arch/arm/cpu/armv7/virt-dt.c

   1 /*
   2  * Copyright (C) 2013 - ARM Ltd
   3  * Author: Marc Zyngier <marc.zyngier@arm.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <common.h>
  19 #include <stdio_dev.h>
  20 #include <linux/ctype.h>
  21 #include <linux/types.h>
  22 #include <asm/global_data.h>
  23 #include <libfdt.h>
  24 #include <fdt_support.h>
  25 #include <asm/armv7.h>
  26 #include <asm/psci.h>
  27
  28 static int fdt_psci(void *fdt)
  29 {
  30 #ifdef CONFIG_ARMV7_PSCI
  31         int nodeoff;
  32         int tmp;
  33
  34         nodeoff = fdt_path_offset(fdt, "/cpus");
  35         if (nodeoff < 0) {
  36                 printf("couldn't find /cpus\n");
  37                 return nodeoff;
  38         }
  39
  40         /* add 'enable-method = "psci"' to each cpu node */
  41         for (tmp = fdt_first_subnode(fdt, nodeoff);
  42              tmp >= 0;
  43              tmp = fdt_next_subnode(fdt, tmp)) {
  44                 const struct fdt_property *prop;
  45                 int len;
  46
  47                 prop = fdt_get_property(fdt, tmp, "device_type", &len);
  48                 if (!prop)
  49                         continue;
  50                 if (len < 4)
  51                         continue;
  52                 if (strcmp(prop->data, "cpu"))
  53                         continue;
  54
  55                 fdt_setprop_string(fdt, tmp, "enable-method", "psci");
  56         }
  57
  58         nodeoff = fdt_path_offset(fdt, "/psci");
  59         if (nodeoff < 0) {
  60                 nodeoff = fdt_path_offset(fdt, "/");
  61                 if (nodeoff < 0)
  62                         return nodeoff;
  63
  64                 nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
  65                 if (nodeoff < 0)
  66                         return nodeoff;
  67         }
  68
  69         tmp = fdt_setprop_string(fdt, nodeoff, "compatible", "arm,psci");
  70         if (tmp)
  71                 return tmp;
  72         tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
  73         if (tmp)
  74                 return tmp;
  75         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend", ARM_PSCI_FN_CPU_SUSPEND);
  76         if (tmp)
  77                 return tmp;
  78         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off", ARM_PSCI_FN_CPU_OFF);
  79         if (tmp)
  80                 return tmp;
  81         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on", ARM_PSCI_FN_CPU_ON);
  82         if (tmp)
  83                 return tmp;
  84         tmp = fdt_setprop_u32(fdt, nodeoff, "migrate", ARM_PSCI_FN_MIGRATE);
  85         if (tmp)
  86                 return tmp;
  87 #endif
  88         return 0;
  89 }
  90
  91 int armv7_update_dt(void *fdt)
  92 {
  93 #ifndef CONFIG_ARMV7_SECURE_BASE
  94         /* secure code lives in RAM, keep it alive */
  95         fdt_add_mem_rsv(fdt, (unsigned long)__secure_start,
  96                         __secure_end - __secure_start);
  97 #endif
  98
  99         return fdt_psci(fdt);
 100 }