e1000e: prevent NVM corruption on sectors larger than 4K

Limit NVM writes to 4K sections to prevent NVM corruption on larger
sector allocations (up to 64K).

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 2 deletions

diff --git a/drivers/net/e1000e/ich8lan.c b/drivers/net/e1000e/ich8lan.c
index bf9b97db76b9..0e0755f0db3f 100644
--- a/drivers/net/e1000e/ich8lan.c
+++ b/drivers/net/e1000e/ich8lan.c
@@ -338,6 +338,7 @@ static s32 e1000_init_nvm_params_ich8lan(struct e1000_hw *hw)
 {
         struct e1000_nvm_info *nvm = &hw->nvm;
         struct e1000_dev_spec_ich8lan *dev_spec = &hw->dev_spec.ich8lan;
+        union ich8_hws_flash_status hsfsts;
         u32 gfpreg;
         u32 sector_base_addr;
         u32 sector_end_addr;
@@ -374,6 +375,20 @@ static s32 e1000_init_nvm_params_ich8lan(struct e1000_hw *hw)
         /* Adjust to word count */
         nvm->flash_bank_size /= sizeof(u16);
 
+        /*
+         * Make sure the flash bank size does not overwrite the 4k
+         * sector ranges. We may have 64k allotted to us but we only care
+         * about the first 2 4k sectors. Therefore, if we have anything less
+         * than 64k set in the HSFSTS register, we will reduce the bank size
+         * down to 4k and let the rest remain unused. If berasesz == 3, then
+         * we are working in 64k mode. Otherwise we are not.
+         */
+        if (nvm->flash_bank_size > E1000_ICH8_SHADOW_RAM_WORDS) {
+                hsfsts.regval = er16flash(ICH_FLASH_HSFSTS);
+                if (hsfsts.hsf_status.berasesz != 3)
+                        nvm->flash_bank_size = E1000_ICH8_SHADOW_RAM_WORDS;
+        }
+
         nvm->word_size = E1000_ICH8_SHADOW_RAM_WORDS;
 
         /* Clear shadow ram */
@@ -1932,7 +1947,7 @@ static s32 e1000_erase_flash_bank_ich8lan(struct e1000_hw *hw, u32 bank)
                 break;
         case 1:
                 sector_size = ICH_FLASH_SEG_SIZE_4K;
-                iteration = flash_bank_size / ICH_FLASH_SEG_SIZE_4K;
+                iteration = 1;
                 break;
         case 2:
                 if (hw->mac.type == e1000_ich9lan) {
@@ -1944,7 +1959,7 @@ static s32 e1000_erase_flash_bank_ich8lan(struct e1000_hw *hw, u32 bank)
                 break;
         case 3:
                 sector_size = ICH_FLASH_SEG_SIZE_64K;
-                iteration = flash_bank_size / ICH_FLASH_SEG_SIZE_64K;
+                iteration = 1;
                 break;
         default:
                 return -E1000_ERR_NVM;