x86: x86_64 can only support max 4 CPUs

With all the stacks and TSS (etc), the x86_64 arch code can only support maximum of 4 CPUs at the moment. So add a build assert if more CPUs are specified via CONFIG_MP_MAX_NUM_CPUS, also overwrite the range value for CONFIG_MP_MAX_NUM_CPUS. Signed-off-by: Daniel Leung <daniel.leung@intel.com>
tobias-roehmel · Jun 17, 2023 · ad826f3 · ad826f3
1 parent 5bd42b9
commit ad826f3
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diff --git a/arch/x86/core/Kconfig.intel64 b/arch/x86/core/Kconfig.intel64
@@ -87,4 +87,7 @@ config X86_USERSPACE
 	 supporting user-level threads that are protected from each other and
 	 from crashing the kernel.
 
+config MP_MAX_NUM_CPUS
+	range 1 4
+
 endif # X86_64
diff --git a/arch/x86/core/intel64/cpu.c b/arch/x86/core/intel64/cpu.c
@@ -13,6 +13,8 @@
 #include <zephyr/drivers/interrupt_controller/loapic.h>
 #include <zephyr/arch/x86/acpi.h>
 
+BUILD_ASSERT(CONFIG_MP_MAX_NUM_CPUS <= 4, "Only supports max 4 CPUs");
+
 /*
  * Map of CPU logical IDs to CPU local APIC IDs. By default,
  * we assume this simple identity mapping, as found in QEMU.