diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index 11094d857b92..5ba268266d16 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -86,6 +86,7 @@
 #define CP0_XCONTEXT $20
 #define CP0_FRAMEMASK $21
 #define CP0_DIAGNOSTIC $22
+#define CP0_DIAGNOSTIC1 $22, 1
 #define CP0_DEBUG $23
 #define CP0_DEPC $24
 #define CP0_PERFORMANCE $25
@@ -1051,6 +1052,13 @@
 /* Flush FTLB */
 #define LOONGSON_DIAG_FTLB	(_ULCAST_(1) << 13)
 
+/*
+ * Diag1 (GSCause in Loongson-speak) fields
+ */
+/* Loongson-specific exception code (GSExcCode) */
+#define LOONGSON_DIAG1_EXCCODE_SHIFT	2
+#define LOONGSON_DIAG1_EXCCODE		GENMASK(6, 2)
+
 /* CvmCtl register field definitions */
 #define CVMCTL_IPPCI_SHIFT	7
 #define CVMCTL_IPPCI		(_U64CAST_(0x7) << CVMCTL_IPPCI_SHIFT)