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