drivers/mtd/parsers/ofpart_bcm4908.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2021 Rafał Miłecki <rafal@milecki.pl>
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/init.h>
   8 #include <linux/of.h>
   9 #include <linux/mtd/mtd.h>
  10 #include <linux/slab.h>
  11 #include <linux/mtd/partitions.h>
  12
  13 #include "ofpart_bcm4908.h"
  14
  15 #define BLPARAMS_FW_OFFSET              "NAND_RFS_OFS"
  16
  17 static long long bcm4908_partitions_fw_offset(void)
  18 {
  19         struct device_node *root;
  20         struct property *prop;
  21         const char *s;
  22
  23         root = of_find_node_by_path("/");
  24         if (!root)
  25                 return -ENOENT;
  26
  27         of_property_for_each_string(root, "brcm_blparms", prop, s) {
  28                 size_t len = strlen(BLPARAMS_FW_OFFSET);
  29                 unsigned long offset;
  30                 int err;
  31
  32                 if (strncmp(s, BLPARAMS_FW_OFFSET, len) || s[len] != '=')
  33                         continue;
  34
  35                 err = kstrtoul(s + len + 1, 0, &offset);
  36                 if (err) {
  37                         pr_err("failed to parse %s\n", s + len + 1);
  38                         of_node_put(root);
  39                         return err;
  40                 }
  41
  42                 of_node_put(root);
  43                 return offset << 10;
  44         }
  45
  46         of_node_put(root);
  47         return -ENOENT;
  48 }
  49
  50 int bcm4908_partitions_post_parse(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts)
  51 {
  52         long long fw_offset;
  53         int i;
  54
  55         fw_offset = bcm4908_partitions_fw_offset();
  56
  57         for (i = 0; i < nr_parts; i++) {
  58                 if (of_device_is_compatible(parts[i].of_node, "brcm,bcm4908-firmware")) {
  59                         if (fw_offset < 0 || parts[i].offset == fw_offset)
  60                                 parts[i].name = "firmware";
  61                         else
  62                                 parts[i].name = "backup";
  63                 }
  64         }
  65
  66         return 0;
  67 }