meta-ampere: Support solssh

Support solssh for Mt.Jade system.
It opens these ssh ports:
2200 - CPU console
2201 - SCP 0 concole
2202 - ATF console
2203 - SCP 1 console

Tested:
- connect to ssh ports
- make sure the console are displayed correctly

Signed-off-by: Tung Nguyen <tungnguyen@os.amperecomputing.com>
Change-Id: Ic0be980f201c0176ca00fd07804c101f404e707a
diff --git a/meta-ampere/meta-jade/recipes-phosphor/console/obmc-console/ampere_uartmux_ctrl.sh b/meta-ampere/meta-jade/recipes-phosphor/console/obmc-console/ampere_uartmux_ctrl.sh
new file mode 100755
index 0000000..58fffd8
--- /dev/null
+++ b/meta-ampere/meta-jade/recipes-phosphor/console/obmc-console/ampere_uartmux_ctrl.sh
@@ -0,0 +1,84 @@
+#!/bin/bash
+#
+# Copyright (c) 2020 Ampere Computing LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#	http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Ampere Computing LLC: UART MUX/DEMUX for CPU0 UART0,1,4 and CPU1 UART1
+# Usage: ampere_uartmux_ctrl.sh <CPU UART port number> <UARTx_MODE>
+#        <UARTx_MODE> of 1 sets CPU To HDR_CONN
+#        <UARTx_MODE> of 2 sets BMC to CPU (eg dropbear ssh server on port 2200)
+
+if [ $# -lt 2 ]; then
+	exit 1
+fi
+
+function set_gpio_active_low() {
+  if [ $# -ne 2 ]; then
+    echo "set_gpio_active_low: need both GPIO# and initial level";
+    return;
+  fi
+
+  if [ ! -d /sys/class/gpio/gpio$1 ]; then
+    echo $1 > /sys/class/gpio/export
+  fi
+  echo $2 > /sys/class/gpio/gpio$1/direction
+}
+
+GPIO_BASE=$(cat /sys/class/gpio/gpio*/base)
+
+case "$1" in
+	1) GPIO_UARTx_MODE0=56
+	   # CPU0 UART0 connects to BMC UART1
+	   CONSOLE_PORT=0
+	;;
+	2) GPIO_UARTx_MODE0=57
+	   # CPU0 UART1 connects to BMC UART2
+	   CONSOLE_PORT=1
+	;;
+	3) GPIO_UARTx_MODE0=58
+	   # CPU0 UART4 connects to BMC UART3
+	   CONSOLE_PORT=2
+	;;
+	4) GPIO_UARTx_MODE0=59
+	   # CPU1 UART1 connects to BMC UART4
+	   CONSOLE_PORT=3
+	;;
+	*) echo "Invalid UART port selection"
+	   exit 1
+	;;
+esac
+
+# Only switch the MUX when there is no active connection. This means we only
+# switch the MUX before the first session starts and after the last session
+# closes. We do this by querying number of connected sessions to the socket
+# of requested console port.
+# Example format:  Accepted: 1; Connected: 1;
+CONNECTED=$(systemctl --no-pager status obmc-console-ttyS${CONSOLE_PORT}-ssh.socket | grep -w Connected | cut -d ':' -f 3 | tr -d ' ;')
+if [ ! $CONNECTED -le 1 ]; then
+	exit 0
+fi
+
+echo "Ampere UART MUX CTRL UART port $1 to mode $2"
+
+case "$2" in
+	1) set_gpio_active_low $((${GPIO_BASE} + ${GPIO_UARTx_MODE0})) low
+	   exit 0
+	;;
+	2) set_gpio_active_low $((${GPIO_BASE} + ${GPIO_UARTx_MODE0})) high
+	   exit 0
+	;;
+	*) echo "Invalid UART mode selection"
+	   exit 1
+	;;
+esac