xref: /linux/drivers/net/ethernet/mellanox/mlxsw/spectrum2_kvdl.c (revision b8265621f4888af9494e1d685620871ec81bc33d)
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 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(TNUMT, 0x29, KVD_SIZE, KVD_SIZE),
39 };
40 
41 #define MLXSW_SP2_KVDL_PARTS_INFO_LEN ARRAY_SIZE(mlxsw_sp2_kvdl_parts_info)
42 
43 struct mlxsw_sp2_kvdl_part {
44 	const struct mlxsw_sp2_kvdl_part_info *info;
45 	unsigned int usage_bit_count;
46 	unsigned int indexes_per_usage_bit;
47 	unsigned int last_allocated_bit;
48 	unsigned long usage[];	/* Usage bits */
49 };
50 
51 struct mlxsw_sp2_kvdl {
52 	struct mlxsw_sp2_kvdl_part *parts[MLXSW_SP2_KVDL_PARTS_INFO_LEN];
53 };
54 
55 static int mlxsw_sp2_kvdl_part_find_zero_bits(struct mlxsw_sp2_kvdl_part *part,
56 					      unsigned int bit_count,
57 					      unsigned int *p_bit)
58 {
59 	unsigned int start_bit;
60 	unsigned int bit;
61 	unsigned int i;
62 	bool wrap = false;
63 
64 	start_bit = part->last_allocated_bit + 1;
65 	if (start_bit == part->usage_bit_count)
66 		start_bit = 0;
67 	bit = start_bit;
68 again:
69 	bit = find_next_zero_bit(part->usage, part->usage_bit_count, bit);
70 	if (!wrap && bit + bit_count >= part->usage_bit_count) {
71 		wrap = true;
72 		bit = 0;
73 		goto again;
74 	}
75 	if (wrap && bit + bit_count >= start_bit)
76 		return -ENOBUFS;
77 	for (i = 0; i < bit_count; i++) {
78 		if (test_bit(bit + i, part->usage)) {
79 			bit += bit_count;
80 			goto again;
81 		}
82 	}
83 	*p_bit = bit;
84 	return 0;
85 }
86 
87 static int mlxsw_sp2_kvdl_part_alloc(struct mlxsw_sp2_kvdl_part *part,
88 				     unsigned int size,
89 				     u32 *p_kvdl_index)
90 {
91 	unsigned int bit_count;
92 	unsigned int bit;
93 	unsigned int i;
94 	int err;
95 
96 	bit_count = DIV_ROUND_UP(size, part->indexes_per_usage_bit);
97 	err = mlxsw_sp2_kvdl_part_find_zero_bits(part, bit_count, &bit);
98 	if (err)
99 		return err;
100 	for (i = 0; i < bit_count; i++)
101 		__set_bit(bit + i, part->usage);
102 	*p_kvdl_index = bit * part->indexes_per_usage_bit;
103 	return 0;
104 }
105 
106 static int mlxsw_sp2_kvdl_rec_del(struct mlxsw_sp *mlxsw_sp, u8 res_type,
107 				  u16 size, u32 kvdl_index)
108 {
109 	char *iedr_pl;
110 	int err;
111 
112 	iedr_pl = kmalloc(MLXSW_REG_IEDR_LEN, GFP_KERNEL);
113 	if (!iedr_pl)
114 		return -ENOMEM;
115 
116 	mlxsw_reg_iedr_pack(iedr_pl);
117 	mlxsw_reg_iedr_rec_pack(iedr_pl, 0, res_type, size, kvdl_index);
118 	err = mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(iedr), iedr_pl);
119 	kfree(iedr_pl);
120 	return err;
121 }
122 
123 static void mlxsw_sp2_kvdl_part_free(struct mlxsw_sp *mlxsw_sp,
124 				     struct mlxsw_sp2_kvdl_part *part,
125 				     unsigned int size, u32 kvdl_index)
126 {
127 	unsigned int bit_count;
128 	unsigned int bit;
129 	unsigned int i;
130 	int err;
131 
132 	/* We need to ask FW to delete previously used KVD linear index */
133 	err = mlxsw_sp2_kvdl_rec_del(mlxsw_sp, part->info->res_type,
134 				     size, kvdl_index);
135 	if (err)
136 		return;
137 
138 	bit_count = DIV_ROUND_UP(size, part->indexes_per_usage_bit);
139 	bit = kvdl_index / part->indexes_per_usage_bit;
140 	for (i = 0; i < bit_count; i++)
141 		__clear_bit(bit + i, part->usage);
142 }
143 
144 static int mlxsw_sp2_kvdl_alloc(struct mlxsw_sp *mlxsw_sp, void *priv,
145 				enum mlxsw_sp_kvdl_entry_type type,
146 				unsigned int entry_count,
147 				u32 *p_entry_index)
148 {
149 	unsigned int size = entry_count * mlxsw_sp_kvdl_entry_size(type);
150 	struct mlxsw_sp2_kvdl *kvdl = priv;
151 	struct mlxsw_sp2_kvdl_part *part = kvdl->parts[type];
152 
153 	return mlxsw_sp2_kvdl_part_alloc(part, size, p_entry_index);
154 }
155 
