Add options for Xen and Dom0 CMD arguments

Both XEN_CMD and DOM0_CMD are optional settings  in the config file that
set Xen's and Dom0's command line arguments.  If not set, a default
value will be used.  Also, for Dom0's command line arguments, if root
isn't set in it, it will determine the best option based on the load
argument.

Signed-off-by: Brian Woods <brian.woods@xilinx.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

2 files changed, 31 insertions, 3 deletions

diff --git a/README.md b/README.md
index f688f28..8aa33a3 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,9 @@ MEMORY_END="0x80000000"
 
 DEVICE_TREE="mpsoc.dtb"
 XEN="xen"
+XEN_CMD="console=dtuart dtuart=serial0 dom0_mem=1G dom0_max_vcpus=1 bootscrub=0 vwfi=native sched=null"
 DOM0_KERNEL="Image-dom0"
+DOM0_CMD="console=hvc0 earlycon=xen earlyprintk=xen clk_ignore_unused"
 DOM0_RAMDISK="dom0-ramdisk.cpio"
 
 NUM_DOMUS=2
@@ -53,8 +55,15 @@ Where:
 - XEN specifies the Xen hypervisor binary to load. Note that it has to
   be a regular Xen binary, not a u-boot binary.
 
+- XEN_CMD specifies the command line arguments used for Xen.  If not
+  set, the default one will be used.
+
 - DOM0_KERNEL specifies the Dom0 kernel file to load.
 
+- DOM0_CMD specifies the command line arguments for Dom0's Linux
+  kernel.  If "root=" isn't set, imagebuilder will try to determine it.
+  If not set at all, the default one is used.
+
 - DOM0_RAMDISK specifies the Dom0 ramdisk to use. Note that it should be
   a regular ramdisk cpio.gz file, not a u-boot binary.
 
diff --git a/scripts/uboot-script-gen b/scripts/uboot-script-gen
index db194fe..f176e1a 100755
--- a/scripts/uboot-script-gen
+++ b/scripts/uboot-script-gen
@@ -62,13 +62,13 @@ function device_tree_editing()
     echo "fdt resize 1024" >> $UBOOT_SOURCE
     echo "fdt set /chosen \#address-cells <0x2>" >> $UBOOT_SOURCE
     echo "fdt set /chosen \#size-cells <0x2>" >> $UBOOT_SOURCE
-    echo "fdt set /chosen xen,xen-bootargs \"console=dtuart dtuart=serial0 dom0_mem=1G dom0_max_vcpus=1 bootscrub=0 vwfi=native sched=null\"" >> $UBOOT_SOURCE
+    echo "fdt set /chosen xen,xen-bootargs \"$XEN_CMD\"" >> $UBOOT_SOURCE
     echo "fdt mknod /chosen dom0" >> $UBOOT_SOURCE
     echo "fdt set /chosen/dom0 compatible \"xen,linux-zimage\" \"xen,multiboot-module\"" >> $UBOOT_SOURCE
     echo "fdt set /chosen/dom0 reg <0x0 "$dom0_kernel_addr" 0x0 "$dom0_kernel_size">" >> $UBOOT_SOURCE
     if test "$LOAD_CMD" = "tftpb"
     then
-        echo "fdt set /chosen xen,dom0-bootargs \"console=hvc0 earlycon=xen earlyprintk=xen clk_ignore_unused root=/dev/ram0\"" >> $UBOOT_SOURCE
+        echo "fdt set /chosen xen,dom0-bootargs \"$DOM0_CMD\"" >> $UBOOT_SOURCE
         if test $dom0_ramdisk_addr != "-"
         then
             echo "fdt mknod /chosen dom0-ramdisk" >> $UBOOT_SOURCE
@@ -76,7 +76,7 @@ function device_tree_editing()
             echo "fdt set /chosen/dom0-ramdisk reg <0x0 "$dom0_ramdisk_addr" 0x0 "$dom0_ramdisk_size">" >> $UBOOT_SOURCE
         fi
     else
-        echo "fdt set /chosen xen,dom0-bootargs \"console=hvc0 earlycon=xen earlyprintk=xen root=/dev/sda2\"" >> $UBOOT_SOURCE
+        echo "fdt set /chosen xen,dom0-bootargs \"$DOM0_CMD\"" >> $UBOOT_SOURCE
     fi
 
     i=0
@@ -261,6 +261,25 @@ then
     UBOOT_SOURCE="$UBOOT_SCRIPT_ARG".source
 fi
 
+if [ -z "$XEN_CMD" ]
+then
+    XEN_CMD="console=dtuart dtuart=serial0 dom0_mem=1G dom0_max_vcpus=1 bootscrub=0 vwfi=native sched=null"
+fi
+
+if [ -z "$DOM0_CMD" ]
+then
+    DOM0_CMD="console=hvc0 earlycon=xen earlyprintk=xen clk_ignore_unused"
+fi
+if [[ ! $DOM0_CMD =~ root= ]]
+then
+    if test "$LOAD_CMD" = "tftpb"
+    then
+        DOM0_CMD="$DOM0_CMD root=/dev/ram0"
+    else
+        DOM0_CMD="$DOM0_CMD root=/dev/sda2"
+    fi
+fi
+
 # the cd is needed so that the relative paths will match once we use
 # tftp or move the files to a partition
 cd "$uboot_dir"