ArchAarch64)
+    set(KernelHardwareDebugAPIUnsupported ON CACHE INTERNAL "")
+endif()
+
 if(
     KernelArmCortexA7
     OR KernelArmCortexA8

src/arch/riscv/config.cmake

@@ -25,6 +25,9 @@ if(KernelSel4ArchRiscV32)
     set(KernelPTLevels 2 CACHE STRING "" FORCE)
 endif()
 
+# This is not supported on RISC-V
+set(KernelHardwareDebugAPIUnsupported ON CACHE INTERNAL "")
+
 add_sources(
     DEP "KernelArchRiscV"
     PREFIX src/arch/riscv

src/plat/am335x/config.cmake

@@ -26,6 +26,7 @@ if(KernelPlatformAM335X)
     # MCS is not supported on am335x.
     # It requires a timer driver that implements the tickless programming requirements.
     set(KernelPlatformSupportsMCS OFF)
+    set(KernelHardwareDebugAPIUnsupported ON CACHE INTERNAL "")
 
     set(KernelArmCortexA8 ON)
     set(KernelArchArmV7a ON)

src/plat/exynos5/config.cmake

@@ -67,6 +67,10 @@ if(KernelPlatExynos5)
         config_set(KernelPlatExynos54xx PLAT_EXYNOS54XX OFF)
     endif()
 
+    if(NOT KernelPlatformExynos5422)
+        set(KernelHardwareDebugAPIUnsupported ON CACHE INTERNAL "")
+    endif()
+
     list(APPEND KernelDTSList "tools/dts/${KernelARMPlatform}.dts")
     list(APPEND KernelDTSList "src/plat/exynos5/overlay-${KernelARMPlatform}.dts")
     declare_default_headers(

src/plat/imx31/config.cmake

@@ -18,6 +18,7 @@ if(KernelPlatformKZM)
     declare_seL4_arch(aarch32)
     set(KernelArm1136JF_S ON)
     set(KernelArchArmV6 ON)
+    set(KernelHardwareDebugAPIUnsupported ON CACHE INTERNAL "")
     config_set(KernelARMPlatform ARM_PLAT kzm)
     set(KernelArmMach "imx" CACHE INTERNAL "")
     list(APPEND KernelDTSList "tools/dts/kzm.dts")

src/plat/omap3/config.cmake

@@ -18,6 +18,7 @@ if(KernelPlatformOMAP3)
     declare_seL4_arch(aarch32)
     set(KernelArmCortexA8 ON)
     set(KernelArchArmV7a ON)
+    set(KernelHardwareDebugAPIUnsupported ON CACHE INTERNAL "")
     config_set(KernelARMPlatform ARM_PLAT omap3)
     config_set(KernelArmMach MACH "omap")
     list(APPEND KernelDTSList "tools/dts/omap3.dts")