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 int 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 */
62int 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 */
250int 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(dcb_config, &pfc_en);
262	ixgbe_dcb_unpack_refill(dcb_config, DCB_TX_CONFIG, refill);
263	ixgbe_dcb_unpack_max(dcb_config, max);
264	ixgbe_dcb_unpack_bwgid(dcb_config, DCB_TX_CONFIG, bwgid);
265	ixgbe_dcb_unpack_prio(dcb_config, DCB_TX_CONFIG, ptype);
266	ixgbe_dcb_unpack_map(dcb_config, DCB_TX_CONFIG, 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						 bwgid, 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						 bwgid, ptype, prio_tc);
279	default:
280		break;
281	}
282	return 0;
283}
284
285/* Helper routines to abstract HW specifics from DCB netlink ops */
286int 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
303int 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(ets->tc_tx_bw, refill, max, max_frame);
332	return ixgbe_dcb_hw_ets_config(hw, refill, max,
333				       bwg_id, prio_type, ets->prio_tc);
334}
335
336int 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