From e4971897d7f9186446926a55255bbe27b8ea389e Mon Sep 17 00:00:00 2001
From: Patrick Urban <patrick.urban@web.de>
Date: Sat, 11 Dec 2021 16:35:30 +0100
Subject: [PATCH] jtag: ckeck highest nibble to prevent confusion between
 Cologne Chip GateMate and Efinix Trion T4/T8 devices

---
 src/jtag.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/jtag.cpp b/src/jtag.cpp
index cbfe6aa..c95577e 100644
--- a/src/jtag.cpp
+++ b/src/jtag.cpp
@@ -136,7 +136,13 @@ int Jtag::detectChain(int max_dev)
 		for (int ii=0; ii < 4; ii++)
 			tmp |= (rx_buff[ii] << (8*ii));
 		if (tmp != 0 && tmp != 0xffffffff) {
-			tmp &= 0xffffffff;
+			/* ckeck highest nibble to prevent confusion between Cologne Chip
+			 * GateMate and Efinix Trion T4/T8 devices
+			 */
+			if (tmp != 0x20000001)
+				tmp &= 0x0fffffff;
+			else
+				tmp &= 0xffffffff;
 			_devices_list.insert(_devices_list.begin(), tmp);
 
 			/* search for irlength in fpga_list or misc_dev_list */