xref: /openbmc/u-boot/common/spl/spl_fit.c (revision 679590eb)
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 /**
15  * spl_fit_get_image_node(): By using the matching configuration subnode,
16  * retrieve the name of an image, specified by a property name and an index
17  * into that.
18  * @fit:	Pointer to the FDT blob.
19  * @images:	Offset of the /images subnode.
20  * @type:	Name of the property within the configuration subnode.
21  * @index:	Index into the list of strings in this property.
22  *
23  * Return:	the node offset of the respective image node or a negative
24  * 		error number.
25  */
26 static int spl_fit_get_image_node(const void *fit, int images,
27 				  const char *type, int index)
28 {
29 	const char *name, *str;
30 	int node, conf_node;
31 	int len, i;
32 
33 	conf_node = fit_find_config_node(fit);
34 	if (conf_node < 0) {
35 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
36 		printf("No matching DT out of these options:\n");
37 		for (node = fdt_first_subnode(fit, conf_node);
38 		     node >= 0;
39 		     node = fdt_next_subnode(fit, node)) {
40 			name = fdt_getprop(fit, node, "description", &len);
41 			printf("   %s\n", name);
42 		}
43 #endif
44 		return conf_node;
45 	}
46 
47 	name = fdt_getprop(fit, conf_node, type, &len);
48 	if (!name) {
49 		debug("cannot find property '%s': %d\n", type, len);
50 		return -EINVAL;
51 	}
52 
53 	str = name;
54 	for (i = 0; i < index; i++) {
55 		str = strchr(str, '\0') + 1;
56 		if (!str || (str - name >= len)) {
57 			debug("no string for index %d\n", index);
58 			return -E2BIG;
59 		}
60 	}
61 
62 	debug("%s: '%s'\n", type, str);
63 	node = fdt_subnode_offset(fit, images, str);
64 	if (node < 0) {
65 		debug("cannot find image node '%s': %d\n", str, node);
66 		return -EINVAL;
67 	}
68 
69 	return node;
70 }
71 
72 static int get_aligned_image_offset(struct spl_load_info *info, int offset)
73 {
74 	/*
75 	 * If it is a FS read, get the first address before offset which is
76 	 * aligned to ARCH_DMA_MINALIGN. If it is raw read return the
77 	 * block number to which offset belongs.
78 	 */
79 	if (info->filename)
80 		return offset & ~(ARCH_DMA_MINALIGN - 1);
81 
82 	return offset / info->bl_len;
83 }
84 
85 static int get_aligned_image_overhead(struct spl_load_info *info, int offset)
86 {
87 	/*
88 	 * If it is a FS read, get the difference between the offset and
89 	 * the first address before offset which is aligned to
90 	 * ARCH_DMA_MINALIGN. If it is raw read return the offset within the
91 	 * block.
92 	 */
93 	if (info->filename)
94 		return offset & (ARCH_DMA_MINALIGN - 1);
95 
96 	return offset % info->bl_len;
97 }
98 
99 static int get_aligned_image_size(struct spl_load_info *info, int data_size,
100 				  int offset)
101 {
102 	data_size = data_size + get_aligned_image_overhead(info, offset);
103 
104 	if (info->filename)
105 		return data_size;
106 
107 	return (data_size + info->bl_len - 1) / info->bl_len;
108 }
109 
110 /**
111  * spl_load_fit_image(): load the image described in a certain FIT node
112  * @info:	points to information about the device to load data from
113  * @sector:	the start sector of the FIT image on the device
114  * @fit:	points to the flattened device tree blob describing the FIT
115  * 		image
116  * @base_offset: the beginning of the data area containing the actual
117  *		image data, relative to the beginning of the FIT
118  * @node:	offset of the DT node describing the image to load (relative
119  * 		to @fit)
120  * @image_info:	will be filled with information about the loaded image
121  * 		If the FIT node does not contain a "load" (address) property,
122  * 		the image gets loaded to the address pointed to by the
123  * 		load_addr member in this struct.
124  *
125  * Return:	0 on success or a negative error number.
126  */
127 static int spl_load_fit_image(struct spl_load_info *info, ulong sector,
128 			      void *fit, ulong base_offset, int node,
129 			      struct spl_image_info *image_info)
130 {
131 	ulong offset;
132 	size_t length;
133 	ulong load_addr, load_ptr;
134 	void *src;
135 	ulong overhead;
136 	int nr_sectors;
137 	int align_len = ARCH_DMA_MINALIGN - 1;
138 
139 	offset = fdt_getprop_u32(fit, node, "data-offset");
140 	if (offset == FDT_ERROR)
141 		return -ENOENT;
142 	offset += base_offset;
143 	length = fdt_getprop_u32(fit, node, "data-size");
144 	if (length == FDT_ERROR)
145 		return -ENOENT;
146 	load_addr = fdt_getprop_u32(fit, node, "load");
147 	if (load_addr == FDT_ERROR && image_info)
148 		load_addr = image_info->load_addr;
149 	load_ptr = (load_addr + align_len) & ~align_len;
150 
151 	overhead = get_aligned_image_overhead(info, offset);
152 	nr_sectors = get_aligned_image_size(info, length, offset);
153 
154 	if (info->read(info, sector + get_aligned_image_offset(info, offset),
155 		       nr_sectors, (void*)load_ptr) != nr_sectors)
156 		return -EIO;
157 	debug("image: dst=%lx, offset=%lx, size=%lx\n", load_ptr, offset,
158 	      (unsigned long)length);
159 
160 	src = (void *)load_ptr + overhead;
161 #ifdef CONFIG_SPL_FIT_IMAGE_POST_PROCESS
162 	board_fit_image_post_process(&src, &length);
163 #endif
164 
165 	memcpy((void*)load_addr, src, length);
166 
167 	if (image_info) {
168 		image_info->load_addr = load_addr;
169 		image_info->size = length;
170 		image_info->entry_point = fdt_getprop_u32(fit, node, "entry");
171 	}
172 
173 	return 0;
174 }
175 
176 int spl_load_simple_fit(struct spl_image_info *spl_image,
177 			struct spl_load_info *info, ulong sector, void *fit)
178 {
179 	int sectors;
180 	ulong size;
181 	unsigned long count;
182 	struct spl_image_info image_info;
183 	int node, images, ret;
184 	int base_offset, align_len = ARCH_DMA_MINALIGN - 1;
185 	int index = 0;
186 
187 	/*
188 	 * Figure out where the external images start. This is the base for the
189 	 * data-offset properties in each image.
