drivers/net/ethernet/intel/igb/e1000_mbx.c

   1 /* Intel(R) Gigabit Ethernet Linux driver
   2  * Copyright(c) 2007-2014 Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, see <http://www.gnu.org/licenses/>.
  15  *
  16  * The full GNU General Public License is included in this distribution in
  17  * the file called "COPYING".
  18  *
  19  * Contact Information:
  20  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  21  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  22  */
  23
  24 #include "e1000_mbx.h"
  25
  26 /**
  27  *  igb_read_mbx - Reads a message from the mailbox
  28  *  @hw: pointer to the HW structure
  29  *  @msg: The message buffer
  30  *  @size: Length of buffer
  31  *  @mbx_id: id of mailbox to read
  32  *
  33  *  returns SUCCESS if it successfully read message from buffer
  34  **/
  35 s32 igb_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
  36 {
  37         struct e1000_mbx_info *mbx = &hw->mbx;
  38         s32 ret_val = -E1000_ERR_MBX;
  39
  40         /* limit read to size of mailbox */
  41         if (size > mbx->size)
  42                 size = mbx->size;
  43
  44         if (mbx->ops.read)
  45                 ret_val = mbx->ops.read(hw, msg, size, mbx_id);
  46
  47         return ret_val;
  48 }
  49
  50 /**
  51  *  igb_write_mbx - Write a message to the mailbox
  52  *  @hw: pointer to the HW structure
  53  *  @msg: The message buffer
  54  *  @size: Length of buffer
  55  *  @mbx_id: id of mailbox to write
  56  *
  57  *  returns SUCCESS if it successfully copied message into the buffer
  58  **/
  59 s32 igb_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
  60 {
  61         struct e1000_mbx_info *mbx = &hw->mbx;
  62         s32 ret_val = 0;
  63
  64         if (size > mbx->size)
  65                 ret_val = -E1000_ERR_MBX;
  66
  67         else if (mbx->ops.write)
  68                 ret_val = mbx->ops.write(hw, msg, size, mbx_id);
  69
  70         return ret_val;
  71 }
  72
  73 /**
  74  *  igb_check_for_msg - checks to see if someone sent us mail
  75  *  @hw: pointer to the HW structure
  76  *  @mbx_id: id of mailbox to check
  77  *
  78  *  returns SUCCESS if the Status bit was found or else ERR_MBX
  79  **/
  80 s32 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
  81 {
  82         struct e1000_mbx_info *mbx = &hw->mbx;
  83         s32 ret_val = -E1000_ERR_MBX;
  84
  85         if (mbx->ops.check_for_msg)
  86                 ret_val = mbx->ops.check_for_msg(hw, mbx_id);
  87
  88         return ret_val;
  89 }
  90
  91 /**
  92  *  igb_check_for_ack - checks to see if someone sent us ACK
  93  *  @hw: pointer to the HW structure
  94  *  @mbx_id: id of mailbox to check
  95  *
  96  *  returns SUCCESS if the Status bit was found or else ERR_MBX
  97  **/
  98 s32 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
  99 {
 100         struct e1000_mbx_info *mbx = &hw->mbx;
 101         s32 ret_val = -E1000_ERR_MBX;
 102
 103         if (mbx->ops.check_for_ack)
 104                 ret_val = mbx->ops.check_for_ack(hw, mbx_id);
 105
 106         return ret_val;
 107 }
 108
 109 /**
 110  *  igb_check_for_rst - checks to see if other side has reset
 111  *  @hw: pointer to the HW structure
 112  *  @mbx_id: id of mailbox to check
 113  *
 114  *  returns SUCCESS if the Status bit was found or else ERR_MBX
 115  **/
 116 s32 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
 117 {
 118         struct e1000_mbx_info *mbx = &hw->mbx;
 119         s32 ret_val = -E1000_ERR_MBX;
 120
 121         if (mbx->ops.check_for_rst)
 122                 ret_val = mbx->ops.check_for_rst(hw, mbx_id);
 123
 124         return ret_val;
 125 }
 126
 127 /**
 128  *  igb_poll_for_msg - Wait for message notification
 129  *  @hw: pointer to the HW structure
 130  *  @mbx_id: id of mailbox to write
 131  *
 132  *  returns SUCCESS if it successfully received a message notification
 133  **/
 134 static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
 135 {
 136         struct e1000_mbx_info *mbx = &hw->mbx;
 137         int countdown = mbx->timeout;
 138
 139         if (!countdown || !mbx->ops.check_for_msg)
 140                 goto out;
 141
 142         while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
 143                 countdown--;
 144                 if (!countdown)
 145                         break;
 146                 udelay(mbx->usec_delay);
 147         }
 148
 149         /* if we failed, all future posted messages fail until reset */
 150         if (!countdown)
 151                 mbx->timeout = 0;
 152 out:
 153         return countdown ? 0 : -E1000_ERR_MBX;
 154 }
 155
 156 /**
 157  *  igb_poll_for_ack - Wait for message acknowledgement
 158  *  @hw: pointer to the HW structure
