Re: [PATCH v2 3/5] ArmVirtPkg/FdtClientDxe: take DT node 'status' properties into account

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 21/11/18 12:58, Ard Biesheuvel wrote:
> DT has a [pseudo-]standardized 'status' property that can be set on
> any node, and which signifies that a node should be treated as
> absent unless it is set to 'ok' or 'okay'. So take this into account
> when iterating over nodes.
> 
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> ---
>  ArmVirtPkg/FdtClientDxe/FdtClientDxe.c | 38 +++++++++++++++++---
>  1 file changed, 33 insertions(+), 5 deletions(-)
> 
> diff --git a/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c b/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c
> index fb6e0aeb9215..5bfde381ecd0 100644
> --- a/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c
> +++ b/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c
> @@ -78,6 +78,33 @@ SetNodeProperty (
>    return EFI_SUCCESS;
>  }
>  
> +STATIC
> +BOOLEAN
> +IsNodeEnabled (
> +  INT32                       Node
> +  )
> +{
> +  CONST CHAR8   *NodeStatus;
> +  INT32         Len;
> +
> +  //
> +  // A missing status property implies 'ok' so ignore any errors that
> +  // may occur here. If the status property is present, check whether
> +  // it is set to 'ok' or 'okay', anything else is treated as 'disabled'.
> +  //
> +  NodeStatus = fdt_getprop (mDeviceTreeBase, Node, "status", &Len);
> +  if (NodeStatus == NULL) {
> +    return TRUE;
> +  }
> +  if (Len >= 5 && AsciiStrCmp (NodeStatus, "okay") == 0) {
> +    return TRUE;
> +  }
> +  if (Len >= 3 && AsciiStrCmp (NodeStatus, "ok") == 0) {
> +    return TRUE;
> +  }
> +  return FALSE;
> +}
> +
>  STATIC
>  EFI_STATUS
>  EFIAPI
> @@ -101,6 +128,10 @@ FindNextCompatibleNode (
>        break;
>      }
>  
> +    if (!IsNodeEnabled (Next)) {
> +      continue;
> +    }
> +
>      Type = fdt_getprop (mDeviceTreeBase, Next, "compatible", &Len);
>      if (Type == NULL) {
>        continue;
> @@ -210,7 +241,6 @@ FindNextMemoryNodeReg (
>  {
>    INT32          Prev, Next;
>    CONST CHAR8    *DeviceType;
> -  CONST CHAR8    *NodeStatus;
>    INT32          Len;
>    EFI_STATUS     Status;
>  
> @@ -223,10 +253,8 @@ FindNextMemoryNodeReg (
>        break;
>      }
>  
> -    NodeStatus = fdt_getprop (mDeviceTreeBase, Next, "status", &Len);
> -    if (NodeStatus != NULL && AsciiStrCmp (NodeStatus, "okay") != 0) {
> -      DEBUG ((DEBUG_WARN, "%a: ignoring memory node with status \"%a\"\n",
> -        __FUNCTION__, NodeStatus));
> +    if (!IsNodeEnabled (Next)) {
> +      DEBUG ((DEBUG_WARN, "%a: ignoring disabled memory node\n", __FUNCTION__));
>        continue;
>      }
>  
>