Enable the generation of symbols & local fixup information
for trees compiled with the -@ (--symbols) option.
Using this patch labels in the tree and their users emit information
in __symbols__ and __local_fixups__ nodes. Using this information
it is possible to implement run time dynamic tree loading.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
---
Documentation/manual.txt | 5 ++
checks.c | 61 +++++++++++++++++++++
dtc.c | 9 ++-
dtc.h | 28 ++++++++++
flattree.c | 139 +++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 240 insertions(+), 2 deletions(-)
diff --git a/Documentation/manual.txt b/Documentation/manual.txt
index 398de32..4359958 100644
--- a/Documentation/manual.txt
+++ b/Documentation/manual.txt
@@ -119,6 +119,11 @@ Options:
Make space for <number> reserve map entries
Relevant for dtb and asm output only.
+ -@
+ Generates a __symbols__ node at the root node of the resulting blob
+ for any node labels used, and for any local references using phandles
+ it also generates a __local_fixups__ node that tracks them.
+
-S <bytes>
Ensure the blob at least <bytes> long, adding additional
space if needed.
diff --git a/checks.c b/checks.c
index e81a8c7..103ca52 100644
--- a/checks.c
+++ b/checks.c
@@ -458,6 +458,7 @@ static void fixup_phandle_references(struct check *c, struct node *dt,
struct node *node, struct property *prop)
{
struct marker *m = prop->val.markers;
+ struct fixup_entry *fe, **fep;
struct node *refnode;
cell_t phandle;
@@ -471,9 +472,28 @@ static void fixup_phandle_references(struct check *c, struct node *dt,
continue;
}
+ /* if it's a local reference, we need to record it */
+ if (symbol_fixup_support) {
+
+ /* allocate a new local fixup entry */
+ fe = xmalloc(sizeof(*fe));
+
+ fe->node = node;
+ fe->prop = prop;
+ fe->offset = m->offset;
+ fe->next = NULL;
+
+ /* append it to the local fixups */
+ fep = &dt->local_fixups;
+ while (*fep)
+ fep = &(*fep)->next;
+ *fep = fe;
+ }
+
phandle = get_node_phandle(dt, refnode);
*((cell_t *)(prop->val.val + m->offset)) = cpu_to_fdt32(phandle);
}
+
}
ERROR(phandle_references, NULL, NULL, fixup_phandle_references, NULL,
&duplicate_node_names, &explicit_phandles);
@@ -652,6 +672,45 @@ static void check_obsolete_chosen_interrupt_controller(struct check *c,
}
TREE_WARNING(obsolete_chosen_interrupt_controller, NULL);
+static void check_auto_label_phandles(struct check *c, struct node *dt,
+ struct node *node)
+{
+ struct label *l;
+ struct symbol *s, **sp;
+ int has_label;
+
+ if (!symbol_fixup_support)
+ return;
+
+ has_label = 0;
+ for_each_label(node->labels, l) {
+ has_label = 1;
+ break;
+ }
+
+ if (!has_label)
+ return;
+
+ /* force allocation of a phandle for this node */
+ (void)get_node_phandle(dt, node);
+
+ /* add the symbol */
+ for_each_label(node->labels, l) {
+
+ s = xmalloc(sizeof(*s));
+ s->label = l;
+ s->node = node;
+ s->next = NULL;
+
+ /* add it to the symbols list */
+ sp = &dt->symbols;
+ while (*sp)
+ sp = &((*sp)->next);
+ *sp = s;
+ }
+}
+NODE_WARNING(auto_label_phandles, NULL);
+
static struct check *check_table[] = {
&duplicate_node_names, &duplicate_property_names,
&node_name_chars, &node_name_format, &property_name_chars,
@@ -670,6 +729,8 @@ static struct check *check_table[] = {
&avoid_default_addr_size,
&obsolete_chosen_interrupt_controller,
+ &auto_label_phandles,
+
&always_fail,
};
diff --git a/dtc.c b/dtc.c
index 8c4add6..91e91e7 100644
--- a/dtc.c
+++ b/dtc.c
@@ -29,6 +29,7 @@ int reservenum; /* Number of memory reservation slots */
int minsize; /* Minimum blob size */
