1// SPDX-License-Identifier: GPL-2.0
2/* Copyright(c) 1999 - 2018 Intel Corporation. */
3
4#include "ixgbe.h"
5#include "ixgbe_type.h"
6#include "ixgbe_dcb.h"
7#include "ixgbe_dcb_82598.h"
8#include "ixgbe_dcb_82599.h"
9
10/**
11 * ixgbe_ieee_credits - This calculates the ieee traffic class
12 * credits from the configured bandwidth percentages. Credits
13 * are the smallest unit programmable into the underlying
14 * hardware. The IEEE 802.1Qaz specification do not use bandwidth
15 * groups so this is much simplified from the CEE case.
16 * @bw: bandwidth index by traffic class
17 * @refill: refill credits index by traffic class
18 * @max: max credits by traffic class
19 * @max_frame: maximum frame size
20 */
21static s32 ixgbe_ieee_credits(__u8 *bw, __u16 *refill,
22 __u16 *max, int max_frame)
23{
24 int min_percent = 100;
25 int min_credit, multiplier;
26 int i;
27
28 min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
29 DCB_CREDIT_QUANTUM;
30
31 for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
32 if (bw[i] < min_percent && bw[i])
33 min_percent = bw[i];
34 }
35
36 multiplier = (min_credit / min_percent) + 1;
37
38 /* Find out the hw credits for each TC */
39 for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
40 int val = min(bw[i] * multiplier, MAX_CREDIT_REFILL);
41
42 if (val < min_credit)
43 val = min_credit;
44 refill[i] = val;
45
46 max[i] = bw[i] ? (bw[i] * MAX_CREDIT)/100 : min_credit;
47 }
48 return 0;
49}
50
51/**
52 * ixgbe_dcb_calculate_tc_credits - Calculates traffic class credits
53 * @hw: pointer to hardware structure
54 * @dcb_config: Struct containing DCB settings
55 * @max_frame: Maximum frame size
56 * @direction: Configuring either Tx or Rx
57 *
58 * This function calculates the credits allocated to each traffic class.
59 * It should be called only after the rules are checked by
60 * ixgbe_dcb_check_config().
61 */
62s32 ixgbe_dcb_calculate_tc_credits(struct ixgbe_hw *hw,
63 struct ixgbe_dcb_config *dcb_config,
64 int max_frame, u8 direction)
65{
66 struct tc_bw_alloc *p;
67 int min_credit;
68 int min_multiplier;
69 int min_percent = 100;
70 /* Initialization values default for Tx settings */
71 u32 credit_refill = 0;
72 u32 credit_max = 0;
73 u16 link_percentage = 0;
74 u8 bw_percent = 0;
75 u8 i;
76
77 if (!dcb_config)
78 return DCB_ERR_CONFIG;
79
80 min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
81 DCB_CREDIT_QUANTUM;
82
83 /* Find smallest link percentage */
84 for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
85 p = &dcb_config->tc_config[i].path[direction];
86 bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
87 link_percentage = p->bwg_percent;
88
89 link_percentage = (link_percentage * bw_percent) / 100;
90
91 if (link_percentage && link_percentage < min_percent)
92 min_percent = link_percentage;
93 }
94
95 /*
96 * The ratio between traffic classes will control the bandwidth
97 * percentages seen on the wire. To calculate this ratio we use
98 * a multiplier. It is required that the refill credits must be
99 * larger than the max frame size so here we find the smallest
100 * multiplier that will allow all bandwidth percentages to be
101 * greater than the max frame size.
102 */
103 min_multiplier = (min_credit / min_percent) + 1;
104
105 /* Find out the link percentage for each TC first */
106 for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
107 p = &dcb_config->tc_config[i].path[direction];
108 bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
109
110 link_percentage = p->bwg_percent;
111 /* Must be careful of integer division for very small nums */
112 link_percentage = (link_percentage * bw_percent) / 100;
113 if (p->bwg_percent > 0 && link_percentage == 0)
114 link_percentage = 1;
115
116 /* Save link_percentage for reference */
117 p->link_percent = (u8)link_percentage;
118
119 /* Calculate credit refill ratio using multiplier */
120 credit_refill = min(link_percentage * min_multiplier,
121 MAX_CREDIT_REFILL);
122
123 /* Refill at least minimum credit */
124 if (credit_refill < min_credit)
125 credit_refill = min_credit;
126
127 p->data_credits_refill = (u16)credit_refill;
128
129 /* Calculate maximum credit for the TC */
130 credit_max = (link_percentage * MAX_CREDIT) / 100;
131
132 /*
133 * Adjustment based on rule checking, if the percentage
134 * of a TC is too small, the maximum credit may not be
135 * enough to send out a jumbo frame in data plane arbitration.
136 */
137 if (credit_max < min_credit)
138 credit_max = min_credit;
139
140 if (direction == DCB_TX_CONFIG) {
141 /*
142 * Adjustment based on rule checking, if the
143 * percentage of a TC is too small, the maximum
144 * credit may not be enough to send out a TSO
145 * packet in descriptor plane arbitration.