156 static void mlxsw_sp2_kvdl_free(struct mlxsw_sp *mlxsw_sp, void *priv,
157 				enum mlxsw_sp_kvdl_entry_type type,
158 				unsigned int entry_count,
159 				int entry_index)
160 {
161 	unsigned int size = entry_count * mlxsw_sp_kvdl_entry_size(type);
162 	struct mlxsw_sp2_kvdl *kvdl = priv;
163 	struct mlxsw_sp2_kvdl_part *part = kvdl->parts[type];
164 
165 	return mlxsw_sp2_kvdl_part_free(mlxsw_sp, part, size, entry_index);
166 }
167 
168 static int mlxsw_sp2_kvdl_alloc_size_query(struct mlxsw_sp *mlxsw_sp,
169 					   void *priv,
170 					   enum mlxsw_sp_kvdl_entry_type type,
171 					   unsigned int entry_count,
172 					   unsigned int *p_alloc_count)
173 {
174 	*p_alloc_count = entry_count;
175 	return 0;
176 }
177 
178 static struct mlxsw_sp2_kvdl_part *
179 mlxsw_sp2_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
180 			 const struct mlxsw_sp2_kvdl_part_info *info)
181 {
182 	unsigned int indexes_per_usage_bit;
183 	struct mlxsw_sp2_kvdl_part *part;
184 	unsigned int index_range;
185 	unsigned int usage_bit_count;
186 	size_t usage_size;
187 
188 	if (!mlxsw_core_res_valid(mlxsw_sp->core,
189 				  info->usage_bit_count_res_id) ||
190 	    !mlxsw_core_res_valid(mlxsw_sp->core,
191 				  info->index_range_res_id))
192 		return ERR_PTR(-EIO);
193 	usage_bit_count = mlxsw_core_res_get(mlxsw_sp->core,
194 					     info->usage_bit_count_res_id);
195 	index_range = mlxsw_core_res_get(mlxsw_sp->core,
196 					 info->index_range_res_id);
197 
198 	/* For some partitions, one usage bit represents a group of indexes.
199 	 * That's why we compute the number of indexes per usage bit here,
200 	 * according to queried resources.
201 	 */
202 	indexes_per_usage_bit = index_range / usage_bit_count;
203 
204 	usage_size = BITS_TO_LONGS(usage_bit_count) * sizeof(unsigned long);
205 	part = kzalloc(sizeof(*part) + usage_size, GFP_KERNEL);
206 	if (!part)
207 		return ERR_PTR(-ENOMEM);
208 	part->info = info;
209 	part->usage_bit_count = usage_bit_count;
210 	part->indexes_per_usage_bit = indexes_per_usage_bit;
211 	part->last_allocated_bit = usage_bit_count - 1;
212 	return part;
213 }
214 
215 static void mlxsw_sp2_kvdl_part_fini(struct mlxsw_sp2_kvdl_part *part)
216 {
217 	kfree(part);
218 }
219 
220 static int mlxsw_sp2_kvdl_parts_init(struct mlxsw_sp *mlxsw_sp,
221 				     struct mlxsw_sp2_kvdl *kvdl)
222 {
223 	const struct mlxsw_sp2_kvdl_part_info *info;
224 	int i;
225 	int err;
226 
227 	for (i = 0; i < MLXSW_SP2_KVDL_PARTS_INFO_LEN; i++) {
228 		info = &mlxsw_sp2_kvdl_parts_info[i];
229 		kvdl->parts[i] = mlxsw_sp2_kvdl_part_init(mlxsw_sp, info);
230 		if (IS_ERR(kvdl->parts[i])) {
231 			err = PTR_ERR(kvdl->parts[i]);
232 			goto err_kvdl_part_init;
233 		}
234 	}
235 	return 0;
236 
237 err_kvdl_part_init:
238 	for (i--; i >= 0; i--)
239 		mlxsw_sp2_kvdl_part_fini(kvdl->parts[i]);
240 	return err;
241 }
242 
243 static void mlxsw_sp2_kvdl_parts_fini(struct mlxsw_sp2_kvdl *kvdl)
244 {
245 	int i;
246 
247 	for (i = 0; i < MLXSW_SP2_KVDL_PARTS_INFO_LEN; i++)
248 		mlxsw_sp2_kvdl_part_fini(kvdl->parts[i]);
249 }
250 
251 static int mlxsw_sp2_kvdl_init(struct mlxsw_sp *mlxsw_sp, void *priv)
252 {
253 	struct mlxsw_sp2_kvdl *kvdl = priv;
254 
255 	return mlxsw_sp2_kvdl_parts_init(mlxsw_sp, kvdl);
256 }
257 
258 static void mlxsw_sp2_kvdl_fini(struct mlxsw_sp *mlxsw_sp, void *priv)
259 {
260 	struct mlxsw_sp2_kvdl *kvdl = priv;
261 
262 	mlxsw_sp2_kvdl_parts_fini(kvdl);
263 }
264 
265 const struct mlxsw_sp_kvdl_ops mlxsw_sp2_kvdl_ops = {
266 	.priv_size = sizeof(struct mlxsw_sp2_kvdl),
267 	.init = mlxsw_sp2_kvdl_init,
268 	.fini = mlxsw_sp2_kvdl_fini,
269 	.alloc = mlxsw_sp2_kvdl_alloc,
270 	.free = mlxsw_sp2_kvdl_free,
271 	.alloc_size_query = mlxsw_sp2_kvdl_alloc_size_query,
272 };
273