r6040: fix link checking with switches

[safe/jmp/linux-2.6] / drivers / net / igb / e1000_mbx.c

diff --git a/drivers/net/igb/e1000_mbx.c b/drivers/net/igb/e1000_mbx.c
index 840782f..c474cdb 100644 (file)
--- a/drivers/net/igb/e1000_mbx.c
+++ b/drivers/net/igb/e1000_mbx.c
@@ -140,15 +140,19 @@ static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
        struct e1000_mbx_info *mbx = &hw->mbx;
        int countdown = mbx->timeout;
 
-       if (!mbx->ops.check_for_msg)
+       if (!countdown || !mbx->ops.check_for_msg)
                goto out;
 
-       while (mbx->ops.check_for_msg(hw, mbx_id)) {
+       while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
+               countdown--;
                if (!countdown)
                        break;
-               countdown--;
                udelay(mbx->usec_delay);
        }
+
+       /* if we failed, all future posted messages fail until reset */
+       if (!countdown)
+               mbx->timeout = 0;
 out:
        return countdown ? 0 : -E1000_ERR_MBX;
 }
@@ -165,15 +169,19 @@ static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
        struct e1000_mbx_info *mbx = &hw->mbx;
        int countdown = mbx->timeout;
 
-       if (!mbx->ops.check_for_ack)
+       if (!countdown || !mbx->ops.check_for_ack)
                goto out;
 
-       while (mbx->ops.check_for_ack(hw, mbx_id)) {
+       while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
+               countdown--;
                if (!countdown)
                        break;
-               countdown--;
                udelay(mbx->usec_delay);
        }
+
+       /* if we failed, all future posted messages fail until reset */
+       if (!countdown)
+               mbx->timeout = 0;
 out:
        return countdown ? 0 : -E1000_ERR_MBX;
 }
@@ -217,12 +225,13 @@ out:
 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
 {
        struct e1000_mbx_info *mbx = &hw->mbx;
-       s32 ret_val = 0;
+       s32 ret_val = -E1000_ERR_MBX;
 
-       if (!mbx->ops.write)
+       /* exit if either we can't write or there isn't a defined timeout */
+       if (!mbx->ops.write || !mbx->timeout)
                goto out;
 
-       /* send msg*/
+       /* send msg */
        ret_val = mbx->ops.write(hw, msg, size, mbx_id);
 
        /* if msg sent wait until we receive an ack */
@@ -305,6 +314,30 @@ static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
 }
 
 /**
+ *  igb_obtain_mbx_lock_pf - obtain mailbox lock
+ *  @hw: pointer to the HW structure
+ *  @vf_number: the VF index
+ *
+ *  return SUCCESS if we obtained the mailbox lock
+ **/
+static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
+{
+       s32 ret_val = -E1000_ERR_MBX;
+       u32 p2v_mailbox;
+
+
+       /* Take ownership of the buffer */
+       wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
+
+       /* reserve mailbox for vf use */
+       p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
+       if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
+               ret_val = 0;
+
+       return ret_val;
+}
+
+/**
  *  igb_write_mbx_pf - Places a message in the mailbox
  *  @hw: pointer to the HW structure
  *  @msg: The message buffer
@@ -316,27 +349,17 @@ static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
                               u16 vf_number)
 {
-       u32 p2v_mailbox;
-       s32 ret_val = 0;
+       s32 ret_val;
        u16 i;
 
-       /* Take ownership of the buffer */
-       wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
-
-       /* Make sure we have ownership now... */
-       p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
-       if (!(p2v_mailbox & E1000_P2VMAILBOX_PFU)) {
-               /* failed to grab ownership */
-               ret_val = -E1000_ERR_MBX;
+       /* lock the mailbox to prevent pf/vf race condition */
+       ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
+       if (ret_val)
                goto out_no_write;
-       }
 
-       /*
-        * flush any ack or msg which may already be in the queue
-        * as they are likely the result of an error
-        */
-       igb_check_for_ack_pf(hw, vf_number);
+       /* flush msg and acks as we are overwriting the message buffer */
        igb_check_for_msg_pf(hw, vf_number);
+       igb_check_for_ack_pf(hw, vf_number);
 
        /* copy the caller specified message to the mailbox memory buffer */
        for (i = 0; i < size; i++)
@@ -367,20 +390,13 @@ out_no_write:
 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
                              u16 vf_number)
 {
-       u32 p2v_mailbox;
-       s32 ret_val = 0;
+       s32 ret_val;
        u16 i;
 
-       /* Take ownership of the buffer */
-       wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
-
-       /* Make sure we have ownership now... */
-       p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
-       if (!(p2v_mailbox & E1000_P2VMAILBOX_PFU)) {
-               /* failed to grab ownership */
-               ret_val = -E1000_ERR_MBX;
+       /* lock the mailbox to prevent pf/vf race condition */
+       ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
+       if (ret_val)
                goto out_no_read;
-       }
 
        /* copy the message to the mailbox memory buffer */
        for (i = 0; i < size; i++)
@@ -392,8 +408,6 @@ static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
        /* update stats */
        hw->mbx.stats.msgs_rx++;
 
-       ret_val = 0;
-
 out_no_read:
        return ret_val;
 }