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

   1 /*******************************************************************************
   2
   3   Intel 82599 Virtual Function driver
   4   Copyright(c) 1999 - 2010 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
  30 /**
  31  *  ixgbevf_poll_for_msg - Wait for message notification
  32  *  @hw: pointer to the HW structure
  33  *
  34  *  returns 0 if it successfully received a message notification
  35  **/
  36 static s32 ixgbevf_poll_for_msg(struct ixgbe_hw *hw)
  37 {
  38         struct ixgbe_mbx_info *mbx = &hw->mbx;
  39         int countdown = mbx->timeout;
  40
  41         while (countdown && mbx->ops.check_for_msg(hw)) {
  42                 countdown--;
  43                 udelay(mbx->udelay);
  44         }
  45
  46         /* if we failed, all future posted messages fail until reset */
  47         if (!countdown)
  48                 mbx->timeout = 0;
  49
  50         return countdown ? 0 : IXGBE_ERR_MBX;
  51 }
  52
  53 /**
  54  *  ixgbevf_poll_for_ack - Wait for message acknowledgement
  55  *  @hw: pointer to the HW structure
  56  *
  57  *  returns 0 if it successfully received a message acknowledgement
  58  **/
  59 static s32 ixgbevf_poll_for_ack(struct ixgbe_hw *hw)
  60 {
  61         struct ixgbe_mbx_info *mbx = &hw->mbx;
  62         int countdown = mbx->timeout;
  63
  64         while (countdown && mbx->ops.check_for_ack(hw)) {
  65                 countdown--;
  66                 udelay(mbx->udelay);
  67         }
  68
  69         /* if we failed, all future posted messages fail until reset */
  70         if (!countdown)
  71                 mbx->timeout = 0;
  72
  73         return countdown ? 0 : IXGBE_ERR_MBX;
  74 }
  75
  76 /**
  77  *  ixgbevf_read_posted_mbx - Wait for message notification and receive message
  78  *  @hw: pointer to the HW structure
  79  *  @msg: The message buffer
  80  *  @size: Length of buffer
  81  *
  82  *  returns 0 if it successfully received a message notification and
  83  *  copied it into the receive buffer.
  84  **/
  85 static s32 ixgbevf_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
  86 {
  87         struct ixgbe_mbx_info *mbx = &hw->mbx;
  88         s32 ret_val = IXGBE_ERR_MBX;
  89
  90         ret_val = ixgbevf_poll_for_msg(hw);
  91
  92         /* if ack received read message, otherwise we timed out */
  93         if (!ret_val)
  94                 ret_val = mbx->ops.read(hw, msg, size);
  95
  96         return ret_val;
  97 }
  98
  99 /**
 100  *  ixgbevf_write_posted_mbx - Write a message to the mailbox, wait for ack
 101  *  @hw: pointer to the HW structure
 102  *  @msg: The message buffer
 103  *  @size: Length of buffer
 104  *
 105  *  returns 0 if it successfully copied message into the buffer and
 106  *  received an ack to that message within delay * timeout period
 107  **/
 108 static s32 ixgbevf_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
 109 {
 110         struct ixgbe_mbx_info *mbx = &hw->mbx;
 111         s32 ret_val;
 112
 113         /* send msg */
 114         ret_val = mbx->ops.write(hw, msg, size);
 115
 116         /* if msg sent wait until we receive an ack */
 117         if (!ret_val)
 118                 ret_val = ixgbevf_poll_for_ack(hw);
 119
 120         return ret_val;
 121 }
 122
 123 /**
 124  *  ixgbevf_read_v2p_mailbox - read v2p mailbox
 125  *  @hw: pointer to the HW structure
 126  *
 127  *  This function is used to read the v2p mailbox without losing the read to
 128  *  clear status bits.
