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

   1 /*******************************************************************************
   2
   3   Intel(R) Gigabit Ethernet Linux driver
   4   Copyright(c) 2007-2013 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   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  24   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  25
  26 *******************************************************************************/
  27
  28 #include "e1000_mbx.h"
  29
  30 /**
  31  *  igb_read_mbx - Reads a message from the mailbox
  32  *  @hw: pointer to the HW structure
  33  *  @msg: The message buffer
  34  *  @size: Length of buffer
  35  *  @mbx_id: id of mailbox to read
  36  *
  37  *  returns SUCCESS if it successfully read message from buffer
  38  **/
  39 s32 igb_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
  40 {
  41         struct e1000_mbx_info *mbx = &hw->mbx;
  42         s32 ret_val = -E1000_ERR_MBX;
  43
  44         /* limit read to size of mailbox */
  45         if (size > mbx->size)
  46                 size = mbx->size;
  47
  48         if (mbx->ops.read)
  49                 ret_val = mbx->ops.read(hw, msg, size, mbx_id);
  50
  51         return ret_val;
  52 }
  53
  54 /**
  55  *  igb_write_mbx - Write a message to the mailbox
  56  *  @hw: pointer to the HW structure
  57  *  @msg: The message buffer
  58  *  @size: Length of buffer
  59  *  @mbx_id: id of mailbox to write
  60  *
  61  *  returns SUCCESS if it successfully copied message into the buffer
  62  **/
  63 s32 igb_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
  64 {
  65         struct e1000_mbx_info *mbx = &hw->mbx;
  66         s32 ret_val = 0;
  67
  68         if (size > mbx->size)
  69                 ret_val = -E1000_ERR_MBX;
  70
  71         else if (mbx->ops.write)
  72                 ret_val = mbx->ops.write(hw, msg, size, mbx_id);
  73
  74         return ret_val;
  75 }
  76
  77 /**
  78  *  igb_check_for_msg - checks to see if someone sent us mail
  79  *  @hw: pointer to the HW structure
  80  *  @mbx_id: id of mailbox to check
  81  *
  82  *  returns SUCCESS if the Status bit was found or else ERR_MBX
  83  **/
  84 s32 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
  85 {
  86         struct e1000_mbx_info *mbx = &hw->mbx;
  87         s32 ret_val = -E1000_ERR_MBX;
  88
  89         if (mbx->ops.check_for_msg)
  90                 ret_val = mbx->ops.check_for_msg(hw, mbx_id);
  91
  92         return ret_val;
  93 }
  94
  95 /**
  96  *  igb_check_for_ack - checks to see if someone sent us ACK
  97  *  @hw: pointer to the HW structure
  98  *  @mbx_id: id of mailbox to check
  99  *
 100  *  returns SUCCESS if the Status bit was found or else ERR_MBX
 101  **/
 102 s32 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
 103 {
 104         struct e1000_mbx_info *mbx = &hw->mbx;
 105         s32 ret_val = -E1000_ERR_MBX;
 106
 107         if (mbx->ops.check_for_ack)
 108                 ret_val = mbx->ops.check_for_ack(hw, mbx_id);
 109
 110         return ret_val;
 111 }
 112
 113 /**
 114  *  igb_check_for_rst - checks to see if other side has reset
 115  *  @hw: pointer to the HW structure
 116  *  @mbx_id: id of mailbox to check
 117  *
 118  *  returns SUCCESS if the Status bit was found or else ERR_MBX
 119  **/
 120 s32 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
 121 {
 122         struct e1000_mbx_info *mbx = &hw->mbx;
 123         s32 ret_val = -E1000_ERR_MBX;
 124
 125         if (mbx->ops.check_for_rst)
 126                 ret_val = mbx->ops.check_for_rst(hw, mbx_id);
 127
 128         return ret_val;
 129 }
 130
 131 /**
 132  *  igb_poll_for_msg - Wait for message notification
 133  *  @hw: pointer to the HW structure
 134  *  @mbx_id: id of mailbox to write
 135  *
 136  *  returns SUCCESS if it successfully received a message notification
 137  **/
 138 static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
 139 {
 140         struct e1000_mbx_info *mbx = &hw->mbx;
 141         int countdown = mbx->timeout;
 142
 143         if (!countdown || !mbx->ops.check_for_msg)
 144                 goto out;
 145
 146         while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
 147                 countdown--;
 148                 if (!countdown)
 149                         break;
 150                 udelay(mbx->usec_delay);
 151         }
 152
 153         /* if we failed, all future posted messages fail until reset */
 154         if (!countdown)
 155                 mbx->timeout = 0;
 156 out:
 157         return countdown ? 0 : -E1000_ERR_MBX;
 158 }
 159
 160 /**