190 	 */
191 	size = fdt_totalsize(fit);
192 	size = (size + 3) & ~3;
193 	base_offset = (size + 3) & ~3;
194 
195 	/*
196 	 * So far we only have one block of data from the FIT. Read the entire
197 	 * thing, including that first block, placing it so it finishes before
198 	 * where we will load the image.
199 	 *
200 	 * Note that we will load the image such that its first byte will be
201 	 * at the load address. Since that byte may be part-way through a
202 	 * block, we may load the image up to one block before the load
203 	 * address. So take account of that here by subtracting an addition
204 	 * block length from the FIT start position.
205 	 *
206 	 * In fact the FIT has its own load address, but we assume it cannot
207 	 * be before CONFIG_SYS_TEXT_BASE.
208 	 */
209 	fit = (void *)((CONFIG_SYS_TEXT_BASE - size - info->bl_len -
210 			align_len) & ~align_len);
211 	sectors = get_aligned_image_size(info, size, 0);
212 	count = info->read(info, sector, sectors, fit);
213 	debug("fit read sector %lx, sectors=%d, dst=%p, count=%lu\n",
214 	      sector, sectors, fit, count);
215 	if (count == 0)
216 		return -EIO;
217 
218 	/* find the node holding the images information */
219 	images = fdt_path_offset(fit, FIT_IMAGES_PATH);
220 	if (images < 0) {
221 		debug("%s: Cannot find /images node: %d\n", __func__, images);
222 		return -1;
223 	}
224 
225 	/* find the U-Boot image */
226 	node = spl_fit_get_image_node(fit, images, "firmware", 0);
227 	if (node < 0) {
228 		debug("could not find firmware image, trying loadables...\n");
229 		node = spl_fit_get_image_node(fit, images, "loadables", 0);
230 		/*
231 		 * If we pick the U-Boot image from "loadables", start at
232 		 * the second image when later loading additional images.
233 		 */
234 		index = 1;
235 	}
236 	if (node < 0) {
237 		debug("%s: Cannot find u-boot image node: %d\n",
238 		      __func__, node);
239 		return -1;
240 	}
241 
242 	/* Load the image and set up the spl_image structure */
243 	ret = spl_load_fit_image(info, sector, fit, base_offset, node,
244 				 spl_image);
245 	if (ret)
246 		return ret;
247 
248 	spl_image->os = IH_OS_U_BOOT;
249 
250 	/* Figure out which device tree the board wants to use */
251 	node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP, 0);
252 	if (node < 0) {
253 		debug("%s: cannot find FDT node\n", __func__);
254 		return node;
255 	}
256 
257 	/*
258 	 * Read the device tree and place it after the image.
259 	 * Align the destination address to ARCH_DMA_MINALIGN.
260 	 */
261 	image_info.load_addr = spl_image->load_addr + spl_image->size;
262 	ret = spl_load_fit_image(info, sector, fit, base_offset, node,
263 				 &image_info);
264 	if (ret < 0)
265 		return ret;
266 
267 	/* Now check if there are more images for us to load */
268 	for (; ; index++) {
269 		node = spl_fit_get_image_node(fit, images, "loadables", index);
270 		if (node < 0)
271 			break;
272 
273 		ret = spl_load_fit_image(info, sector, fit, base_offset, node,
274 					 &image_info);
275 		if (ret < 0)
276 			continue;
277 
278 		/*
279 		 * If the "firmware" image did not provide an entry point,
280 		 * use the first valid entry point from the loadables.
281 		 */
282 		if (spl_image->entry_point == FDT_ERROR &&
283 		    image_info.entry_point != FDT_ERROR)
284 			spl_image->entry_point = image_info.entry_point;
285 	}
286 
287 	/*
288 	 * If a platform does not provide CONFIG_SYS_UBOOT_START, U-Boot's
289 	 * Makefile will set it to 0 and it will end up as the entry point
290 	 * here. What it actually means is: use the load address.
291 	 */
292 	if (spl_image->entry_point == FDT_ERROR || spl_image->entry_point == 0)
293 		spl_image->entry_point = spl_image->load_addr;
294 
295 	return 0;
296 }
297