Re: [ImageBuilder] [PATCH 2/2] uboot-script-gen: Enable direct mapping of statically allocated memory

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Sun, 19 Jun 2022, Xenia Ragiadakou wrote:
> Direct mapping for dom0less VMs is disabled by default in XEN and can be
> enabled through the 'direct-map' property.
> Add a new config parameter DOMU_DIRECT_MAP to be able to enable or disable
> direct mapping, i.e set to 1 for enabling and to 0 for disabling.
> This parameter is optional. Direct mapping is enabled by default for all
> dom0less VMs with static allocation.
> 
> The property 'direct-map' is a boolean property. Boolean properties are true
> if present and false if missing.
> Add a new data_type 'bool' in function dt_set() to setup a boolean property.
> 
> Signed-off-by: Xenia Ragiadakou <burzalodowa@xxxxxxxxx>

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


> ---
>  README.md                |  4 ++++
>  scripts/uboot-script-gen | 18 ++++++++++++++++++
>  2 files changed, 22 insertions(+)
> 
> diff --git a/README.md b/README.md
> index c52e4b9..17ff206 100644
> --- a/README.md
> +++ b/README.md
> @@ -168,6 +168,10 @@ Where:
>    if specified, indicates the host physical address regions
>    [baseaddr, baseaddr + size) to be reserved to the VM for static allocation.
>  
> +- DOMU_DIRECT_MAP[number] can be set to 1 or 0.
> +  If set to 1, the VM is direct mapped. The default is 1.
> +  This is only applicable when DOMU_STATIC_MEM is specified.
> +
>  - LINUX is optional but specifies the Linux kernel for when Xen is NOT
>    used.  To enable this set any LINUX\_\* variables and do NOT set the
>    XEN variable.
> diff --git a/scripts/uboot-script-gen b/scripts/uboot-script-gen
> index bdc8a6b..e85c6ec 100755
> --- a/scripts/uboot-script-gen
> +++ b/scripts/uboot-script-gen
> @@ -27,6 +27,7 @@ function dt_mknode()
>  #   hex
>  #   str
>  #   str_a
> +#   bool
>  function dt_set()
>  {
>      local path=$1
> @@ -49,6 +50,12 @@ function dt_set()
>                  array+=" \"$element\""
>              done
>              echo "fdt set $path $var $array" >> $UBOOT_SOURCE
> +        elif test $data_type = "bool"
> +        then
> +            if test "$data" -eq 1
> +            then
> +                echo "fdt set $path $var" >> $UBOOT_SOURCE
> +            fi
>          else
>              echo "fdt set $path $var \"$data\"" >> $UBOOT_SOURCE
>          fi
> @@ -65,6 +72,12 @@ function dt_set()
>          elif test $data_type = "str_a"
>          then
>              fdtput $FDTEDIT -p -t s $path $var $data
> +        elif test $data_type = "bool"
> +        then
> +            if test "$data" -eq 1
> +            then
> +                fdtput $FDTEDIT -p $path $var
> +            fi
>          else
>              fdtput $FDTEDIT -p -t s $path $var "$data"
>          fi
> @@ -206,6 +219,7 @@ function xen_device_tree_editing()
>          if test "${DOMU_STATIC_MEM[$i]}"
>          then
>              add_device_tree_static_mem "/chosen/domU$i" 
> "${DOMU_STATIC_MEM[$i]}"
> +            dt_set "/chosen/domU$i" "direct-map" "bool" 
> "${DOMU_DIRECT_MAP[$i]}"
>          fi
>          dt_set "/chosen/domU$i" "vpl011" "hex" "0x1"
>          if test "$DOM0_KERNEL"
> @@ -470,6 +484,10 @@ function xen_config()
>          then
>              DOMU_CMD[$i]="console=ttyAMA0"
>          fi
> +        if test -z "${DOMU_DIRECT_MAP[$i]}"
> +        then
> +             DOMU_DIRECT_MAP[$i]=1
> +        fi
>          i=$(( $i + 1 ))
>      done
>  }
> -- 
> 2.34.1
>