drivers/net/ethernet/intel/ixgbe/ixgbe_mbx.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright(c) 1999 - 2018 Intel Corporation. */
   3
   4 #include <linux/pci.h>
   5 #include <linux/delay.h>
   6 #include "ixgbe.h"
   7 #include "ixgbe_mbx.h"
   8
   9 /**
  10  *  ixgbe_read_mbx - Reads a message from the mailbox
  11  *  @hw: pointer to the HW structure
  12  *  @msg: The message buffer
  13  *  @size: Length of buffer
  14  *  @mbx_id: id of mailbox to read
  15  *
  16  *  returns SUCCESS if it successfully read message from buffer
  17  **/
  18 s32 ixgbe_read_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
  19 {
  20         struct ixgbe_mbx_info *mbx = &hw->mbx;
  21
  22         /* limit read to size of mailbox */
  23         if (size > mbx->size)
  24                 size = mbx->size;
  25
  26         if (!mbx->ops)
  27                 return IXGBE_ERR_MBX;
  28
  29         return mbx->ops->read(hw, msg, size, mbx_id);
  30 }
  31
  32 /**
  33  *  ixgbe_write_mbx - Write a message to the mailbox
  34  *  @hw: pointer to the HW structure
  35  *  @msg: The message buffer
  36  *  @size: Length of buffer
  37  *  @mbx_id: id of mailbox to write
  38  *
  39  *  returns SUCCESS if it successfully copied message into the buffer
  40  **/
  41 s32 ixgbe_write_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
  42 {
  43         struct ixgbe_mbx_info *mbx = &hw->mbx;
  44
  45         if (size > mbx->size)
  46                 return IXGBE_ERR_MBX;
  47
  48         if (!mbx->ops)
  49                 return IXGBE_ERR_MBX;
  50
  51         return mbx->ops->write(hw, msg, size, mbx_id);
  52 }
  53
  54 /**
  55  *  ixgbe_check_for_msg - checks to see if someone sent us mail
  56  *  @hw: pointer to the HW structure
  57  *  @mbx_id: id of mailbox to check
  58  *
  59  *  returns SUCCESS if the Status bit was found or else ERR_MBX
  60  **/
  61 s32 ixgbe_check_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
  62 {
  63         struct ixgbe_mbx_info *mbx = &hw->mbx;
  64
  65         if (!mbx->ops)
  66                 return IXGBE_ERR_MBX;
  67
  68         return mbx->ops->check_for_msg(hw, mbx_id);
  69 }
  70
  71 /**
  72  *  ixgbe_check_for_ack - checks to see if someone sent us ACK
  73  *  @hw: pointer to the HW structure
  74  *  @mbx_id: id of mailbox to check
  75  *
  76  *  returns SUCCESS if the Status bit was found or else ERR_MBX
  77  **/
  78 s32 ixgbe_check_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
  79 {
  80         struct ixgbe_mbx_info *mbx = &hw->mbx;
  81
  82         if (!mbx->ops)
  83                 return IXGBE_ERR_MBX;
  84
  85         return mbx->ops->check_for_ack(hw, mbx_id);
  86 }
  87
  88 /**
  89  *  ixgbe_check_for_rst - checks to see if other side has reset
  90  *  @hw: pointer to the HW structure
  91  *  @mbx_id: id of mailbox to check
  92  *
  93  *  returns SUCCESS if the Status bit was found or else ERR_MBX
  94  **/
  95 s32 ixgbe_check_for_rst(struct ixgbe_hw *hw, u16 mbx_id)
  96 {
  97         struct ixgbe_mbx_info *mbx = &hw->mbx;
  98
  99         if (!mbx->ops)
 100                 return IXGBE_ERR_MBX;
 101
 102         return mbx->ops->check_for_rst(hw, mbx_id);
 103 }
 104
 105 /**
 106  *  ixgbe_poll_for_msg - Wait for message notification
 107  *  @hw: pointer to the HW structure
 108  *  @mbx_id: id of mailbox to write
 109  *
 110  *  returns SUCCESS if it successfully received a message notification
 111  **/
 112 static s32 ixgbe_poll_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
 113 {
 114         struct ixgbe_mbx_info *mbx = &hw->mbx;
 115         int countdown = mbx->timeout;
 116
