git.sur5r.net Git - u-boot/blob - arch/arm/cpu/armv8/spin_table.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Socionext Inc.
   4  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
   5  */
   6
   7 #include <common.h>
   8 #include <linux/libfdt.h>
   9 #include <asm/spin_table.h>
  10
  11 int spin_table_update_dt(void *fdt)
  12 {
  13         int cpus_offset, offset;
  14         const char *prop;
  15         int ret;
  16         unsigned long rsv_addr = (unsigned long)&spin_table_reserve_begin;
  17         unsigned long rsv_size = &spin_table_reserve_end -
  18                                                 &spin_table_reserve_begin;
  19
  20         cpus_offset = fdt_path_offset(fdt, "/cpus");
  21         if (cpus_offset < 0)
  22                 return -ENODEV;
  23
  24         for (offset = fdt_first_subnode(fdt, cpus_offset);
  25              offset >= 0;
  26              offset = fdt_next_subnode(fdt, offset)) {
  27                 prop = fdt_getprop(fdt, offset, "device_type", NULL);
  28                 if (!prop || strcmp(prop, "cpu"))
  29                         continue;
  30
  31                 /*
  32                  * In the first loop, we check if every CPU node specifies
  33                  * spin-table.  Otherwise, just return successfully to not
  34                  * disturb other methods, like psci.
  35                  */
  36                 prop = fdt_getprop(fdt, offset, "enable-method", NULL);
  37                 if (!prop || strcmp(prop, "spin-table"))
  38                         return 0;
  39         }
  40
  41         for (offset = fdt_first_subnode(fdt, cpus_offset);
  42              offset >= 0;
  43              offset = fdt_next_subnode(fdt, offset)) {
  44                 prop = fdt_getprop(fdt, offset, "device_type", NULL);
  45                 if (!prop || strcmp(prop, "cpu"))
  46                         continue;
  47
  48                 ret = fdt_setprop_u64(fdt, offset, "cpu-release-addr",
  49                                 (unsigned long)&spin_table_cpu_release_addr);
  50                 if (ret)
  51                         return -ENOSPC;
  52         }
  53
  54         ret = fdt_add_mem_rsv(fdt, rsv_addr, rsv_size);
  55         if (ret)
  56                 return -ENOSPC;
  57
  58         printf("   Reserved memory region for spin-table: addr=%lx size=%lx\n",
  59                rsv_addr, rsv_size);
  60
  61         return 0;
  62 }