drivers/net/ethernet/intel/ixgbevf/mbx.c

   1 /*******************************************************************************
   2
   3   Intel 82599 Virtual Function driver
   4   Copyright(c) 1999 - 2012 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 "mbx.h"
  29 #include "ixgbevf.h"
  30
  31 /**
  32  *  ixgbevf_poll_for_msg - Wait for message notification
  33  *  @hw: pointer to the HW structure
  34  *
  35  *  returns 0 if it successfully received a message notification
  36  **/
  37 static s32 ixgbevf_poll_for_msg(struct ixgbe_hw *hw)
  38 {
  39         struct ixgbe_mbx_info *mbx = &hw->mbx;
  40         int countdown = mbx->timeout;
  41
  42         while (countdown && mbx->ops.check_for_msg(hw)) {
  43                 countdown--;
  44                 udelay(mbx->udelay);
  45         }
  46
  47         /* if we failed, all future posted messages fail until reset */
  48         if (!countdown)
  49                 mbx->timeout = 0;
  50
  51         return countdown ? 0 : IXGBE_ERR_MBX;
  52 }
  53
  54 /**
  55  *  ixgbevf_poll_for_ack - Wait for message acknowledgement
  56  *  @hw: pointer to the HW structure
  57  *
  58  *  returns 0 if it successfully received a message acknowledgement
  59  **/
  60 static s32 ixgbevf_poll_for_ack(struct ixgbe_hw *hw)
  61 {
  62         struct ixgbe_mbx_info *mbx = &hw->mbx;
  63         int countdown = mbx->timeout;
  64
  65         while (countdown && mbx->ops.check_for_ack(hw)) {
  66                 countdown--;
  67                 udelay(mbx->udelay);
  68         }
  69
  70         /* if we failed, all future posted messages fail until reset */
  71         if (!countdown)
  72                 mbx->timeout = 0;
  73
  74         return countdown ? 0 : IXGBE_ERR_MBX;
  75 }
  76
  77 /**
  78  *  ixgbevf_read_posted_mbx - Wait for message notification and receive message
  79  *  @hw: pointer to the HW structure
  80  *  @msg: The message buffer
  81  *  @size: Length of buffer
  82  *
  83  *  returns 0 if it successfully received a message notification and
  84  *  copied it into the receive buffer.
  85  **/
  86 static s32 ixgbevf_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
  87 {
  88         struct ixgbe_mbx_info *mbx = &hw->mbx;
  89         s32 ret_val = -IXGBE_ERR_MBX;
  90
  91         if (!mbx->ops.read)
  92                 goto out;
  93
  94         ret_val = ixgbevf_poll_for_msg(hw);
  95
  96         /* if ack received read message, otherwise we timed out */
  97         if (!ret_val)
  98                 ret_val = mbx->ops.read(hw, msg, size);
  99 out:
 100         return ret_val;
 101 }
 102
 103 /**
 104  *  ixgbevf_write_posted_mbx - Write a message to the mailbox, wait for ack
 105  *  @hw: pointer to the HW structure
 106  *  @msg: The message buffer
 107  *  @size: Length of buffer
 108  *
 109  *  returns 0 if it successfully copied message into the buffer and
 110  *  received an ack to that message within delay * timeout period
 111  **/
 112 static s32 ixgbevf_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
 113 {
 114         struct ixgbe_mbx_info *mbx = &hw->mbx;
 115         s32 ret_val = -IXGBE_ERR_MBX;
 116
 117         /* exit if either we can't write or there isn't a defined timeout */
 118         if (!mbx->ops.write || !mbx->timeout)
 119                 goto out;
 120
 121         /* send msg */
 122         ret_val = mbx->ops.write(hw, msg, size);
 123
 124         /* if msg sent wait until we receive an ack */
 125         if (!ret_val)
 126                 ret_val = ixgbevf_poll_for_ack(hw);
 127 out:
 128         return ret_val;
 129 }
 130
 131 /**
 132  *  ixgbevf_read_v2p_mailbox - read v2p mailbox
 133  *  @hw: pointer to the HW structure
 134  *
 135  *  This function is used to read the v2p mailbox without losing the read to
 136  *  clear status bits.
