xref: /freebsd/sys/dev/ena/ena_rss.c (revision 8a271827e7b5d5310e06df1f9f49ba0ef9efd263)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2015-2021 Amazon.com, Inc. or its affiliates.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  *
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_rss.h"
38 
39 #include "ena_rss.h"
40 
41 /*
42  * This function should generate unique key for the whole driver.
43  * If the key was already genereated in the previous call (for example
44  * for another adapter), then it should be returned instead.
45  */
46 void
47 ena_rss_key_fill(void *key, size_t size)
48 {
49 	static bool key_generated;
50 	static uint8_t default_key[ENA_HASH_KEY_SIZE];
51 
52 	KASSERT(size <= ENA_HASH_KEY_SIZE,
53 	    ("Requested more bytes than ENA RSS key can hold"));
54 
55 	if (!key_generated) {
56 		arc4random_buf(default_key, ENA_HASH_KEY_SIZE);
57 		key_generated = true;
58 	}
59 
60 	memcpy(key, default_key, size);
61 }
62 
63 /*
64  * ENA HW expects the key to be in reverse-byte order.
65  */
66 static void
67 ena_rss_reorder_hash_key(u8 *reordered_key, const u8 *key, size_t key_size)
68 {
69 	int i;
70 
71 	key = key + key_size - 1;
72 
73 	for (i = 0; i < key_size; ++i)
74 		*reordered_key++ = *key--;
75 }
76 
77 int
78 ena_rss_set_hash(struct ena_com_dev *ena_dev, const u8 *key)
79 {
80 	enum ena_admin_hash_functions ena_func = ENA_ADMIN_TOEPLITZ;
81 	u8 hw_key[ENA_HASH_KEY_SIZE];
82 
83 	ena_rss_reorder_hash_key(hw_key, key, ENA_HASH_KEY_SIZE);
84 
85 	return (ena_com_fill_hash_function(ena_dev, ena_func, hw_key,
86 	    ENA_HASH_KEY_SIZE, 0x0));
87 }
88 
89 int
90 ena_rss_get_hash_key(struct ena_com_dev *ena_dev, u8 *key)
91 {
92 	u8 hw_key[ENA_HASH_KEY_SIZE];
93 	int rc;
94 
95 	rc = ena_com_get_hash_key(ena_dev, hw_key);
96 	if (rc != 0)
97 		return rc;
98 
99 	ena_rss_reorder_hash_key(key, hw_key, ENA_HASH_KEY_SIZE);
100 
101 	return (0);
102 }
103 
104 static int
105 ena_rss_init_default(struct ena_adapter *adapter)
106 {
107 	struct ena_com_dev *ena_dev = adapter->ena_dev;
108 	device_t dev = adapter->pdev;
109 	int qid, rc, i;
110 
111 	rc = ena_com_rss_init(ena_dev, ENA_RX_RSS_TABLE_LOG_SIZE);
112 	if (unlikely(rc != 0)) {
113 		ena_log(dev, ERR, "Cannot init indirect table\n");
114 		return (rc);
115 	}
116 
117 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; i++) {
118 #ifdef RSS
119 		qid = rss_get_indirection_to_bucket(i) % adapter->num_io_queues;
120 #else
121 		qid = i % adapter->num_io_queues;
122 #endif
123 		rc = ena_com_indirect_table_fill_entry(ena_dev, i,
124 		    ENA_IO_RXQ_IDX(qid));
125 		if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
126 			ena_log(dev, ERR, "Cannot fill indirect table\n");
127 			goto err_rss_destroy;
128 		}
129 	}
130 
131 
132 #ifdef RSS
133 	uint8_t rss_algo = rss_gethashalgo();
134 	if (rss_algo == RSS_HASH_TOEPLITZ) {
135 		uint8_t hash_key[RSS_KEYSIZE];
136 
137 		rss_getkey(hash_key);
138 		rc = ena_rss_set_hash(ena_dev, hash_key);
139 	} else
140 #endif
141 		rc = ena_com_fill_hash_function(ena_dev, ENA_ADMIN_TOEPLITZ,
142 		    NULL, ENA_HASH_KEY_SIZE, 0x0);
143 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
144 		ena_log(dev, ERR, "Cannot fill hash function\n");
145 		goto err_rss_destroy;
146 	}
147 
148 	rc = ena_com_set_default_hash_ctrl(ena_dev);
149 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
150 		ena_log(dev, ERR, "Cannot fill hash control\n");
151 		goto err_rss_destroy;
152 	}
153 
154 	rc = ena_rss_indir_init(adapter);
155 
156 	return (rc == EOPNOTSUPP ? 0 : rc);
157 
158 err_rss_destroy:
159 	ena_com_rss_destroy(ena_dev);
160 	return (rc);
161 }
162 
163 /* Configure the Rx forwarding */
164 int
165 ena_rss_configure(struct ena_adapter *adapter)
166 {
167 	struct ena_com_dev *ena_dev = adapter->ena_dev;
168 	int rc;
169 
