fdtgrep: Cope with the /aliases node being last
With skeleton.dtsi being dropped it is more likely that the /aliases node
will be last in the device tree. Update fdtgrep to handle this.
Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/lib/libfdt/fdt_region.c b/lib/libfdt/fdt_region.c
index d2ce4c1..8b8a547 100644
--- a/lib/libfdt/fdt_region.c
+++ b/lib/libfdt/fdt_region.c
@@ -63,6 +63,30 @@
return 0;
}
+/**
+ * fdt_add_alias_regions() - Add regions covering the aliases that we want
+ *
+ * The /aliases node is not automatically included by fdtgrep unless the
+ * command-line arguments cause to be included (or not excluded). However
+ * aliases are special in that we generally want to include those which
+ * reference a node that fdtgrep includes.
+ *
+ * In fact we want to include only aliases for those nodes still included in
+ * the fdt, and drop the other aliases since they point to nodes that will not
+ * be present.
+ *
+ * This function scans the aliases and adds regions for those which we want
+ * to keep.
+ *
+ * @fdt: Device tree to scan
+ * @region: List of regions
+ * @count: Number of regions in the list so far (i.e. starting point for this
+ * function)
+ * @max_regions: Maximum number of regions in @region list
+ * @info: Place to put the region state
+ * @return number of regions after processing, or -FDT_ERR_NOSPACE if we did
+ * not have enough room in the regions table for the regions we wanted to add.
+ */
int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count,
int max_regions, struct fdt_region_state *info)
{
@@ -74,11 +98,17 @@
if (node < 0)
return -FDT_ERR_NOTFOUND;
- /* The aliases node must come before the others */
+ /*
+ * Find the next node so that we know where the /aliases node ends. We
+ * need special handling if /aliases is the last node.
+ */
node_end = fdt_next_subnode(fdt, node);
- if (node_end <= 0)
- return -FDT_ERR_BADLAYOUT;
- node_end -= sizeof(fdt32_t);
+ if (node_end == -FDT_ERR_NOTFOUND)
+ /* Move back to the FDT_END_NODE tag of '/' */
+ node_end = fdt_size_dt_struct(fdt) - sizeof(fdt32_t) * 2;
+ else if (node_end < 0) /* other error */
+ return node_end;
+ node_end -= sizeof(fdt32_t); /* Move to FDT_END_NODE tag of /aliases */
did_alias_header = 0;
info->region = region;
@@ -109,7 +139,7 @@
fdt_add_region(info, base + offset, next - offset);
}
- /* Add the 'end' tag */
+ /* Add the FDT_END_NODE tag */
if (did_alias_header)
fdt_add_region(info, base + node_end, sizeof(fdt32_t));
diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c
index b907827..e373c43 100644
--- a/tools/fdtgrep.c
+++ b/tools/fdtgrep.c
@@ -810,9 +810,6 @@
disp->flags);
if (count < 0) {
report_error("fdt_find_regions", count);
- if (count == -FDT_ERR_BADLAYOUT)
- fprintf(stderr,
- "/aliases node must come before all other nodes\n");
return -1;
}
if (count <= max_regions)