1 /*******************************************************************************
2 
3   Intel 10 Gigabit PCI Express Linux driver
4   Copyright(c) 1999 - 2012 Intel Corporation.
5 
6   This program is free software; you can redistribute it and/or modify it
7   under the terms and conditions of the GNU General Public License,
8   version 2, as published by the Free Software Foundation.
9 
10   This program is distributed in the hope it will be useful, but WITHOUT
11   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13   more details.
14 
15   You should have received a copy of the GNU General Public License along with
16   this program; if not, write to the Free Software Foundation, Inc.,
17   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 
19   The full GNU General Public License is included in this distribution in
20   the file called "COPYING".
21 
22   Contact Information:
23   Linux NICS <linux.nics@intel.com>
24   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
25   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
26 
27 *******************************************************************************/
28 
29 
30 #include "ixgbe.h"
31 #include "ixgbe_type.h"
32 #include "ixgbe_dcb.h"
33 #include "ixgbe_dcb_82598.h"
34 #include "ixgbe_dcb_82599.h"
35 
36 /**
37  * ixgbe_ieee_credits - This calculates the ieee traffic class
38  * credits from the configured bandwidth percentages. Credits
39  * are the smallest unit programmable into the underlying
40  * hardware. The IEEE 802.1Qaz specification do not use bandwidth
41  * groups so this is much simplified from the CEE case.
42  */
ixgbe_ieee_credits(__u8 * bw,__u16 * refill,__u16 * max,int max_frame)43 static s32 ixgbe_ieee_credits(__u8 *bw, __u16 *refill,
44 			      __u16 *max, int max_frame)
45 {
46 	int min_percent = 100;
47 	int min_credit, multiplier;
48 	int i;
49 
50 	min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
51 			DCB_CREDIT_QUANTUM;
52 
53 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
54 		if (bw[i] < min_percent && bw[i])
55 			min_percent = bw[i];
56 	}
57 
58 	multiplier = (min_credit / min_percent) + 1;
59 
60 	/* Find out the hw credits for each TC */
61 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
62 		int val = min(bw[i] * multiplier, MAX_CREDIT_REFILL);
63 
64 		if (val < min_credit)
65 			val = min_credit;
66 		refill[i] = val;
67 
68 		max[i] = bw[i] ? (bw[i] * MAX_CREDIT)/100 : min_credit;
69 	}
70 	return 0;
71 }
72 
73 /**
74  * ixgbe_dcb_calculate_tc_credits - Calculates traffic class credits
75  * @ixgbe_dcb_config: Struct containing DCB settings.
76  * @direction: Configuring either Tx or Rx.
77  *
78  * This function calculates the credits allocated to each traffic class.
79  * It should be called only after the rules are checked by
80  * ixgbe_dcb_check_config().
81  */
ixgbe_dcb_calculate_tc_credits(struct ixgbe_hw * hw,struct ixgbe_dcb_config * dcb_config,int max_frame,u8 direction)82 s32 ixgbe_dcb_calculate_tc_credits(struct ixgbe_hw *hw,
83 				   struct ixgbe_dcb_config *dcb_config,
84 				   int max_frame, u8 direction)
85 {
86 	struct tc_bw_alloc *p;
87 	int min_credit;
88 	int min_multiplier;
89 	int min_percent = 100;
90 	s32 ret_val = 0;
91 	/* Initialization values default for Tx settings */
92 	u32 credit_refill       = 0;
93 	u32 credit_max          = 0;
94 	u16 link_percentage     = 0;
95 	u8  bw_percent          = 0;
96 	u8  i;
97 
98 	if (dcb_config == NULL) {
99 		ret_val = DCB_ERR_CONFIG;
100 		goto out;
101 	}
102 
103 	min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
104 			DCB_CREDIT_QUANTUM;
105 
106 	/* Find smallest link percentage */
107 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
108 		p = &dcb_config->tc_config[i].path[direction];
109 		bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
110 		link_percentage = p->bwg_percent;
111 
112 		link_percentage = (link_percentage * bw_percent) / 100;
113 
114 		if (link_percentage && link_percentage < min_percent)
115 			min_percent = link_percentage;
116 	}
117 
118 	/*
119 	 * The ratio between traffic classes will control the bandwidth
120 	 * percentages seen on the wire. To calculate this ratio we use
121 	 * a multiplier. It is required that the refill credits must be
122 	 * larger than the max frame size so here we find the smallest
123 	 * multiplier that will allow all bandwidth percentages to be
124 	 * greater than the max frame size.
