mmc: Set updated version to primary

Once the update is successful, mark the version as primary so that
it boots from the updated version upon BMC reboot.

Add a sleep to wait for the service file to complete setting the
primary version. Otherwise, the BMC could mark a Delete or
Priority value change as complete and the service is not done yet,
and if the BMC is rebooted it could try to boot from a non-existent
version.

As backgroung, reference issue openbmc/openbmc#2857 that attempted
to create a 'wait for service' function but was not successful.
This could be investigated further at a later time, which would
benefit other functions like Factory Reset that are also using
sleep as a workaround to wait for systemd service files.

Tested: Verified the version was set to primary during code update
        and delete, and that 3s passed (service file finished in
        about 1s) before the delete/update continued.

Change-Id: I4f9afdb020d8cc7c18cfdafe468dbff2dc8046c1
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/obmc-flash-bmc b/obmc-flash-bmc
index fec50d0..4611d91 100644
--- a/obmc-flash-bmc
+++ b/obmc-flash-bmc
@@ -447,6 +447,18 @@
 }
 
 # The eMMC partition labels for the kernel and rootfs are boot-a/b and rofs-a/b.
+# Return the label (a or b) for the running partition.
+mmc_get_primary_label() {
+  rootmatch=" on / "
+  root="$(mount -l | grep "${rootmatch}")"
+  if [[ "${root}" == *"rofs-a"* ]]; then
+    echo "a"
+  else
+    echo "b"
+  fi
+}
+
+# The eMMC partition labels for the kernel and rootfs are boot-a/b and rofs-a/b.
 # Return the label (a or b) for the non-running partition.
 mmc_get_secondary_label() {
   rootmatch=" on / "
@@ -502,6 +514,28 @@
   dd if=/dev/zero of=/dev/disk/by-partlabel/rofs-${label} count=2048
 }
 
+# Set the requested version as primary for the BMC to boot from upon reboot.
+mmc_setprimary() {
+  # Point root to the label of the requested BMC rootfs. If the label property
+  # does not exist, determine if the requested version is functional or not.
+  label=""
+  label_file="/var/lib/phosphor-bmc-code-mgmt/${version}/partlabel"
+  if [ -f "${label_file}" ]; then
+    label="$(cat "${label_file}")"
+  else
+    functional="$(busctl call xyz.openbmc_project.ObjectMapper \
+                  /xyz/openbmc_project/software/functional \
+                  org.freedesktop.DBus.Properties Get ss \
+                  xyz.openbmc_project.Association endpoints)"
+    if [[ "${functional}" =~ "${version}" ]]; then
+      label="$(mmc_get_primary_label)"
+    else
+      label="$(mmc_get_secondary_label)"
+    fi
+  fi
+  fw_setenv bootside "${label}"
+}
+
 case "$1" in
   mtduboot)
     reqmtd="$2"
@@ -574,6 +608,10 @@
     version="$2"
     mmc_remove
     ;;
+  mmc-setprimary)
+    version="$2"
+    mmc_setprimary
+    ;;
   *)
     echo "Invalid argument"
     exit 1