e1000: Rewrite EEPROM checksum error to give more information

As an aide to debugging, we should print out the expected value of the
EEPROM checksum in addition to just saying that it is wrong.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Cc: Ben Warren <biggerbadderben@gmail.com>

diff --git a/drivers/net/e1000.c b/drivers/net/e1000.c
index c7c745a451e7b11698002c545b12d9e30cc26eb1..39057d231683bb737257dec26dd61a00447dbf79 100644 (file)
--- a/drivers/net/e1000.c
+++ b/drivers/net/e1000.c
@@ -876,29 +876,41 @@ e1000_read_eeprom(struct e1000_hw *hw, uint16_t offset,
  * If the the sum of the 64 16 bit words is 0xBABA, the EEPROM's checksum is
  * valid.
  *****************************************************************************/
-static int
-e1000_validate_eeprom_checksum(struct eth_device *nic)
+static int e1000_validate_eeprom_checksum(struct e1000_hw *hw)
 {
-       struct e1000_hw *hw = nic->priv;
-       uint16_t checksum = 0;
-       uint16_t i, eeprom_data;
+       uint16_t i, checksum, checksum_reg, *buf;
 
        DEBUGFUNC();
 
-       for (i = 0; i < (EEPROM_CHECKSUM_REG + 1); i++) {
-               if (e1000_read_eeprom(hw, i, 1,  &eeprom_data) < 0) {
-                       DEBUGOUT("EEPROM Read Error\n");
-                       return -E1000_ERR_EEPROM;
-               }
-               checksum += eeprom_data;
+       /* Allocate a temporary buffer */
+       buf = malloc(sizeof(buf[0]) * (EEPROM_CHECKSUM_REG + 1));
+       if (!buf) {
+               E1000_ERR(hw->nic, "Unable to allocate EEPROM buffer!\n");
+               return -E1000_ERR_EEPROM;
        }
 
-       if (checksum == (uint16_t) EEPROM_SUM) {
-               return 0;
-       } else {
-               DEBUGOUT("EEPROM Checksum Invalid\n");
+       /* Read the EEPROM */
+       if (e1000_read_eeprom(hw, 0, EEPROM_CHECKSUM_REG + 1, buf) < 0) {
+               E1000_ERR(hw->nic, "Unable to read EEPROM!\n");
                return -E1000_ERR_EEPROM;
        }
+
+       /* Compute the checksum */
+       for (i = 0; i < EEPROM_CHECKSUM_REG; i++)
+               checksum += buf[i];
+       checksum = ((uint16_t)EEPROM_SUM) - checksum;
+       checksum_reg = buf[i];
+
+       /* Verify it! */
+       if (checksum == checksum_reg)
+               return 0;
+
+       /* Hrm, verification failed, print an error */
+       E1000_ERR(hw->nic, "EEPROM checksum is incorrect!\n");
+       E1000_ERR(hw->nic, "  ...register was 0x%04hx, calculated 0x%04hx\n",
+                       checksum_reg, checksum);
+
+       return -E1000_ERR_EEPROM;
 }
 
 /*****************************************************************************
@@ -5243,10 +5255,8 @@ e1000_initialize(bd_t * bis)
                        E1000_ERR(nic, "EEPROM is invalid!\n");
                        continue;
                }
-               if (e1000_validate_eeprom_checksum(nic) < 0) {
-                       E1000_ERR(nic, "EEPROM checksum is bad!\n");
+               if (e1000_validate_eeprom_checksum(hw))
                        continue;
-               }
 #endif
                e1000_read_mac_addr(nic);
                e1000_get_bus_type(hw);