Jetson-TX1: Add ability to mount root via NFS

Added new init script that can also mount NFS root. The original init
script from meta-tegra layer can only mount from local disk partitions,
so an enhanced version of the script was written. While primarily
written for RTA testing, end users may find the ability to mount from
NFS useful.

Task-number: QTBUG-61190
Change-Id: I76af558f2a528862ca1f88dcb4958a5686b508f5
Reviewed-by: Samuli Piippo <samuli.piippo@qt.io>

1 files changed, 44 insertions, 0 deletions

diff --git a/meta-tegra-extras/recipes/initscripts/tegra210-minimal-init/init-boot.sh b/meta-tegra-extras/recipes/initscripts/tegra210-minimal-init/init-boot.sh
new file mode 100644
index 0000000..3e43b60
--- /dev/null
+++ b/meta-tegra-extras/recipes/initscripts/tegra210-minimal-init/init-boot.sh
@@ -0,0 +1,44 @@
+#!/bin/sh
+PATH=/sbin:/bin:/usr/sbin:/usr/bin
+mount -t proc proc /proc
+mount -t devtmpfs none /dev
+mount -t sysfs sysfs /sys
+
+rootdev=""
+opt="rw"
+wait=""
+nfsroot=""
+nfsopts=""
+for bootarg in `cat /proc/cmdline`; do
+    case "$bootarg" in
+    root=*) rootdev="${bootarg##root=}" ;;
+    nfsroot=*)
+            nfsroot=$(echo ${bootarg##nfsroot=} | cut -d ',' -f 1)
+            nfsopts=$(echo ${bootarg##nfsroot=} | cut -d ',' -f 2-)
+            nfsopts=${nfsopts##${nfsroot}}
+            ;;
+    ro) opt="ro" ;;
+    rootwait) wait="yes" ;;
+    esac
+done
+if [ -n "$wait" -a ! -b "${rootdev}" ]; then
+    echo "Waiting for ${rootdev}..."
+    count=0
+    while [ $count -lt 25 ]; do
+    test -b "${rootdev}" && break
+    sleep 0.1
+    count=`expr $count + 1`
+    done
+fi
+echo "Mounting ${rootdev}..."
+if [ "$rootdev" = "/dev/nfs" ]; then
+    echo "Using NFS to boot..."
+    mount -t nfs -o "${opt},${nfsopts}" "${nfsroot}" /mnt || exec sh
+else
+    mount -t ext4 -o "$opt" "${rootdev}" /mnt || exec sh
+fi
+echo "Switching to rootfs on ${rootdev}..."
+mount --move /sys  /mnt/sys
+mount --move /proc /mnt/proc
+mount --move /dev  /mnt/dev
+exec switch_root /mnt /sbin/init