drivers/net/ixgbe/ixgbe_dcb.c

   1 /*******************************************************************************
   2
   3   Intel 10 Gigabit PCI Express Linux driver
   4   Copyright(c) 1999 - 2010 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_dcb_config - Struct containing DCB settings.
  38  * @dcb_config: Pointer to DCB config structure
  39  *
  40  * This function checks DCB rules for DCB settings.
  41  * The following rules are checked:
  42  * 1. The sum of bandwidth percentages of all Bandwidth Groups must total 100%.
  43  * 2. The sum of bandwidth percentages of all Traffic Classes within a Bandwidth
  44  *    Group must total 100.
  45  * 3. A Traffic Class should not be set to both Link Strict Priority
  46  *    and Group Strict Priority.
  47  * 4. Link strict Bandwidth Groups can only have link strict traffic classes
  48  *    with zero bandwidth.
  49  */
  50 s32 ixgbe_dcb_check_config(struct ixgbe_dcb_config *dcb_config)
  51 {
  52         struct tc_bw_alloc *p;
  53         s32 ret_val = 0;
  54         u8 i, j, bw = 0, bw_id;
  55         u8 bw_sum[2][MAX_BW_GROUP];
  56         bool link_strict[2][MAX_BW_GROUP];
  57
  58         memset(bw_sum, 0, sizeof(bw_sum));
  59         memset(link_strict, 0, sizeof(link_strict));
  60
  61         /* First Tx, then Rx */
  62         for (i = 0; i < 2; i++) {
  63                 /* Check each traffic class for rule violation */
  64                 for (j = 0; j < MAX_TRAFFIC_CLASS; j++) {
  65                         p = &dcb_config->tc_config[j].path[i];
  66
  67                         bw = p->bwg_percent;
  68                         bw_id = p->bwg_id;
  69
  70                         if (bw_id >= MAX_BW_GROUP) {
  71                                 ret_val = DCB_ERR_CONFIG;
  72                                 goto err_config;
  73                         }
  74                         if (p->prio_type == prio_link) {
  75                                 link_strict[i][bw_id] = true;
  76                                 /* Link strict should have zero bandwidth */
  77                                 if (bw) {
  78                                         ret_val = DCB_ERR_LS_BW_NONZERO;
  79                                         goto err_config;
  80                                 }
  81                         } else if (!bw) {
  82                                 /*
  83                                  * Traffic classes without link strict
  84                                  * should have non-zero bandwidth.
  85                                  */
  86                                 ret_val = DCB_ERR_TC_BW_ZERO;
  87                                 goto err_config;
  88                         }
  89                         bw_sum[i][bw_id] += bw;
  90                 }
  91
  92                 bw = 0;
  93
  94                 /* Check each bandwidth group for rule violation */
  95                 for (j = 0; j < MAX_BW_GROUP; j++) {
  96                         bw += dcb_config->bw_percentage[i][j];
  97                         /*
  98                          * Sum of bandwidth percentages of all traffic classes
  99                          * within a Bandwidth Group must total 100 except for
 100                          * link strict group (zero bandwidth).
 101                          */
 102                         if (link_strict[i][j]) {
 103                                 if (bw_sum[i][j]) {
 104                                         /*
 105                                          * Link strict group should have zero
 106                                          * bandwidth.
 107                                          */
 108                                         ret_val = DCB_ERR_LS_BWG_NONZERO;
 109                                         goto err_config;
 110                                 }
 111                         } else if (bw_sum[i][j] != BW_PERCENT &&
 112                                    bw_sum[i][j] != 0) {
 113                                 ret_val = DCB_ERR_TC_BW;
 114                                 goto err_config;
 115                         }
 116                 }
 117
 118                 if (bw != BW_PERCENT) {
 119                         ret_val = DCB_ERR_BW_GROUP;
 120                         goto err_config;
 121                 }
 122         }
 123
 124 err_config:
 125         return ret_val;
 126 }
 127
 128 /**
 129  * ixgbe_dcb_calculate_tc_credits - Calculates traffic class credits
 130  * @ixgbe_dcb_config: Struct containing DCB settings.
 131  * @direction: Configuring either Tx or Rx.
 132  *
 133  * This function calculates the credits allocated to each traffic class.
 134  * It should be called only after the rules are checked by
 135  * ixgbe_dcb_check_config().