 137  **/
 138 static u32 ixgbevf_read_v2p_mailbox(struct ixgbe_hw *hw)
 139 {
 140         u32 v2p_mailbox = IXGBE_READ_REG(hw, IXGBE_VFMAILBOX);
 141
 142         v2p_mailbox |= hw->mbx.v2p_mailbox;
 143         hw->mbx.v2p_mailbox |= v2p_mailbox & IXGBE_VFMAILBOX_R2C_BITS;
 144
 145         return v2p_mailbox;
 146 }
 147
 148 /**
 149  *  ixgbevf_check_for_bit_vf - Determine if a status bit was set
 150  *  @hw: pointer to the HW structure
 151  *  @mask: bitmask for bits to be tested and cleared
 152  *
 153  *  This function is used to check for the read to clear bits within
 154  *  the V2P mailbox.
 155  **/
 156 static s32 ixgbevf_check_for_bit_vf(struct ixgbe_hw *hw, u32 mask)
 157 {
 158         u32 v2p_mailbox = ixgbevf_read_v2p_mailbox(hw);
 159         s32 ret_val = IXGBE_ERR_MBX;
 160
 161         if (v2p_mailbox & mask)
 162                 ret_val = 0;
 163
 164         hw->mbx.v2p_mailbox &= ~mask;
 165
 166         return ret_val;
 167 }
 168
 169 /**
 170  *  ixgbevf_check_for_msg_vf - checks to see if the PF has sent mail
 171  *  @hw: pointer to the HW structure
 172  *
 173  *  returns 0 if the PF has set the Status bit or else ERR_MBX
 174  **/
 175 static s32 ixgbevf_check_for_msg_vf(struct ixgbe_hw *hw)
 176 {
 177         s32 ret_val = IXGBE_ERR_MBX;
 178
 179         if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFSTS)) {
 180                 ret_val = 0;
 181                 hw->mbx.stats.reqs++;
 182         }
 183
 184         return ret_val;
 185 }
 186
 187 /**
 188  *  ixgbevf_check_for_ack_vf - checks to see if the PF has ACK'd
 189  *  @hw: pointer to the HW structure
 190  *
 191  *  returns 0 if the PF has set the ACK bit or else ERR_MBX
 192  **/
 193 static s32 ixgbevf_check_for_ack_vf(struct ixgbe_hw *hw)
 194 {
 195         s32 ret_val = IXGBE_ERR_MBX;
 196
 197         if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFACK)) {
 198                 ret_val = 0;
 199                 hw->mbx.stats.acks++;
 200         }
 201
 202         return ret_val;
 203 }
 204
 205 /**
 206  *  ixgbevf_check_for_rst_vf - checks to see if the PF has reset
 207  *  @hw: pointer to the HW structure
 208  *
 209  *  returns true if the PF has set the reset done bit or else false
 210  **/
 211 static s32 ixgbevf_check_for_rst_vf(struct ixgbe_hw *hw)
 212 {
 213         s32 ret_val = IXGBE_ERR_MBX;
 214
 215         if (!ixgbevf_check_for_bit_vf(hw, (IXGBE_VFMAILBOX_RSTD |
 216                                          IXGBE_VFMAILBOX_RSTI))) {
 217                 ret_val = 0;
 218                 hw->mbx.stats.rsts++;
 219         }
 220
 221         return ret_val;
 222 }
 223
 224 /**
 225  *  ixgbevf_obtain_mbx_lock_vf - obtain mailbox lock
 226  *  @hw: pointer to the HW structure
 227  *
 228  *  return 0 if we obtained the mailbox lock
 229  **/
 230 static s32 ixgbevf_obtain_mbx_lock_vf(struct ixgbe_hw *hw)
 231 {
 232         s32 ret_val = IXGBE_ERR_MBX;
 233
 234         /* Take ownership of the buffer */
 235         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_VFU);
 236
 237         /* reserve mailbox for vf use */
 238         if (ixgbevf_read_v2p_mailbox(hw) & IXGBE_VFMAILBOX_VFU)
 239                 ret_val = 0;
 240
 241         return ret_val;
 242 }
 243
 244 /**
 245  *  ixgbevf_write_mbx_vf - Write a message to the mailbox
 246  *  @hw: pointer to the HW structure
 247  *  @msg: The message buffer
 248  *  @size: Length of buffer
 249  *
 250  *  returns 0 if it successfully copied message into the buffer