 161  *  igb_poll_for_ack - Wait for message acknowledgement
 162  *  @hw: pointer to the HW structure
 163  *  @mbx_id: id of mailbox to write
 164  *
 165  *  returns SUCCESS if it successfully received a message acknowledgement
 166  **/
 167 static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
 168 {
 169         struct e1000_mbx_info *mbx = &hw->mbx;
 170         int countdown = mbx->timeout;
 171
 172         if (!countdown || !mbx->ops.check_for_ack)
 173                 goto out;
 174
 175         while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
 176                 countdown--;
 177                 if (!countdown)
 178                         break;
 179                 udelay(mbx->usec_delay);
 180         }
 181
 182         /* if we failed, all future posted messages fail until reset */
 183         if (!countdown)
 184                 mbx->timeout = 0;
 185 out:
 186         return countdown ? 0 : -E1000_ERR_MBX;
 187 }
 188
 189 /**
 190  *  igb_read_posted_mbx - Wait for message notification and receive message
 191  *  @hw: pointer to the HW structure
 192  *  @msg: The message buffer
 193  *  @size: Length of buffer
 194  *  @mbx_id: id of mailbox to write
 195  *
 196  *  returns SUCCESS if it successfully received a message notification and
 197  *  copied it into the receive buffer.
 198  **/
 199 static s32 igb_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
 200                                u16 mbx_id)
 201 {
 202         struct e1000_mbx_info *mbx = &hw->mbx;
 203         s32 ret_val = -E1000_ERR_MBX;
 204
 205         if (!mbx->ops.read)
 206                 goto out;
 207
 208         ret_val = igb_poll_for_msg(hw, mbx_id);
 209
 210         if (!ret_val)
 211                 ret_val = mbx->ops.read(hw, msg, size, mbx_id);
 212 out:
 213         return ret_val;
 214 }
 215
 216 /**
 217  *  igb_write_posted_mbx - Write a message to the mailbox, wait for ack
 218  *  @hw: pointer to the HW structure
 219  *  @msg: The message buffer
 220  *  @size: Length of buffer
 221  *  @mbx_id: id of mailbox to write
 222  *
 223  *  returns SUCCESS if it successfully copied message into the buffer and
 224  *  received an ack to that message within delay * timeout period
 225  **/
 226 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
 227                                 u16 mbx_id)
 228 {
 229         struct e1000_mbx_info *mbx = &hw->mbx;
 230         s32 ret_val = -E1000_ERR_MBX;
 231
 232         /* exit if either we can't write or there isn't a defined timeout */
 233         if (!mbx->ops.write || !mbx->timeout)
 234                 goto out;
 235
 236         /* send msg */
 237         ret_val = mbx->ops.write(hw, msg, size, mbx_id);
 238
 239         /* if msg sent wait until we receive an ack */
 240         if (!ret_val)
 241                 ret_val = igb_poll_for_ack(hw, mbx_id);
 242 out:
 243         return ret_val;
 244 }
 245
 246 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
 247 {
 248         u32 mbvficr = rd32(E1000_MBVFICR);
 249         s32 ret_val = -E1000_ERR_MBX;
 250
 251         if (mbvficr & mask) {
 252                 ret_val = 0;
 253                 wr32(E1000_MBVFICR, mask);
 254         }
 255
 256         return ret_val;
 257 }
 258
 259 /**
 260  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
 261  *  @hw: pointer to the HW structure
 262  *  @vf_number: the VF index
 263  *
 264  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 265  **/
 266 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
 267 {
 268         s32 ret_val = -E1000_ERR_MBX;
 269
 270         if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
 271                 ret_val = 0;
 272                 hw->mbx.stats.reqs++;
 273         }
 274
 275         return ret_val;
 276 }
 277
 278 /**
 279  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
 280  *  @hw: pointer to the HW structure
 281  *  @vf_number: the VF index
 282  *
 283  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 284  **/
 285 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
 286 {
 287         s32 ret_val = -E1000_ERR_MBX;
 288
 289         if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
 290                 ret_val = 0;
 291                 hw->mbx.stats.acks++;
 292         }
 293
 294         return ret_val;
 295 }
 296
 297 /**
 298  *  igb_check_for_rst_pf - checks to see if the VF has reset
 299  *  @hw: pointer to the HW structure
 300  *  @vf_number: the VF index
 301  *
 302  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 303  **/
 304 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
 305 {
 306         u32 vflre = rd32(E1000_VFLRE);
 307         s32 ret_val = -E1000_ERR_MBX;
