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         /*
  55          * The PSCI node might be called "/psci" or might be called something
  56          * else but contain either of the compatible strings
  57          * "arm,psci"/"arm,psci-0.2"
  58          */
  59         nodeoff = fdt_path_offset(fdt, "/psci");
  60         if (nodeoff >= 0)
  61                 goto init_psci_node;
  62
  63         nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci");
  64         if (nodeoff >= 0)
  65                 goto init_psci_node;
  66
  67         nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci-0.2");
  68         if (nodeoff >= 0)
  69                 goto init_psci_node;
  70
  71         nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci-1.0");
  72         if (nodeoff >= 0)
  73                 goto init_psci_node;
  74
  75         nodeoff = fdt_path_offset(fdt, "/");
  76         if (nodeoff < 0)
  77                 return nodeoff;
  78
  79         nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
  80         if (nodeoff < 0)
  81                 return nodeoff;
  82
  83 init_psci_node:
  84 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
  85         psci_ver = sec_firmware_support_psci_version();
  86 #endif
  87         switch (psci_ver) {
  88         case 0x00010000:
  89                 psci_compt = "arm,psci-1.0";
  90                 break;
  91         case 0x00000002:
  92                 psci_compt = "arm,psci-0.2";
  93                 break;
  94         default:
  95                 psci_compt = "arm,psci";
  96                 break;
  97         }
  98
  99         tmp = fdt_setprop_string(fdt, nodeoff, "compatible", psci_compt);
 100         if (tmp)
 101                 return tmp;
 102         tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
 103         if (tmp)
 104                 return tmp;
 105
 106 #ifdef CONFIG_ARMV7_PSCI
 107         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
 108                                 ARM_PSCI_FN_CPU_SUSPEND);
 109         if (tmp)
 110                 return tmp;
 111         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off", ARM_PSCI_FN_CPU_OFF);
 112         if (tmp)
 113                 return tmp;
 114         tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on", ARM_PSCI_FN_CPU_ON);
 115         if (tmp)
 116                 return tmp;
 117         tmp = fdt_setprop_u32(fdt, nodeoff, "migrate", ARM_PSCI_FN_MIGRATE);
 118         if (tmp)
 119                 return tmp;
 120 #endif
 121 #endif
 122         return 0;
 123 }