 117         if (!countdown || !mbx->ops)
 118                 return IXGBE_ERR_MBX;
 119
 120         while (mbx->ops->check_for_msg(hw, mbx_id)) {
 121                 countdown--;
 122                 if (!countdown)
 123                         return IXGBE_ERR_MBX;
 124                 udelay(mbx->usec_delay);
 125         }
 126
 127         return 0;
 128 }
 129
 130 /**
 131  *  ixgbe_poll_for_ack - Wait for message acknowledgement
 132  *  @hw: pointer to the HW structure
 133  *  @mbx_id: id of mailbox to write
 134  *
 135  *  returns SUCCESS if it successfully received a message acknowledgement
 136  **/
 137 static s32 ixgbe_poll_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
 138 {
 139         struct ixgbe_mbx_info *mbx = &hw->mbx;
 140         int countdown = mbx->timeout;
 141
 142         if (!countdown || !mbx->ops)
 143                 return IXGBE_ERR_MBX;
 144
 145         while (mbx->ops->check_for_ack(hw, mbx_id)) {
 146                 countdown--;
 147                 if (!countdown)
 148                         return IXGBE_ERR_MBX;
 149                 udelay(mbx->usec_delay);
 150         }
 151
 152         return 0;
 153 }
 154
 155 /**
 156  *  ixgbe_read_posted_mbx - Wait for message notification and receive message
 157  *  @hw: pointer to the HW structure
 158  *  @msg: The message buffer
 159  *  @size: Length of buffer
 160  *  @mbx_id: id of mailbox to write
 161  *
 162  *  returns SUCCESS if it successfully received a message notification and
 163  *  copied it into the receive buffer.
 164  **/
 165 static s32 ixgbe_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
 166                                  u16 mbx_id)
 167 {
 168         struct ixgbe_mbx_info *mbx = &hw->mbx;
 169         s32 ret_val;
 170
 171         if (!mbx->ops)
 172                 return IXGBE_ERR_MBX;
 173
 174         ret_val = ixgbe_poll_for_msg(hw, mbx_id);
 175         if (ret_val)
 176                 return ret_val;
 177
 178         /* if ack received read message */
 179         return mbx->ops->read(hw, msg, size, mbx_id);
 180 }
 181
 182 /**
 183  *  ixgbe_write_posted_mbx - Write a message to the mailbox, wait for ack
 184  *  @hw: pointer to the HW structure
 185  *  @msg: The message buffer
 186  *  @size: Length of buffer
 187  *  @mbx_id: id of mailbox to write
 188  *
 189  *  returns SUCCESS if it successfully copied message into the buffer and
 190  *  received an ack to that message within delay * timeout period
 191  **/
 192 static s32 ixgbe_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
 193                            u16 mbx_id)
 194 {
 195         struct ixgbe_mbx_info *mbx = &hw->mbx;
 196         s32 ret_val;
 197
 198         /* exit if either we can't write or there isn't a defined timeout */
 199         if (!mbx->ops || !mbx->timeout)
 200                 return IXGBE_ERR_MBX;
 201
 202         /* send msg */
 203         ret_val = mbx->ops->write(hw, msg, size, mbx_id);
 204         if (ret_val)
 205                 return ret_val;
 206
 207         /* if msg sent wait until we receive an ack */
 208         return ixgbe_poll_for_ack(hw, mbx_id);
 209 }
 210
 211 static s32 ixgbe_check_for_bit_pf(struct ixgbe_hw *hw, u32 mask, s32 index)
 212 {
 213         u32 mbvficr = IXGBE_READ_REG(hw, IXGBE_MBVFICR(index));
 214
 215         if (mbvficr & mask) {
 216                 IXGBE_WRITE_REG(hw, IXGBE_MBVFICR(index), mask);
 217                 return 0;
 218         }
 219
 220         return IXGBE_ERR_MBX;
 221 }
 222
 223 /**
 224  *  ixgbe_check_for_msg_pf - checks to see if the VF has sent mail
 225  *  @hw: pointer to the HW structure
 226  *  @vf_number: the VF index
