diff --git a/tools/amldecode/aml/opcode.c b/tools/amldecode/aml/opcode.c
index 54c6e1b..7132d91 100644
--- a/tools/amldecode/aml/opcode.c
+++ b/tools/amldecode/aml/opcode.c
@@ -22,32 +22,42 @@ static int32_t read_pkg_length(struct aml_parser *parser)
 	}
 
 	int32_t len = 0;
-	int32_t tmp = 0;
+	int32_t p1 = 0, p2 = 0, p3 = 0;
 
 	int nbytes = (p0 & 0xC0) >> 6;
 	switch (nbytes) {
 	case 3:
-		tmp = aml_parser_advance(parser);
-		if (tmp == PARSE_EOF) {
+		p1 = aml_parser_advance(parser);
+		p2 = aml_parser_advance(parser);
+		p3 = aml_parser_advance(parser);
+		if (p3 == PARSE_EOF) {
 			return PARSE_EOF;
 		}
 
-		len |= tmp << 20;
+		len = p0 & 0x0F;
+		len |= p1 << 4;
+		len |= p2 << 12;
+		len |= p3 << 20;
+		break;
 	case 2:
-		tmp = aml_parser_advance(parser);
-		if (tmp == PARSE_EOF) {
+		p1 = aml_parser_advance(parser);
+		p2 = aml_parser_advance(parser);
+		if (p2 == PARSE_EOF) {
 			return PARSE_EOF;
 		}
 
-		len |= tmp << 12;
+		len = p0 & 0x0F;
+		len |= p1 << 4;
+		len |= p2 << 12;
+		break;
 	case 1:
-		len |= p0 & 0x0F;
-		tmp = aml_parser_advance(parser);
-		if (tmp == PARSE_EOF) {
+		p1 = aml_parser_advance(parser);
+		if (p1 == PARSE_EOF) {
 			return PARSE_EOF;
 		}
 
-		len |= tmp << 4;
+		len = p0 & 0x0F;
+		len |= p1 << 4;
 		break;
 	case 0:
 		len = p0 & 0x3F;