use cat instead of tail

scripts/ci/plat/cva6/flash-firmware.sh

@@ -21,16 +21,15 @@ set -x
 ## ROM phase
 
 TTYDEV=$(find_tty 0)
-touch "$LOGFILE"
-start_record_tty "$TTYDEV" 115200 "$LOGFILE" cva6-tty
+configure_tty "$TTYDEV"
 
 # Wait for bootrom break
 power_on
-tail -f "$LOGFILE" | grep -m1 'Hit any key to enter update mode'
+cat "$TTYDEV" | grep --line-buffered -m1 'Hit any key to enter update mode'
 echo 'a' > "$TTYDEV"
 
 # Send size
-tail -f "$LOGFILE" | grep -m1 'size:'
+cat "$TTYDEV" | grep --line-buffered -m1 'size:'
 FILESIZE=$(stat --printf="%s" "$FIRMWARE_FILENAME")
 printf "0: %.8x" "$FILESIZE" | sed -E 's/0: (..)(..)(..)(..)/0: \4\3\2\1/' | xxd -r -g0 > "$TTYDEV"
 sleep 1
@@ -41,7 +40,7 @@ dd if="$FIRMWARE_FILENAME" of="$TTYDEV" bs=1 status=progress
 ## Uboot phase (TFTP)
 
 # Wait for uboot prompt and send firmware image
-tail -f "$LOGFILE" | grep -m1 "Hit any key to stop autoboot"
+cat "$TTYDEV" | grep --line-buffered -m1 "Hit any key to stop autoboot"
 echo 'a' > "$TTYDEV"
 
 rm "$TFTP_DIR/fw_payload.bin"
@@ -50,6 +49,5 @@ echo "setenv serverip $HOST_IP" > "$TTYDEV"
 echo "setenv ipaddr $BOARD_IP" > "$TTYDEV"
 echo "tftp fw_payload.bin" > "$TTYDEV"
 
-stop_record_tty
 power_off