dtc: Flexible tree checking infrastructure (v2)

dtc: Flexible tree checking infrastructure

Here, at last, is a substantial start on revising dtc's infrastructure
for checking the tree; this is the rework I've been saying was
necessary practically since dtc was first release.

In the new model, we have a table of "check" structures, each with a
name, references to checking functions, and status variables.  Each
check can (in principle) be individually switched off or on (as either
a warning or error).  Checks have a list of prerequisites, so if
checks need to rely on results from earlier checks to make sense (or
even to avoid crashing) they just need to list the relevant other
checks there.

For now, only the "structural" checks and the fixups for phandle
references are converted to the new mechanism.  The rather more
involved semantic checks (which is where this new mechanism will
really be useful) will have to be converted in future patches.

At present, there's no user interface for turning on/off the checks -
the -f option now forces output even if "error" level checks fail.
Again, future patches will be needed to add the fine-grained control,
but that should be quite straightforward with the infrastructure
implemented here.

Also adds a testcase for the handling of bad references, which catches
a bug encountered while developing this patch.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 5 insertions, 3 deletions

diff --git a/dtc.h b/dtc.h
index d080153..ac3657b 100644
--- a/dtc.h
+++ b/dtc.h
@@ -193,9 +193,11 @@ char *get_unitname(struct node *node);
 struct property *get_property(struct node *node, char *propname);
 cell_t propval_cell(struct property *prop);
 struct node *get_subnode(struct node *node, char *nodename);
+struct node *get_node_by_path(struct node *tree, char *path);
+struct node *get_node_by_label(struct node *tree, const char *label);
 struct node *get_node_by_phandle(struct node *tree, cell_t phandle);
-
-void fixup_references(struct node *dt);
+struct node *get_node_by_ref(struct node *tree, char *ref);
+cell_t get_node_phandle(struct node *root, struct node *node);
 
 /* Boot info (tree plus memreserve information */
 
@@ -224,7 +226,7 @@ struct boot_info *build_boot_info(struct reserve_info *reservelist,
 
 /* Checks */
 
-int check_structure(struct node *dt);
+void process_checks(int force, struct node *dt);
 int check_semantics(struct node *dt, int outversion, int boot_cpuid_phys);
 
 /* Flattened trees */