Enables the generation of a __fixups__ node for trees compiled
using the -@ option that are using the /plugin/ tag.
The __fixups__ node make possible the dynamic resolution of phandle
references which are present in the plugin tree but lie in the
tree that are applying the overlay against.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
---
Documentation/manual.txt | 5 ++++
checks.c | 45 ++++++++++++++++++++++++++++++++--
dtc-lexer.l | 5 ++++
dtc-parser.y | 22 ++++++++++++++---
dtc.h | 12 +++++++++
flattree.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 147 insertions(+), 5 deletions(-)
diff --git a/Documentation/manual.txt b/Documentation/manual.txt
index 4359958..18d1333 100644
--- a/Documentation/manual.txt
+++ b/Documentation/manual.txt
@@ -124,6 +124,9 @@ Options:
for any node labels used, and for any local references using phandles
it also generates a __local_fixups__ node that tracks them.
+ When using the /plugin/ tag all unresolved label references to
+ be tracked in the __fixups__ node, making dynamic resolution possible.
+
-S <bytes>
Ensure the blob at least <bytes> long, adding additional
space if needed.
@@ -158,6 +161,8 @@ Here is a very rough overview of the layout of a DTS source file:
devicetree: '/' nodedef
+ plugindecl: '/' 'plugin' '/' ';'
+
nodedef: '{' list_of_property list_of_subnode '}' ';'
property: label PROPNAME '=' propdata ';'
diff --git a/checks.c b/checks.c
index 9361bca..59d46bc 100644
--- a/checks.c
+++ b/checks.c
@@ -457,6 +457,7 @@ 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 *f, **fp;
struct fixup_entry *fe, **fep;
struct node *refnode;
cell_t phandle;
@@ -466,8 +467,48 @@ static void fixup_phandle_references(struct check *c, struct node *dt,
refnode = get_node_by_ref(dt, m->ref);
if (! refnode) {
- FAIL(c, "Reference to non-existent node or label \"%s\"\n",
- m->ref);
+ if (!dt->is_plugin) {
+ FAIL(c, "Reference to non-existent node or label \"%s\"\n",
+ m->ref);
+ continue;
+ }
+
+ /* allocate fixup entry */
+ fe = xmalloc(sizeof(*fe));
+
+ fe->node = node;
+ fe->prop = prop;
+ fe->offset = m->offset;
+ fe->next = NULL;
+
+ /* search for an already existing fixup */
+ for_each_fixup(dt, f)
+ if (strcmp(f->ref, m->ref) == 0)
+ break;
+
+ /* no fixup found, add new */
+ if (f == NULL) {
+ f = xmalloc(sizeof(*f));
+ f->ref = m->ref;
+ f->entries = NULL;
+ f->next = NULL;
+
+ /* add it to the tree */
+ fp = &dt->fixups;
+ while (*fp)
+ fp = &(*fp)->next;
+ *fp = f;
+ }
+
+ /* and now append fixup entry */
+ fep = &f->entries;
+ while (*fep)
+ fep = &(*fep)->next;
+ *fep = fe;
+
+ /* mark the entry as unresolved */
+ *((cell_t *)(prop->val.val + m->offset)) =
+ cpu_to_fdt32(0xdeadbeef);
continue;
}
diff --git a/dtc-lexer.l b/dtc-lexer.l
index 0ee1caf..dd44ba2 100644
--- a/dtc-lexer.l
+++ b/dtc-lexer.l
@@ -113,6 +113,11 @@ static void lexical_error(const char *fmt, ...);
return DT_V1;
}
+<*>"/plugin/" {
+ DPRINT("Keyword: /plugin/\n");
+ return DT_PLUGIN;
+ }
+
<*>"/memreserve/" {
DPRINT("Keyword: /memreserve/\n");
BEGIN_DEFAULT();
diff --git a/dtc-parser.y b/dtc-parser.y
index ea57e0a..776fdd5 100644
--- a/dtc-parser.y
+++ b/dtc-parser.y
@@ -19,6 +19,7 @@
*/
%{
#include <stdio.h>
+#include <inttypes.h>
#include "dtc.h"
#include "srcpos.h"
@@ -52,9 +53,11 @@ extern bool treesource_error;
struct node *nodelist;
struct reserve_info *re;
uint64_t integer;
+ bool is_plugin;
}
%token DT_V1
+%token DT_PLUGIN
%token DT_MEMRESERVE