 227  *
 228  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 229  **/
 230 static s32 ixgbe_check_for_msg_pf(struct ixgbe_hw *hw, u16 vf_number)
 231 {
 232         s32 index = IXGBE_MBVFICR_INDEX(vf_number);
 233         u32 vf_bit = vf_number % 16;
 234
 235         if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFREQ_VF1 << vf_bit,
 236                                     index)) {
 237                 hw->mbx.stats.reqs++;
 238                 return 0;
 239         }
 240
 241         return IXGBE_ERR_MBX;
 242 }
 243
 244 /**
 245  *  ixgbe_check_for_ack_pf - checks to see if the VF has ACKed
 246  *  @hw: pointer to the HW structure
 247  *  @vf_number: the VF index
 248  *
 249  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 250  **/
 251 static s32 ixgbe_check_for_ack_pf(struct ixgbe_hw *hw, u16 vf_number)
 252 {
 253         s32 index = IXGBE_MBVFICR_INDEX(vf_number);
 254         u32 vf_bit = vf_number % 16;
 255
 256         if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFACK_VF1 << vf_bit,
 257                                     index)) {
 258                 hw->mbx.stats.acks++;
 259                 return 0;
 260         }
 261
 262         return IXGBE_ERR_MBX;
 263 }
 264
 265 /**
 266  *  ixgbe_check_for_rst_pf - checks to see if the VF has reset
 267  *  @hw: pointer to the HW structure
 268  *  @vf_number: the VF index
 269  *
 270  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
 271  **/
 272 static s32 ixgbe_check_for_rst_pf(struct ixgbe_hw *hw, u16 vf_number)
 273 {
 274         u32 reg_offset = (vf_number < 32) ? 0 : 1;
 275         u32 vf_shift = vf_number % 32;
 276         u32 vflre = 0;
 277
 278         switch (hw->mac.type) {
 279         case ixgbe_mac_82599EB:
 280                 vflre = IXGBE_READ_REG(hw, IXGBE_VFLRE(reg_offset));
 281                 break;
 282         case ixgbe_mac_X540:
 283         case ixgbe_mac_X550:
 284         case ixgbe_mac_X550EM_x:
 285         case ixgbe_mac_x550em_a:
 286                 vflre = IXGBE_READ_REG(hw, IXGBE_VFLREC(reg_offset));
 287                 break;
 288         default:
 289                 break;
 290         }
 291
 292         if (vflre & BIT(vf_shift)) {
 293                 IXGBE_WRITE_REG(hw, IXGBE_VFLREC(reg_offset), BIT(vf_shift));
 294                 hw->mbx.stats.rsts++;
 295                 return 0;
 296         }
 297
 298         return IXGBE_ERR_MBX;
 299 }
 300
 301 /**
 302  *  ixgbe_obtain_mbx_lock_pf - obtain mailbox lock
 303  *  @hw: pointer to the HW structure
 304  *  @vf_number: the VF index
 305  *
 306  *  return SUCCESS if we obtained the mailbox lock
 307  **/
 308 static s32 ixgbe_obtain_mbx_lock_pf(struct ixgbe_hw *hw, u16 vf_number)
 309 {
 310         u32 p2v_mailbox;
 311
 312         /* Take ownership of the buffer */
 313         IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_PFU);
 314
 315         /* reserve mailbox for vf use */
 316         p2v_mailbox = IXGBE_READ_REG(hw, IXGBE_PFMAILBOX(vf_number));
 317         if (p2v_mailbox & IXGBE_PFMAILBOX_PFU)
 318                 return 0;
 319
 320         return IXGBE_ERR_MBX;
 321 }
 322
 323 /**
 324  *  ixgbe_write_mbx_pf - Places a message in the mailbox
 325  *  @hw: pointer to the HW structure
 326  *  @msg: The message buffer
 327  *  @size: Length of buffer
 328  *  @vf_number: the VF index
 329  *
 330  *  returns SUCCESS if it successfully copied message into the buffer
 331  **/
 332 static s32 ixgbe_write_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
 333                               u16 vf_number)
 334 {
 335         s32 ret_val;
 336         u16 i;
 337
