Update feature.c for C925,C930

Author: gamber27

feature.c

@@ -255,6 +255,24 @@ void setup_features(void)
 			while(1);
 		}
 		break;
+	case 0x7:
+		if (cpu_ver >= 0x0) {
+			csr_clear(CSR_MXSTATUS, 0x1);
+			csr_write(CSR_MISELECT,CSR_MNASTATUS);
+			csr_write(CSR_MIREG,0x1e);
+		} else {
+			while(1);
+		}
+		break;
+	case 0x8: 
+		if (cpu_ver >= 0x0) {
+			csr_clear(CSR_MXSTATUS, 0x1);
+			csr_write(CSR_MISELECT,CSR_MNASTATUS);
+			csr_write(CSR_MIREG,0x1e);
+		} else {
+			while(1);
+		}
+		break;
 	default:
 		while(1);
 	}

riscv_encoding.h

@@ -14,6 +14,7 @@
 #define CSR_MRVBR        0x7c7
 #define CSR_MCOUNTERWEN  0x7c9
 #define CSR_MSMPR	 0x7f3
+#define CSR_MNASTATUS   0x8000000000000210
 
 /* clang-format off */
 #define MSTATUS_SIE			_UL(0x00000002)
@@ -248,6 +249,8 @@
 #define CSR_MIP				0x344
 #define CSR_MTINST			0x34a
 #define CSR_MTVAL2			0x34b
+#define CSR_MISELECT    	0x350
+#define CSR_MIREG       	0x351
 #define CSR_PMPCFG0			0x3a0
 #define CSR_PMPCFG1			0x3a1
 #define CSR_PMPCFG2			0x3a2