125 	 */
126 	min_multiplier = (min_credit / min_percent) + 1;
127 
128 	/* Find out the link percentage for each TC first */
129 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
130 		p = &dcb_config->tc_config[i].path[direction];
131 		bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
132 
133 		link_percentage = p->bwg_percent;
134 		/* Must be careful of integer division for very small nums */
135 		link_percentage = (link_percentage * bw_percent) / 100;
136 		if (p->bwg_percent > 0 && link_percentage == 0)
137 			link_percentage = 1;
138 
139 		/* Save link_percentage for reference */
140 		p->link_percent = (u8)link_percentage;
141 
142 		/* Calculate credit refill ratio using multiplier */
143 		credit_refill = min(link_percentage * min_multiplier,
144 				    MAX_CREDIT_REFILL);
145 		p->data_credits_refill = (u16)credit_refill;
146 
147 		/* Calculate maximum credit for the TC */
148 		credit_max = (link_percentage * MAX_CREDIT) / 100;
149 
150 		/*
151 		 * Adjustment based on rule checking, if the percentage
152 		 * of a TC is too small, the maximum credit may not be
153 		 * enough to send out a jumbo frame in data plane arbitration.
154 		 */
155 		if (credit_max && (credit_max < min_credit))
156 			credit_max = min_credit;
157 
158 		if (direction == DCB_TX_CONFIG) {
159 			/*
160 			 * Adjustment based on rule checking, if the
161 			 * percentage of a TC is too small, the maximum
162 			 * credit may not be enough to send out a TSO
163 			 * packet in descriptor plane arbitration.
164 			 */
165 			if ((hw->mac.type == ixgbe_mac_82598EB) &&
166 			    credit_max &&
167 			    (credit_max < MINIMUM_CREDIT_FOR_TSO))
168 				credit_max = MINIMUM_CREDIT_FOR_TSO;
169 
170 			dcb_config->tc_config[i].desc_credits_max =
171 				(u16)credit_max;
172 		}
173 
174 		p->data_credits_max = (u16)credit_max;
175 	}
176 
177 out:
178 	return ret_val;
179 }
180 
ixgbe_dcb_unpack_pfc(struct ixgbe_dcb_config * cfg,u8 * pfc_en)181 void ixgbe_dcb_unpack_pfc(struct ixgbe_dcb_config *cfg, u8 *pfc_en)
182 {
183 	int i;
184 
185 	*pfc_en = 0;
186 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++)
187 		*pfc_en |= !!(cfg->tc_config[i].dcb_pfc & 0xF) << i;
188 }
189 
ixgbe_dcb_unpack_refill(struct ixgbe_dcb_config * cfg,int direction,u16 * refill)190 void ixgbe_dcb_unpack_refill(struct ixgbe_dcb_config *cfg, int direction,
191 			     u16 *refill)
192 {
193 	struct tc_bw_alloc *p;
194 	int i;
195 
196 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
197 		p = &cfg->tc_config[i].path[direction];
198 		refill[i] = p->data_credits_refill;
199 	}
200 }
201 
ixgbe_dcb_unpack_max(struct ixgbe_dcb_config * cfg,u16 * max)202 void ixgbe_dcb_unpack_max(struct ixgbe_dcb_config *cfg, u16 *max)