 159  *  @mbx_id: id of mailbox to write
 160  *
 161  *  returns SUCCESS if it successfully received a message acknowledgement
 162  **/
 163 static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
 164 {
 165         struct e1000_mbx_info *mbx = &hw->mbx;
 166         int countdown = mbx->timeout;
 167
 168         if (!countdown || !mbx->ops.check_for_ack)
 169                 goto out;
 170
 171         while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
 172                 countdown--;
 173                 if (!countdown)
 174                         break;
 175                 udelay(mbx->usec_delay);
 176         }
 177
 178         /* if we failed, all future posted messages fail until reset */
 179         if (!countdown)
 180                 mbx->timeout = 0;
 181 out:
 182         return countdown ? 0 : -E1000_ERR_MBX;
 183 }
 184
 185 /**
 186  *  igb_read_posted_mbx - Wait for message notification and receive message
 187  *  @hw: pointer to the HW structure
 188  *  @msg: The message buffer
 189  *  @size: Length of buffer
 190  *  @mbx_id: id of mailbox to write
 191  *
 192  *  returns SUCCESS if it successfully received a message notification and
 193  *  copied it into the receive buffer.
 194  **/
 195 static s32 igb_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
 196                                u16 mbx_id)
 197 {
 198         struct e1000_mbx_info *mbx = &hw->mbx;
 199         s32 ret_val = -E1000_ERR_MBX;
 200
 201         if (!mbx->ops.read)
 202                 goto out;
 203
 204         ret_val = igb_poll_for_msg(hw, mbx_id);
 205
 206         if (!ret_val)
 207                 ret_val = mbx->ops.read(hw, msg, size, mbx_id);
 208 out:
 209         return ret_val;
 210 }
 211
 212 /**
 213  *  igb_write_posted_mbx - Write a message to the mailbox, wait for ack
 214  *  @hw: pointer to the HW structure
 215  *  @msg: The message buffer
 216  *  @size: Length of buffer
 217  *  @mbx_id: id of mailbox to write
 218  *
 219  *  returns SUCCESS if it successfully copied message into the buffer and
 220  *  received an ack to that message within delay * timeout period
 221  **/
 222 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
 223                                 u16 mbx_id)
 224 {
 225         struct e1000_mbx_info *mbx = &hw->mbx;
 226         s32 ret_val = -E1000_ERR_MBX;
 227
 228         /* exit if either we can't write or there isn't a defined timeout */
 229         if (!mbx->ops.write || !mbx->timeout)
 230                 goto out;
 231
 232         /* send msg */
 233         ret_val = mbx->ops.write(hw, msg, size, mbx_id);
 234
 235         /* if msg sent wait until we receive an ack */
 236         if (!ret_val)
 237                 ret_val = igb_poll_for_ack(hw, mbx_id);
 238 out:
 239         return ret_val;
 240 }
 241
 242 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
 243 {
 244         u32 mbvficr = rd32(E1000_MBVFICR);
 245         s32 ret_val = -E1000_ERR_MBX;
 246
 247         if (mbvficr & mask) {
 248                 ret_val = 0;
 249                 wr32(E1000_MBVFICR, mask);
 250         }
 251
 252         return ret_val;
 253 }
 254
 255 /**
 256  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
 257  *  @hw: pointer to the HW structure
 258  *  @vf_number: the VF index
 259  *
 260  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 261  **/
 262 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
 263 {
 264         s32 ret_val = -E1000_ERR_MBX;
 265
 266         if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
 267                 ret_val = 0;
 268                 hw->mbx.stats.reqs++;
 269         }
 270
 271         return ret_val;
 272 }
 273
 274 /**
 275  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
 276  *  @hw: pointer to the HW structure
 277  *  @vf_number: the VF index
 278  *
 279  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 280  **/
 281 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
 282 {
 283         s32 ret_val = -E1000_ERR_MBX;
 284
 285         if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
 286                 ret_val = 0;
 287                 hw->mbx.stats.acks++;
 288         }
 289
 290         return ret_val;
 291 }
 292
 293 /**
 294  *  igb_check_for_rst_pf - checks to see if the VF has reset
 295  *  @hw: pointer to the HW structure
 296  *  @vf_number: the VF index
 297  *
 298  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 299  **/
 300 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
 301 {
 302         u32 vflre = rd32(E1000_VFLRE);
 303         s32 ret_val = -E1000_ERR_MBX;
 304
 305         if (vflre & BIT(vf_number)) {
 306                 ret_val = 0;
 307                 wr32(E1000_VFLRE, BIT(vf_number));