 129  **/
 130 static u32 ixgbevf_read_v2p_mailbox(struct ixgbe_hw *hw)
 131 {
 132         u32 v2p_mailbox = IXGBE_READ_REG(hw, IXGBE_VFMAILBOX);
 133
 134         v2p_mailbox |= hw->mbx.v2p_mailbox;
 135         hw->mbx.v2p_mailbox |= v2p_mailbox & IXGBE_VFMAILBOX_R2C_BITS;
 136
 137         return v2p_mailbox;
 138 }
 139
 140 /**
 141  *  ixgbevf_check_for_bit_vf - Determine if a status bit was set
 142  *  @hw: pointer to the HW structure
 143  *  @mask: bitmask for bits to be tested and cleared
 144  *
 145  *  This function is used to check for the read to clear bits within
 146  *  the V2P mailbox.
 147  **/
 148 static s32 ixgbevf_check_for_bit_vf(struct ixgbe_hw *hw, u32 mask)
 149 {
 150         u32 v2p_mailbox = ixgbevf_read_v2p_mailbox(hw);
 151         s32 ret_val = IXGBE_ERR_MBX;
 152
 153         if (v2p_mailbox & mask)
 154                 ret_val = 0;
 155
 156         hw->mbx.v2p_mailbox &= ~mask;
 157
 158         return ret_val;
 159 }
 160
 161 /**
 162  *  ixgbevf_check_for_msg_vf - checks to see if the PF has sent mail
 163  *  @hw: pointer to the HW structure
 164  *
 165  *  returns 0 if the PF has set the Status bit or else ERR_MBX
 166  **/
 167 static s32 ixgbevf_check_for_msg_vf(struct ixgbe_hw *hw)
 168 {
 169         s32 ret_val = IXGBE_ERR_MBX;
 170
 171         if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFSTS)) {
 172                 ret_val = 0;
 173                 hw->mbx.stats.reqs++;
 174         }
 175
 176         return ret_val;
 177 }
 178
 179 /**
 180  *  ixgbevf_check_for_ack_vf - checks to see if the PF has ACK'd
 181  *  @hw: pointer to the HW structure
 182  *
 183  *  returns 0 if the PF has set the ACK bit or else ERR_MBX
 184  **/
 185 static s32 ixgbevf_check_for_ack_vf(struct ixgbe_hw *hw)
 186 {
 187         s32 ret_val = IXGBE_ERR_MBX;
 188
 189         if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFACK)) {
 190                 ret_val = 0;
 191                 hw->mbx.stats.acks++;
 192         }
 193
 194         return ret_val;
 195 }
 196
 197 /**
 198  *  ixgbevf_check_for_rst_vf - checks to see if the PF has reset
 199  *  @hw: pointer to the HW structure
 200  *
 201  *  returns true if the PF has set the reset done bit or else false
 202  **/
 203 static s32 ixgbevf_check_for_rst_vf(struct ixgbe_hw *hw)
 204 {
 205         s32 ret_val = IXGBE_ERR_MBX;
 206
 207         if (!ixgbevf_check_for_bit_vf(hw, (IXGBE_VFMAILBOX_RSTD |
 208                                          IXGBE_VFMAILBOX_RSTI))) {
 209                 ret_val = 0;
 210                 hw->mbx.stats.rsts++;
 211         }
 212
 213         return ret_val;
 214 }
 215
 216 /**
 217  *  ixgbevf_obtain_mbx_lock_vf - obtain mailbox lock
 218  *  @hw: pointer to the HW structure
 219  *
 220  *  return 0 if we obtained the mailbox lock
 221  **/
 222 static s32 ixgbevf_obtain_mbx_lock_vf(struct ixgbe_hw *hw)
 223 {
 224         s32 ret_val = IXGBE_ERR_MBX;
 225
 226         /* Take ownership of the buffer */
 227         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_VFU);
 228
 229         /* reserve mailbox for vf use */
 230         if (ixgbevf_read_v2p_mailbox(hw) & IXGBE_VFMAILBOX_VFU)
 231                 ret_val = 0;
 232
 233         return ret_val;
 234 }
 235
 236 /**
 237  *  ixgbevf_write_mbx_vf - Write a message to the mailbox
 238  *  @hw: pointer to the HW structure
 239  *  @msg: The message buffer
 240  *  @size: Length of buffer
 241  *
 242  *  returns 0 if it successfully copied message into the buffer
