diff --git a/doc/openocd.texi b/doc/openocd.texi
index f4408fa23..22c7fcedd 100644
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -2561,6 +2561,32 @@ and a specific set of GPIOs is used.
 @deffn {Interface Driver} {ch347}
 Driver for WCH CH347F and CH347T chips.
 When using the CH347T, it must be configured to operate in mode 3 (UART + JTAG).
+
+@b{WARNING:} WCH CH347T chips have rather poor performance
+with respect to the USB HS connection. Upgrade firmware to the latest version!
+@itemize @bullet
+@item Chip version 2.41:
+@itemize @minus
+@item JTAG timing is very weird, some clock pulses are
+much shorter then the requested clock frequency.
+@item SWD is not implemented.
+@end itemize
+@item Chip version 4.41:
+@itemize @minus
+@item SWD clock is limited to 1 MHz maximum.
+@item SWD reading AP reg CH347 erroneously drives
+SWDIO to H for 392 ns after the last ACK bit. Some devices get so upset
+that send wrong data with parity error. A resistor in the SWDIO circuit
+mitigates the problem.
+@item A long SWD operation causes that USB host disconnects the adapter.
+@end itemize
+@item Chip version 5.44:
+@itemize @minus
+@item Maximal SWD clock speed is 5 MHz
+@item A long SWD operation causes that USB host disconnects the adapter.
+@end itemize
+@end itemize
+
 This driver has these driver-specific command:
 
 @deffn {Config Command} {ch347 vid_pid} [vid pid]+
diff --git a/src/jtag/drivers/ch347.c b/src/jtag/drivers/ch347.c
index 41893d144..8c9c784cd 100644
--- a/src/jtag/drivers/ch347.c
+++ b/src/jtag/drivers/ch347.c
@@ -1402,13 +1402,34 @@ static int ch347_open_device(void)
 		firmware_version);
 
 	if (ch347.chip_variant == CH347T && ch347_device_descriptor.bcdDevice < BYTEWISE_MODE_VERSION) {
-		LOG_INFO("CH347 old version of the chip, JTAG only working in bitwise mode. For bytewise mode at least version %X.%X is needed.",
+		LOG_INFO("CH347T old version of the chip, JTAG only working in bitwise mode. For bytewise mode at least version %X.%X is needed.",
 			(BYTEWISE_MODE_VERSION >> 8) & 0xFF,
 			BYTEWISE_MODE_VERSION & 0xFF);
 		ch347.use_bitwise_mode = true;
 	} else {
 		ch347.use_bitwise_mode = false;
 	}
+
+	if (ch347.chip_variant == CH347T) {
+		if (swd_mode) {
+			if (ch347_device_descriptor.bcdDevice < 0x441)
+				LOG_WARNING("CH347T version older than 4.41 probably does not support SWD transport");
+
+			if (ch347_device_descriptor.bcdDevice == 0x441)
+				LOG_WARNING("If CH347T version 4.41 cannot connect or SWD fails often, insert a resistor to SWDIO circuit");
+
+		} else if (ch347_device_descriptor.bcdDevice == 0x241) {
+			LOG_WARNING("CH347T version 2.41 has very weird clock timing, may not work with a slower JTAG device");
+		}
+
+		if (ch347_device_descriptor.bcdDevice < 0x544)
+			LOG_INFO("Please upgrade CH347T firmware to a production version >= 5.44");
+
+	} else if (ch347.chip_variant == CH347F) {
+		if (ch347_device_descriptor.bcdDevice < 0x101)
+			LOG_INFO("Please upgrade CH347F firmware to a production version >= 1.1");
+	}
+
 	return ERROR_OK;
 }