xref: /openbmc/u-boot/common/spl/spl_fit.c (revision 7805cdf4)
1 /*
2  * Copyright (C) 2016 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:     GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <errno.h>
10 #include <image.h>
11 #include <libfdt.h>
12 #include <spl.h>
13 
14 #define FDT_ERROR ((ulong)(-1))
15 
16 static ulong fdt_getprop_u32(const void *fdt, int node, const char *prop)
17 {
18 	const u32 *cell;
19 	int len;
20 
21 	cell = fdt_getprop(fdt, node, prop, &len);
22 	if (!cell || len != sizeof(*cell))
23 		return FDT_ERROR;
24 
25 	return fdt32_to_cpu(*cell);
26 }
27 
28 /*
29  * Iterate over all /configurations subnodes and call a platform specific
30  * function to find the matching configuration.
31  * Returns the node offset or a negative error number.
32  */
33 static int spl_fit_find_config_node(const void *fdt)
34 {
35 	const char *name;
36 	int conf, node, len;
37 
38 	conf = fdt_path_offset(fdt, FIT_CONFS_PATH);
39 	if (conf < 0) {
40 		debug("%s: Cannot find /configurations node: %d\n", __func__,
41 		      conf);
42 		return -EINVAL;
43 	}
44 	for (node = fdt_first_subnode(fdt, conf);
45 	     node >= 0;
46 	     node = fdt_next_subnode(fdt, node)) {
47 		name = fdt_getprop(fdt, node, "description", &len);
48 		if (!name) {
49 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
50 			printf("%s: Missing FDT description in DTB\n",
51 			       __func__);
52 #endif
53 			return -EINVAL;
54 		}
55 		if (board_fit_config_name_match(name))
56 			continue;
57 
58 		debug("Selecting config '%s'", name);
59 
60 		return node;
61 	}
62 
63 	return -ENOENT;
64 }
65 
66 /**
67  * spl_fit_get_image_node(): By using the matching configuration subnode,
68  * retrieve the name of an image, specified by a property name and an index
69  * into that.
70  * @fit:	Pointer to the FDT blob.
71  * @images:	Offset of the /images subnode.
72  * @type:	Name of the property within the configuration subnode.
73  * @index:	Index into the list of strings in this property.
74  *
75  * Return:	the node offset of the respective image node or a negative
76  * 		error number.
77  */
78 static int spl_fit_get_image_node(const void *fit, int images,
79 				  const char *type, int index)
80 {
81 	const char *name, *str;
82 	int node, conf_node;
83 	int len, i;
84 
85 	conf_node = spl_fit_find_config_node(fit);
86 	if (conf_node < 0) {
87 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
88 		printf("No matching DT out of these options:\n");
89 		for (node = fdt_first_subnode(fit, conf_node);
90 		     node >= 0;
91 		     node = fdt_next_subnode(fit, node)) {
92 			name = fdt_getprop(fit, node, "description", &len);
93 			printf("   %s\n", name);
94 		}
95 #endif
96 		return conf_node;
97 	}
98 
99 	name = fdt_getprop(fit, conf_node, type, &len);
100 	if (!name) {
101 		debug("cannot find property '%s': %d\n", type, len);
102 		return -EINVAL;
103 	}
104 
105 	str = name;
106 	for (i = 0; i < index; i++) {
107 		str = strchr(str, '\0') + 1;
108 		if (!str || (str - name >= len)) {
109 			debug("no string for index %d\n", index);
110 			return -E2BIG;
111 		}
112 	}
113 
114 	debug("%s: '%s'\n", type, str);
115 	node = fdt_subnode_offset(fit, images, str);
116 	if (node < 0) {
117 		debug("cannot find image node '%s': %d\n", str, node);
118 		return -EINVAL;
119 	}
120 
121 	return node;
122 }
123 
124 static int get_aligned_image_offset(struct spl_load_info *info, int offset)
125 {
126 	/*
127 	 * If it is a FS read, get the first address before offset which is
128 	 * aligned to ARCH_DMA_MINALIGN. If it is raw read return the
129 	 * block number to which offset belongs.