 136  */
 137 s32 ixgbe_dcb_calculate_tc_credits(struct ixgbe_dcb_config *dcb_config,
 138                                    u8 direction)
 139 {
 140         struct tc_bw_alloc *p;
 141         s32 ret_val = 0;
 142         /* Initialization values default for Tx settings */
 143         u32 credit_refill       = 0;
 144         u32 credit_max          = 0;
 145         u16 link_percentage     = 0;
 146         u8  bw_percent          = 0;
 147         u8  i;
 148
 149         if (dcb_config == NULL) {
 150                 ret_val = DCB_ERR_CONFIG;
 151                 goto out;
 152         }
 153
 154         /* Find out the link percentage for each TC first */
 155         for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
 156                 p = &dcb_config->tc_config[i].path[direction];
 157                 bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
 158
 159                 link_percentage = p->bwg_percent;
 160                 /* Must be careful of integer division for very small nums */
 161                 link_percentage = (link_percentage * bw_percent) / 100;
 162                 if (p->bwg_percent > 0 && link_percentage == 0)
 163                         link_percentage = 1;
 164
 165                 /* Save link_percentage for reference */
 166                 p->link_percent = (u8)link_percentage;
 167
 168                 /* Calculate credit refill and save it */
 169                 credit_refill = link_percentage * MINIMUM_CREDIT_REFILL;
 170                 p->data_credits_refill = (u16)credit_refill;
 171
 172                 /* Calculate maximum credit for the TC */
 173                 credit_max = (link_percentage * MAX_CREDIT) / 100;
 174
 175                 /*
 176                  * Adjustment based on rule checking, if the percentage
 177                  * of a TC is too small, the maximum credit may not be
 178                  * enough to send out a jumbo frame in data plane arbitration.
 179                  */
 180                 if (credit_max && (credit_max < MINIMUM_CREDIT_FOR_JUMBO))
 181                         credit_max = MINIMUM_CREDIT_FOR_JUMBO;
 182
 183                 if (direction == DCB_TX_CONFIG) {
 184                         /*
 185                          * Adjustment based on rule checking, if the
 186                          * percentage of a TC is too small, the maximum
 187                          * credit may not be enough to send out a TSO
 188                          * packet in descriptor plane arbitration.
 189                          */
 190                         if (credit_max &&
 191                             (credit_max < MINIMUM_CREDIT_FOR_TSO))
 192                                 credit_max = MINIMUM_CREDIT_FOR_TSO;
 193
 194                         dcb_config->tc_config[i].desc_credits_max =
 195                                 (u16)credit_max;
 196                 }
 197
 198                 p->data_credits_max = (u16)credit_max;
 199         }
 200
 201 out:
 202         return ret_val;
 203 }
 204
 205 /**
 206  * ixgbe_dcb_get_tc_stats - Returns status of each traffic class
 207  * @hw: pointer to hardware structure
 208  * @stats: pointer to statistics structure
 209  * @tc_count:  Number of elements in bwg_array.
 210  *
 211  * This function returns the status data for each of the Traffic Classes in use.
 212  */
 213 s32 ixgbe_dcb_get_tc_stats(struct ixgbe_hw *hw, struct ixgbe_hw_stats *stats,
 214                            u8 tc_count)
 215 {
 216         s32 ret = 0;
 217         if (hw->mac.type == ixgbe_mac_82598EB)
 218                 ret = ixgbe_dcb_get_tc_stats_82598(hw, stats, tc_count);
 219         else if (hw->mac.type == ixgbe_mac_82599EB)
 220                 ret = ixgbe_dcb_get_tc_stats_82599(hw, stats, tc_count);
 221         return ret;
 222 }
 223
 224 /**
 225  * ixgbe_dcb_get_pfc_stats - Returns CBFC status of each traffic class
 226  * hw - pointer to hardware structure
 227  * stats - pointer to statistics structure
 228  * tc_count -  Number of elements in bwg_array.
 229  *
 230  * This function returns the CBFC status data for each of the Traffic Classes.
 231  */
 232 s32 ixgbe_dcb_get_pfc_stats(struct ixgbe_hw *hw, struct ixgbe_hw_stats *stats,
 233                             u8 tc_count)
 234 {
 235         s32 ret = 0;
 236         if (hw->mac.type == ixgbe_mac_82598EB)
 237                 ret = ixgbe_dcb_get_pfc_stats_82598(hw, stats, tc_count);
 238         else if (hw->mac.type == ixgbe_mac_82599EB)
 239                 ret = ixgbe_dcb_get_pfc_stats_82599(hw, stats, tc_count);
 240         return ret;
 241 }
 242
 243 /**
 244  * ixgbe_dcb_config_rx_arbiter - Config Rx arbiter
 245  * @hw: pointer to hardware structure
 246  * @dcb_config: pointer to ixgbe_dcb_config structure
 247  *
 248  * Configure Rx Data Arbiter and credits for each traffic class.
