of/flattree: Merge unflatten_dt_node
[firefly-linux-kernel-4.4.55.git] / drivers / of / fdt.c
index 5cdd958db9af6210d40dd9bce06e56b326c17d49..6852ecf6d1e1062c87f54fa5306714e1ac346cb1 100644 (file)
@@ -166,3 +166,203 @@ int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
        return 0;
 }
 
+static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
+                                      unsigned long align)
+{
+       void *res;
+
+       *mem = _ALIGN(*mem, align);
+       res = (void *)*mem;
+       *mem += size;
+
+       return res;
+}
+
+/**
+ * unflatten_dt_node - Alloc and populate a device_node from the flat tree
+ * @p: pointer to node in flat tree
+ * @dad: Parent struct device_node
+ * @allnextpp: pointer to ->allnext from last allocated device_node
+ * @fpsize: Size of the node path up at the current depth.
+ */
+unsigned long __init unflatten_dt_node(unsigned long mem,
+                                       unsigned long *p,
+                                       struct device_node *dad,
+                                       struct device_node ***allnextpp,
+                                       unsigned long fpsize)
+{
+       struct device_node *np;
+       struct property *pp, **prev_pp = NULL;
+       char *pathp;
+       u32 tag;
+       unsigned int l, allocl;
+       int has_name = 0;
+       int new_format = 0;
+
+       tag = *((u32 *)(*p));
+       if (tag != OF_DT_BEGIN_NODE) {
+               pr_err("Weird tag at start of node: %x\n", tag);
+               return mem;
+       }
+       *p += 4;
+       pathp = (char *)*p;
+       l = allocl = strlen(pathp) + 1;
+       *p = _ALIGN(*p + l, 4);
+
+       /* version 0x10 has a more compact unit name here instead of the full
+        * path. we accumulate the full path size using "fpsize", we'll rebuild
+        * it later. We detect this because the first character of the name is
+        * not '/'.
+        */
+       if ((*pathp) != '/') {
+               new_format = 1;
+               if (fpsize == 0) {
+                       /* root node: special case. fpsize accounts for path
+                        * plus terminating zero. root node only has '/', so
+                        * fpsize should be 2, but we want to avoid the first
+                        * level nodes to have two '/' so we use fpsize 1 here
+                        */
+                       fpsize = 1;
+                       allocl = 2;
+               } else {
+                       /* account for '/' and path size minus terminal 0
+                        * already in 'l'
+                        */
+                       fpsize += l;
+                       allocl = fpsize;
+               }
+       }
+
+       np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
+                               __alignof__(struct device_node));
+       if (allnextpp) {
+               memset(np, 0, sizeof(*np));
+               np->full_name = ((char *)np) + sizeof(struct device_node);
+               if (new_format) {
+                       char *fn = np->full_name;
+                       /* rebuild full path for new format */
+                       if (dad && dad->parent) {
+                               strcpy(fn, dad->full_name);
+#ifdef DEBUG
+                               if ((strlen(fn) + l + 1) != allocl) {
+                                       pr_debug("%s: p: %d, l: %d, a: %d\n",
+                                               pathp, (int)strlen(fn),
+                                               l, allocl);
+                               }
+#endif
+                               fn += strlen(fn);
+                       }
+                       *(fn++) = '/';
+                       memcpy(fn, pathp, l);
+               } else
+                       memcpy(np->full_name, pathp, l);
+               prev_pp = &np->properties;
+               **allnextpp = np;
+               *allnextpp = &np->allnext;
+               if (dad != NULL) {
+                       np->parent = dad;
+                       /* we temporarily use the next field as `last_child'*/
+                       if (dad->next == NULL)
+                               dad->child = np;
+                       else
+                               dad->next->sibling = np;
+                       dad->next = np;
+               }
+               kref_init(&np->kref);
+       }
+       while (1) {
+               u32 sz, noff;
+               char *pname;
+
+               tag = *((u32 *)(*p));
+               if (tag == OF_DT_NOP) {
+                       *p += 4;
+                       continue;
+               }
+               if (tag != OF_DT_PROP)
+                       break;
+               *p += 4;
+               sz = *((u32 *)(*p));
+               noff = *((u32 *)((*p) + 4));
+               *p += 8;
+               if (initial_boot_params->version < 0x10)
+                       *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
+
+               pname = find_flat_dt_string(noff);
+               if (pname == NULL) {
+                       pr_info("Can't find property name in list !\n");
+                       break;
+               }
+               if (strcmp(pname, "name") == 0)
+                       has_name = 1;
+               l = strlen(pname) + 1;
+               pp = unflatten_dt_alloc(&mem, sizeof(struct property),
+                                       __alignof__(struct property));
+               if (allnextpp) {
+                       if (strcmp(pname, "linux,phandle") == 0) {
+                               np->node = *((u32 *)*p);
+                               if (np->linux_phandle == 0)
+                                       np->linux_phandle = np->node;
+                       }
+                       if (strcmp(pname, "ibm,phandle") == 0)
+                               np->linux_phandle = *((u32 *)*p);
+                       pp->name = pname;
+                       pp->length = sz;
+                       pp->value = (void *)*p;
+                       *prev_pp = pp;
+                       prev_pp = &pp->next;
+               }
+               *p = _ALIGN((*p) + sz, 4);
+       }
+       /* with version 0x10 we may not have the name property, recreate
+        * it here from the unit name if absent
+        */
+       if (!has_name) {
+               char *p1 = pathp, *ps = pathp, *pa = NULL;
+               int sz;
+
+               while (*p1) {
+                       if ((*p1) == '@')
+                               pa = p1;
+                       if ((*p1) == '/')
+                               ps = p1 + 1;
+                       p1++;
+               }
+               if (pa < ps)
+                       pa = p1;
+               sz = (pa - ps) + 1;
+               pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
+                                       __alignof__(struct property));
+               if (allnextpp) {
+                       pp->name = "name";
+                       pp->length = sz;
+                       pp->value = pp + 1;
+                       *prev_pp = pp;
+                       prev_pp = &pp->next;
+                       memcpy(pp->value, ps, sz - 1);
+                       ((char *)pp->value)[sz - 1] = 0;
+                       pr_debug("fixed up name for %s -> %s\n", pathp,
+                               (char *)pp->value);
+               }
+       }
+       if (allnextpp) {
+               *prev_pp = NULL;
+               np->name = of_get_property(np, "name", NULL);
+               np->type = of_get_property(np, "device_type", NULL);
+
+               if (!np->name)
+                       np->name = "<NULL>";
+               if (!np->type)
+                       np->type = "<NULL>";
+       }
+       while (tag == OF_DT_BEGIN_NODE) {
+               mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
+               tag = *((u32 *)(*p));
+       }
+       if (tag != OF_DT_END_NODE) {
+               pr_err("Weird tag at end of node: %x\n", tag);
+               return mem;
+       }
+       *p += 4;
+       return mem;
+}