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         ret_val = ixgbevf_poll_for_msg(hw);
  92
  93         /* if ack received read message, otherwise we timed out */
  94         if (!ret_val)
  95                 ret_val = mbx->ops.read(hw, msg, size);
  96
  97         return ret_val;
  98 }
  99
 100 /**
 101  *  ixgbevf_write_posted_mbx - Write a message to the mailbox, wait for ack
 102  *  @hw: pointer to the HW structure
 103  *  @msg: The message buffer
 104  *  @size: Length of buffer
 105  *
 106  *  returns 0 if it successfully copied message into the buffer and
 107  *  received an ack to that message within delay * timeout period
 108  **/
 109 static s32 ixgbevf_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
 110 {
 111         struct ixgbe_mbx_info *mbx = &hw->mbx;
 112         s32 ret_val;
 113
 114         /* send msg */
 115         ret_val = mbx->ops.write(hw, msg, size);
 116
 117         /* if msg sent wait until we receive an ack */
 118         if (!ret_val)
 119                 ret_val = ixgbevf_poll_for_ack(hw);
 120
 121         return ret_val;
 122 }
 123
 124 /**
 125  *  ixgbevf_read_v2p_mailbox - read v2p mailbox
 126  *  @hw: pointer to the HW structure
 127  *
 128  *  This function is used to read the v2p mailbox without losing the read to
 129  *  clear status bits.
 130  **/
 131 static u32 ixgbevf_read_v2p_mailbox(struct ixgbe_hw *hw)
 132 {
 133         u32 v2p_mailbox = IXGBE_READ_REG(hw, IXGBE_VFMAILBOX);
 134
 135         v2p_mailbox |= hw->mbx.v2p_mailbox;
 136         hw->mbx.v2p_mailbox |= v2p_mailbox & IXGBE_VFMAILBOX_R2C_BITS;
 137
 138         return v2p_mailbox;
 139 }
 140
 141 /**
 142  *  ixgbevf_check_for_bit_vf - Determine if a status bit was set
 143  *  @hw: pointer to the HW structure
 144  *  @mask: bitmask for bits to be tested and cleared
 145  *
 146  *  This function is used to check for the read to clear bits within
 147  *  the V2P mailbox.
 148  **/
 149 static s32 ixgbevf_check_for_bit_vf(struct ixgbe_hw *hw, u32 mask)
 150 {
 151         u32 v2p_mailbox = ixgbevf_read_v2p_mailbox(hw);
 152         s32 ret_val = IXGBE_ERR_MBX;
 153
 154         if (v2p_mailbox & mask)
 155                 ret_val = 0;
 156
 157         hw->mbx.v2p_mailbox &= ~mask;
 158
 159         return ret_val;
 160 }
 161
 162 /**
 163  *  ixgbevf_check_for_msg_vf - checks to see if the PF has sent mail
 164  *  @hw: pointer to the HW structure
 165  *
 166  *  returns 0 if the PF has set the Status bit or else ERR_MBX
 167  **/
 168 static s32 ixgbevf_check_for_msg_vf(struct ixgbe_hw *hw)
 169 {
 170         s32 ret_val = IXGBE_ERR_MBX;
 171
 172         if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFSTS)) {
 173                 ret_val = 0;
 174                 hw->mbx.stats.reqs++;
 175         }
 176
 177         return ret_val;
 178 }
 179
 180 /**
 181  *  ixgbevf_check_for_ack_vf - checks to see if the PF has ACK'd
 182  *  @hw: pointer to the HW structure
 183  *
 184  *  returns 0 if the PF has set the ACK bit or else ERR_MBX
 185  **/
 186 static s32 ixgbevf_check_for_ack_vf(struct ixgbe_hw *hw)
 187 {
 188         s32 ret_val = IXGBE_ERR_MBX;
 189
 190         if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFACK)) {
 191                 ret_val = 0;
 192                 hw->mbx.stats.acks++;
 193         }
 194
 195         return ret_val;
 196 }
 197
 198 /**
 199  *  ixgbevf_check_for_rst_vf - checks to see if the PF has reset
 200  *  @hw: pointer to the HW structure
 201  *
 202  *  returns true if the PF has set the reset done bit or else false
 203  **/
 204 static s32 ixgbevf_check_for_rst_vf(struct ixgbe_hw *hw)
 205 {
 206         s32 ret_val = IXGBE_ERR_MBX;
 207
 208         if (!ixgbevf_check_for_bit_vf(hw, (IXGBE_VFMAILBOX_RSTD |
 209                                          IXGBE_VFMAILBOX_RSTI))) {
 210                 ret_val = 0;
 211                 hw->mbx.stats.rsts++;
 212         }
 213
 214         return ret_val;
 215 }
 216
 217 /**
 218  *  ixgbevf_obtain_mbx_lock_vf - obtain mailbox lock
 219  *  @hw: pointer to the HW structure
 220  *
 221  *  return 0 if we obtained the mailbox lock
 222  **/
