of/flattree: Merge unflatten_dt_node

Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>

1 files changed, 200 insertions, 0 deletions

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 5cdd958db9af..6852ecf6d1e1 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -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;
+}