xref: /linux/drivers/net/ethernet/mellanox/mlxsw/spectrum2_kvdl.c (revision 9e56ff53b4115875667760445b028357848b4748)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /* Copyright (c) 2018 Mellanox Technologies. All rights reserved */
3 
4 #include <linux/kernel.h>
5 #include <linux/bitops.h>
6 
7 #include "spectrum.h"
8 #include "core.h"
9 #include "reg.h"
10 #include "resources.h"
11 
12 struct mlxsw_sp2_kvdl_part_info {
13 	u8 res_type;
14 	/* For each defined partititon we need to know how many
15 	 * usage bits we need and how many indexes there are
16 	 * represented by a single bit. This could be got from FW
17 	 * querying appropriate resources. So have the resource
18 	 * ids for this purpose in partition definition.
19 	 */
20 	enum mlxsw_res_id usage_bit_count_res_id;
21 	enum mlxsw_res_id index_range_res_id;
22 };
23 
24 #define MLXSW_SP2_KVDL_PART_INFO(_entry_type, _res_type,			\
25 				 _usage_bit_count_res_id, _index_range_res_id)	\
26 [MLXSW_SP_KVDL_ENTRY_TYPE_##_entry_type] = {					\
27 	.res_type = _res_type,							\
28 	.usage_bit_count_res_id = MLXSW_RES_ID_##_usage_bit_count_res_id,	\
29 	.index_range_res_id = MLXSW_RES_ID_##_index_range_res_id,		\
30 }
31 
32 static const struct mlxsw_sp2_kvdl_part_info mlxsw_sp2_kvdl_parts_info[] = {
33 	MLXSW_SP2_KVDL_PART_INFO(ADJ, 0x21, KVD_SIZE, MAX_KVD_LINEAR_RANGE),
34 	MLXSW_SP2_KVDL_PART_INFO(ACTSET, 0x23, MAX_KVD_ACTION_SETS,
35 				 MAX_KVD_ACTION_SETS),
36 	MLXSW_SP2_KVDL_PART_INFO(PBS, 0x24, KVD_SIZE, KVD_SIZE),
37 	MLXSW_SP2_KVDL_PART_INFO(MCRIGR, 0x26, KVD_SIZE, KVD_SIZE),
38 	MLXSW_SP2_KVDL_PART_INFO(IPV6_ADDRESS, 0x28, KVD_SIZE, KVD_SIZE),
39 	MLXSW_SP2_KVDL_PART_INFO(TNUMT, 0x29, KVD_SIZE, KVD_SIZE),
40 };
41 
42 #define MLXSW_SP2_KVDL_PARTS_INFO_LEN ARRAY_SIZE(mlxsw_sp2_kvdl_parts_info)
43 
44 struct mlxsw_sp2_kvdl_part {
45 	const struct mlxsw_sp2_kvdl_part_info *info;
46 	unsigned int usage_bit_count;
47 	unsigned int indexes_per_usage_bit;
48 	unsigned int last_allocated_bit;
49 	unsigned long usage[];	/* Usage bits */
50 };
51 
52 struct mlxsw_sp2_kvdl {
53 	struct mlxsw_sp2_kvdl_part *parts[MLXSW_SP2_KVDL_PARTS_INFO_LEN];
54 };
55 
56 static int mlxsw_sp2_kvdl_part_find_zero_bits(struct mlxsw_sp2_kvdl_part *part,
57 					      unsigned int bit_count,
58 					      unsigned int *p_bit)
59 {
60 	unsigned int start_bit;
61 	unsigned int bit;
62 	unsigned int i;
63 	bool wrap = false;
64 
65 	start_bit = part->last_allocated_bit + 1;
66 	if (start_bit == part->usage_bit_count)
67 		start_bit = 0;
68 	bit = start_bit;
69 again:
70 	bit = find_next_zero_bit(part->usage, part->usage_bit_count, bit);
71 	if (!wrap && bit + bit_count >= part->usage_bit_count) {
72 		wrap = true;
73 		bit = 0;
74 		goto again;
75 	}
76 	if (wrap && bit + bit_count >= start_bit)
77 		return -ENOBUFS;
78 	for (i = 0; i < bit_count; i++) {
79 		if (test_bit(bit + i, part->usage)) {
80 			bit += bit_count;
81 			goto again;
82 		}
83 	}
84 	*p_bit = bit;
85 	return 0;
86 }
87 
88 static int mlxsw_sp2_kvdl_part_alloc(struct mlxsw_sp2_kvdl_part *part,
89 				     unsigned int size,
90 				     u32 *p_kvdl_index)
91 {
92 	unsigned int bit_count;
93 	unsigned int bit;
94 	unsigned int i;
95 	int err;
96 
97 	bit_count = DIV_ROUND_UP(size, part->indexes_per_usage_bit);
98 	err = mlxsw_sp2_kvdl_part_find_zero_bits(part, bit_count, &bit);
