[PATCH v2 1/2] e1000e: disregard NVM checksum on tgp when valid checksum mask is not set

[Jacek Kowalski]

As described by Vitaly Lifshits:

> Starting from Tiger Lake, LAN NVM is locked for writes by SW, so the
> driver cannot perform checksum validation and correction. This means
> that all NVM images must leave the factory with correct checksum and
> checksum valid bit set. Since Tiger Lake devices were the first to have
> this lock, some systems in the field did not meet this requirement.
> Therefore, for these transitional devices we skip checksum update and
> verification, if the valid bit is not set.

Signed-off-by: Jacek Kowalski <Jacek@xxxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Reviewed-by: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
Fixes: 4051f68318ca9 ("e1000e: Do not take care about recovery NVM checksum")
Cc: stable@xxxxxxxxxxxxxxx
---
v1 -> v2: updated patch description
 drivers/net/ethernet/intel/e1000e/ich8lan.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c
index 364378133526..df4e7d781cb1 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
@@ -4274,6 +4274,8 @@ static s32 e1000_validate_nvm_checksum_ich8lan(struct e1000_hw *hw)
 			ret_val = e1000e_update_nvm_checksum(hw);
 			if (ret_val)
 				return ret_val;
+		} else if (hw->mac.type == e1000_pch_tgp) {
+			return 0;
 		}
 	}
 
-- 
2.47.2