arch/arm/lib/psci-dt.c

   1 /*
   2  * Copyright 2016 NXP Semiconductor, Inc.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <libfdt.h>
   9 #include <fdt_support.h>
  10 #include <linux/sizes.h>
  11 #include <linux/kernel.h>
  12 #include <asm/psci.h>
  13 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
  14 #include <asm/armv8/sec_firmware.h>
  15 #endif
  16
  17 int fdt_psci(void *fdt)
  18 {
  19 #if defined(CONFIG_ARMV8_PSCI) || defined(CONFIG_ARMV7_PSCI)
  20         int nodeoff;
  21         unsigned int psci_ver = 0;
  22         char *psci_compt;
  23         int tmp;
  24
  25         nodeoff = fdt_path_offset(fdt, "/cpus");
  26         if (nodeoff < 0) {
  27                 printf("couldn't find /cpus\n");
  28                 return nodeoff;
  29         }
  30
  31         /* add 'enable-method = "psci"' to each cpu node */
  32         for (tmp = fdt_first_subnode(fdt, nodeoff);
  33              tmp >= 0;
  34              tmp = fdt_next_subnode(fdt, tmp)) {
  35                 const struct fdt_property *prop;
  36                 int len;
  37
  38                 prop = fdt_get_property(fdt, tmp, "device_type", &len);
  39                 if (!prop)
  40                         continue;
  41                 if (len < 4)
  42                         continue;
  43                 if (strcmp(prop->data, "cpu"))
  44                         continue;
  45
  46                 /*
  47                  * Not checking rv here, our approach is to skip over errors in
  48                  * individual cpu nodes, hopefully some of the nodes are
  49                  * processed correctly and those will boot
  50                  */
  51                 fdt_setprop_string(fdt, tmp, "enable-method", "psci");
  52         }
  53
  54         nodeoff = fdt_path_offset(fdt, "/psci");
  55         if (nodeoff >= 0)
  56                 goto init_psci_node;
  57
  58         nodeoff = fdt_path_offset(fdt, "/");
  59         if (nodeoff < 0)
  60                 return nodeoff;
  61
  62         nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
  63         if (nodeoff < 0)
  64                 return nodeoff;
  65
  66 init_psci_node:
  67 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
  68         psci_ver = sec_firmware_support_psci_version();
  69 #endif
  70         switch (psci_ver) {
  71         case 0x00010000:
  72                 psci_compt = "arm,psci-1.0";
  73                 break;
  74         case 0x00000002:
  75                 psci_compt = "arm,psci-0.2";
  76                 break;
  77         default:
  78                 psci_compt = "arm,psci";
  79                 break;
  80         }
  81
  82         tmp = fdt_setprop_string(fdt, nodeoff, "compatible", psci_compt);
  83         if (tmp)
  84                 return tmp;
  85         tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
  86         if (tmp)
  87                 return tmp;
  88
  89 #ifdef CONFIG_ARMV7_PSCI
  90         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
  91                                 ARM_PSCI_FN_CPU_SUSPEND);
  92         if (tmp)
  93                 return tmp;
  94         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off", ARM_PSCI_FN_CPU_OFF);
  95         if (tmp)
  96                 return tmp;
  97         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on", ARM_PSCI_FN_CPU_ON);
  98         if (tmp)
  99                 return tmp;
 100         tmp = fdt_setprop_u32(fdt, nodeoff, "migrate", ARM_PSCI_FN_MIGRATE);
 101         if (tmp)
 102                 return tmp;
 103 #endif
 104 #endif
 105         return 0;
 106 }