# SPDX-License-Identifier: GPL-2.0+
# Copyright 2018 Google, Inc
# Written by Simon Glass <sjg@chromium.org>
#
# Holds and modifies the state information held by binman
#

import re
from sets import Set

import os
import tools

# Records the device-tree files known to binman, keyed by filename (e.g.
# 'u-boot-spl.dtb')
fdt_files = {}

# Arguments passed to binman to provide arguments to entries
entry_args = {}

# Set of all device tree files references by images
fdt_set = Set()

# Same as above, but excluding the main one
fdt_subset = Set()

# The DTB which contains the full image information
main_dtb = None

def GetFdt(fname):
    """Get the Fdt object for a particular device-tree filename

    Binman keeps track of at least one device-tree file called u-boot.dtb but
    can also have others (e.g. for SPL). This function looks up the given
    filename and returns the associated Fdt object.

    Args:
        fname: Filename to look up (e.g. 'u-boot.dtb').

    Returns:
        Fdt object associated with the filename
    """
    return fdt_files[fname]

def GetFdtPath(fname):
    """Get the full pathname of a particular Fdt object

    Similar to GetFdt() but returns the pathname associated with the Fdt.

    Args:
        fname: Filename to look up (e.g. 'u-boot.dtb').

    Returns:
        Full path name to the associated Fdt
    """
    return fdt_files[fname]._fname

def SetEntryArgs(args):
    """Set the value of the entry args

    This sets up the entry_args dict which is used to supply entry arguments to
    entries.

    Args:
        args: List of entry arguments, each in the format "name=value"
    """
    global entry_args

    entry_args = {}
    if args:
        for arg in args:
            m = re.match('([^=]*)=(.*)', arg)
            if not m:
                raise ValueError("Invalid entry arguemnt '%s'" % arg)
            entry_args[m.group(1)] = m.group(2)

def GetEntryArg(name):
    """Get the value of an entry argument

    Args:
        name: Name of argument to retrieve

    Returns:
        String value of argument
    """
    return entry_args.get(name)

def Prepare(dtb):
    """Get device tree files ready for use

    This sets up a set of device tree files that can be retrieved by GetFdts().
    At present there is only one, that for U-Boot proper.

    Args:
        dtb: Main dtb
    """
    global fdt_set, fdt_subset, fdt_files, main_dtb
    # Import these here in case libfdt.py is not available, in which case
    # the above help option still works.
    import fdt
    import fdt_util

    # If we are updating the DTBs we need to put these updated versions
    # where Entry_blob_dtb can find them. We can ignore 'u-boot.dtb'
    # since it is assumed to be the one passed in with options.dt, and
    # was handled just above.
    main_dtb = dtb
    fdt_files.clear()
    fdt_files['u-boot.dtb'] = dtb
    fdt_set = Set()
    fdt_subset = Set()

def GetFdts():
    """Yield all device tree files being used by binman

    Yields:
        Device trees being used (U-Boot proper, SPL, TPL)
    """
    yield main_dtb