1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2020 Intel Corporation
  4 */
  5
  6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  7
  8#include <linux/init.h>
  9#include <linux/module.h>
 10#include <linux/printk.h>
 11
 12/* a tiny module only meant to test
 13 *
 14 *   set/clear_bit
 15 *   get_count_order/long
 16 */
 17
 18/* use an enum because that's the most common BITMAP usage */
 19enum bitops_fun {
 20	BITOPS_4 = 4,
 21	BITOPS_7 = 7,
 22	BITOPS_11 = 11,
 23	BITOPS_31 = 31,
 24	BITOPS_88 = 88,
 25	BITOPS_LAST = 255,
 26	BITOPS_LENGTH = 256
 27};
 28
 29static DECLARE_BITMAP(g_bitmap, BITOPS_LENGTH);
 30
 31static unsigned int order_comb[][2] = {
 32	{0x00000003,  2},
 33	{0x00000004,  2},
 34	{0x00001fff, 13},
 35	{0x00002000, 13},
 36	{0x50000000, 31},
 37	{0x80000000, 31},
 38	{0x80003000, 32},
 39};
 40
 41#ifdef CONFIG_64BIT
 42static unsigned long order_comb_long[][2] = {
 43	{0x0000000300000000, 34},
 44	{0x0000000400000000, 34},
 45	{0x00001fff00000000, 45},
 46	{0x0000200000000000, 45},
 47	{0x5000000000000000, 63},
 48	{0x8000000000000000, 63},
 49	{0x8000300000000000, 64},
 50};
 51#endif
 52
 53static int __init test_bitops_startup(void)
 54{
 55	int i, bit_set;
 56
 57	pr_info("Starting bitops test\n");
 58	set_bit(BITOPS_4, g_bitmap);
 59	set_bit(BITOPS_7, g_bitmap);
 60	set_bit(BITOPS_11, g_bitmap);
 61	set_bit(BITOPS_31, g_bitmap);
 62	set_bit(BITOPS_88, g_bitmap);
 63
 64	for (i = 0; i < ARRAY_SIZE(order_comb); i++) {
 65		if (order_comb[i][1] != get_count_order(order_comb[i][0]))
 66			pr_warn("get_count_order wrong for %x\n",
 67				       order_comb[i][0]);
 68	}
 69
 70	for (i = 0; i < ARRAY_SIZE(order_comb); i++) {
 71		if (order_comb[i][1] != get_count_order_long(order_comb[i][0]))
 72			pr_warn("get_count_order_long wrong for %x\n",
 73				       order_comb[i][0]);
 74	}
 75
 76#ifdef CONFIG_64BIT
 77	for (i = 0; i < ARRAY_SIZE(order_comb_long); i++) {
 78		if (order_comb_long[i][1] !=
 79			       get_count_order_long(order_comb_long[i][0]))
 80			pr_warn("get_count_order_long wrong for %lx\n",
 81				       order_comb_long[i][0]);
 82	}
 83#endif
 84
 85	barrier();
 86
 87	clear_bit(BITOPS_4, g_bitmap);
 88	clear_bit(BITOPS_7, g_bitmap);
 89	clear_bit(BITOPS_11, g_bitmap);
 90	clear_bit(BITOPS_31, g_bitmap);
 91	clear_bit(BITOPS_88, g_bitmap);
 92
 93	bit_set = find_first_bit(g_bitmap, BITOPS_LAST);
 94	if (bit_set != BITOPS_LAST)
 95		pr_err("ERROR: FOUND SET BIT %d\n", bit_set);
 96
 97	pr_info("Completed bitops test\n");
 98
 99	return 0;
100}
101
102static void __exit test_bitops_unstartup(void)
103{
104}
105
106module_init(test_bitops_startup);
107module_exit(test_bitops_unstartup);
108
109MODULE_AUTHOR("Jesse Brandeburg <jesse.brandeburg@intel.com>, Wei Yang <richard.weiyang@gmail.com>");
110MODULE_LICENSE("GPL");
111MODULE_DESCRIPTION("Bit testing module");