common/spl/spl_fit.c

   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
 238         /*
 239          * Figure out where the external images start. This is the base for the
 240          * data-offset properties in each image.
 241          */
 242         size = fdt_totalsize(fit);
 243         size = (size + 3) & ~3;
 244         base_offset = (size + 3) & ~3;
 245
 246         /*
 247          * So far we only have one block of data from the FIT. Read the entire
 248          * thing, including that first block, placing it so it finishes before
 249          * where we will load the image.
 250          *
 251          * Note that we will load the image such that its first byte will be
 252          * at the load address. Since that byte may be part-way through a
 253          * block, we may load the image up to one block before the load
 254          * address. So take account of that here by subtracting an addition
 255          * block length from the FIT start position.
 256          *
 257          * In fact the FIT has its own load address, but we assume it cannot
 258          * be before CONFIG_SYS_TEXT_BASE.
 259          */
 260         fit = (void *)((CONFIG_SYS_TEXT_BASE - size - info->bl_len -
 261                         align_len) & ~align_len);
 262         sectors = get_aligned_image_size(info, size, 0);
 263         count = info->read(info, sector, sectors, fit);
 264         debug("fit read sector %lx, sectors=%d, dst=%p, count=%lu\n",
 265               sector, sectors, fit, count);
 266         if (count == 0)
 267                 return -EIO;
 268
 269         /* find the node holding the images information */
 270         images = fdt_path_offset(fit, FIT_IMAGES_PATH);
 271         if (images < 0) {
 272                 debug("%s: Cannot find /images node: %d\n", __func__, images);
 273                 return -1;
 274         }
 275
 276         /* find the U-Boot image */
 277         node = spl_fit_get_image_node(fit, images, "firmware", 0);
 278         if (node < 0) {
 279                 debug("could not find firmware image, trying loadables...\n");
 280                 node = spl_fit_get_image_node(fit, images, "loadables", 0);
 281         }
 282         if (node < 0) {
 283                 debug("%s: Cannot find u-boot image node: %d\n",
 284                       __func__, node);
 285                 return -1;
 286         }
 287
 288         /* Load the image and set up the spl_image structure */
 289         ret = spl_load_fit_image(info, sector, fit, base_offset, node,
 290                                  spl_image);
 291         if (ret)
 292                 return ret;
 293
 294         spl_image->os = IH_OS_U_BOOT;
 295
 296         /* Figure out which device tree the board wants to use */
 297         node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP, 0);
 298         if (node < 0) {
 299                 debug("%s: cannot find FDT node\n", __func__);
 300                 return node;
 301         }
 302
 303         /*
 304          * Read the device tree and place it after the image.
 305          * Align the destination address to ARCH_DMA_MINALIGN.
 306          */
 307         image_info.load_addr = spl_image->load_addr + spl_image->size;
 308         return spl_load_fit_image(info, sector, fit, base_offset, node,
 309                                   &image_info);
 310 }