boot/common_fit.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Google, Inc
   4  * Written by Simon Glass <sjg@chromium.org>
   5  */
   6
   7 #include <common.h>
   8 #include <errno.h>
   9 #include <image.h>
  10 #include <log.h>
  11 #include <linux/libfdt.h>
  12
  13 ulong fdt_getprop_u32(const void *fdt, int node, const char *prop)
  14 {
  15         const u32 *cell;
  16         int len;
  17
  18         cell = fdt_getprop(fdt, node, prop, &len);
  19         if (!cell || len != sizeof(*cell))
  20                 return FDT_ERROR;
  21
  22         return fdt32_to_cpu(*cell);
  23 }
  24
  25 __weak int board_fit_config_name_match(const char *name)
  26 {
  27         return -EINVAL;
  28 }
  29
  30 /*
  31  * Iterate over all /configurations subnodes and call a platform specific
  32  * function to find the matching configuration.
  33  * Returns the node offset or a negative error number.
  34  */
  35 int fit_find_config_node(const void *fdt)
  36 {
  37         const char *name;
  38         int conf, node, len;
  39         const char *dflt_conf_name;
  40         const char *dflt_conf_desc = NULL;
  41         int dflt_conf_node = -ENOENT;
  42
  43         conf = fdt_path_offset(fdt, FIT_CONFS_PATH);
  44         if (conf < 0) {
  45                 debug("%s: Cannot find /configurations node: %d\n", __func__,
  46                       conf);
  47                 return -EINVAL;
  48         }
  49
  50         dflt_conf_name = fdt_getprop(fdt, conf, "default", &len);
  51
  52         for (node = fdt_first_subnode(fdt, conf);
  53              node >= 0;
  54              node = fdt_next_subnode(fdt, node)) {
  55                 name = fdt_getprop(fdt, node, "description", &len);
  56                 if (!name) {
  57 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
  58                         printf("%s: Missing FDT description in DTB\n",
  59                                __func__);
  60 #endif
  61                         return -EINVAL;
  62                 }
  63
  64                 if (dflt_conf_name) {
  65                         const char *node_name = fdt_get_name(fdt, node, NULL);
  66                         if (strcmp(dflt_conf_name, node_name) == 0) {
  67                                 dflt_conf_node = node;
  68                                 dflt_conf_desc = name;
  69                         }
  70                 }
  71
  72                 if (board_fit_config_name_match(name))
  73                         continue;
  74
  75                 debug("Selecting config '%s'\n", name);
  76
  77                 return node;
  78         }
  79
  80         if (dflt_conf_node != -ENOENT) {
  81                 debug("Selecting default config '%s'\n", dflt_conf_desc);
  82                 return dflt_conf_node;
  83         }
  84
  85         return -ENOENT;
  86 }