xref: /openbmc/u-boot/lib/of_live.c (revision 83d290c56fab2d38cd1ab4c4cc7099559c1d5046)
1*83d290c5STom Rini // SPDX-License-Identifier: GPL-2.0+
28b50d526SSimon Glass /*
38b50d526SSimon Glass  * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
48b50d526SSimon Glass  * benh@kernel.crashing.org
58b50d526SSimon Glass  *
68b50d526SSimon Glass  * Based on parts of drivers/of/fdt.c from Linux v4.9
78b50d526SSimon Glass  * Modifications for U-Boot
88b50d526SSimon Glass  * Copyright (c) 2017 Google, Inc
98b50d526SSimon Glass  */
108b50d526SSimon Glass 
118b50d526SSimon Glass #include <common.h>
12b08c8c48SMasahiro Yamada #include <linux/libfdt.h>
138b50d526SSimon Glass #include <of_live.h>
148b50d526SSimon Glass #include <malloc.h>
158b50d526SSimon Glass #include <dm/of_access.h>
168b50d526SSimon Glass #include <linux/err.h>
178b50d526SSimon Glass 
unflatten_dt_alloc(void ** mem,unsigned long size,unsigned long align)188b50d526SSimon Glass static void *unflatten_dt_alloc(void **mem, unsigned long size,
198b50d526SSimon Glass 				unsigned long align)
208b50d526SSimon Glass {
218b50d526SSimon Glass 	void *res;
228b50d526SSimon Glass 
238b50d526SSimon Glass 	*mem = PTR_ALIGN(*mem, align);
248b50d526SSimon Glass 	res = *mem;
258b50d526SSimon Glass 	*mem += size;
268b50d526SSimon Glass 
278b50d526SSimon Glass 	return res;
288b50d526SSimon Glass }
298b50d526SSimon Glass 
308b50d526SSimon Glass /**
318b50d526SSimon Glass  * unflatten_dt_node() - Alloc and populate a device_node from the flat tree
328b50d526SSimon Glass  * @blob: The parent device tree blob
338b50d526SSimon Glass  * @mem: Memory chunk to use for allocating device nodes and properties
348b50d526SSimon Glass  * @poffset: pointer to node in flat tree
358b50d526SSimon Glass  * @dad: Parent struct device_node
368b50d526SSimon Glass  * @nodepp: The device_node tree created by the call
378b50d526SSimon Glass  * @fpsize: Size of the node path up at t05he current depth.
388b50d526SSimon Glass  * @dryrun: If true, do not allocate device nodes but still calculate needed
398b50d526SSimon Glass  * memory size
408b50d526SSimon Glass  */
unflatten_dt_node(const void * blob,void * mem,int * poffset,struct device_node * dad,struct device_node ** nodepp,unsigned long fpsize,bool dryrun)418b50d526SSimon Glass static void *unflatten_dt_node(const void *blob, void *mem, int *poffset,
428b50d526SSimon Glass 			       struct device_node *dad,
438b50d526SSimon Glass 			       struct device_node **nodepp,
448b50d526SSimon Glass 			       unsigned long fpsize, bool dryrun)
458b50d526SSimon Glass {
468b50d526SSimon Glass 	const __be32 *p;
478b50d526SSimon Glass 	struct device_node *np;
488b50d526SSimon Glass 	struct property *pp, **prev_pp = NULL;
498b50d526SSimon Glass 	const char *pathp;
508b50d526SSimon Glass 	int l;
518b50d526SSimon Glass 	unsigned int allocl;
528b50d526SSimon Glass 	static int depth;
538b50d526SSimon Glass 	int old_depth;
548b50d526SSimon Glass 	int offset;
558b50d526SSimon Glass 	int has_name = 0;
568b50d526SSimon Glass 	int new_format = 0;
578b50d526SSimon Glass 
588b50d526SSimon Glass 	pathp = fdt_get_name(blob, *poffset, &l);
598b50d526SSimon Glass 	if (!pathp)
608b50d526SSimon Glass 		return mem;
618b50d526SSimon Glass 
628b50d526SSimon Glass 	allocl = ++l;
638b50d526SSimon Glass 
648b50d526SSimon Glass 	/*
658b50d526SSimon Glass 	 * version 0x10 has a more compact unit name here instead of the full
668b50d526SSimon Glass 	 * path. we accumulate the full path size using "fpsize", we'll rebuild
678b50d526SSimon Glass 	 * it later. We detect this because the first character of the name is
688b50d526SSimon Glass 	 * not '/'.