int padsize; /* Additional padding to blob */
int phandle_format = PHANDLE_BOTH; /* Use linux,phandle or phandle properties */
+int symbol_fixup_support = 0;
static void fill_fullpaths(struct node *tree, const char *prefix)
{
@@ -51,7 +52,7 @@ static void fill_fullpaths(struct node *tree, const char *prefix)
#define FDT_VERSION(version) _FDT_VERSION(version)
#define _FDT_VERSION(version) #version
static const char usage_synopsis[] = "dtc [options] <input file>";
-static const char usage_short_opts[] = "qI:O:o:V:d:R:S:p:fb:i:H:sW:E:hv";
+static const char usage_short_opts[] = "qI:O:o:V:d:R:S:p:fb:i:H:sW:E:@hv";
static struct option const usage_long_opts[] = {
{"quiet", no_argument, NULL, 'q'},
{"in-format", a_argument, NULL, 'I'},
@@ -69,6 +70,7 @@ static struct option const usage_long_opts[] = {
{"phandle", a_argument, NULL, 'H'},
{"warning", a_argument, NULL, 'W'},
{"error", a_argument, NULL, 'E'},
+ {"symbols", no_argument, NULL, '@'},
{"help", no_argument, NULL, 'h'},
{"version", no_argument, NULL, 'v'},
{NULL, no_argument, NULL, 0x0},
@@ -99,6 +101,7 @@ static const char * const usage_opts_help[] = {
"\t\tboth - Both \"linux,phandle\" and \"phandle\" properties",
"\n\tEnable/disable warnings (prefix with \"no-\")",
"\n\tEnable/disable errors (prefix with \"no-\")",
+ "\n\tEnable symbols/fixup support",
"\n\tPrint this help and exit",
"\n\tPrint version and exit",
NULL,
@@ -186,7 +189,9 @@ int main(int argc, char *argv[])
case 'E':
parse_checks_option(false, true, optarg);
break;
-
+ case '@':
+ symbol_fixup_support = 1;
+ break;
case 'h':
usage(NULL);
default:
diff --git a/dtc.h b/dtc.h
index 56212c8..16354fa 100644
--- a/dtc.h
+++ b/dtc.h
@@ -54,6 +54,7 @@ extern int reservenum; /* Number of memory reservation slots */
extern int minsize; /* Minimum blob size */
extern int padsize; /* Additional padding to blob */
extern int phandle_format; /* Use linux,phandle or phandle properties */
+extern int symbol_fixup_support;/* enable symbols & fixup support */
#define PHANDLE_LEGACY 0x1
#define PHANDLE_EPAPR 0x2
@@ -132,6 +133,20 @@ struct label {
struct label *next;
};
+struct fixup_entry {
+ int offset;
+ struct node *node;
+ struct property *prop;
+ struct fixup_entry *next;
+ bool local_fixup_generated;
+};
+
+struct symbol {
+ struct label *label;
+ struct node *node;
+ struct symbol *next;
+};
+
struct property {
bool deleted;
char *name;
@@ -158,6 +173,10 @@ struct node {
int addr_cells, size_cells;
struct label *labels;
+
+ struct symbol *symbols;
+ struct fixup_entry *local_fixups;
+ bool emit_local_fixup_node;
};
#define for_each_label_withdel(l0, l) \
@@ -181,6 +200,15 @@ struct node {
for_each_child_withdel(n, c) \
if (!(c)->deleted)
+#define for_each_fixup_entry(f, fe) \
+ for ((fe) = (f)->entries; (fe); (fe) = (fe)->next)
+
+#define for_each_symbol(n, s) \
+ for ((s) = (n)->symbols; (s); (s) = (s)->next)
+
+#define for_each_local_fixup_entry(n, fe) \
+ for ((fe) = (n)->local_fixups; (fe); (fe) = (fe)->next)
+
void add_label(struct label **labels, char *label);
void delete_labels(struct label **labels);
diff --git a/flattree.c b/flattree.c
index bd99fa2..3a58949 100644
--- a/flattree.c
+++ b/flattree.c
@@ -255,6 +255,142 @@ static int stringtable_insert(struct data *d, const char *str)
return i;
}
+static void emit_local_fixups(struct node *tree, struct emitter *emit,
+ void *etarget, struct data *strbuf, struct version_info *vi,
+ struct node *node)
+{
+ struct fixup_entry *fe, *fen;
+ struct node *child;
+ int nameoff, count;
+ cell_t *buf;
+ struct data d;
+
+ if (node->emit_local_fixup_node) {
