1/*******************************************************************************
2
3  Intel 10 Gigabit PCI Express Linux driver
4  Copyright(c) 1999 - 2014 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 */
43static 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 */
82s32 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	/* Initialization values default for Tx settings */
91	u32 credit_refill       = 0;
92	u32 credit_max          = 0;
93	u16 link_percentage     = 0;
94	u8  bw_percent          = 0;
95	u8  i;
96
97	if (!dcb_config)
98		return DCB_ERR_CONFIG;
99
100	min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
101			DCB_CREDIT_QUANTUM;
102
103	/* Find smallest link percentage */
104	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
105		p = &dcb_config->tc_config[i].path[direction];
106		bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
107		link_percentage = p->bwg_percent;
108
109		link_percentage = (link_percentage * bw_percent) / 100;
110
111		if (link_percentage && link_percentage < min_percent)
112			min_percent = link_percentage;
113	}
114
115	/*
116	 * The ratio between traffic classes will control the bandwidth
117	 * percentages seen on the wire. To calculate this ratio we use
118	 * a multiplier. It is required that the refill credits must be
119	 * larger than the max frame size so here we find the smallest
120	 * multiplier that will allow all bandwidth percentages to be
121	 * greater than the max frame size.
122	 */
123	min_multiplier = (min_credit / min_percent) + 1;
124
125	/* Find out the link percentage for each TC first */
126	for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
127		p = &dcb_config->tc_config[i].path[direction];
128		bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
129
130		link_percentage = p->bwg_percent;
131		/* Must be careful of integer division for very small nums */
132		link_percentage = (link_percentage * bw_percent) / 100;
133		if (p->bwg_percent > 0 && link_percentage == 0)
134			link_percentage = 1;
135
136		/* Save link_percentage for reference */
137		p->link_percent = (u8)link_percentage;
138
139		/* Calculate credit refill ratio using multiplier */
140		credit_refill = min(link_percentage * min_multiplier,
141				    MAX_CREDIT_REFILL);
142		p->data_credits_refill = (u16)credit_refill;
143
144		/* Calculate maximum credit for the TC */
145		credit_max = (link_percentage * MAX_CREDIT) / 100;
146
147		/*
148		 * Adjustment based on rule checking, if the percentage
149		 * of a TC is too small, the maximum credit may not be
150		 * enough to send out a jumbo frame in data plane arbitration.
151		 */
152		if (credit_max && (credit_max < min_credit))
153			credit_max = min_credit;
154
155		if (direction == DCB_TX_CONFIG) {
156			/*
157			 * Adjustment based on rule checking, if the
158			 * percentage of a TC is too small, the maximum
159			 * credit may not be enough to send out a TSO
160			 * packet in descriptor plane arbitration.
161			 */
162			if ((hw->mac.type == ixgbe_mac_82598EB) &&
163			    credit_max &&
164			    (credit_max < MINIMUM_CREDIT_FOR_TSO))
165				credit_max = MINIMUM_CREDIT_FOR_TSO;
166
167			dcb_config->tc_config[i].desc_credits_max =
168				(u16)credit_max;
169		}
170
171		p->data_credits_max = (u16)credit_max;
172	}
173
174	return 0;
175}
176