698b50d526SSimon Glass 	 */
708b50d526SSimon Glass 	if ((*pathp) != '/') {
718b50d526SSimon Glass 		new_format = 1;
728b50d526SSimon Glass 		if (fpsize == 0) {
738b50d526SSimon Glass 			/*
748b50d526SSimon Glass 			 * root node: special case. fpsize accounts for path
758b50d526SSimon Glass 			 * plus terminating zero. root node only has '/', so
768b50d526SSimon Glass 			 * fpsize should be 2, but we want to avoid the first
778b50d526SSimon Glass 			 * level nodes to have two '/' so we use fpsize 1 here
788b50d526SSimon Glass 			 */
798b50d526SSimon Glass 			fpsize = 1;
808b50d526SSimon Glass 			allocl = 2;
818b50d526SSimon Glass 			l = 1;
828b50d526SSimon Glass 			pathp = "";
838b50d526SSimon Glass 		} else {
848b50d526SSimon Glass 			/*
858b50d526SSimon Glass 			 * account for '/' and path size minus terminal 0
868b50d526SSimon Glass 			 * already in 'l'
878b50d526SSimon Glass 			 */
888b50d526SSimon Glass 			fpsize += l;
898b50d526SSimon Glass 			allocl = fpsize;
908b50d526SSimon Glass 		}
918b50d526SSimon Glass 	}
928b50d526SSimon Glass 
938b50d526SSimon Glass 	np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
948b50d526SSimon Glass 				__alignof__(struct device_node));
958b50d526SSimon Glass 	if (!dryrun) {
968b50d526SSimon Glass 		char *fn;
978b50d526SSimon Glass 
988b50d526SSimon Glass 		fn = (char *)np + sizeof(*np);
998b50d526SSimon Glass 		np->full_name = fn;
1008b50d526SSimon Glass 		if (new_format) {
1018b50d526SSimon Glass 			/* rebuild full path for new format */
1028b50d526SSimon Glass 			if (dad && dad->parent) {
1038b50d526SSimon Glass 				strcpy(fn, dad->full_name);
1048b50d526SSimon Glass #ifdef DEBUG
1058b50d526SSimon Glass 				if ((strlen(fn) + l + 1) != allocl) {
1068b50d526SSimon Glass 					debug("%s: p: %d, l: %d, a: %d\n",
1078b50d526SSimon Glass 					      pathp, (int)strlen(fn), l,
1088b50d526SSimon Glass 					      allocl);
1098b50d526SSimon Glass 				}
1108b50d526SSimon Glass #endif
1118b50d526SSimon Glass 				fn += strlen(fn);
1128b50d526SSimon Glass 			}
1138b50d526SSimon Glass 			*(fn++) = '/';
1148b50d526SSimon Glass 		}
1158b50d526SSimon Glass 		memcpy(fn, pathp, l);
1168b50d526SSimon Glass 
1178b50d526SSimon Glass 		prev_pp = &np->properties;
1188b50d526SSimon Glass 		if (dad != NULL) {
1198b50d526SSimon Glass 			np->parent = dad;
1208b50d526SSimon Glass 			np->sibling = dad->child;
1218b50d526SSimon Glass 			dad->child = np;
1228b50d526SSimon Glass 		}
1238b50d526SSimon Glass 	}
1248b50d526SSimon Glass 	/* process properties */
1258b50d526SSimon Glass 	for (offset = fdt_first_property_offset(blob, *poffset);
1268b50d526SSimon Glass 	     (offset >= 0);
1278b50d526SSimon Glass 	     (offset = fdt_next_property_offset(blob, offset))) {
1288b50d526SSimon Glass 		const char *pname;
1298b50d526SSimon Glass 		int sz;
1308b50d526SSimon Glass 
1318b50d526SSimon Glass 		p = fdt_getprop_by_offset(blob, offset, &pname, &sz);
1328b50d526SSimon Glass 		if (!p) {
