| /* 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 |