 243  **/
 244 static s32 ixgbevf_write_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
 245 {
 246         s32 ret_val;
 247         u16 i;
 248
 249
 250         /* lock the mailbox to prevent pf/vf race condition */
 251         ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
 252         if (ret_val)
 253                 goto out_no_write;
 254
 255         /* flush msg and acks as we are overwriting the message buffer */
 256         ixgbevf_check_for_msg_vf(hw);
 257         ixgbevf_check_for_ack_vf(hw);
 258
 259         /* copy the caller specified message to the mailbox memory buffer */
 260         for (i = 0; i < size; i++)
 261                 IXGBE_WRITE_REG_ARRAY(hw, IXGBE_VFMBMEM, i, msg[i]);
 262
 263         /* update stats */
 264         hw->mbx.stats.msgs_tx++;
 265
 266         /* Drop VFU and interrupt the PF to tell it a message has been sent */
 267         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_REQ);
 268
 269 out_no_write:
 270         return ret_val;
 271 }
 272
 273 /**
 274  *  ixgbevf_read_mbx_vf - Reads a message from the inbox intended for vf
 275  *  @hw: pointer to the HW structure
 276  *  @msg: The message buffer
 277  *  @size: Length of buffer
 278  *
 279  *  returns 0 if it successfully read message from buffer
 280  **/
 281 static s32 ixgbevf_read_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
 282 {
 283         s32 ret_val = 0;
 284         u16 i;
 285
 286         /* lock the mailbox to prevent pf/vf race condition */
 287         ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
 288         if (ret_val)
 289                 goto out_no_read;
 290
 291         /* copy the message from the mailbox memory buffer */
 292         for (i = 0; i < size; i++)
 293                 msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_VFMBMEM, i);
 294
 295         /* Acknowledge receipt and release mailbox, then we're done */
 296         IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_ACK);
 297
 298         /* update stats */
 299         hw->mbx.stats.msgs_rx++;
 300
 301 out_no_read:
 302         return ret_val;
 303 }
 304
 305 /**
 306  *  ixgbevf_init_mbx_params_vf - set initial values for vf mailbox
 307  *  @hw: pointer to the HW structure
 308  *
 309  *  Initializes the hw->mbx struct to correct values for vf mailbox
 310  */
 311 static s32 ixgbevf_init_mbx_params_vf(struct ixgbe_hw *hw)
 312 {
 313         struct ixgbe_mbx_info *mbx = &hw->mbx;
 314
 315         /* start mailbox as timed out and let the reset_hw call set the timeout
 316          * value to begin communications */
 317         mbx->timeout = 0;
 318         mbx->udelay = IXGBE_VF_MBX_INIT_DELAY;
 319
 320         mbx->size = IXGBE_VFMAILBOX_SIZE;
 321
 322         mbx->stats.msgs_tx = 0;
 323         mbx->stats.msgs_rx = 0;
 324         mbx->stats.reqs = 0;
 325         mbx->stats.acks = 0;
 326         mbx->stats.rsts = 0;
 327
 328         return 0;
 329 }
 330
 331 struct ixgbe_mbx_operations ixgbevf_mbx_ops = {
 332         .init_params   = ixgbevf_init_mbx_params_vf,
 333         .read          = ixgbevf_read_mbx_vf,
 334         .write         = ixgbevf_write_mbx_vf,
 335         .read_posted   = ixgbevf_read_posted_mbx,
 336         .write_posted  = ixgbevf_write_posted_mbx,
 337         .check_for_msg = ixgbevf_check_for_msg_vf,
 338         .check_for_ack = ixgbevf_check_for_ack_vf,
 339         .check_for_rst = ixgbevf_check_for_rst_vf,
 340 };
 341