 251  **/
 252 static s32 ixgbevf_write_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
 253 {
 254         s32 ret_val;
 255         u16 i;
 256
 257
 258         /* lock the mailbox to prevent pf/vf race condition */
 259         ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
 260         if (ret_val)
 261                 goto out_no_write;
 262
 263         /* flush msg and acks as we are overwriting the message buffer */
 264         ixgbevf_check_for_msg_vf(hw);
 265         ixgbevf_check_for_ack_vf(hw);
 266
 267         /* copy the caller specified message to the mailbox memory buffer */
 268         for (i = 0; i < size; i++)
 269                 IXGBE_WRITE_REG_ARRAY(hw, IXGBE_VFMBMEM, i, msg[i]);
 270
 271         /* update stats */
 272         hw->mbx.stats.msgs_tx++;
 273
 274         /* Drop VFU and interrupt the PF to tell it a message has been sent */
 275         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_REQ);
 276
 277 out_no_write:
 278         return ret_val;
 279 }
 280
 281 /**
 282  *  ixgbevf_read_mbx_vf - Reads a message from the inbox intended for vf
 283  *  @hw: pointer to the HW structure
 284  *  @msg: The message buffer
 285  *  @size: Length of buffer
 286  *
 287  *  returns 0 if it successfully read message from buffer
 288  **/
 289 static s32 ixgbevf_read_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
 290 {
 291         s32 ret_val = 0;
 292         u16 i;
 293
 294         /* lock the mailbox to prevent pf/vf race condition */
 295         ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
 296         if (ret_val)
 297                 goto out_no_read;
 298
 299         /* copy the message from the mailbox memory buffer */
 300         for (i = 0; i < size; i++)
 301                 msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_VFMBMEM, i);
 302
 303         /* Acknowledge receipt and release mailbox, then we're done */
 304         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_ACK);
 305
 306         /* update stats */
 307         hw->mbx.stats.msgs_rx++;
 308
 309 out_no_read:
 310         return ret_val;
 311 }
 312
 313 /**
 314  *  ixgbevf_init_mbx_params_vf - set initial values for vf mailbox
 315  *  @hw: pointer to the HW structure
 316  *
 317  *  Initializes the hw->mbx struct to correct values for vf mailbox
 318  */
 319 static s32 ixgbevf_init_mbx_params_vf(struct ixgbe_hw *hw)
 320 {
 321         struct ixgbe_mbx_info *mbx = &hw->mbx;
 322
 323         /* start mailbox as timed out and let the reset_hw call set the timeout
 324          * value to begin communications */
 325         mbx->timeout = 0;
 326         mbx->udelay = IXGBE_VF_MBX_INIT_DELAY;
 327
 328         mbx->size = IXGBE_VFMAILBOX_SIZE;
 329
 330         mbx->stats.msgs_tx = 0;
 331         mbx->stats.msgs_rx = 0;
 332         mbx->stats.reqs = 0;
 333         mbx->stats.acks = 0;
 334         mbx->stats.rsts = 0;
 335
 336         return 0;
 337 }
 338
 339 const struct ixgbe_mbx_operations ixgbevf_mbx_ops = {
 340         .init_params   = ixgbevf_init_mbx_params_vf,
 341         .read          = ixgbevf_read_mbx_vf,
 342         .write         = ixgbevf_write_mbx_vf,
 343         .read_posted   = ixgbevf_read_posted_mbx,
 344         .write_posted  = ixgbevf_write_posted_mbx,
 345         .check_for_msg = ixgbevf_check_for_msg_vf,
 346         .check_for_ack = ixgbevf_check_for_ack_vf,
 347         .check_for_rst = ixgbevf_check_for_rst_vf,
 348 };
 349