1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /* Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved */
3 
4 #include <linux/kernel.h>
5 #include <linux/bitops.h>
6 
7 #include "spectrum_cnt.h"
8 
9 #define MLXSW_SP_COUNTER_POOL_BANK_SIZE 4096
10 
11 struct mlxsw_sp_counter_sub_pool {
12 	unsigned int base_index;
13 	unsigned int size;
14 	unsigned int entry_size;
15 	unsigned int bank_count;
16 };
17 
18 struct mlxsw_sp_counter_pool {
19 	unsigned int pool_size;
20 	unsigned long *usage; /* Usage bitmap */
21 	struct mlxsw_sp_counter_sub_pool *sub_pools;
22 };
23 
24 static struct mlxsw_sp_counter_sub_pool mlxsw_sp_counter_sub_pools[] = {
25 	[MLXSW_SP_COUNTER_SUB_POOL_FLOW] = {
26 		.bank_count = 6,
27 	},
28 	[MLXSW_SP_COUNTER_SUB_POOL_RIF] = {
29 		.bank_count = 2,
30 	}
31 };
32 
33 static int mlxsw_sp_counter_pool_validate(struct mlxsw_sp *mlxsw_sp)
34 {
35 	unsigned int total_bank_config = 0;
36 	unsigned int pool_size;
37 	int i;
38 
39 	pool_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, COUNTER_POOL_SIZE);
40 	/* Check config is valid, no bank over subscription */
41 	for (i = 0; i < ARRAY_SIZE(mlxsw_sp_counter_sub_pools); i++)
42 		total_bank_config += mlxsw_sp_counter_sub_pools[i].bank_count;
43 	if (total_bank_config > pool_size / MLXSW_SP_COUNTER_POOL_BANK_SIZE + 1)
44 		return -EINVAL;
45 	return 0;
46 }
47 
48 static int mlxsw_sp_counter_sub_pools_prepare(struct mlxsw_sp *mlxsw_sp)
49 {
50 	struct mlxsw_sp_counter_sub_pool *sub_pool;
51 
52 	/* Prepare generic flow pool*/
53 	sub_pool = &mlxsw_sp_counter_sub_pools[MLXSW_SP_COUNTER_SUB_POOL_FLOW];
54 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, COUNTER_SIZE_PACKETS_BYTES))
55 		return -EIO;
56 	sub_pool->entry_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
57 						  COUNTER_SIZE_PACKETS_BYTES);
58 	/* Prepare erif pool*/
59 	sub_pool = &mlxsw_sp_counter_sub_pools[MLXSW_SP_COUNTER_SUB_POOL_RIF];
60 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, COUNTER_SIZE_ROUTER_BASIC))
61 		return -EIO;
62 	sub_pool->entry_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
63 						  COUNTER_SIZE_ROUTER_BASIC);
64 	return 0;
65 }
66 
67 int mlxsw_sp_counter_pool_init(struct mlxsw_sp *mlxsw_sp)
68 {
69 	struct mlxsw_sp_counter_sub_pool *sub_pool;
70 	struct mlxsw_sp_counter_pool *pool;
71 	unsigned int base_index;
72 	unsigned int map_size;
73 	int i;
74 	int err;
75 
76 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, COUNTER_POOL_SIZE))
77 		return -EIO;
78 
79 	err = mlxsw_sp_counter_pool_validate(mlxsw_sp);
80 	if (err)
81 		return err;
82 
83 	err = mlxsw_sp_counter_sub_pools_prepare(mlxsw_sp);
84 	if (err)
85 		return err;
86 
87 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
88 	if (!pool)
89 		return -ENOMEM;
90 
91 	pool->pool_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, COUNTER_POOL_SIZE);
92 	map_size = BITS_TO_LONGS(pool->pool_size) * sizeof(unsigned long);
93 
94 	pool->usage = kzalloc(map_size, GFP_KERNEL);
95 	if (!pool->usage) {
96 		err = -ENOMEM;
97 		goto err_usage_alloc;
98 	}
99 
100 	pool->sub_pools = mlxsw_sp_counter_sub_pools;
101 	/* Allocation is based on bank count which should be
102 	 * specified for each sub pool statically.
103 	 */
104 	base_index = 0;
105 	for (i = 0; i < ARRAY_SIZE(mlxsw_sp_counter_sub_pools); i++) {
106 		sub_pool = &pool->sub_pools[i];
107 		sub_pool->size = sub_pool->bank_count *
108 				 MLXSW_SP_COUNTER_POOL_BANK_SIZE;
109 		sub_pool->base_index = base_index;
110 		base_index += sub_pool->size;
111 		/* The last bank can't be fully used */
112 		if (sub_pool->base_index + sub_pool->size > pool->pool_size)
113 			sub_pool->size = pool->pool_size - sub_pool->base_index;
114 	}
115 
116 	mlxsw_sp->counter_pool = pool;
117 	return 0;
118 
119 err_usage_alloc:
120 	kfree(pool);
121 	return err;
122 }
123 
124 void mlxsw_sp_counter_pool_fini(struct mlxsw_sp *mlxsw_sp)
125 {
126 	struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
127 
128 	WARN_ON(find_first_bit(pool->usage, pool->pool_size) !=
129 			       pool->pool_size);
130 	kfree(pool->usage);
131 	kfree(pool);
132 }
133 
134 int mlxsw_sp_counter_alloc(struct mlxsw_sp *mlxsw_sp,
135 			   enum mlxsw_sp_counter_sub_pool_id sub_pool_id,
136 			   unsigned int *p_counter_index)
137 {
138 	struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
139 	struct mlxsw_sp_counter_sub_pool *sub_pool;
140 	unsigned int entry_index;
141 	unsigned int stop_index;
142 	int i;
143 
144 	sub_pool = &mlxsw_sp_counter_sub_pools[sub_pool_id];
145 	stop_index = sub_pool->base_index + sub_pool->size;
146 	entry_index = sub_pool->base_index;
147 
148 	entry_index = find_next_zero_bit(pool->usage, stop_index, entry_index);
149 	if (entry_index == stop_index)
150 		return -ENOBUFS;
151 	/* The sub-pools can contain non-integer number of entries
152 	 * so we must check for overflow
153 	 */
154 	if (entry_index + sub_pool->entry_size > stop_index)
155 		return -ENOBUFS;
156 	for (i = 0; i < sub_pool->entry_size; i++)
157 		__set_bit(entry_index + i, pool->usage);
158 
159 	*p_counter_index = entry_index;
160 	return 0;
161 }
162 
163 void mlxsw_sp_counter_free(struct mlxsw_sp *mlxsw_sp,
164 			   enum mlxsw_sp_counter_sub_pool_id sub_pool_id,
165 			   unsigned int counter_index)
166 {
167 	struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
168 	struct mlxsw_sp_counter_sub_pool *sub_pool;
169 	int i;
170 
171 	if (WARN_ON(counter_index >= pool->pool_size))
172 		return;
173 	sub_pool = &mlxsw_sp_counter_sub_pools[sub_pool_id];
174 	for (i = 0; i < sub_pool->entry_size; i++)
175 		__clear_bit(counter_index + i, pool->usage);
176 }
177