{
  "name": "gsp_ctrl",
  "size": 392,
  "fields": [
    {"name": "magic",         "offset": 0,   "fmt": "u32", "note": "GSP-like control block magic 0x47535031"},
    {"name": "version",       "offset": 4,   "fmt": "u32"},
    {"name": "state",         "offset": 8,   "fmt": "u32", "enum": {"0": "S0", "1": "S1", "2": "S2", "3": "S3"}},
    {"name": "heartbeat",     "offset": 12,  "fmt": "u32"},
    {"name": "rpc_count",     "offset": 16,  "fmt": "u64"},
    {"name": "last_rpc",      "offset": 24,  "fmt": "u64"},
    {"name": "mailbox",       "offset": 32,  "fmt": "u64", "enum": {"0": "idle", "1": "PING", "2": "ECHO", "3": "FILL", "4": "SUM", "5": "STATE", "6": "FAULT"}},
    {"name": "arg0",          "offset": 40,  "fmt": "u64"},
    {"name": "arg1",          "offset": 48,  "fmt": "u64"},
    {"name": "result",        "offset": 56,  "fmt": "u64"},
    {"name": "buf",           "offset": 64,  "fmt": "bytes", "size": 256},
    {"name": "handler_count", "offset": 320, "fmt": "u64"},
    {"name": "handlers",      "offset": 328, "fmt": "u64", "count": 8}
  ]
}