from construct import *

DEVTREE_HEADER_SIGNATURE = "odtr3"

DEVTREE_HEADER = Struct(
    "signature" / PaddedString(8, "ascii"),
    "revision" / Int32ul,
    "flags" / Int32ul,
    "entries_count" / Int32ul,
    "name_list_offset" / Int32ul
)

DEVTREE_ENTRY_FLAGS_MMIO = (1 << 0)
DEVTREE_ENTRY_TYPE_IO = 0
DEVTREE_ENTRY_TYPE_FB = 1
DEVTREE_ENTRY_TYPE_UART = 2
DEVTREE_ENTRY_TYPE_RAM = 3
DEVTREE_ENTRY_TYPE_STORAGE = 4
DEVTREE_ENTRY_TYPE_BUS_CONTROLLER = 5
DEVTREE_ENTRY_TYPE_RTC = 6

# Currently flags maps to irq_flags_t in the kernel.
# Later we might need to enhance irq_flags_from_devtree() to use as translator.
DEVTREE_IRQ_FLAGS_EDGE_TRIGGER = (1 << 0)

DEVTREE_ENTRY = Struct(
    "type" / Int32ul,
    "flags" / Int32ul,
    "region_base" / Int64ul,
    "region_size" / Int64ul,
    "irq_lane" / Int32ul,
    "irq_flags" / Int32ul,
    "irq_priority" / Int32ul,
    "rel_name_offset" / Int32ul,
    "aux1" / Int64ul,
    "aux2" / Int64ul,
    "aux3" / Int64ul,
    "aux4" / Int64ul,
)