/* SPDX-License-Identifier: MIT *//* Copyright © 2026 Intel Corporation */ #ifndef _PICK_H_#define _PICK_H_ /* * Given the first two numbers __a and __b of arbitrarily many evenly spaced * numbers, pick the 0-based __index'th value. * * Always prefer this over _PICK() if the numbers are evenly spaced. */#define _PICK_EVEN(__index, __a, __b) ((__a) + (__index) * ((__b) - (__a))) /* * Like _PICK_EVEN(), but supports 2 ranges of evenly spaced address offsets. * @__c_index corresponds to the index in which the second range starts to be * used. Using math interval notation, the first range is used for indexes [ 0, * @__c_index), while the second range is used for [ @__c_index, ... ). Example: * * #define _FOO_A			0xf000 * #define _FOO_B			0xf004 * #define _FOO_C			0xf008 * #define _SUPER_FOO_A			0xa000 * #define _SUPER_FOO_B			0xa100 * #define FOO(x)			_MMIO(_PICK_EVEN_2RANGES(x, 3,		\ *					      _FOO_A, _FOO_B,			\ *					      _SUPER_FOO_A, _SUPER_FOO_B)) * * This expands to: *	0: 0xf000, *	1: 0xf004, *	2: 0xf008, *	3: 0xa000, *	4: 0xa100, *	5: 0xa200, *	... */#define _PICK_EVEN_2RANGES(__index, __c_index, __a, __b, __c, __d)		\	(BUILD_BUG_ON_ZERO(!__is_constexpr(__c_index)) +			\	 ((__index) < (__c_index) ? _PICK_EVEN(__index, __a, __b) :		\				   _PICK_EVEN((__index) - (__c_index), __c, __d))) /* * Given the arbitrary numbers in varargs, pick the 0-based __index'th number. * * Always prefer _PICK_EVEN() over this if the numbers are evenly spaced. */#define _PICK(__index, ...) (((const u32 []){ __VA_ARGS__ })[__index]) #endif