1338b50d526SSimon Glass 			offset = -FDT_ERR_INTERNAL;
1348b50d526SSimon Glass 			break;
1358b50d526SSimon Glass 		}
1368b50d526SSimon Glass 
1378b50d526SSimon Glass 		if (pname == NULL) {
1388b50d526SSimon Glass 			debug("Can't find property name in list !\n");
1398b50d526SSimon Glass 			break;
1408b50d526SSimon Glass 		}
1418b50d526SSimon Glass 		if (strcmp(pname, "name") == 0)
1428b50d526SSimon Glass 			has_name = 1;
1438b50d526SSimon Glass 		pp = unflatten_dt_alloc(&mem, sizeof(struct property),
1448b50d526SSimon Glass 					__alignof__(struct property));
1458b50d526SSimon Glass 		if (!dryrun) {
1468b50d526SSimon Glass 			/*
1478b50d526SSimon Glass 			 * We accept flattened tree phandles either in
1488b50d526SSimon Glass 			 * ePAPR-style "phandle" properties, or the
1498b50d526SSimon Glass 			 * legacy "linux,phandle" properties.  If both
1508b50d526SSimon Glass 			 * appear and have different values, things
1518b50d526SSimon Glass 			 * will get weird.  Don't do that. */
1528b50d526SSimon Glass 			if ((strcmp(pname, "phandle") == 0) ||
1538b50d526SSimon Glass 			    (strcmp(pname, "linux,phandle") == 0)) {
1548b50d526SSimon Glass 				if (np->phandle == 0)
1558b50d526SSimon Glass 					np->phandle = be32_to_cpup(p);
1568b50d526SSimon Glass 			}
1578b50d526SSimon Glass 			/*
1588b50d526SSimon Glass 			 * And we process the "ibm,phandle" property
1598b50d526SSimon Glass 			 * used in pSeries dynamic device tree
1608b50d526SSimon Glass 			 * stuff */
1618b50d526SSimon Glass 			if (strcmp(pname, "ibm,phandle") == 0)
1628b50d526SSimon Glass 				np->phandle = be32_to_cpup(p);
1638b50d526SSimon Glass 			pp->name = (char *)pname;
1648b50d526SSimon Glass 			pp->length = sz;
1658b50d526SSimon Glass 			pp->value = (__be32 *)p;
1668b50d526SSimon Glass 			*prev_pp = pp;
1678b50d526SSimon Glass 			prev_pp = &pp->next;
1688b50d526SSimon Glass 		}
1698b50d526SSimon Glass 	}
1708b50d526SSimon Glass 	/*
1718b50d526SSimon Glass 	 * with version 0x10 we may not have the name property, recreate
1728b50d526SSimon Glass 	 * it here from the unit name if absent
1738b50d526SSimon Glass 	 */
1748b50d526SSimon Glass 	if (!has_name) {
1758b50d526SSimon Glass 		const char *p1 = pathp, *ps = pathp, *pa = NULL;
1768b50d526SSimon Glass 		int sz;
1778b50d526SSimon Glass 
1788b50d526SSimon Glass 		while (*p1) {
1798b50d526SSimon Glass 			if ((*p1) == '@')
1808b50d526SSimon Glass 				pa = p1;
1818b50d526SSimon Glass 			if ((*p1) == '/')
1828b50d526SSimon Glass 				ps = p1 + 1;
1838b50d526SSimon Glass 			p1++;
1848b50d526SSimon Glass 		}
1858b50d526SSimon Glass 		if (pa < ps)
1868b50d526SSimon Glass 			pa = p1;
1878b50d526SSimon Glass 		sz = (pa - ps) + 1;
1888b50d526SSimon Glass 		pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
1898b50d526SSimon Glass 					__alignof__(struct property));
1908b50d526SSimon Glass 		if (!dryrun) {
1918b50d526SSimon Glass 			pp->name = "name";
1928b50d526SSimon Glass 			pp->length = sz;
1938b50d526SSimon Glass 			pp->value = pp + 1;