+
+ /* emit the external fixups (do not emit /) */
+ if (node != tree) {
+ emit->beginnode(etarget, NULL);
+ emit->string(etarget, node->name, 0);
+ emit->align(etarget, sizeof(cell_t));
+ }
+
+ for_each_local_fixup_entry(tree, fe) {
+ if (fe->node != node || fe->local_fixup_generated)
+ continue;
+
+ /* count the number of fixup entries */
+ count = 0;
+ for_each_local_fixup_entry(tree, fen) {
+ if (fen->prop != fe->prop)
+ continue;
+ fen->local_fixup_generated = true;
+ count++;
+ }
+
+ /* allocate buffer */
+ buf = xmalloc(count * sizeof(cell_t));
+
+ /* collect all the offsets in buffer */
+ count = 0;
+ for_each_local_fixup_entry(tree, fen) {
+ if (fen->prop != fe->prop)
+ continue;
+ fen->local_fixup_generated = true;
+ buf[count++] = cpu_to_fdt32(fen->offset);
+ }
+ d = empty_data;
+ d.len = count * sizeof(cell_t);
+ d.val = (char *)buf;
+
+ nameoff = stringtable_insert(strbuf, fe->prop->name);
+ emit->property(etarget, fe->prop->labels);
+ emit->cell(etarget, count * sizeof(cell_t));
+ emit->cell(etarget, nameoff);
+
+ if ((vi->flags & FTF_VARALIGN) &&
+ (count * sizeof(cell_t)) >= 8)
+ emit->align(etarget, 8);
+
+ emit->data(etarget, d);
+ emit->align(etarget, sizeof(cell_t));
+
+ free(buf);
+ }
+ }
+
+ for_each_child(node, child)
+ emit_local_fixups(tree, emit, etarget, strbuf, vi, child);
+
+ if (node->emit_local_fixup_node && node != tree)
+ emit->endnode(etarget, tree->labels);
+}
+
+static void emit_symbols_node(struct node *tree, struct emitter *emit,
+ void *etarget, struct data *strbuf,
+ struct version_info *vi)
+{
+ struct symbol *sym;
+ int nameoff, vallen;
+
+ /* do nothing if no symbols */
+ if (!tree->symbols)
+ return;
+
+ emit->beginnode(etarget, NULL);
+ emit->string(etarget, "__symbols__", 0);
+ emit->align(etarget, sizeof(cell_t));
+
+ for_each_symbol(tree, sym) {
+
+ vallen = strlen(sym->node->fullpath);
+
+ nameoff = stringtable_insert(strbuf, sym->label->label);
+
+ emit->property(etarget, NULL);
+ emit->cell(etarget, vallen + 1);
+ emit->cell(etarget, nameoff);
+
+ if ((vi->flags & FTF_VARALIGN) && vallen >= 8)
+ emit->align(etarget, 8);
+
+ emit->string(etarget, sym->node->fullpath,
+ strlen(sym->node->fullpath));
+ emit->align(etarget, sizeof(cell_t));
+ }
+
+ emit->endnode(etarget, NULL);
+}
+
+static void emit_local_fixups_node(struct node *tree, struct emitter *emit,
+ void *etarget, struct data *strbuf,
+ struct version_info *vi)
+{
+ struct fixup_entry *fe;
+ struct node *node;
+
+ /* do nothing if no local fixups */
+ if (!tree->local_fixups)
+ return;
+
+ /* mark all nodes that need a local fixup generated (and parents) */
+ for_each_local_fixup_entry(tree, fe) {
+ node = fe->node;
+ while (node != NULL && !node->emit_local_fixup_node) {
+ node->emit_local_fixup_node = true;
+ node = node->parent;
+ }
+ }
+
+ /* emit the local fixups node now */
+ emit->beginnode(etarget, NULL);
+ emit->string(etarget, "__local_fixups__", 0);
+ emit->align(etarget, sizeof(cell_t));
+
+ emit_local_fixups(tree, emit, etarget, strbuf, vi, tree);
+
+ emit->endnode(etarget, tree->labels);
+}
+
static void flatten_tree(struct node *tree, struct emitter *emit,
void *etarget, struct data *strbuf,
struct version_info *vi)
@@ -310,6 +446,9 @@ static void flatten_tree(struct node *tree, struct emitter *emit,
flatten_tree(child, emit, etarget, strbuf, vi);
}
+ emit_symbols_node(tree, emit, etarget, strbuf, vi);
+ emit_local_fixups_node(tree, emit, etarget, strbuf, vi);
+
emit->endnode(etarget, tree->labels);
}
--
1.7.12
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