99 	if (err)
100 		return err;
101 	for (i = 0; i < bit_count; i++)
102 		__set_bit(bit + i, part->usage);
103 	*p_kvdl_index = bit * part->indexes_per_usage_bit;
104 	return 0;
105 }
106 
107 static int mlxsw_sp2_kvdl_rec_del(struct mlxsw_sp *mlxsw_sp, u8 res_type,
108 				  u16 size, u32 kvdl_index)
109 {
110 	char *iedr_pl;
111 	int err;
112 
113 	iedr_pl = kmalloc(MLXSW_REG_IEDR_LEN, GFP_KERNEL);
114 	if (!iedr_pl)
115 		return -ENOMEM;
116 
117 	mlxsw_reg_iedr_pack(iedr_pl);
118 	mlxsw_reg_iedr_rec_pack(iedr_pl, 0, res_type, size, kvdl_index);
119 	err = mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(iedr), iedr_pl);
120 	kfree(iedr_pl);
121 	return err;
122 }
123 
124 static void mlxsw_sp2_kvdl_part_free(struct mlxsw_sp *mlxsw_sp,
125 				     struct mlxsw_sp2_kvdl_part *part,
126 				     unsigned int size, u32 kvdl_index)
127 {
128 	unsigned int bit_count;
129 	unsigned int bit;
130 	unsigned int i;
131 	int err;
132 
133 	/* We need to ask FW to delete previously used KVD linear index */
134 	err = mlxsw_sp2_kvdl_rec_del(mlxsw_sp, part->info->res_type,
135 				     size, kvdl_index);
136 	if (err)
137 		return;
138 
139 	bit_count = DIV_ROUND_UP(size, part->indexes_per_usage_bit);
140 	bit = kvdl_index / part->indexes_per_usage_bit;
141 	for (i = 0; i < bit_count; i++)
142 		__clear_bit(bit + i, part->usage);
143 }
144 
145 static int mlxsw_sp2_kvdl_alloc(struct mlxsw_sp *mlxsw_sp, void *priv,
146 				enum mlxsw_sp_kvdl_entry_type type,
147 				unsigned int entry_count,
148 				u32 *p_entry_index)
149 {
150 	unsigned int size = entry_count * mlxsw_sp_kvdl_entry_size(type);
151 	struct mlxsw_sp2_kvdl *kvdl = priv;
152 	struct mlxsw_sp2_kvdl_part *part = kvdl->parts[type];
153 
154 	return mlxsw_sp2_kvdl_part_alloc(part, size, p_entry_index);
155 }
156 
157 static void mlxsw_sp2_kvdl_free(struct mlxsw_sp *mlxsw_sp, void *priv,
158 				enum mlxsw_sp_kvdl_entry_type type,
159 				unsigned int entry_count,
160 				int entry_index)
161 {
162 	unsigned int size = entry_count * mlxsw_sp_kvdl_entry_size(type);
163 	struct mlxsw_sp2_kvdl *kvdl = priv;
164 	struct mlxsw_sp2_kvdl_part *part = kvdl->parts[type];
165 
166 	return mlxsw_sp2_kvdl_part_free(mlxsw_sp, part, size, entry_index);
167 }
168 
169 static int mlxsw_sp2_kvdl_alloc_size_query(struct mlxsw_sp *mlxsw_sp,
170 					   void *priv,
171 					   enum mlxsw_sp_kvdl_entry_type type,
172 					   unsigned int entry_count,
173 					   unsigned int *p_alloc_count)
174 {
175 	*p_alloc_count = entry_count;
176 	return 0;
177 }
178 
179 static struct mlxsw_sp2_kvdl_part *
180 mlxsw_sp2_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
181 			 const struct mlxsw_sp2_kvdl_part_info *info)
182 {
183 	unsigned int indexes_per_usage_bit;
184 	struct mlxsw_sp2_kvdl_part *part;
185 	unsigned int index_range;
186 	unsigned int usage_bit_count;
187 	size_t usage_size;
188 
189 	if (!mlxsw_core_res_valid(mlxsw_sp->core,
190 				  info->usage_bit_count_res_id) ||
191 	    !mlxsw_core_res_valid(mlxsw_sp->core,
192 				  info->index_range_res_id))
193 		return ERR_PTR(-EIO);
194 	usage_bit_count = mlxsw_core_res_get(mlxsw_sp->core,
195 					     info->usage_bit_count_res_id);
196 	index_range = mlxsw_core_res_get(mlxsw_sp->core,
197 					 info->index_range_res_id);
198 
199 	/* For some partitions, one usage bit represents a group of indexes.