1948b50d526SSimon Glass 			*prev_pp = pp;
1958b50d526SSimon Glass 			prev_pp = &pp->next;
1968b50d526SSimon Glass 			memcpy(pp->value, ps, sz - 1);
1978b50d526SSimon Glass 			((char *)pp->value)[sz - 1] = 0;
1988b50d526SSimon Glass 			debug("fixed up name for %s -> %s\n", pathp,
1998b50d526SSimon Glass 			      (char *)pp->value);
2008b50d526SSimon Glass 		}
2018b50d526SSimon Glass 	}
2028b50d526SSimon Glass 	if (!dryrun) {
2038b50d526SSimon Glass 		*prev_pp = NULL;
2048b50d526SSimon Glass 		np->name = of_get_property(np, "name", NULL);
2058b50d526SSimon Glass 		np->type = of_get_property(np, "device_type", NULL);
2068b50d526SSimon Glass 
2078b50d526SSimon Glass 		if (!np->name)
2088b50d526SSimon Glass 			np->name = "<NULL>";
2098b50d526SSimon Glass 		if (!np->type)
2108b50d526SSimon Glass 			np->type = "<NULL>";	}
2118b50d526SSimon Glass 
2128b50d526SSimon Glass 	old_depth = depth;
2138b50d526SSimon Glass 	*poffset = fdt_next_node(blob, *poffset, &depth);
2148b50d526SSimon Glass 	if (depth < 0)
2158b50d526SSimon Glass 		depth = 0;
216c1eb3d59SSimon Glass 	while (*poffset > 0 && depth > old_depth) {
2178b50d526SSimon Glass 		mem = unflatten_dt_node(blob, mem, poffset, np, NULL,
2188b50d526SSimon Glass 					fpsize, dryrun);
219c1eb3d59SSimon Glass 		if (!mem)
220c1eb3d59SSimon Glass 			return NULL;
221c1eb3d59SSimon Glass 	}
2228b50d526SSimon Glass 
2238b50d526SSimon Glass 	if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND) {
2248b50d526SSimon Glass 		debug("unflatten: error %d processing FDT\n", *poffset);
2258b50d526SSimon Glass 		return NULL;
2268b50d526SSimon Glass 	}
2278b50d526SSimon Glass 
2288b50d526SSimon Glass 	/*
2298b50d526SSimon Glass 	 * Reverse the child list. Some drivers assumes node order matches .dts
2308b50d526SSimon Glass 	 * node order
2318b50d526SSimon Glass 	 */
2328b50d526SSimon Glass 	if (!dryrun && np->child) {
2338b50d526SSimon Glass 		struct device_node *child = np->child;
2348b50d526SSimon Glass 		np->child = NULL;
2358b50d526SSimon Glass 		while (child) {
2368b50d526SSimon Glass 			struct device_node *next = child->sibling;
2378b50d526SSimon Glass 
2388b50d526SSimon Glass 			child->sibling = np->child;
2398b50d526SSimon Glass 			np->child = child;
2408b50d526SSimon Glass 			child = next;
2418b50d526SSimon Glass 		}
2428b50d526SSimon Glass 	}
2438b50d526SSimon Glass 
2448b50d526SSimon Glass 	if (nodepp)
2458b50d526SSimon Glass 		*nodepp = np;
2468b50d526SSimon Glass 
2478b50d526SSimon Glass 	return mem;
2488b50d526SSimon Glass }
2498b50d526SSimon Glass 
2508b50d526SSimon Glass /**
2518b50d526SSimon Glass  * unflatten_device_tree() - create tree of device_nodes from flat blob
2528b50d526SSimon Glass  *
2538b50d526SSimon Glass  * unflattens a device-tree, creating the
2548b50d526SSimon Glass  * tree of struct device_node. It also fills the "name" and "type"
2558b50d526SSimon Glass  * pointers of the nodes so the normal device-tree walking functions
2568b50d526SSimon Glass  * can be used.
