From c47a38b47770887dc9416382207364fb62899fc2 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sun, 2 Apr 2017 12:26:44 -0600 Subject: [PATCH] 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 Tested-by: Masahiro Yamada --- lib/libfdt/fdt_region.c | 40 +++++++++++++++++++++++++++++++++++----- tools/fdtgrep.c | 3 --- 2 files changed, 35 insertions(+), 8 deletions(-) diff --git a/lib/libfdt/fdt_region.c b/lib/libfdt/fdt_region.c index d2ce4c1c53..8b8a547555 100644 --- a/lib/libfdt/fdt_region.c +++ b/lib/libfdt/fdt_region.c @@ -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)); diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c index b9078273c9..e373c43e36 100644 --- a/tools/fdtgrep.c +++ b/tools/fdtgrep.c @@ -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) -- 2.39.5