arm-tzc 0.2.1

Arm TrustZone Address Space Controller
Documentation 
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// SPDX-FileCopyrightText: Copyright The arm-tzc Contributors.
// SPDX-License-Identifier: MIT OR Apache-2.0

#[inline(always)]
/// Extracts from `value` the bits in the range `lsb..=end`.
pub(crate) const fn extract_bits(value: u32, msb: u32, lsb: u32) -> u32 {
    (value >> lsb) & ((1 << (msb - lsb + 1)) - 1)
}

#[inline(always)]
/// Extracts the bit at the given position. Equivalent to `extract_bits(value, position, position)`.
pub(crate) const fn get_bit(value: u32, position: usize) -> bool {
    value >> position & 0b1 == 1
}

#[inline(always)]
/// Sets the bit at `position` to the given state.
pub(crate) const fn set_bit(value: &mut u32, position: usize, bit: bool) {
    if bit {
        *value |= 1 << position;
    } else {
        *value &= !(1 << position);
    }
}

#[inline(always)]
/// Performs a bitwise concatenation of two `u32` into a single `u64`. This is the opposite
/// operation of [`split_address`].
pub(crate) const fn concatenate_address_parts(low: u32, high: u32) -> u64 {
    (high as u64) << 32 | low as u64
}

#[inline(always)]
/// Perform a bitwise split of a `u64` into two `u32`. This is the opposite operation of
/// [`concatenate_address_parts`].
pub(crate) fn split_address(address: u64) -> (u32, u32) {
    ((address & u32::MAX as u64) as u32, (address >> 32) as u32)
}