igb: Add SMBI semaphore to I210/I211

It was previously thought that, since I210/I211 are single port devices,
they did not need the SMBI semaphore. This is not the case. Add support for
the SMBI semaphore.

Signed-off-by: Matthew Vick <matthew.vick@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

3 files changed, 43 insertions, 26 deletions

diff --git a/drivers/net/ethernet/intel/igb/e1000_82575.c b/drivers/net/ethernet/intel/igb/e1000_82575.c
index c9bba39d50bd..6cb0ca2869b9 100644
--- a/drivers/net/ethernet/intel/igb/e1000_82575.c
+++ b/drivers/net/ethernet/intel/igb/e1000_82575.c
@@ -389,6 +389,9 @@ static s32 igb_init_mac_params_82575(struct e1000_hw *hw)
                 dev_spec->eee_disable = false;
         else
                 dev_spec->eee_disable = true;
+        /* Allow a single clear of the SW semaphore on I210 and newer */
+        if (mac->type >= e1000_i210)
+                dev_spec->clear_semaphore_once = true;
         /* physical interface link setup */
         mac->ops.setup_physical_interface =
                 (hw->phy.media_type == e1000_media_type_copper)
diff --git a/drivers/net/ethernet/intel/igb/e1000_hw.h b/drivers/net/ethernet/intel/igb/e1000_hw.h
index 1138ccaf95ff..f1dbab920286 100644
--- a/drivers/net/ethernet/intel/igb/e1000_hw.h
+++ b/drivers/net/ethernet/intel/igb/e1000_hw.h
@@ -529,6 +529,7 @@ struct e1000_dev_spec_82575 {
         bool sgmii_active;
         bool global_device_reset;
         bool eee_disable;
+        bool clear_semaphore_once;
 };
 
 struct e1000_hw {
diff --git a/drivers/net/ethernet/intel/igb/e1000_i210.c b/drivers/net/ethernet/intel/igb/e1000_i210.c
index 9764cd3610e5..ddb3cf51b9b9 100644
--- a/drivers/net/ethernet/intel/igb/e1000_i210.c
+++ b/drivers/net/ethernet/intel/igb/e1000_i210.c
@@ -44,10 +44,42 @@
 static s32 igb_get_hw_semaphore_i210(struct e1000_hw *hw)
 {
         u32 swsm;
-        s32 ret_val = E1000_SUCCESS;
         s32 timeout = hw->nvm.word_size + 1;
         s32 i = 0;
 
+        /* Get the SW semaphore */
+        while (i < timeout) {
+                swsm = rd32(E1000_SWSM);
+                if (!(swsm & E1000_SWSM_SMBI))
+                        break;
+
+                udelay(50);
+                i++;
+        }
+
+        if (i == timeout) {
+                /* In rare circumstances, the SW semaphore may already be held
+                 * unintentionally. Clear the semaphore once before giving up.
+                 */
+                if (hw->dev_spec._82575.clear_semaphore_once) {
+                        hw->dev_spec._82575.clear_semaphore_once = false;
+                        igb_put_hw_semaphore(hw);
+                        for (i = 0; i < timeout; i++) {
+                                swsm = rd32(E1000_SWSM);
+                                if (!(swsm & E1000_SWSM_SMBI))
+                                        break;
+
+                                udelay(50);
+                        }
+                }
+
+                /* If we do not have the semaphore here, we have to give up. */
+                if (i == timeout) {
+                        hw_dbg("Driver can't access device - SMBI bit is set.\n");
+                        return -E1000_ERR_NVM;
+                }
+        }
+
         /* Get the FW semaphore. */
         for (i = 0; i < timeout; i++) {
                 swsm = rd32(E1000_SWSM);
@@ -64,12 +96,10 @@ static s32 igb_get_hw_semaphore_i210(struct e1000_hw *hw)
                 /* Release semaphores */
                 igb_put_hw_semaphore(hw);
                 hw_dbg("Driver can't access the NVM\n");
-                ret_val = -E1000_ERR_NVM;
-                goto out;
+                return -E1000_ERR_NVM;
         }
 
-out:
-        return ret_val;
+        return E1000_SUCCESS;
 }
 
 /**
@@ -99,23 +129,6 @@ void igb_release_nvm_i210(struct e1000_hw *hw)
 }
 
 /**
- *  igb_put_hw_semaphore_i210 - Release hardware semaphore
- *  @hw: pointer to the HW structure
- *
- *  Release hardware semaphore used to access the PHY or NVM
- **/
-static void igb_put_hw_semaphore_i210(struct e1000_hw *hw)
-{
-        u32 swsm;
-
-        swsm = rd32(E1000_SWSM);
-
-        swsm &= ~E1000_SWSM_SWESMBI;
-
-        wr32(E1000_SWSM, swsm);
-}
-
-/**
  *  igb_acquire_swfw_sync_i210 - Acquire SW/FW semaphore
  *  @hw: pointer to the HW structure
  *  @mask: specifies which semaphore to acquire
@@ -138,11 +151,11 @@ s32 igb_acquire_swfw_sync_i210(struct e1000_hw *hw, u16 mask)
                 }
 
                 swfw_sync = rd32(E1000_SW_FW_SYNC);
-                if (!(swfw_sync & fwmask))
+                if (!(swfw_sync & (fwmask | swmask)))
                         break;
 
                 /* Firmware currently using resource (fwmask) */
-                igb_put_hw_semaphore_i210(hw);
+                igb_put_hw_semaphore(hw);
                 mdelay(5);
                 i++;
         }
@@ -156,7 +169,7 @@ s32 igb_acquire_swfw_sync_i210(struct e1000_hw *hw, u16 mask)
         swfw_sync |= swmask;
         wr32(E1000_SW_FW_SYNC, swfw_sync);
 
-        igb_put_hw_semaphore_i210(hw);
+        igb_put_hw_semaphore(hw);
 out:
         return ret_val;
 }
@@ -180,7 +193,7 @@ void igb_release_swfw_sync_i210(struct e1000_hw *hw, u16 mask)
         swfw_sync &= ~mask;
         wr32(E1000_SW_FW_SYNC, swfw_sync);
 
-        igb_put_hw_semaphore_i210(hw);
+        igb_put_hw_semaphore(hw);
 }
 
 /**