 223 static s32 ixgbevf_obtain_mbx_lock_vf(struct ixgbe_hw *hw)
 224 {
 225         s32 ret_val = IXGBE_ERR_MBX;
 226
 227         /* Take ownership of the buffer */
 228         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_VFU);
 229
 230         /* reserve mailbox for vf use */
 231         if (ixgbevf_read_v2p_mailbox(hw) & IXGBE_VFMAILBOX_VFU)
 232                 ret_val = 0;
 233
 234         return ret_val;
 235 }
 236
 237 /**
 238  *  ixgbevf_write_mbx_vf - Write a message to the mailbox
 239  *  @hw: pointer to the HW structure
 240  *  @msg: The message buffer
 241  *  @size: Length of buffer
 242  *
 243  *  returns 0 if it successfully copied message into the buffer
 244  **/
 245 static s32 ixgbevf_write_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
 246 {
 247         s32 ret_val;
 248         u16 i;
 249
 250
 251         /* lock the mailbox to prevent pf/vf race condition */
 252         ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
 253         if (ret_val)
 254                 goto out_no_write;
 255
 256         /* flush msg and acks as we are overwriting the message buffer */
 257         ixgbevf_check_for_msg_vf(hw);
 258         ixgbevf_check_for_ack_vf(hw);
 259
 260         /* copy the caller specified message to the mailbox memory buffer */
 261         for (i = 0; i < size; i++)
 262                 IXGBE_WRITE_REG_ARRAY(hw, IXGBE_VFMBMEM, i, msg[i]);
 263
 264         /* update stats */
 265         hw->mbx.stats.msgs_tx++;
 266
 267         /* Drop VFU and interrupt the PF to tell it a message has been sent */
 268         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_REQ);
 269
 270 out_no_write:
 271         return ret_val;
 272 }
 273
 274 /**
 275  *  ixgbevf_read_mbx_vf - Reads a message from the inbox intended for vf
 276  *  @hw: pointer to the HW structure
 277  *  @msg: The message buffer
 278  *  @size: Length of buffer
 279  *
 280  *  returns 0 if it successfully read message from buffer
 281  **/
 282 static s32 ixgbevf_read_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
 283 {
 284         s32 ret_val = 0;
 285         u16 i;
 286
 287         /* lock the mailbox to prevent pf/vf race condition */
 288         ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
 289         if (ret_val)
 290                 goto out_no_read;
 291
 292         /* copy the message from the mailbox memory buffer */
 293         for (i = 0; i < size; i++)
 294                 msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_VFMBMEM, i);
 295
 296         /* Acknowledge receipt and release mailbox, then we're done */
 297         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_ACK);
 298
 299         /* update stats */
 300         hw->mbx.stats.msgs_rx++;
 301
 302 out_no_read:
 303         return ret_val;
 304 }
 305
 306 /**
 307  *  ixgbevf_init_mbx_params_vf - set initial values for vf mailbox
 308  *  @hw: pointer to the HW structure
 309  *
 310  *  Initializes the hw->mbx struct to correct values for vf mailbox
 311  */
 312 static s32 ixgbevf_init_mbx_params_vf(struct ixgbe_hw *hw)
 313 {
 314         struct ixgbe_mbx_info *mbx = &hw->mbx;
 315
 316         /* start mailbox as timed out and let the reset_hw call set the timeout
 317          * value to begin communications */
 318         mbx->timeout = 0;
 319         mbx->udelay = IXGBE_VF_MBX_INIT_DELAY;
 320
 321         mbx->size = IXGBE_VFMAILBOX_SIZE;
 322
 323         mbx->stats.msgs_tx = 0;
 324         mbx->stats.msgs_rx = 0;
 325         mbx->stats.reqs = 0;
 326         mbx->stats.acks = 0;
 327         mbx->stats.rsts = 0;
 328
 329         return 0;
 330 }
 331
 332 const struct ixgbe_mbx_operations ixgbevf_mbx_ops = {
 333         .init_params   = ixgbevf_init_mbx_params_vf,
 334         .read          = ixgbevf_read_mbx_vf,
 335         .write         = ixgbevf_write_mbx_vf,
 336         .read_posted   = ixgbevf_read_posted_mbx,
 337         .write_posted  = ixgbevf_write_posted_mbx,
 338         .check_for_msg = ixgbevf_check_for_msg_vf,
 339         .check_for_ack = ixgbevf_check_for_ack_vf,
 340         .check_for_rst = ixgbevf_check_for_rst_vf,
 341 };
 342