arch/arm/cpu/armv8/spin_table.c

   1 /*
   2  * Copyright (C) 2016 Socionext Inc.
   3  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <libfdt.h>
  10 #include <asm/spin_table.h>
  11
  12 int spin_table_update_dt(void *fdt)
  13 {
  14         int cpus_offset, offset;
  15         const char *prop;
  16         int ret;
  17         unsigned long rsv_addr = (unsigned long)&spin_table_reserve_begin;
  18         unsigned long rsv_size = &spin_table_reserve_end -
  19                                                 &spin_table_reserve_begin;
  20
  21         cpus_offset = fdt_path_offset(fdt, "/cpus");
  22         if (cpus_offset < 0)
  23                 return -ENODEV;
  24
  25         for (offset = fdt_first_subnode(fdt, cpus_offset);
  26              offset >= 0;
  27              offset = fdt_next_subnode(fdt, offset)) {
  28                 prop = fdt_getprop(fdt, offset, "device_type", NULL);
  29                 if (!prop || strcmp(prop, "cpu"))
  30                         continue;
  31
  32                 /*
  33                  * In the first loop, we check if every CPU node specifies
  34                  * spin-table.  Otherwise, just return successfully to not
  35                  * disturb other methods, like psci.
  36                  */
  37                 prop = fdt_getprop(fdt, offset, "enable-method", NULL);
  38                 if (!prop || strcmp(prop, "spin-table"))
  39                         return 0;
  40         }
  41
  42         for (offset = fdt_first_subnode(fdt, cpus_offset);
  43              offset >= 0;
  44              offset = fdt_next_subnode(fdt, offset)) {
  45                 prop = fdt_getprop(fdt, offset, "device_type", NULL);
  46                 if (!prop || strcmp(prop, "cpu"))
  47                         continue;
  48
  49                 ret = fdt_setprop_u64(fdt, offset, "cpu-release-addr",
  50                                 (unsigned long)&spin_table_cpu_release_addr);
  51                 if (ret)
  52                         return -ENOSPC;
  53         }
  54
  55         ret = fdt_add_mem_rsv(fdt, rsv_addr, rsv_size);
  56         if (ret)
  57                 return -ENOSPC;
  58
  59         printf("   Reserved memory region for spin-table: addr=%lx size=%lx\n",
  60                rsv_addr, rsv_size);
  61
  62         return 0;
  63 }