130 	 */
131 	if (info->filename)
132 		return offset & ~(ARCH_DMA_MINALIGN - 1);
133 
134 	return offset / info->bl_len;
135 }
136 
137 static int get_aligned_image_overhead(struct spl_load_info *info, int offset)
138 {
139 	/*
140 	 * If it is a FS read, get the difference between the offset and
141 	 * the first address before offset which is aligned to
142 	 * ARCH_DMA_MINALIGN. If it is raw read return the offset within the
143 	 * block.
144 	 */
145 	if (info->filename)
146 		return offset & (ARCH_DMA_MINALIGN - 1);
147 
148 	return offset % info->bl_len;
149 }
150 
151 static int get_aligned_image_size(struct spl_load_info *info, int data_size,
152 				  int offset)
153 {
154 	data_size = data_size + get_aligned_image_overhead(info, offset);
155 
156 	if (info->filename)
157 		return data_size;
158 
159 	return (data_size + info->bl_len - 1) / info->bl_len;
160 }
161 
162 /**
163  * spl_load_fit_image(): load the image described in a certain FIT node
164  * @info:	points to information about the device to load data from
165  * @sector:	the start sector of the FIT image on the device
166  * @fit:	points to the flattened device tree blob describing the FIT
167  * 		image
168  * @base_offset: the beginning of the data area containing the actual
169  *		image data, relative to the beginning of the FIT
170  * @node:	offset of the DT node describing the image to load (relative
171  * 		to @fit)
172  * @image_info:	will be filled with information about the loaded image
173  * 		If the FIT node does not contain a "load" (address) property,
174  * 		the image gets loaded to the address pointed to by the
175  * 		load_addr member in this struct.
176  *
177  * Return:	0 on success or a negative error number.
178  */
179 static int spl_load_fit_image(struct spl_load_info *info, ulong sector,
180 			      void *fit, ulong base_offset, int node,
181 			      struct spl_image_info *image_info)
182 {
183 	ulong offset;
184 	size_t length;
185 	ulong load_addr, load_ptr;
186 	void *src;
187 	ulong overhead;
188 	int nr_sectors;
189 	int align_len = ARCH_DMA_MINALIGN - 1;
190 
191 	offset = fdt_getprop_u32(fit, node, "data-offset");
192 	if (offset == FDT_ERROR)
193 		return -ENOENT;
194 	offset += base_offset;
195 	length = fdt_getprop_u32(fit, node, "data-size");
196 	if (length == FDT_ERROR)
197 		return -ENOENT;
198 	load_addr = fdt_getprop_u32(fit, node, "load");
199 	if (load_addr == FDT_ERROR && image_info)
200 		load_addr = image_info->load_addr;
201 	load_ptr = (load_addr + align_len) & ~align_len;
202 
203 	overhead = get_aligned_image_overhead(info, offset);
204 	nr_sectors = get_aligned_image_size(info, length, offset);
205 
206 	if (info->read(info, sector + get_aligned_image_offset(info, offset),
207 		       nr_sectors, (void*)load_ptr) != nr_sectors)
208 		return -EIO;
209 	debug("image: dst=%lx, offset=%lx, size=%lx\n", load_ptr, offset,
210 	      (unsigned long)length);
211 
212 	src = (void *)load_ptr + overhead;
213 #ifdef CONFIG_SPL_FIT_IMAGE_POST_PROCESS
214 	board_fit_image_post_process(&src, &length);
215 #endif
216 
217 	memcpy((void*)load_addr, src, length);
218 
219 	if (image_info) {
220 		image_info->load_addr = load_addr;
221 		image_info->size = length;
222 		image_info->entry_point = fdt_getprop_u32(fit, node, "entry");
223 	}
224 
225 	return 0;
226 }
227 
228 int spl_load_simple_fit(struct spl_image_info *spl_image,
229 			struct spl_load_info *info, ulong sector, void *fit)
230 {
231 	int sectors;
232 	ulong size;
233 	unsigned long count;
234 	struct spl_image_info image_info;
235 	int node, images, ret;
236 	int base_offset, align_len = ARCH_DMA_MINALIGN - 1;
237 	int index = 0;
238 
239 	/*
240 	 * Figure out where the external images start. This is the base for the
241 	 * data-offset properties in each image.
