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>
This commit is contained in:
Simon Glass 2017-04-02 12:26:44 -06:00
parent f156b5b597
commit c47a38b477
2 changed files with 35 additions and 8 deletions

View file

@ -63,6 +63,30 @@ static int region_list_contains_offset(struct fdt_region_state *info,
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 @@ int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count,
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 @@ int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count,
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));

View file

@ -810,9 +810,6 @@ static int do_fdtgrep(struct display_info *disp, const char *filename)
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)