146 */
147 if ((hw->mac.type == ixgbe_mac_82598EB) &&
148 credit_max &&
149 (credit_max < MINIMUM_CREDIT_FOR_TSO))
150 credit_max = MINIMUM_CREDIT_FOR_TSO;
151
152 dcb_config->tc_config[i].desc_credits_max =
153 (u16)credit_max;
154 }
155
156 p->data_credits_max = (u16)credit_max;
157 }
158
159 return 0;
160}
161
162void ixgbe_dcb_unpack_pfc(struct ixgbe_dcb_config *cfg, u8 *pfc_en)
163{
164 struct tc_configuration *tc_config = &cfg->tc_config[0];
165 int tc;
166
167 for (*pfc_en = 0, tc = 0; tc < MAX_TRAFFIC_CLASS; tc++) {
168 if (tc_config[tc].dcb_pfc != pfc_disabled)
169 *pfc_en |= BIT(tc);
170 }
171}
172
173void ixgbe_dcb_unpack_refill(struct ixgbe_dcb_config *cfg, int direction,
174 u16 *refill)
175{
176 struct tc_configuration *tc_config = &cfg->tc_config[0];
177 int tc;
178
179 for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
180 refill[tc] = tc_config[tc].path[direction].data_credits_refill;
181}
182
183void ixgbe_dcb_unpack_max(struct ixgbe_dcb_config *cfg, u16 *max)
184{
185 struct tc_configuration *tc_config = &cfg->tc_config[0];
186 int tc;
187
188 for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
189 max[tc] = tc_config[tc].desc_credits_max;
190}
191
192void ixgbe_dcb_unpack_bwgid(struct ixgbe_dcb_config *cfg, int direction,
193 u8 *bwgid)
194{
195 struct tc_configuration *tc_config = &cfg->tc_config[0];
196 int tc;
197
198 for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
199 bwgid[tc] = tc_config[tc].path[direction].bwg_id;
200}
201
202void ixgbe_dcb_unpack_prio(struct ixgbe_dcb_config *cfg, int direction,
203 u8 *ptype)
204{
205 struct tc_configuration *tc_config = &cfg->tc_config[0];
206 int tc;
207
208 for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
209 ptype[tc] = tc_config[tc].path[direction].prio_type;
210}
211
212u8 ixgbe_dcb_get_tc_from_up(struct ixgbe_dcb_config *cfg, int direction, u8 up)
213{
214 struct tc_configuration *tc_config = &cfg->tc_config[0];
215 u8 prio_mask = BIT(up);
216 u8 tc = cfg->num_tcs.pg_tcs;
217
218 /* If tc is 0 then DCB is likely not enabled or supported */
219 if (!tc)
220 return 0;
221
222 /*
223 * Test from maximum TC to 1 and report the first match we find. If
224 * we find no match we can assume that the TC is 0 since the TC must
225 * be set for all user priorities
226 */
227 for (tc--; tc; tc--) {
228 if (prio_mask & tc_config[tc].path[direction].up_to_tc_bitmap)
229 break;
230 }
231
232 return tc;
233}
234
235void ixgbe_dcb_unpack_map(struct ixgbe_dcb_config *cfg, int direction, u8 *map)
236{
237 u8 up;
238
239 for (up = 0; up < MAX_USER_PRIORITY; up++)
240 map[up] = ixgbe_dcb_get_tc_from_up(cfg, direction, up);
241}
242
243/**
244 * ixgbe_dcb_hw_config - Config and enable DCB
245 * @hw: pointer to hardware structure
246 * @dcb_config: pointer to ixgbe_dcb_config structure
247 *
248 * Configure dcb settings and enable dcb mode.
