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, u16 mbx_id)
 200 {
 201         struct e1000_mbx_info *mbx = &hw->mbx;
 202         s32 ret_val = -E1000_ERR_MBX;
 203
 204         if (!mbx->ops.read)
 205                 goto out;
 206
 207         ret_val = igb_poll_for_msg(hw, mbx_id);
 208
 209         if (!ret_val)
 210                 ret_val = mbx->ops.read(hw, msg, size, mbx_id);
 211 out:
 212         return ret_val;
 213 }
 214
 215 /**
 216  *  igb_write_posted_mbx - Write a message to the mailbox, wait for ack
 217  *  @hw: pointer to the HW structure
 218  *  @msg: The message buffer
 219  *  @size: Length of buffer
 220  *  @mbx_id: id of mailbox to write
 221  *
 222  *  returns SUCCESS if it successfully copied message into the buffer and
 223  *  received an ack to that message within delay * timeout period
 224  **/
 225 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
 226 {
 227         struct e1000_mbx_info *mbx = &hw->mbx;
 228         s32 ret_val = -E1000_ERR_MBX;
 229
 230         /* exit if either we can't write or there isn't a defined timeout */
 231         if (!mbx->ops.write || !mbx->timeout)
 232                 goto out;
 233
 234         /* send msg */
 235         ret_val = mbx->ops.write(hw, msg, size, mbx_id);
 236
 237         /* if msg sent wait until we receive an ack */
 238         if (!ret_val)
 239                 ret_val = igb_poll_for_ack(hw, mbx_id);
 240 out:
 241         return ret_val;
 242 }
 243
 244 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
 245 {
 246         u32 mbvficr = rd32(E1000_MBVFICR);
 247         s32 ret_val = -E1000_ERR_MBX;
 248
 249         if (mbvficr & mask) {
 250                 ret_val = 0;
 251                 wr32(E1000_MBVFICR, mask);
 252         }
 253
 254         return ret_val;
 255 }
 256
 257 /**
 258  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
 259  *  @hw: pointer to the HW structure
 260  *  @vf_number: the VF index
 261  *
 262  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 263  **/
 264 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
 265 {
 266         s32 ret_val = -E1000_ERR_MBX;
 267
 268         if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
 269                 ret_val = 0;
 270                 hw->mbx.stats.reqs++;
 271         }
 272
 273         return ret_val;
 274 }
 275
 276 /**
 277  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
 278  *  @hw: pointer to the HW structure
 279  *  @vf_number: the VF index
 280  *
 281  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 282  **/
 283 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
 284 {
 285         s32 ret_val = -E1000_ERR_MBX;
 286
 287         if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
 288                 ret_val = 0;
 289                 hw->mbx.stats.acks++;
 290         }
 291
 292         return ret_val;
 293 }
 294
 295 /**
 296  *  igb_check_for_rst_pf - checks to see if the VF has reset
 297  *  @hw: pointer to the HW structure
 298  *  @vf_number: the VF index
 299  *
 300  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 301  **/
 302 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
 303 {
 304         u32 vflre = rd32(E1000_VFLRE);
 305         s32 ret_val = -E1000_ERR_MBX;
 306
 307         if (vflre & (1 << vf_number)) {
 308                 ret_val = 0;
 309                 wr32(E1000_VFLRE, (1 << vf_number));
 310                 hw->mbx.stats.rsts++;
 311         }
 312
 313         return ret_val;
 314 }
 315
 316 /**
 317  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
 318  *  @hw: pointer to the HW structure
 319  *  @vf_number: the VF index
 320  *
 321  *  return SUCCESS if we obtained the mailbox lock
 322  **/
 323 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
 324 {
 325         s32 ret_val = -E1000_ERR_MBX;
 326         u32 p2v_mailbox;
 327
 328
 329         /* Take ownership of the buffer */
 330         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
 331
 332         /* reserve mailbox for vf use */
 333         p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
 334         if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
 335                 ret_val = 0;
 336
 337         return ret_val;
 338 }
 339
 340 /**
 341  *  igb_write_mbx_pf - Places a message in the mailbox
 342  *  @hw: pointer to the HW structure
 343  *  @msg: The message buffer
 344  *  @size: Length of buffer
 345  *  @vf_number: the VF index
 346  *
 347  *  returns SUCCESS if it successfully copied message into the buffer
 348  **/
 349 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 350                               u16 vf_number)
 351 {
 352         s32 ret_val;
 353         u16 i;
 354
 355         /* lock the mailbox to prevent pf/vf race condition */
 356         ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
 357         if (ret_val)
 358                 goto out_no_write;
 359
 360         /* flush msg and acks as we are overwriting the message buffer */
 361         igb_check_for_msg_pf(hw, vf_number);
 362         igb_check_for_ack_pf(hw, vf_number);
 363
 364         /* copy the caller specified message to the mailbox memory buffer */
 365         for (i = 0; i < size; i++)
 366                 array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);
 367
 368         /* Interrupt VF to tell it a message has been sent and release buffer*/
 369         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
 370
 371         /* update stats */
 372         hw->mbx.stats.msgs_tx++;
 373
 374 out_no_write:
 375         return ret_val;
 376
 377 }
 378
 379 /**
 380  *  igb_read_mbx_pf - Read a message from the mailbox
 381  *  @hw: pointer to the HW structure
 382  *  @msg: The message buffer
 383  *  @size: Length of buffer
 384  *  @vf_number: the VF index
 385  *
 386  *  This function copies a message from the mailbox buffer to the caller's
 387  *  memory buffer.  The presumption is that the caller knows that there was
 388  *  a message due to a VF request so no polling for message is needed.
 389  **/
 390 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
 391                              u16 vf_number)
 392 {
 393         s32 ret_val;
 394         u16 i;
 395
 396         /* lock the mailbox to prevent pf/vf race condition */
 397         ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
 398         if (ret_val)
 399                 goto out_no_read;
 400
 401         /* copy the message to the mailbox memory buffer */
 402         for (i = 0; i < size; i++)
 403                 msg[i] = array_rd32(E1000_VMBMEM(vf_number), i);
 404
 405         /* Acknowledge the message and release buffer */
 406         wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
 407
 408         /* update stats */
 409         hw->mbx.stats.msgs_rx++;
 410
 411 out_no_read:
 412         return ret_val;
 413 }
 414
 415 /**
 416  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
 417  *  @hw: pointer to the HW structure
 418  *
 419  *  Initializes the hw->mbx struct to correct values for pf mailbox
 420  */
 421 s32 igb_init_mbx_params_pf(struct e1000_hw *hw)
 422 {
 423         struct e1000_mbx_info *mbx = &hw->mbx;
 424
 425         mbx->timeout = 0;
 426         mbx->usec_delay = 0;
 427
 428         mbx->size = E1000_VFMAILBOX_SIZE;
 429
 430         mbx->ops.read = igb_read_mbx_pf;
 431         mbx->ops.write = igb_write_mbx_pf;
 432         mbx->ops.read_posted = igb_read_posted_mbx;
 433         mbx->ops.write_posted = igb_write_posted_mbx;
 434         mbx->ops.check_for_msg = igb_check_for_msg_pf;
 435         mbx->ops.check_for_ack = igb_check_for_ack_pf;
 436         mbx->ops.check_for_rst = igb_check_for_rst_pf;
 437
 438         mbx->stats.msgs_tx = 0;
 439         mbx->stats.msgs_rx = 0;
 440         mbx->stats.reqs = 0;
 441         mbx->stats.acks = 0;
 442         mbx->stats.rsts = 0;
 443
 444         return 0;
 445 }
 446