203 {
204 	int i;
205 
206 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++)
207 		max[i] = cfg->tc_config[i].desc_credits_max;
208 }
209 
ixgbe_dcb_unpack_bwgid(struct ixgbe_dcb_config * cfg,int direction,u8 * bwgid)210 void ixgbe_dcb_unpack_bwgid(struct ixgbe_dcb_config *cfg, int direction,
211 			    u8 *bwgid)
212 {
213 	struct tc_bw_alloc *p;
214 	int i;
215 
216 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
217 		p = &cfg->tc_config[i].path[direction];
218 		bwgid[i] = p->bwg_id;
219 	}
220 }
221 
ixgbe_dcb_unpack_prio(struct ixgbe_dcb_config * cfg,int direction,u8 * ptype)222 void ixgbe_dcb_unpack_prio(struct ixgbe_dcb_config *cfg, int direction,
223 			    u8 *ptype)
224 {
225 	struct tc_bw_alloc *p;
226 	int i;
227 
228 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
229 		p = &cfg->tc_config[i].path[direction];
230 		ptype[i] = p->prio_type;
231 	}
232 }
233 
ixgbe_dcb_unpack_map(struct ixgbe_dcb_config * cfg,int direction,u8 * map)234 void ixgbe_dcb_unpack_map(struct ixgbe_dcb_config *cfg, int direction, u8 *map)
235 {
236 	int i, up;
237 	unsigned long bitmap;
238 
239 	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
240 		bitmap = cfg->tc_config[i].path[direction].up_to_tc_bitmap;
241 		for_each_set_bit(up, &bitmap, MAX_USER_PRIORITY)
242 			map[up] = i;
243 	}
244 }
245 
246 /**
247  * ixgbe_dcb_hw_config - Config and enable DCB
248  * @hw: pointer to hardware structure
249  * @dcb_config: pointer to ixgbe_dcb_config structure
250  *
251  * Configure dcb settings and enable dcb mode.
252  */
ixgbe_dcb_hw_config(struct ixgbe_hw * hw,struct ixgbe_dcb_config * dcb_config)253 s32 ixgbe_dcb_hw_config(struct ixgbe_hw *hw,
254                         struct ixgbe_dcb_config *dcb_config)
255 {
256 	s32 ret = 0;
257 	u8 pfc_en;
258 	u8 ptype[MAX_TRAFFIC_CLASS];
259 	u8 bwgid[MAX_TRAFFIC_CLASS];
260 	u8 prio_tc[MAX_TRAFFIC_CLASS];
261 	u16 refill[MAX_TRAFFIC_CLASS];
262 	u16 max[MAX_TRAFFIC_CLASS];
263 
264 	/* Unpack CEE standard containers */
265 	ixgbe_dcb_unpack_pfc(dcb_config, &pfc_en);
266 	ixgbe_dcb_unpack_refill(dcb_config, DCB_TX_CONFIG, refill);
267 	ixgbe_dcb_unpack_max(dcb_config, max);
268 	ixgbe_dcb_unpack_bwgid(dcb_config, DCB_TX_CONFIG, bwgid);
269 	ixgbe_dcb_unpack_prio(dcb_config, DCB_TX_CONFIG, ptype);
270 	ixgbe_dcb_unpack_map(dcb_config, DCB_TX_CONFIG, prio_tc);
271 
272 	switch (hw->mac.type) {
273 	case ixgbe_mac_82598EB:
274 		ret = ixgbe_dcb_hw_config_82598(hw, pfc_en, refill, max,
275 						bwgid, ptype);
276 		break;
277 	case ixgbe_mac_82599EB:
278 	case ixgbe_mac_X540:
279 		ret = ixgbe_dcb_hw_config_82599(hw, pfc_en, refill, max,
280 						bwgid, ptype, prio_tc);
281 		break;
282 	default:
283 		break;
284 	}
285 	return ret;
