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
12struct 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
32static 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
44struct 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
52struct mlxsw_sp2_kvdl {
53	struct mlxsw_sp2_kvdl_part *parts[MLXSW_SP2_KVDL_PARTS_INFO_LEN];
54};
55
56static 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;
69again:
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
88static 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
107static 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
124static 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
145static 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
157static 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
169static 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
179static struct mlxsw_sp2_kvdl_part *
180mlxsw_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
216static void mlxsw_sp2_kvdl_part_fini(struct mlxsw_sp2_kvdl_part *part)
217{
218	kfree(part);
219}
220
221static 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
238err_kvdl_part_init:
239	for (i--; i >= 0; i--)
240		mlxsw_sp2_kvdl_part_fini(kvdl->parts[i]);
241	return err;
242}
243
244static 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
252static 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
259static 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
266const 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