%token DT_LSHIFT DT_RSHIFT DT_LE DT_GE DT_EQ DT_NE DT_AND DT_OR
%token DT_BITS
@@ -71,6 +74,7 @@ extern bool treesource_error;
%type <data> propdata
%type <data> propdataprefix
+%type <is_plugin> plugindecl
%type <re> memreserve
%type <re> memreserves
%type <array> arrayprefix
@@ -101,10 +105,22 @@ extern bool treesource_error;
%%
sourcefile:
- DT_V1 ';' memreserves devicetree
+ DT_V1 ';' plugindecl memreserves devicetree
{
- the_boot_info = build_boot_info($3, $4,
- guess_boot_cpuid($4));
+ $5->is_plugin = $3;
+ the_boot_info = build_boot_info($4, $5,
+ guess_boot_cpuid($5));
+ }
+ ;
+
+plugindecl:
+ /* empty */
+ {
+ $$ = false;
+ }
+ | DT_PLUGIN ';'
+ {
+ $$ = true;
}
;
diff --git a/dtc.h b/dtc.h
index 16354fa..f163b22 100644
--- a/dtc.h
+++ b/dtc.h
@@ -141,6 +141,12 @@ struct fixup_entry {
bool local_fixup_generated;
};
+struct fixup {
+ char *ref;
+ struct fixup_entry *entries;
+ struct fixup *next;
+};
+
struct symbol {
struct label *label;
struct node *node;
@@ -177,6 +183,9 @@ struct node {
struct symbol *symbols;
struct fixup_entry *local_fixups;
bool emit_local_fixup_node;
+
+ bool is_plugin;
+ struct fixup *fixups;
};
#define for_each_label_withdel(l0, l) \
@@ -200,6 +209,9 @@ struct node {
for_each_child_withdel(n, c) \
if (!(c)->deleted)
+#define for_each_fixup(n, f) \
+ for ((f) = (n)->fixups; (f); (f) = (f)->next)
+
#define for_each_fixup_entry(f, fe) \
for ((fe) = (f)->entries; (fe); (fe) = (fe)->next)
diff --git a/flattree.c b/flattree.c
index 3a58949..2385137 100644
--- a/flattree.c
+++ b/flattree.c
@@ -391,6 +391,68 @@ static void emit_local_fixups_node(struct node *tree, struct emitter *emit,
emit->endnode(etarget, tree->labels);
}
+static void emit_fixups_node(struct node *tree, struct emitter *emit,
+ void *etarget, struct data *strbuf,
+ struct version_info *vi)
+{
+ struct fixup *f;
+ struct fixup_entry *fe;
+ char *name, *s;
+ const char *fullpath;
+ int namesz, nameoff, vallen;
+
+ /* do nothing if no fixups */
+ if (!tree->fixups)
+ return;
+
+ /* emit the external fixups */
+ emit->beginnode(etarget, NULL);
+ emit->string(etarget, "__fixups__", 0);
+ emit->align(etarget, sizeof(cell_t));
+
+ for_each_fixup(tree, f) {
+
+ namesz = 0;
+ for_each_fixup_entry(f, fe) {
+ fullpath = fe->node->fullpath;
+ if (fullpath[0] == '\0')
+ fullpath = "/";
+ namesz += strlen(fullpath) + 1;
+ namesz += strlen(fe->prop->name) + 1;
+ namesz += 32; /* space for :<number> + '\0' */
+ }
+
+ name = xmalloc(namesz);
+
+ s = name;
+ for_each_fixup_entry(f, fe) {
+ fullpath = fe->node->fullpath;
+ if (fullpath[0] == '\0')
+ fullpath = "/";
+ snprintf(s, name + namesz - s, "%s:%s:%d", fullpath,
+ fe->prop->name, fe->offset);
+ s += strlen(s) + 1;
+ }
+
+ nameoff = stringtable_insert(strbuf, f->ref);
+ vallen = s - name - 1;
+
+ 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, name, vallen);
+ emit->align(etarget, sizeof(cell_t));
+
+ free(name);
+ }
+
+ emit->endnode(etarget, tree->labels);
+}
+
static void flatten_tree(struct node *tree, struct emitter *emit,
void *etarget, struct data *strbuf,
struct version_info *vi)
@@ -448,6 +510,7 @@ static void flatten_tree(struct node *tree, struct emitter *emit,
emit_symbols_node(tree, emit, etarget, strbuf, vi);
emit_local_fixups_node(tree, emit, etarget, strbuf, vi);
+ emit_fixups_node(tree, emit, etarget, strbuf, vi);
emit->endnode(etarget, tree->labels);
}
--
1.7.12
--
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