249 */
250s32 ixgbe_dcb_hw_config(struct ixgbe_hw *hw,
251 struct ixgbe_dcb_config *dcb_config)
252{
253 u8 pfc_en;
254 u8 ptype[MAX_TRAFFIC_CLASS];
255 u8 bwgid[MAX_TRAFFIC_CLASS];
256 u8 prio_tc[MAX_TRAFFIC_CLASS];
257 u16 refill[MAX_TRAFFIC_CLASS];
258 u16 max[MAX_TRAFFIC_CLASS];
259
260 /* Unpack CEE standard containers */
261 ixgbe_dcb_unpack_pfc(cfg: dcb_config, pfc_en: &pfc_en);
262 ixgbe_dcb_unpack_refill(cfg: dcb_config, DCB_TX_CONFIG, refill);
263 ixgbe_dcb_unpack_max(cfg: dcb_config, max);
264 ixgbe_dcb_unpack_bwgid(cfg: dcb_config, DCB_TX_CONFIG, bwgid);
265 ixgbe_dcb_unpack_prio(cfg: dcb_config, DCB_TX_CONFIG, ptype);
266 ixgbe_dcb_unpack_map(cfg: dcb_config, DCB_TX_CONFIG, map: prio_tc);
267
268 switch (hw->mac.type) {
269 case ixgbe_mac_82598EB:
270 return ixgbe_dcb_hw_config_82598(hw, pfc_en, refill, max,
271 bwg_id: bwgid, prio_type: ptype);
272 case ixgbe_mac_82599EB:
273 case ixgbe_mac_X540:
274 case ixgbe_mac_X550:
275 case ixgbe_mac_X550EM_x:
276 case ixgbe_mac_x550em_a:
277 return ixgbe_dcb_hw_config_82599(hw, pfc_en, refill, max,
278 bwg_id: bwgid, prio_type: ptype, prio_tc);
279 default:
280 break;
281 }
282 return 0;
283}
284
285/* Helper routines to abstract HW specifics from DCB netlink ops */
286s32 ixgbe_dcb_hw_pfc_config(struct ixgbe_hw *hw, u8 pfc_en, u8 *prio_tc)
287{
288 switch (hw->mac.type) {
289 case ixgbe_mac_82598EB:
290 return ixgbe_dcb_config_pfc_82598(hw, pfc_en);
291 case ixgbe_mac_82599EB:
292 case ixgbe_mac_X540:
293 case ixgbe_mac_X550:
294 case ixgbe_mac_X550EM_x:
295 case ixgbe_mac_x550em_a:
296 return ixgbe_dcb_config_pfc_82599(hw, pfc_en, prio_tc);
297 default:
298 break;
299 }
300 return -EINVAL;
301}
302
303s32 ixgbe_dcb_hw_ets(struct ixgbe_hw *hw, struct ieee_ets *ets, int max_frame)
304{
305 __u16 refill[IEEE_8021QAZ_MAX_TCS], max[IEEE_8021QAZ_MAX_TCS];
306 __u8 prio_type[IEEE_8021QAZ_MAX_TCS];
307 int i;
308
309 /* naively give each TC a bwg to map onto CEE hardware */
310 __u8 bwg_id[IEEE_8021QAZ_MAX_TCS] = {0, 1, 2, 3, 4, 5, 6, 7};
311
312 /* Map TSA onto CEE prio type */
313 for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
314 switch (ets->tc_tsa[i]) {
315 case IEEE_8021QAZ_TSA_STRICT:
316 prio_type[i] = 2;
317 break;
318 case IEEE_8021QAZ_TSA_ETS:
319 prio_type[i] = 0;
320 break;
321 default:
322 /* Hardware only supports priority strict or
323 * ETS transmission selection algorithms if
324 * we receive some other value from dcbnl
325 * throw an error
326 */
327 return -EINVAL;
328 }
329 }
330
331 ixgbe_ieee_credits(bw: ets->tc_tx_bw, refill, max, max_frame);
332 return ixgbe_dcb_hw_ets_config(hw, refill, max,
333 bwg_id, prio_type, tc_prio: ets->prio_tc);
334}
335
336s32 ixgbe_dcb_hw_ets_config(struct ixgbe_hw *hw,
337 u16 *refill, u16 *max, u8 *bwg_id,
338 u8 *prio_type, u8 *prio_tc)
339{
340 switch (hw->mac.type) {
341 case ixgbe_mac_82598EB:
342 ixgbe_dcb_config_rx_arbiter_82598(hw, refill, max,
343 prio_type);
344 ixgbe_dcb_config_tx_desc_arbiter_82598(hw, refill, max,
345 bwg_id, prio_type);
346 ixgbe_dcb_config_tx_data_arbiter_82598(hw, refill, max,
347 bwg_id, prio_type);
348 break;
349 case ixgbe_mac_82599EB:
350 case ixgbe_mac_X540:
351 case ixgbe_mac_X550:
352 case ixgbe_mac_X550EM_x:
353 case ixgbe_mac_x550em_a:
354 ixgbe_dcb_config_rx_arbiter_82599(hw, refill, max,
355 bwg_id, prio_type, prio_tc);
356 ixgbe_dcb_config_tx_desc_arbiter_82599(hw, refill, max,
357 bwg_id, prio_type);
358 ixgbe_dcb_config_tx_data_arbiter_82599(hw, refill, max, bwg_id,
359 prio_type, prio_tc);
360 break;
361 default:
362 break;
363 }
364 return 0;
365}
366
367static void ixgbe_dcb_read_rtrup2tc_82599(struct ixgbe_hw *hw, u8 *map)
368{
369 u32 reg, i;
370
371 reg = IXGBE_READ_REG(hw, IXGBE_RTRUP2TC);
372 for (i = 0; i < MAX_USER_PRIORITY; i++)
373 map[i] = IXGBE_RTRUP2TC_UP_MASK &
374 (reg >> (i * IXGBE_RTRUP2TC_UP_SHIFT));
375}
376
377void ixgbe_dcb_read_rtrup2tc(struct ixgbe_hw *hw, u8 *map)
378{
379 switch (hw->mac.type) {
380 case ixgbe_mac_82599EB:
381 case ixgbe_mac_X540:
382 case ixgbe_mac_X550:
383 case ixgbe_mac_X550EM_x:
384 case ixgbe_mac_x550em_a:
385 ixgbe_dcb_read_rtrup2tc_82599(hw, map);
386 break;
387 default:
388 break;
389 }
390}
391

source code of linux/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb.c