Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * MSB0 numbered special bitops handling.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * The bits are numbered:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *   |0..............63|64............127|128...........191|192...........255|
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  * The reason for this bit numbering is the fact that the hardware sets bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  * in a bitmap starting at bit 0 (MSB) and we don't want to scan the bitmap
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  * from the 'wrong end'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/compiler.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/bitops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	const unsigned long *p = addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	unsigned long result = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	unsigned long tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	while (size & ~(BITS_PER_LONG - 1)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 		if ((tmp = *(p++)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 			goto found;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 		result += BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 		size -= BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	if (!size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 		return result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	tmp = (*p) & (~0UL << (BITS_PER_LONG - size));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	if (!tmp)		/* Are any bits set? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		return result + size;	/* Nope. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) found:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	return result + (__fls(tmp) ^ (BITS_PER_LONG - 1));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) EXPORT_SYMBOL(find_first_bit_inv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 				unsigned long offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	const unsigned long *p = addr + (offset / BITS_PER_LONG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	unsigned long result = offset & ~(BITS_PER_LONG - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	unsigned long tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	if (offset >= size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 		return size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	size -= result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	offset %= BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	if (offset) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 		tmp = *(p++);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 		tmp &= (~0UL >> offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 		if (size < BITS_PER_LONG)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 			goto found_first;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 		if (tmp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 			goto found_middle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 		size -= BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 		result += BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	while (size & ~(BITS_PER_LONG-1)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 		if ((tmp = *(p++)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 			goto found_middle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		result += BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 		size -= BITS_PER_LONG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	if (!size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 		return result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	tmp = *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) found_first:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	tmp &= (~0UL << (BITS_PER_LONG - size));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	if (!tmp)		/* Are any bits set? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 		return result + size;	/* Nope. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) found_middle:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 	return result + (__fls(tmp) ^ (BITS_PER_LONG - 1));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) EXPORT_SYMBOL(find_next_bit_inv);