i40e: ShadowRAM checksum calculation change

Due to changes in FW the SW is required to perform double SR dump in
some cases.

Implementation adds two new steps to update nvm checksum function:
* recalculate checksum and check if checksum in NVM is correct
* if checksum in NVM is not correct then update it again

Signed-off-by: Maciej Paczkowski <maciej.paczkowski@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_nvm.c b/drivers/net/ethernet/intel/i40e/i40e_nvm.c
index 0299e5bbb9022a457fa398ca7a401bc73bc6c1b8..ee89779a9a6f09d3234d3e4bc9e9d8704e413b46 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_nvm.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_nvm.c
@@ -574,13 +574,34 @@ i40e_calc_nvm_checksum_exit:
 i40e_status i40e_update_nvm_checksum(struct i40e_hw *hw)
 {
        i40e_status ret_code;
-       u16 checksum;
+       u16 checksum, checksum_sr;
        __le16 le_sum;
 
        ret_code = i40e_calc_nvm_checksum(hw, &checksum);
-       if (!ret_code) {
-               le_sum = cpu_to_le16(checksum);
-               ret_code = i40e_write_nvm_aq(hw, 0x00, I40E_SR_SW_CHECKSUM_WORD,
+       if (ret_code)
+               return ret_code;
+
+       le_sum = cpu_to_le16(checksum);
+       ret_code = i40e_write_nvm_aq(hw, 0x00, I40E_SR_SW_CHECKSUM_WORD,
+                                    1, &le_sum, true);
+       if (ret_code)
+               return ret_code;
+
+       /* Due to changes in FW the SW is required to perform double SR-dump
+        * in some cases. SR-dump is the process when internal shadow RAM is
+        * dumped into flash bank. It is triggered by setting "last_command"
+        * argument in i40e_write_nvm_aq function call.
+        * Since FW 1.8 we need to calculate SR checksum again and update it
+        * in flash if it is not equal to previously computed checksum.
+        * This situation would occur only in FW >= 1.8
+        */
+       ret_code = i40e_calc_nvm_checksum(hw, &checksum_sr);
+       if (ret_code)
+               return ret_code;
+       if (checksum_sr != checksum) {
+               le_sum = cpu_to_le16(checksum_sr);
+               ret_code = i40e_write_nvm_aq(hw, 0x00,
+                                            I40E_SR_SW_CHECKSUM_WORD,
                                             1, &le_sum, true);
        }