 338         /* lock the mailbox to prevent pf/vf race condition */
 339         ret_val = ixgbe_obtain_mbx_lock_pf(hw, vf_number);
 340         if (ret_val)
 341                 return ret_val;
 342
 343         /* flush msg and acks as we are overwriting the message buffer */
 344         ixgbe_check_for_msg_pf(hw, vf_number);
 345         ixgbe_check_for_ack_pf(hw, vf_number);
 346
 347         /* copy the caller specified message to the mailbox memory buffer */
 348         for (i = 0; i < size; i++)
 349                 IXGBE_WRITE_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i, msg[i]);
 350
 351         /* Interrupt VF to tell it a message has been sent and release buffer*/
 352         IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_STS);
 353
 354         /* update stats */
 355         hw->mbx.stats.msgs_tx++;
 356
 357         return 0;
 358 }
 359
 360 /**
 361  *  ixgbe_read_mbx_pf - Read a message from the mailbox
 362  *  @hw: pointer to the HW structure
 363  *  @msg: The message buffer
 364  *  @size: Length of buffer
 365  *  @vf_number: the VF index
 366  *
 367  *  This function copies a message from the mailbox buffer to the caller's
 368  *  memory buffer.  The presumption is that the caller knows that there was
 369  *  a message due to a VF request so no polling for message is needed.
 370  **/
 371 static s32 ixgbe_read_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
 372                              u16 vf_number)
 373 {
 374         s32 ret_val;
 375         u16 i;
 376
 377         /* lock the mailbox to prevent pf/vf race condition */
 378         ret_val = ixgbe_obtain_mbx_lock_pf(hw, vf_number);
 379         if (ret_val)
 380                 return ret_val;
 381
 382         /* copy the message to the mailbox memory buffer */
 383         for (i = 0; i < size; i++)
 384                 msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i);
 385
 386         /* Acknowledge the message and release buffer */
 387         IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_ACK);
 388
 389         /* update stats */
 390         hw->mbx.stats.msgs_rx++;
 391
 392         return 0;
 393 }
 394
 395 #ifdef CONFIG_PCI_IOV
 396 /**
 397  *  ixgbe_init_mbx_params_pf - set initial values for pf mailbox
 398  *  @hw: pointer to the HW structure
 399  *
 400  *  Initializes the hw->mbx struct to correct values for pf mailbox
 401  */
 402 void ixgbe_init_mbx_params_pf(struct ixgbe_hw *hw)
 403 {
 404         struct ixgbe_mbx_info *mbx = &hw->mbx;
 405
 406         if (hw->mac.type != ixgbe_mac_82599EB &&
 407             hw->mac.type != ixgbe_mac_X550 &&
 408             hw->mac.type != ixgbe_mac_X550EM_x &&
 409             hw->mac.type != ixgbe_mac_x550em_a &&
 410             hw->mac.type != ixgbe_mac_X540)
 411                 return;
 412
 413         mbx->timeout = 0;
 414         mbx->usec_delay = 0;
 415
 416         mbx->stats.msgs_tx = 0;
 417         mbx->stats.msgs_rx = 0;
 418         mbx->stats.reqs = 0;
 419         mbx->stats.acks = 0;
 420         mbx->stats.rsts = 0;
 421
 422         mbx->size = IXGBE_VFMAILBOX_SIZE;
 423 }
 424 #endif /* CONFIG_PCI_IOV */
 425
 426 const struct ixgbe_mbx_operations mbx_ops_generic = {
 427         .read                   = ixgbe_read_mbx_pf,
 428         .write                  = ixgbe_write_mbx_pf,
 429         .read_posted            = ixgbe_read_posted_mbx,
 430         .write_posted           = ixgbe_write_posted_mbx,
 431         .check_for_msg          = ixgbe_check_for_msg_pf,
 432         .check_for_ack          = ixgbe_check_for_ack_pf,
 433         .check_for_rst          = ixgbe_check_for_rst_pf,
 434 };
 435