177void ixgbe_dcb_unpack_pfc(struct ixgbe_dcb_config *cfg, u8 *pfc_en)
178{
179	struct tc_configuration *tc_config = &cfg->tc_config[0];
180	int tc;
181
182	for (*pfc_en = 0, tc = 0; tc < MAX_TRAFFIC_CLASS; tc++) {
183		if (tc_config[tc].dcb_pfc != pfc_disabled)
184			*pfc_en |= 1 << tc;
185	}
186}
187
188void ixgbe_dcb_unpack_refill(struct ixgbe_dcb_config *cfg, int direction,
189			     u16 *refill)
190{
191	struct tc_configuration *tc_config = &cfg->tc_config[0];
192	int tc;
193
194	for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
195		refill[tc] = tc_config[tc].path[direction].data_credits_refill;
196}
197
198void ixgbe_dcb_unpack_max(struct ixgbe_dcb_config *cfg, u16 *max)
199{
200	struct tc_configuration *tc_config = &cfg->tc_config[0];
201	int tc;
202
203	for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
204		max[tc] = tc_config[tc].desc_credits_max;
205}
206
207void ixgbe_dcb_unpack_bwgid(struct ixgbe_dcb_config *cfg, int direction,
208			    u8 *bwgid)
209{
210	struct tc_configuration *tc_config = &cfg->tc_config[0];
211	int tc;
212
213	for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
214		bwgid[tc] = tc_config[tc].path[direction].bwg_id;
215}
216
217void ixgbe_dcb_unpack_prio(struct ixgbe_dcb_config *cfg, int direction,
218			    u8 *ptype)
219{
220	struct tc_configuration *tc_config = &cfg->tc_config[0];
221	int tc;
222
223	for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
224		ptype[tc] = tc_config[tc].path[direction].prio_type;
225}
226
227u8 ixgbe_dcb_get_tc_from_up(struct ixgbe_dcb_config *cfg, int direction, u8 up)
228{
229	struct tc_configuration *tc_config = &cfg->tc_config[0];
230	u8 prio_mask = 1 << up;
231	u8 tc = cfg->num_tcs.pg_tcs;
232
233	/* If tc is 0 then DCB is likely not enabled or supported */
234	if (!tc)
235		return 0;
236
237	/*
238	 * Test from maximum TC to 1 and report the first match we find.  If
239	 * we find no match we can assume that the TC is 0 since the TC must
240	 * be set for all user priorities
241	 */
242	for (tc--; tc; tc--) {
243		if (prio_mask & tc_config[tc].path[direction].up_to_tc_bitmap)
244			break;
245	}
246
247	return tc;
248}
249
250void ixgbe_dcb_unpack_map(struct ixgbe_dcb_config *cfg, int direction, u8 *map)
251{
252	u8 up;
253
254	for (up = 0; up < MAX_USER_PRIORITY; up++)
255		map[up] = ixgbe_dcb_get_tc_from_up(cfg, direction, up);
256}
257
258/**
259 * ixgbe_dcb_hw_config - Config and enable DCB
260 * @hw: pointer to hardware structure
261 * @dcb_config: pointer to ixgbe_dcb_config structure
262 *
263 * Configure dcb settings and enable dcb mode.
264 */
265s32 ixgbe_dcb_hw_config(struct ixgbe_hw *hw,
266			struct ixgbe_dcb_config *dcb_config)
267{
268	u8 pfc_en;
269	u8 ptype[MAX_TRAFFIC_CLASS];
270	u8 bwgid[MAX_TRAFFIC_CLASS];
271	u8 prio_tc[MAX_TRAFFIC_CLASS];
272	u16 refill[MAX_TRAFFIC_CLASS];
273	u16 max[MAX_TRAFFIC_CLASS];
274
275	/* Unpack CEE standard containers */
276	ixgbe_dcb_unpack_pfc(dcb_config, &pfc_en);
277	ixgbe_dcb_unpack_refill(dcb_config, DCB_TX_CONFIG, refill);
278	ixgbe_dcb_unpack_max(dcb_config, max);
279	ixgbe_dcb_unpack_bwgid(dcb_config, DCB_TX_CONFIG, bwgid);
280	ixgbe_dcb_unpack_prio(dcb_config, DCB_TX_CONFIG, ptype);
281	ixgbe_dcb_unpack_map(dcb_config, DCB_TX_CONFIG, prio_tc);
282
283	switch (hw->mac.type) {
284	case ixgbe_mac_82598EB:
285		return ixgbe_dcb_hw_config_82598(hw, pfc_en, refill, max,