 308                 hw->mbx.stats.rsts++;
 309         }
 310
 311         return ret_val;
 312 }
 313
 314 /**
 315  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
 316  *  @hw: pointer to the HW structure
 317  *  @vf_number: the VF index
 318  *
 319  *  return SUCCESS if we obtained the mailbox lock
 320  **/
 321 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
 322 {
 323         s32 ret_val = -E1000_ERR_MBX;
 324         u32 p2v_mailbox;
 325         int count = 10;
 326
 327         do {
 328                 /* Take ownership of the buffer */
 329                 wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
 330
 331                 /* reserve mailbox for vf use */
 332                 p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
 333                 if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
 334                         ret_val = 0;
 335                         break;
 336                 }
 337                 udelay(1000);
 338         } while (count-- > 0);
 339
 340         return ret_val;
 341 }
 342
 343 /**
 344  *  igb_write_mbx_pf - Places a message in the mailbox
 345  *  @hw: pointer to the HW structure
 346  *  @msg: The message buffer
 347  *  @size: Length of buffer
 348  *  @vf_number: the VF index
 349  *
 350  *  returns SUCCESS if it successfully copied message into the buffer
 351  **/
 352 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 353                             u16 vf_number)
 354 {
 355         s32 ret_val;
 356         u16 i;
 357
 358         /* lock the mailbox to prevent pf/vf race condition */
 359         ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
 360         if (ret_val)
 361                 goto out_no_write;
 362
 363         /* flush msg and acks as we are overwriting the message buffer */
 364         igb_check_for_msg_pf(hw, vf_number);
 365         igb_check_for_ack_pf(hw, vf_number);
 366
 367         /* copy the caller specified message to the mailbox memory buffer */
 368         for (i = 0; i < size; i++)
 369                 array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);
 370
 371         /* Interrupt VF to tell it a message has been sent and release buffer*/
 372         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
 373
 374         /* update stats */
 375         hw->mbx.stats.msgs_tx++;
 376
 377 out_no_write:
 378         return ret_val;
 379
 380 }
 381
 382 /**
 383  *  igb_read_mbx_pf - Read a message from the mailbox
 384  *  @hw: pointer to the HW structure
 385  *  @msg: The message buffer
 386  *  @size: Length of buffer
 387  *  @vf_number: the VF index
 388  *
 389  *  This function copies a message from the mailbox buffer to the caller's
 390  *  memory buffer.  The presumption is that the caller knows that there was
 391  *  a message due to a VF request so no polling for message is needed.
 392  **/
 393 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 394                            u16 vf_number)
 395 {
 396         s32 ret_val;
 397         u16 i;
 398
 399         /* lock the mailbox to prevent pf/vf race condition */
 400         ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
 401         if (ret_val)
 402                 goto out_no_read;
 403
 404         /* copy the message to the mailbox memory buffer */
 405         for (i = 0; i < size; i++)
 406                 msg[i] = array_rd32(E1000_VMBMEM(vf_number), i);
 407
 408         /* Acknowledge the message and release buffer */
 409         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
 410
 411         /* update stats */
 412         hw->mbx.stats.msgs_rx++;
 413
 414 out_no_read:
 415         return ret_val;
 416 }
 417
 418 /**
 419  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
 420  *  @hw: pointer to the HW structure
 421  *
 422  *  Initializes the hw->mbx struct to correct values for pf mailbox
 423  */
 424 s32 igb_init_mbx_params_pf(struct e1000_hw *hw)
 425 {
 426         struct e1000_mbx_info *mbx = &hw->mbx;
 427
 428         mbx->timeout = 0;
 429         mbx->usec_delay = 0;
 430
 431         mbx->size = E1000_VFMAILBOX_SIZE;
 432
 433         mbx->ops.read = igb_read_mbx_pf;
 434         mbx->ops.write = igb_write_mbx_pf;
 435         mbx->ops.read_posted = igb_read_posted_mbx;
 436         mbx->ops.write_posted = igb_write_posted_mbx;
 437         mbx->ops.check_for_msg = igb_check_for_msg_pf;
 438         mbx->ops.check_for_ack = igb_check_for_ack_pf;
 439         mbx->ops.check_for_rst = igb_check_for_rst_pf;
 440
 441         mbx->stats.msgs_tx = 0;
 442         mbx->stats.msgs_rx = 0;
 443         mbx->stats.reqs = 0;
 444         mbx->stats.acks = 0;
 445         mbx->stats.rsts = 0;
 446
 447         return 0;
 448 }
 449