soc/intel/denverton_ns: Enable MC Exception

Change-Id: I9773c61d06bb6c68612e498a35b5ad22cd5a8a6e
Signed-off-by: Julien Viard de Galbert <jviarddegalbert@online.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/25434
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/soc/intel/denverton_ns/cpu.c

@@ -2,6 +2,7 @@
 
 #include <console/console.h>
 #include <cpu/cpu.h>
+#include <cpu/x86/cr.h>
 #include <cpu/x86/mp.h>
 #include <cpu/x86/msr.h>
 #include <cpu/x86/mtrr.h>
@@ -44,6 +45,12 @@ static void dnv_configure_mca(void)
 	   of these banks are core vs package scope. For now every CPU clears
 	   every bank. */
 	mca_configure();
+
+	/* TODO install a fallback MC handler for each core in case OS does
+	   not provide one. Is it really needed? */
+
+	/* Enable the machine check exception */
+	write_cr4(read_cr4() | CR4_MCE);
 }
 
 static void denverton_core_init(struct device *cpu)