e1000e: don't check for alternate MAC addr on parts that don't support it

From: Bruce Allan <bruce.w.allan@intel.com>

The alternate MAC address feature is only supported by 80003ES2LAN and
82571 LOMs as well as a couple 82571 mezzanine cards.  Checking for an
alternate MAC address on other parts can fail leading to the driver not
able to load.  This patch limits the check for an alternate MAC address
to be done only for parts that support the feature.

This issue has been around since support for the feature was introduced
to the e1000e driver in 2.6.34.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Reported-by: Fabio Varesano <fax8@users.sourceforge.net>
Cc: stable@kernel.org
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/e1000e/82571.c

@@ -936,12 +936,14 @@ static s32 e1000_reset_hw_82571(struct e1000_hw *hw)
 	ew32(IMC, 0xffffffff);
 	icr = er32(ICR);
 
-	/* Install any alternate MAC address into RAR0 */
-	ret_val = e1000_check_alt_mac_addr_generic(hw);
-	if (ret_val)
-		return ret_val;
+	if (hw->mac.type == e1000_82571) {
+		/* Install any alternate MAC address into RAR0 */
+		ret_val = e1000_check_alt_mac_addr_generic(hw);
+		if (ret_val)
+			return ret_val;
 
-	e1000e_set_laa_state_82571(hw, true);
+		e1000e_set_laa_state_82571(hw, true);
+	}
 
 	/* Reinitialize the 82571 serdes link state machine */
 	if (hw->phy.media_type == e1000_media_type_internal_serdes)
@@ -1618,14 +1620,16 @@ static s32 e1000_read_mac_addr_82571(struct e1000_hw *hw)
 {
 	s32 ret_val = 0;
 
-	/*
-	 * If there's an alternate MAC address place it in RAR0
-	 * so that it will override the Si installed default perm
-	 * address.
-	 */
-	ret_val = e1000_check_alt_mac_addr_generic(hw);
-	if (ret_val)
-		goto out;
+	if (hw->mac.type == e1000_82571) {
+		/*
+		 * If there's an alternate MAC address place it in RAR0
+		 * so that it will override the Si installed default perm
+		 * address.
+		 */
+		ret_val = e1000_check_alt_mac_addr_generic(hw);
+		if (ret_val)
+			goto out;
+	}
 
 	ret_val = e1000_read_mac_addr_generic(hw);
 

drivers/net/e1000e/defines.h

@@ -621,6 +621,7 @@
 #define E1000_FLASH_UPDATES  2000
 
 /* NVM Word Offsets */
+#define NVM_COMPAT                 0x0003
 #define NVM_ID_LED_SETTINGS        0x0004
 #define NVM_INIT_CONTROL2_REG      0x000F
 #define NVM_INIT_CONTROL3_PORT_B   0x0014
@@ -643,6 +644,9 @@
 /* Mask bits for fields in Word 0x1a of the NVM */
 #define NVM_WORD1A_ASPM_MASK  0x000C
 
+/* Mask bits for fields in Word 0x03 of the EEPROM */
+#define NVM_COMPAT_LOM    0x0800
+
 /* For checksumming, the sum of all words in the NVM should equal 0xBABA. */
 #define NVM_SUM                    0xBABA
 

drivers/net/e1000e/lib.c

@@ -183,6 +183,16 @@ s32 e1000_check_alt_mac_addr_generic(struct e1000_hw *hw)
 	u16 offset, nvm_alt_mac_addr_offset, nvm_data;
 	u8 alt_mac_addr[ETH_ALEN];
 
+	ret_val = e1000_read_nvm(hw, NVM_COMPAT, 1, &nvm_data);
+	if (ret_val)
+		goto out;
+
+	/* Check for LOM (vs. NIC) or one of two valid mezzanine cards */
+	if (!((nvm_data & NVM_COMPAT_LOM) ||
+	      (hw->adapter->pdev->device == E1000_DEV_ID_82571EB_SERDES_DUAL) ||
+	      (hw->adapter->pdev->device == E1000_DEV_ID_82571EB_SERDES_QUAD)))
+		goto out;
+
 	ret_val = e1000_read_nvm(hw, NVM_ALT_MAC_ADDR_PTR, 1,
 	                         &nvm_alt_mac_addr_offset);
 	if (ret_val) {