2578b50d526SSimon Glass  * @blob: The blob to expand
2588b50d526SSimon Glass  * @mynodes: The device_node tree created by the call
2598b50d526SSimon Glass  * @return 0 if OK, -ve on error
2608b50d526SSimon Glass  */
unflatten_device_tree(const void * blob,struct device_node ** mynodes)2618b50d526SSimon Glass static int unflatten_device_tree(const void *blob,
2628b50d526SSimon Glass 				 struct device_node **mynodes)
2638b50d526SSimon Glass {
2648b50d526SSimon Glass 	unsigned long size;
2658b50d526SSimon Glass 	int start;
2668b50d526SSimon Glass 	void *mem;
2678b50d526SSimon Glass 
2688b50d526SSimon Glass 	debug(" -> unflatten_device_tree()\n");
2698b50d526SSimon Glass 
2708b50d526SSimon Glass 	if (!blob) {
2718b50d526SSimon Glass 		debug("No device tree pointer\n");
2728b50d526SSimon Glass 		return -EINVAL;
2738b50d526SSimon Glass 	}
2748b50d526SSimon Glass 
2758b50d526SSimon Glass 	debug("Unflattening device tree:\n");
2768b50d526SSimon Glass 	debug("magic: %08x\n", fdt_magic(blob));
2778b50d526SSimon Glass 	debug("size: %08x\n", fdt_totalsize(blob));
2788b50d526SSimon Glass 	debug("version: %08x\n", fdt_version(blob));
2798b50d526SSimon Glass 
2808b50d526SSimon Glass 	if (fdt_check_header(blob)) {
2818b50d526SSimon Glass 		debug("Invalid device tree blob header\n");
2828b50d526SSimon Glass 		return -EINVAL;
2838b50d526SSimon Glass 	}
2848b50d526SSimon Glass 
2858b50d526SSimon Glass 	/* First pass, scan for size */
2868b50d526SSimon Glass 	start = 0;
2878b50d526SSimon Glass 	size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL,
2888b50d526SSimon Glass 						0, true);
289c1eb3d59SSimon Glass 	if (!size)
290c1eb3d59SSimon Glass 		return -EFAULT;
2918b50d526SSimon Glass 	size = ALIGN(size, 4);
2928b50d526SSimon Glass 
2938b50d526SSimon Glass 	debug("  size is %lx, allocating...\n", size);
2948b50d526SSimon Glass 
2958b50d526SSimon Glass 	/* Allocate memory for the expanded device tree */
2968b50d526SSimon Glass 	mem = malloc(size + 4);
2978b50d526SSimon Glass 	memset(mem, '\0', size);
2988b50d526SSimon Glass 
2998b50d526SSimon Glass 	*(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
3008b50d526SSimon Glass 
3018b50d526SSimon Glass 	debug("  unflattening %p...\n", mem);
3028b50d526SSimon Glass 
3038b50d526SSimon Glass 	/* Second pass, do actual unflattening */
3048b50d526SSimon Glass 	start = 0;
3058b50d526SSimon Glass 	unflatten_dt_node(blob, mem, &start, NULL, mynodes, 0, false);
3068b50d526SSimon Glass 	if (be32_to_cpup(mem + size) != 0xdeadbeef) {
3078b50d526SSimon Glass 		debug("End of tree marker overwritten: %08x\n",
3088b50d526SSimon Glass 		      be32_to_cpup(mem + size));
3098b50d526SSimon Glass 		return -ENOSPC;
3108b50d526SSimon Glass 	}
3118b50d526SSimon Glass 
3128b50d526SSimon Glass 	debug(" <- unflatten_device_tree()\n");
3138b50d526SSimon Glass 
3148b50d526SSimon Glass 	return 0;
3158b50d526SSimon Glass }
3168b50d526SSimon Glass 
of_live_build(const void * fdt_blob,struct device_node ** rootp)3178b50d526SSimon Glass int of_live_build(const void *fdt_blob, struct device_node **rootp)
3188b50d526SSimon Glass {
3198b50d526SSimon Glass 	int ret;
3208b50d526SSimon Glass 
3218b50d526SSimon Glass 	debug("%s: start\n", __func__);
3228b50d526SSimon Glass 	ret = unflatten_device_tree(fdt_blob, rootp);
3238b50d526SSimon Glass 	if (ret) {
3248b50d526SSimon Glass 		debug("Failed to create live tree: err=%d\n", ret);
3258b50d526SSimon Glass 		return ret;
3268b50d526SSimon Glass 	}
3278b50d526SSimon Glass 	ret = of_alias_scan();
3288b50d526SSimon Glass 	if (ret) {
3298b50d526SSimon Glass 		debug("Failed to scan live tree aliases: err=%d\n", ret);
3308b50d526SSimon Glass 		return ret;
3318b50d526SSimon Glass 	}
3328b50d526SSimon Glass 	debug("%s: stop\n", __func__);
3338b50d526SSimon Glass 
3348b50d526SSimon Glass 	return ret;
3358b50d526SSimon Glass }
336