 308
 309         if (vflre & (1 << vf_number)) {
 310                 ret_val = 0;
 311                 wr32(E1000_VFLRE, (1 << vf_number));
 312                 hw->mbx.stats.rsts++;
 313         }
 314
 315         return ret_val;
 316 }
 317
 318 /**
 319  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
 320  *  @hw: pointer to the HW structure
 321  *  @vf_number: the VF index
 322  *
 323  *  return SUCCESS if we obtained the mailbox lock
 324  **/
 325 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
 326 {
 327         s32 ret_val = -E1000_ERR_MBX;
 328         u32 p2v_mailbox;
 329
 330         /* Take ownership of the buffer */
 331         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
 332
 333         /* reserve mailbox for vf use */
 334         p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
 335         if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
 336                 ret_val = 0;
 337
 338         return ret_val;
 339 }
 340
 341 /**
 342  *  igb_write_mbx_pf - Places a message in the mailbox
 343  *  @hw: pointer to the HW structure
 344  *  @msg: The message buffer
 345  *  @size: Length of buffer
 346  *  @vf_number: the VF index
 347  *
 348  *  returns SUCCESS if it successfully copied message into the buffer
 349  **/
 350 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 351                             u16 vf_number)
 352 {
 353         s32 ret_val;
 354         u16 i;
 355
 356         /* lock the mailbox to prevent pf/vf race condition */
 357         ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
 358         if (ret_val)
 359                 goto out_no_write;
 360
 361         /* flush msg and acks as we are overwriting the message buffer */
 362         igb_check_for_msg_pf(hw, vf_number);
 363         igb_check_for_ack_pf(hw, vf_number);
 364
 365         /* copy the caller specified message to the mailbox memory buffer */
 366         for (i = 0; i < size; i++)
 367                 array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);
 368
 369         /* Interrupt VF to tell it a message has been sent and release buffer*/
 370         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
 371
 372         /* update stats */
 373         hw->mbx.stats.msgs_tx++;
 374
 375 out_no_write:
 376         return ret_val;
 377
 378 }
 379
 380 /**
 381  *  igb_read_mbx_pf - Read a message from the mailbox
 382  *  @hw: pointer to the HW structure
 383  *  @msg: The message buffer
 384  *  @size: Length of buffer
 385  *  @vf_number: the VF index
 386  *
 387  *  This function copies a message from the mailbox buffer to the caller's
 388  *  memory buffer.  The presumption is that the caller knows that there was
 389  *  a message due to a VF request so no polling for message is needed.
 390  **/
 391 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 392                            u16 vf_number)
 393 {
 394         s32 ret_val;
 395         u16 i;
 396
 397         /* lock the mailbox to prevent pf/vf race condition */
 398         ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
 399         if (ret_val)
 400                 goto out_no_read;
 401
 402         /* copy the message to the mailbox memory buffer */
 403         for (i = 0; i < size; i++)
 404                 msg[i] = array_rd32(E1000_VMBMEM(vf_number), i);
 405
 406         /* Acknowledge the message and release buffer */
 407         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
 408
 409         /* update stats */
 410         hw->mbx.stats.msgs_rx++;
 411
 412 out_no_read:
 413         return ret_val;
 414 }
 415
 416 /**
 417  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
 418  *  @hw: pointer to the HW structure
 419  *
 420  *  Initializes the hw->mbx struct to correct values for pf mailbox
 421  */
 422 s32 igb_init_mbx_params_pf(struct e1000_hw *hw)
 423 {
 424         struct e1000_mbx_info *mbx = &hw->mbx;
 425
 426         mbx->timeout = 0;
 427         mbx->usec_delay = 0;
 428
 429         mbx->size = E1000_VFMAILBOX_SIZE;
 430
 431         mbx->ops.read = igb_read_mbx_pf;
 432         mbx->ops.write = igb_write_mbx_pf;
 433         mbx->ops.read_posted = igb_read_posted_mbx;
 434         mbx->ops.write_posted = igb_write_posted_mbx;
 435         mbx->ops.check_for_msg = igb_check_for_msg_pf;
 436         mbx->ops.check_for_ack = igb_check_for_ack_pf;
 437         mbx->ops.check_for_rst = igb_check_for_rst_pf;
 438
 439         mbx->stats.msgs_tx = 0;
 440         mbx->stats.msgs_rx = 0;
 441         mbx->stats.reqs = 0;
 442         mbx->stats.acks = 0;
 443         mbx->stats.rsts = 0;
 444
 445         return 0;
 446 }
 447