200 	 * That's why we compute the number of indexes per usage bit here,
201 	 * according to queried resources.
202 	 */
203 	indexes_per_usage_bit = index_range / usage_bit_count;
204 
205 	usage_size = BITS_TO_LONGS(usage_bit_count) * sizeof(unsigned long);
206 	part = kzalloc(sizeof(*part) + usage_size, GFP_KERNEL);
207 	if (!part)
208 		return ERR_PTR(-ENOMEM);
209 	part->info = info;
210 	part->usage_bit_count = usage_bit_count;
211 	part->indexes_per_usage_bit = indexes_per_usage_bit;
212 	part->last_allocated_bit = usage_bit_count - 1;
213 	return part;
214 }
215 
216 static void mlxsw_sp2_kvdl_part_fini(struct mlxsw_sp2_kvdl_part *part)
217 {
218 	kfree(part);
219 }
220 
221 static int mlxsw_sp2_kvdl_parts_init(struct mlxsw_sp *mlxsw_sp,
222 				     struct mlxsw_sp2_kvdl *kvdl)
223 {
224 	const struct mlxsw_sp2_kvdl_part_info *info;
225 	int i;
226 	int err;
227 
228 	for (i = 0; i < MLXSW_SP2_KVDL_PARTS_INFO_LEN; i++) {
229 		info = &mlxsw_sp2_kvdl_parts_info[i];
230 		kvdl->parts[i] = mlxsw_sp2_kvdl_part_init(mlxsw_sp, info);
231 		if (IS_ERR(kvdl->parts[i])) {
232 			err = PTR_ERR(kvdl->parts[i]);
233 			goto err_kvdl_part_init;
234 		}
235 	}
236 	return 0;
237 
238 err_kvdl_part_init:
239 	for (i--; i >= 0; i--)
240 		mlxsw_sp2_kvdl_part_fini(kvdl->parts[i]);
241 	return err;
242 }
243 
244 static void mlxsw_sp2_kvdl_parts_fini(struct mlxsw_sp2_kvdl *kvdl)
245 {
246 	int i;
247 
248 	for (i = 0; i < MLXSW_SP2_KVDL_PARTS_INFO_LEN; i++)
249 		mlxsw_sp2_kvdl_part_fini(kvdl->parts[i]);
250 }
251 
252 static int mlxsw_sp2_kvdl_init(struct mlxsw_sp *mlxsw_sp, void *priv)
253 {
254 	struct mlxsw_sp2_kvdl *kvdl = priv;
255 
256 	return mlxsw_sp2_kvdl_parts_init(mlxsw_sp, kvdl);
257 }
258 
259 static void mlxsw_sp2_kvdl_fini(struct mlxsw_sp *mlxsw_sp, void *priv)
260 {
261 	struct mlxsw_sp2_kvdl *kvdl = priv;
262 
263 	mlxsw_sp2_kvdl_parts_fini(kvdl);
264 }
265 
266 const struct mlxsw_sp_kvdl_ops mlxsw_sp2_kvdl_ops = {
267 	.priv_size = sizeof(struct mlxsw_sp2_kvdl),
268 	.init = mlxsw_sp2_kvdl_init,
269 	.fini = mlxsw_sp2_kvdl_fini,
270 	.alloc = mlxsw_sp2_kvdl_alloc,
271 	.free = mlxsw_sp2_kvdl_free,
272 	.alloc_size_query = mlxsw_sp2_kvdl_alloc_size_query,
273 };
274