 249  */
 250 s32 ixgbe_dcb_config_rx_arbiter(struct ixgbe_hw *hw,
 251                                 struct ixgbe_dcb_config *dcb_config)
 252 {
 253         s32 ret = 0;
 254         if (hw->mac.type == ixgbe_mac_82598EB)
 255                 ret = ixgbe_dcb_config_rx_arbiter_82598(hw, dcb_config);
 256         else if (hw->mac.type == ixgbe_mac_82599EB)
 257                 ret = ixgbe_dcb_config_rx_arbiter_82599(hw, dcb_config);
 258         return ret;
 259 }
 260
 261 /**
 262  * ixgbe_dcb_config_tx_desc_arbiter - Config Tx Desc arbiter
 263  * @hw: pointer to hardware structure
 264  * @dcb_config: pointer to ixgbe_dcb_config structure
 265  *
 266  * Configure Tx Descriptor Arbiter and credits for each traffic class.
 267  */
 268 s32 ixgbe_dcb_config_tx_desc_arbiter(struct ixgbe_hw *hw,
 269                                      struct ixgbe_dcb_config *dcb_config)
 270 {
 271         s32 ret = 0;
 272         if (hw->mac.type == ixgbe_mac_82598EB)
 273                 ret = ixgbe_dcb_config_tx_desc_arbiter_82598(hw, dcb_config);
 274         else if (hw->mac.type == ixgbe_mac_82599EB)
 275                 ret = ixgbe_dcb_config_tx_desc_arbiter_82599(hw, dcb_config);
 276         return ret;
 277 }
 278
 279 /**
 280  * ixgbe_dcb_config_tx_data_arbiter - Config Tx data arbiter
 281  * @hw: pointer to hardware structure
 282  * @dcb_config: pointer to ixgbe_dcb_config structure
 283  *
 284  * Configure Tx Data Arbiter and credits for each traffic class.
 285  */
 286 s32 ixgbe_dcb_config_tx_data_arbiter(struct ixgbe_hw *hw,
 287                                      struct ixgbe_dcb_config *dcb_config)
 288 {
 289         s32 ret = 0;
 290         if (hw->mac.type == ixgbe_mac_82598EB)
 291                 ret = ixgbe_dcb_config_tx_data_arbiter_82598(hw, dcb_config);
 292         else if (hw->mac.type == ixgbe_mac_82599EB)
 293                 ret = ixgbe_dcb_config_tx_data_arbiter_82599(hw, dcb_config);
 294         return ret;
 295 }
 296
 297 /**
 298  * ixgbe_dcb_config_pfc - Config priority flow control
 299  * @hw: pointer to hardware structure
 300  * @dcb_config: pointer to ixgbe_dcb_config structure
 301  *
 302  * Configure Priority Flow Control for each traffic class.
 303  */
 304 s32 ixgbe_dcb_config_pfc(struct ixgbe_hw *hw,
 305                          struct ixgbe_dcb_config *dcb_config)
 306 {
 307         s32 ret = 0;
 308         if (hw->mac.type == ixgbe_mac_82598EB)
 309                 ret = ixgbe_dcb_config_pfc_82598(hw, dcb_config);
 310         else if (hw->mac.type == ixgbe_mac_82599EB)
 311                 ret = ixgbe_dcb_config_pfc_82599(hw, dcb_config);
 312         return ret;
 313 }
 314
 315 /**
 316  * ixgbe_dcb_config_tc_stats - Config traffic class statistics
 317  * @hw: pointer to hardware structure
 318  *
 319  * Configure queue statistics registers, all queues belonging to same traffic
 320  * class uses a single set of queue statistics counters.
 321  */
 322 s32 ixgbe_dcb_config_tc_stats(struct ixgbe_hw *hw)
 323 {
 324         s32 ret = 0;
 325         if (hw->mac.type == ixgbe_mac_82598EB)
 326                 ret = ixgbe_dcb_config_tc_stats_82598(hw);
 327         else if (hw->mac.type == ixgbe_mac_82599EB)
 328                 ret = ixgbe_dcb_config_tc_stats_82599(hw);
 329         return ret;
 330 }
 331
 332 /**
 333  * ixgbe_dcb_hw_config - Config and enable DCB
 334  * @hw: pointer to hardware structure
 335  * @dcb_config: pointer to ixgbe_dcb_config structure
 336  *
 337  * Configure dcb settings and enable dcb mode.
 338  */
 339 s32 ixgbe_dcb_hw_config(struct ixgbe_hw *hw,
 340                         struct ixgbe_dcb_config *dcb_config)
 341 {
 342         s32 ret = 0;
 343         if (hw->mac.type == ixgbe_mac_82598EB)
 344                 ret = ixgbe_dcb_hw_config_82598(hw, dcb_config);
 345         else if (hw->mac.type == ixgbe_mac_82599EB)
 346                 ret = ixgbe_dcb_hw_config_82599(hw, dcb_config);
 347         return ret;
 348 }
 349