blob: cfb534e76aea976261e1ca275be77bc9a7cfd832 [file] [log] [blame]
/*
* Copyright 2024 The Hafnium Authors.
*
* Use of this source code is governed by a BSD-style
* license that can be found in the LICENSE file or at
* https://opensource.org/licenses/BSD-3-Clause.
*/
/**
* NOTE: The below macroos use the notation `[hi:lo]` to mean the bits
* from `lo` up-to and including `hi`. This matches the notation used in the
* FF-A specification.
* Examples:
* - bits `[4:0]` of `0xAF` are `1111`,
* - bits `[7:4]` of `0xAF` are `1010`,
* - bits `[31:0]` means the lower half of a 64-bit integer
* - bits `[63:32]` means the upper half of a 64-bit integer
* - bits `[63:0]` means the whole 64-bit integer
*/
/**
* Isolate the `n`th bit of `value`.
*/
#define GET_BIT(value, n) \
__extension__({ \
static_assert((n) < 64, "n out of bounds"); \
((value) & (UINT64_C(1) << (n))); \
})
/**
* Return true if the `n`th bit of `value` is 1.
*/
#define IS_BIT_SET(value, n) (GET_BIT(value, n) != 0)
/**
* Return true if the `n`th bit of `value` is 0.
*/
#define IS_BIT_UNSET(value, n) (GET_BIT(value, n) == 0)
/**
* Return a mask suitable for isolating bits `[hi:lo]` of a 64-bit
* integer.
*/
#define GET_BITS_MASK(hi, lo) \
__extension__({ \
static_assert((hi) < 64, "hi out of bounds"); \
static_assert((hi) >= (lo), "hi must be >= lo"); \
(((~UINT64_C(0)) - (UINT64_C(1) << (lo)) + 1) & \
(~UINT64_C(0) >> (64 - 1 - (hi)))); \
})
/**
* Isolate bits `[hi:lo]` of `value`.
*/
#define GET_BITS(value, hi, lo) ((value) & GET_BITS_MASK(hi, lo))
/**
* Return true if any bits `[lo:hi]` of `value` are 1.
*/
#define ANY_BITS_SET(value, hi, lo) (GET_BITS(value, hi, lo) != 0)
/**
* Return true if all bits `[lo:hi]` of `value` are 1.
*/
#define ALL_BITS_SET(value, hi, lo) \
(GET_BITS(value, hi, lo) == GET_BITS_MASK(hi, lo))
/**
* Return true if any bits `[lo:hi]` of `value` are 0.
*/
#define ANY_BITS_UNSET(value, hi, lo) (!ALL_BITS_SET(value, hi, lo))
/**
* Return true if all bits `[lo:hi]` of `value` are 0.
*/
#define ALL_BITS_UNSET(value, hi, lo) (!ANY_BITS_SET(value, hi, lo))