From 0e5e35806337933b492267d782dd39a94cac88b9 Mon Sep 17 00:00:00 2001
From: Andrei Nistor <andrei_nistor@smart-x.net>
Date: Thu, 3 Oct 2019 21:14:19 +0000
Subject: [PATCH] bootloader: make serial console configurable

Currently, the serial console is hardcoded to ttyS0 in the bootloader
element.  This is a challenge for users that want to build images for
some baremetal servers. Supermicro servers, for example, use ttyS1 for
the serial over lan interface.

This patch adds a new environment variable DIB_BOOTLOADER_SERIAL_CONSOLE
that can be set to override the default.

Change-Id: Ie8173be8690ac0b7164ce9e5b66d3c1c18f844d6
---
 diskimage_builder/elements/bootloader/README.rst            | 4 ++++
 .../bootloader/environment.d/10-bootloader-default-cmdline  | 1 +
 .../elements/bootloader/finalise.d/50-bootloader            | 6 ++++--
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/diskimage_builder/elements/bootloader/README.rst b/diskimage_builder/elements/bootloader/README.rst
index 56e17076..1c2aefc5 100644
--- a/diskimage_builder/elements/bootloader/README.rst
+++ b/diskimage_builder/elements/bootloader/README.rst
@@ -16,3 +16,7 @@ Arguments
 * ``DIB_BOOTLOADER_DEFAULT_CMDLINE`` sets parameters that are appended
   to the ``GRUB_CMDLINE_LINUX_DEFAULT`` values in ``grub.cfg``
   configuration. It defaults to ``nofb nomodeset vga=normal``.
+
+* ``DIB_BOOTLOADER_SERIAL_CONSOLE`` sets the serial device to be
+  used as a console. It defaults to ``hvc0`` for PowerPC, 
+  ``ttyAMA0,115200`` for ARM64, otherwise ``ttyS0,115200``.
diff --git a/diskimage_builder/elements/bootloader/environment.d/10-bootloader-default-cmdline b/diskimage_builder/elements/bootloader/environment.d/10-bootloader-default-cmdline
index 902494b4..2e474f92 100644
--- a/diskimage_builder/elements/bootloader/environment.d/10-bootloader-default-cmdline
+++ b/diskimage_builder/elements/bootloader/environment.d/10-bootloader-default-cmdline
@@ -1 +1,2 @@
 export DIB_BOOTLOADER_DEFAULT_CMDLINE=${DIB_BOOTLOADER_DEFAULT_CMDLINE:-"nofb nomodeset vga=normal"}
+export DIB_BOOTLOADER_SERIAL_CONSOLE=${DIB_BOOTLOADER_SERIAL_CONSOLE:-""}
\ No newline at end of file
diff --git a/diskimage_builder/elements/bootloader/finalise.d/50-bootloader b/diskimage_builder/elements/bootloader/finalise.d/50-bootloader
index 75dfd78c..26b861b8 100755
--- a/diskimage_builder/elements/bootloader/finalise.d/50-bootloader
+++ b/diskimage_builder/elements/bootloader/finalise.d/50-bootloader
@@ -174,8 +174,10 @@ function install_grub2 {
     echo 'GRUB_TERMINAL="serial console"' >>/etc/default/grub
     echo 'GRUB_GFXPAYLOAD_LINUX=auto' >>/etc/default/grub
 
-    # Serial console on Power is hvc0
-    if [[ "powerpc ppc64 ppc64le" =~ "$ARCH" ]]; then
+    if [[ -n "${DIB_BOOTLOADER_SERIAL_CONSOLE}" ]]; then
+        SERIAL_CONSOLE="${DIB_BOOTLOADER_SERIAL_CONSOLE}"
+    elif [[ "powerpc ppc64 ppc64le" =~ "$ARCH" ]]; then
+        # Serial console on Power is hvc0
         SERIAL_CONSOLE="hvc0"
     elif [[ "arm64" =~ "$ARCH" ]]; then
         SERIAL_CONSOLE="ttyAMA0,115200"