242 	 */
243 	size = fdt_totalsize(fit);
244 	size = (size + 3) & ~3;
245 	base_offset = (size + 3) & ~3;
246 
247 	/*
248 	 * So far we only have one block of data from the FIT. Read the entire
249 	 * thing, including that first block, placing it so it finishes before
250 	 * where we will load the image.
251 	 *
252 	 * Note that we will load the image such that its first byte will be
253 	 * at the load address. Since that byte may be part-way through a
254 	 * block, we may load the image up to one block before the load
255 	 * address. So take account of that here by subtracting an addition
256 	 * block length from the FIT start position.
257 	 *
258 	 * In fact the FIT has its own load address, but we assume it cannot
259 	 * be before CONFIG_SYS_TEXT_BASE.
260 	 */
261 	fit = (void *)((CONFIG_SYS_TEXT_BASE - size - info->bl_len -
262 			align_len) & ~align_len);
263 	sectors = get_aligned_image_size(info, size, 0);
264 	count = info->read(info, sector, sectors, fit);
265 	debug("fit read sector %lx, sectors=%d, dst=%p, count=%lu\n",
266 	      sector, sectors, fit, count);
267 	if (count == 0)
268 		return -EIO;
269 
270 	/* find the node holding the images information */
271 	images = fdt_path_offset(fit, FIT_IMAGES_PATH);
272 	if (images < 0) {
273 		debug("%s: Cannot find /images node: %d\n", __func__, images);
274 		return -1;
275 	}
276 
277 	/* find the U-Boot image */
278 	node = spl_fit_get_image_node(fit, images, "firmware", 0);
279 	if (node < 0) {
280 		debug("could not find firmware image, trying loadables...\n");
281 		node = spl_fit_get_image_node(fit, images, "loadables", 0);
282 		/*
283 		 * If we pick the U-Boot image from "loadables", start at
284 		 * the second image when later loading additional images.
285 		 */
286 		index = 1;
287 	}
288 	if (node < 0) {
289 		debug("%s: Cannot find u-boot image node: %d\n",
290 		      __func__, node);
291 		return -1;
292 	}
293 
294 	/* Load the image and set up the spl_image structure */
295 	ret = spl_load_fit_image(info, sector, fit, base_offset, node,
296 				 spl_image);
297 	if (ret)
298 		return ret;
299 
300 	spl_image->os = IH_OS_U_BOOT;
301 
302 	/* Figure out which device tree the board wants to use */
303 	node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP, 0);
304 	if (node < 0) {
305 		debug("%s: cannot find FDT node\n", __func__);
306 		return node;
307 	}
308 
309 	/*
310 	 * Read the device tree and place it after the image.
311 	 * Align the destination address to ARCH_DMA_MINALIGN.
312 	 */
313 	image_info.load_addr = spl_image->load_addr + spl_image->size;
314 	ret = spl_load_fit_image(info, sector, fit, base_offset, node,
315 				 &image_info);
316 	if (ret < 0)
317 		return ret;
318 
319 	/* Now check if there are more images for us to load */
320 	for (; ; index++) {
321 		node = spl_fit_get_image_node(fit, images, "loadables", index);
322 		if (node < 0)
323 			break;
324 
325 		ret = spl_load_fit_image(info, sector, fit, base_offset, node,
326 					 &image_info);
327 		if (ret < 0)
328 			continue;
329 
330 		/*
331 		 * If the "firmware" image did not provide an entry point,
332 		 * use the first valid entry point from the loadables.
333 		 */
334 		if (spl_image->entry_point == FDT_ERROR &&
335 		    image_info.entry_point != FDT_ERROR)
336 			spl_image->entry_point = image_info.entry_point;
337 	}
338 
339 	/*
340 	 * If a platform does not provide CONFIG_SYS_UBOOT_START, U-Boot's
341 	 * Makefile will set it to 0 and it will end up as the entry point
342 	 * here. What it actually means is: use the load address.
343 	 */
344 	if (spl_image->entry_point == FDT_ERROR || spl_image->entry_point == 0)
345 		spl_image->entry_point = spl_image->load_addr;
346 
347 	return 0;
348 }
349