170 	/* In case the RSS table was destroyed */
171 	if (!ena_dev->rss.tbl_log_size) {
172 		rc = ena_rss_init_default(adapter);
173 		if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
174 			ena_log(adapter->pdev, ERR,
175 			    "WARNING: RSS was not properly re-initialized,"
176 			    " it will affect bandwidth\n");
177 			ENA_FLAG_CLEAR_ATOMIC(ENA_FLAG_RSS_ACTIVE, adapter);
178 			return (rc);
179 		}
180 	}
181 
182 	/* Set indirect table */
183 	rc = ena_com_indirect_table_set(ena_dev);
184 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
185 		return (rc);
186 
187 	/* Configure hash function (if supported) */
188 	rc = ena_com_set_hash_function(ena_dev);
189 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
190 		return (rc);
191 
192 	/* Configure hash inputs (if supported) */
193 	rc = ena_com_set_hash_ctrl(ena_dev);
194 	if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
195 		return (rc);
196 
197 	return (0);
198 }
199 
200 static void
201 ena_rss_init_default_deferred(void *arg)
202 {
203 	struct ena_adapter *adapter;
204 	devclass_t dc;
205 	int max;
206 	int rc;
207 
208 	dc = devclass_find("ena");
209 	if (unlikely(dc == NULL)) {
210 		ena_log_raw(ERR, "SYSINIT: %s: No devclass ena\n", __func__);
211 		return;
212 	}
213 
214 	max = devclass_get_maxunit(dc);
215 	while (max-- >= 0) {
216 		adapter = devclass_get_softc(dc, max);
217 		if (adapter != NULL) {
218 			rc = ena_rss_init_default(adapter);
219 			ENA_FLAG_SET_ATOMIC(ENA_FLAG_RSS_ACTIVE, adapter);
220 			if (unlikely(rc != 0)) {
221 				ena_log(adapter->pdev, WARN,
222 				    "WARNING: RSS was not properly initialized,"
223 				    " it will affect bandwidth\n");
224 				ENA_FLAG_CLEAR_ATOMIC(ENA_FLAG_RSS_ACTIVE,
225 				    adapter);
226 			}
227 		}
228 	}
229 }
230 SYSINIT(ena_rss_init, SI_SUB_KICK_SCHEDULER, SI_ORDER_SECOND,
231     ena_rss_init_default_deferred, NULL);
232 
233 int
234 ena_rss_indir_get(struct ena_adapter *adapter, uint32_t *table)
235 {
236 	int rc, i;
237 
238 	rc = ena_com_indirect_table_get(adapter->ena_dev, table);
239 	if (rc != 0) {
240 		if (rc == EOPNOTSUPP)
241 			device_printf(adapter->pdev,
242 			    "Reading from indirection table not supported\n");
243 		else
244 			device_printf(adapter->pdev,
245 			    "Unable to get indirection table\n");
246 		return (rc);
247 	}
248 
249 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; ++i)
250 		table[i] = ENA_IO_RXQ_IDX_TO_COMBINED_IDX(table[i]);
251 
252 	return (0);
253 }
254 
255 int
256 ena_rss_indir_set(struct ena_adapter *adapter, uint32_t *table)
257 {
258 	int rc, i;
259 
260 	for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; ++i) {
261 		rc = ena_com_indirect_table_fill_entry(adapter->ena_dev, i,
262 		    ENA_IO_RXQ_IDX(table[i]));
263 		if (rc != 0) {
264 			device_printf(adapter->pdev,
265 			    "Cannot fill indirection table entry %d\n", i);
266 			return (rc);
267 		}
268 	}
269 
270 	rc = ena_com_indirect_table_set(adapter->ena_dev);
271 	if (rc == EOPNOTSUPP)
272 		device_printf(adapter->pdev,
273 		    "Writing to indirection table not supported\n");
274 	else if (rc != 0)
275 		device_printf(adapter->pdev, "Cannot set indirection table\n");
276 
277 	return (rc);
278 }
279 
280 int
281 ena_rss_indir_init(struct ena_adapter *adapter)
282 {
283 	struct ena_indir *indir = adapter->rss_indir;
284 	int rc;
285 
286 	if (indir == NULL) {
287 		adapter->rss_indir = indir = malloc(sizeof(struct ena_indir),
288 		    M_DEVBUF, M_WAITOK | M_ZERO);
289 		if (indir == NULL)
290 			return (ENOMEM);
291 	}
292 
293 	rc = ena_rss_indir_get(adapter, indir->table);
294 	if (rc != 0) {
295 		free(adapter->rss_indir, M_DEVBUF);
296 		adapter->rss_indir = NULL;
297 
298 		return (rc);
299 	}
300 
301 	ena_rss_copy_indir_buf(indir->sysctl_buf, indir->table);
302 
303 	return (0);
304 }
305