286						 bwgid, ptype);
287	case ixgbe_mac_82599EB:
288	case ixgbe_mac_X540:
289	case ixgbe_mac_X550:
290	case ixgbe_mac_X550EM_x:
291		return ixgbe_dcb_hw_config_82599(hw, pfc_en, refill, max,
292						 bwgid, ptype, prio_tc);
293	default:
294		break;
295	}
296	return 0;
297}
298
299/* Helper routines to abstract HW specifics from DCB netlink ops */
300s32 ixgbe_dcb_hw_pfc_config(struct ixgbe_hw *hw, u8 pfc_en, u8 *prio_tc)
301{
302	switch (hw->mac.type) {
303	case ixgbe_mac_82598EB:
304		return ixgbe_dcb_config_pfc_82598(hw, pfc_en);
305	case ixgbe_mac_82599EB:
306	case ixgbe_mac_X540:
307	case ixgbe_mac_X550:
308	case ixgbe_mac_X550EM_x:
309		return ixgbe_dcb_config_pfc_82599(hw, pfc_en, prio_tc);
310	default:
311		break;
312	}
313	return -EINVAL;
314}
315
316s32 ixgbe_dcb_hw_ets(struct ixgbe_hw *hw, struct ieee_ets *ets, int max_frame)
317{
318	__u16 refill[IEEE_8021QAZ_MAX_TCS], max[IEEE_8021QAZ_MAX_TCS];
319	__u8 prio_type[IEEE_8021QAZ_MAX_TCS];
320	int i;
321
322	/* naively give each TC a bwg to map onto CEE hardware */
323	__u8 bwg_id[IEEE_8021QAZ_MAX_TCS] = {0, 1, 2, 3, 4, 5, 6, 7};
324
325	/* Map TSA onto CEE prio type */
326	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
327		switch (ets->tc_tsa[i]) {
328		case IEEE_8021QAZ_TSA_STRICT:
329			prio_type[i] = 2;
330			break;
331		case IEEE_8021QAZ_TSA_ETS:
332			prio_type[i] = 0;
333			break;
334		default:
335			/* Hardware only supports priority strict or
336			 * ETS transmission selection algorithms if
337			 * we receive some other value from dcbnl
338			 * throw an error
339			 */
340			return -EINVAL;
341		}
342	}
343
344	ixgbe_ieee_credits(ets->tc_tx_bw, refill, max, max_frame);
345	return ixgbe_dcb_hw_ets_config(hw, refill, max,
346				       bwg_id, prio_type, ets->prio_tc);
347}
348
349s32 ixgbe_dcb_hw_ets_config(struct ixgbe_hw *hw,
350			    u16 *refill, u16 *max, u8 *bwg_id,
351			    u8 *prio_type, u8 *prio_tc)
352{
353	switch (hw->mac.type) {
354	case ixgbe_mac_82598EB:
355		ixgbe_dcb_config_rx_arbiter_82598(hw, refill, max,
356							prio_type);
357		ixgbe_dcb_config_tx_desc_arbiter_82598(hw, refill, max,
358							     bwg_id, prio_type);
359		ixgbe_dcb_config_tx_data_arbiter_82598(hw, refill, max,
360							     bwg_id, prio_type);
361		break;
362	case ixgbe_mac_82599EB:
363	case ixgbe_mac_X540:
364	case ixgbe_mac_X550:
365	case ixgbe_mac_X550EM_x:
366		ixgbe_dcb_config_rx_arbiter_82599(hw, refill, max,
367						  bwg_id, prio_type, prio_tc);
368		ixgbe_dcb_config_tx_desc_arbiter_82599(hw, refill, max,
369						       bwg_id, prio_type);
370		ixgbe_dcb_config_tx_data_arbiter_82599(hw, refill, max, bwg_id,
371						       prio_type, prio_tc);
372		break;
373	default:
374		break;
375	}
376	return 0;
377}
378
379static void ixgbe_dcb_read_rtrup2tc_82599(struct ixgbe_hw *hw, u8 *map)
380{
381	u32 reg, i;
382
383	reg = IXGBE_READ_REG(hw, IXGBE_RTRUP2TC);
384	for (i = 0; i < MAX_USER_PRIORITY; i++)
385		map[i] = IXGBE_RTRUP2TC_UP_MASK &
386			(reg >> (i * IXGBE_RTRUP2TC_UP_SHIFT));
387}
388
389void ixgbe_dcb_read_rtrup2tc(struct ixgbe_hw *hw, u8 *map)
390{
391	switch (hw->mac.type) {
392	case ixgbe_mac_82599EB:
393	case ixgbe_mac_X540:
394	case ixgbe_mac_X550:
395	case ixgbe_mac_X550EM_x:
396		ixgbe_dcb_read_rtrup2tc_82599(hw, map);
397		break;
398	default:
399		break;
400	}
401}
402