286 }
287 
288 /* Helper routines to abstract HW specifics from DCB netlink ops */
ixgbe_dcb_hw_pfc_config(struct ixgbe_hw * hw,u8 pfc_en,u8 * prio_tc)289 s32 ixgbe_dcb_hw_pfc_config(struct ixgbe_hw *hw, u8 pfc_en, u8 *prio_tc)
290 {
291 	int ret = -EINVAL;
292 
293 	switch (hw->mac.type) {
294 	case ixgbe_mac_82598EB:
295 		ret = ixgbe_dcb_config_pfc_82598(hw, pfc_en);
296 		break;
297 	case ixgbe_mac_82599EB:
298 	case ixgbe_mac_X540:
299 		ret = ixgbe_dcb_config_pfc_82599(hw, pfc_en, prio_tc);
300 		break;
301 	default:
302 		break;
303 	}
304 	return ret;
305 }
306 
ixgbe_dcb_hw_ets(struct ixgbe_hw * hw,struct ieee_ets * ets,int max_frame)307 s32 ixgbe_dcb_hw_ets(struct ixgbe_hw *hw, struct ieee_ets *ets, int max_frame)
308 {
309 	__u16 refill[IEEE_8021QAZ_MAX_TCS], max[IEEE_8021QAZ_MAX_TCS];
310 	__u8 prio_type[IEEE_8021QAZ_MAX_TCS];
311 	int i;
312 
313 	/* naively give each TC a bwg to map onto CEE hardware */
314 	__u8 bwg_id[IEEE_8021QAZ_MAX_TCS] = {0, 1, 2, 3, 4, 5, 6, 7};
315 
316 	/* Map TSA onto CEE prio type */
317 	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
318 		switch (ets->tc_tsa[i]) {
319 		case IEEE_8021QAZ_TSA_STRICT:
320 			prio_type[i] = 2;
321 			break;
322 		case IEEE_8021QAZ_TSA_ETS:
323 			prio_type[i] = 0;
324 			break;
325 		default:
326 			/* Hardware only supports priority strict or
327 			 * ETS transmission selection algorithms if
328 			 * we receive some other value from dcbnl
329 			 * throw an error
330 			 */
331 			return -EINVAL;
332 		}
333 	}
334 
335 	ixgbe_ieee_credits(ets->tc_tx_bw, refill, max, max_frame);
336 	return ixgbe_dcb_hw_ets_config(hw, refill, max,
337 				       bwg_id, prio_type, ets->prio_tc);
338 }
339 
ixgbe_dcb_hw_ets_config(struct ixgbe_hw * hw,u16 * refill,u16 * max,u8 * bwg_id,u8 * prio_type,u8 * prio_tc)340 s32 ixgbe_dcb_hw_ets_config(struct ixgbe_hw *hw,
341 			    u16 *refill, u16 *max, u8 *bwg_id,
342 			    u8 *prio_type, u8 *prio_tc)
343 {
344 	switch (hw->mac.type) {
345 	case ixgbe_mac_82598EB:
346 		ixgbe_dcb_config_rx_arbiter_82598(hw, refill, max,
347 							prio_type);
348 		ixgbe_dcb_config_tx_desc_arbiter_82598(hw, refill, max,
349 							     bwg_id, prio_type);
350 		ixgbe_dcb_config_tx_data_arbiter_82598(hw, refill, max,
351 							     bwg_id, prio_type);
352 		break;
353 	case ixgbe_mac_82599EB:
354 	case ixgbe_mac_X540:
355 		ixgbe_dcb_config_rx_arbiter_82599(hw, refill, max,
356 						  bwg_id, prio_type, prio_tc);
357 		ixgbe_dcb_config_tx_desc_arbiter_82599(hw, refill, max,
358 						       bwg_id, prio_type);
359 		ixgbe_dcb_config_tx_data_arbiter_82599(hw, refill, max, bwg_id,
360 						       prio_type, prio_tc);
361 		break;
362 	default:
363 		break;
364 	}
365 	return 0;
366 }
367