i40e: rework shadow ram read functions

Rework Shadow RAM read word/buffer functions to not use AQ Request
Resource commands.  Requesting resource is not needed for SR read
operations which are done through SRCTL register.  Access to SR through
register is controlled through DONE bit within SRCTL.  With this change
we do not block whole NVM resource for SR read operations.

Change-Id: I73e96cdea39a45ee7b5bdf038e527308de2d9efe
Signed-off-by: Kamil Krawczyk <kamil.krawczyk@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_nvm.c

@@ -166,15 +166,15 @@ static i40e_status i40e_poll_sr_srctl_done_bit(struct i40e_hw *hw)
 }
 
 /**
- *  i40e_read_nvm_srctl - Reads Shadow RAM.
+ *  i40e_read_nvm_word - Reads Shadow RAM
  *  @hw: pointer to the HW structure.
  *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
  *  @data: word read from the Shadow RAM.
  *
  *  Reads 16 bit word from the Shadow RAM using the GLNVM_SRCTL register.
  **/
-static i40e_status i40e_read_nvm_srctl(struct i40e_hw *hw, u16 offset,
-						 u16 *data)
+i40e_status i40e_read_nvm_word(struct i40e_hw *hw, u16 offset,
+					 u16 *data)
 {
 	i40e_status ret_code = I40E_ERR_TIMEOUT;
 	u32 sr_reg;
@@ -210,29 +210,6 @@ read_nvm_exit:
 	return ret_code;
 }
 
-/**
- *  i40e_read_nvm_word - Reads Shadow RAM word.
- *  @hw: pointer to the HW structure.
- *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
- *  @data: word read from the Shadow RAM.
- *
- *  Reads 16 bit word from the Shadow RAM. Each read is preceded
- *  with the NVM ownership taking and followed by the release.
- **/
-i40e_status i40e_read_nvm_word(struct i40e_hw *hw, u16 offset,
-					 u16 *data)
-{
-	i40e_status ret_code = 0;
-
-	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
-	if (!ret_code) {
-		ret_code = i40e_read_nvm_srctl(hw, offset, data);
-		i40e_release_nvm(hw);
-	}
-
-	return ret_code;
-}
-
 /**
  *  i40e_read_nvm_buffer - Reads Shadow RAM buffer.
  *  @hw: pointer to the HW structure.
@@ -250,30 +227,18 @@ i40e_status i40e_read_nvm_buffer(struct i40e_hw *hw, u16 offset,
 {
 	i40e_status ret_code = 0;
 	u16 index, word;
-	u32 time;
 
-	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
-	if (!ret_code) {
-		/* Loop thru the selected region. */
-		for (word = 0; word < *words; word++) {
-			index = offset + word;
-			ret_code = i40e_read_nvm_srctl(hw, index, &data[word]);
-			if (ret_code)
-				break;
-			/* Check if we didn't exceeded the semaphore timeout. */
-			time = rd32(hw, I40E_GLVFGEN_TIMER);
-			if (time >= hw->nvm.hw_semaphore_timeout) {
-				ret_code = I40E_ERR_TIMEOUT;
-				hw_dbg(hw, "NVM read error: timeout.\n");
-				break;
-			}
-		}
-		/* Update the number of words read from the Shadow RAM. */
-		*words = word;
-		/* Release the NVM ownership. */
-		i40e_release_nvm(hw);
+	/* Loop thru the selected region. */
+	for (word = 0; word < *words; word++) {
+		index = offset + word;
+		ret_code = i40e_read_nvm_word(hw, index, &data[word]);
+		if (ret_code)
+			break;
 	}
 
+	/* Update the number of words read from the Shadow RAM. */
+	*words = word;
+
 	return ret_code;
 }
 
@@ -297,14 +262,14 @@ static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
 	u32 i = 0;
 
 	/* read pointer to VPD area */
-	ret_code = i40e_read_nvm_srctl(hw, I40E_SR_VPD_PTR, &vpd_module);
+	ret_code = i40e_read_nvm_word(hw, I40E_SR_VPD_PTR, &vpd_module);
 	if (ret_code) {
 		ret_code = I40E_ERR_NVM_CHECKSUM;
 		goto i40e_calc_nvm_checksum_exit;
 	}
 
 	/* read pointer to PCIe Alt Auto-load module */
-	ret_code = i40e_read_nvm_srctl(hw, I40E_SR_PCIE_ALT_AUTO_LOAD_PTR,
+	ret_code = i40e_read_nvm_word(hw, I40E_SR_PCIE_ALT_AUTO_LOAD_PTR,
 				       &pcie_alt_module);
 	if (ret_code) {
 		ret_code = I40E_ERR_NVM_CHECKSUM;
@@ -331,7 +296,7 @@ static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
 				break;
 		}
 
-		ret_code = i40e_read_nvm_srctl(hw, (u16)i, &word);
+		ret_code = i40e_read_nvm_word(hw, (u16)i, &word);
 		if (ret_code) {
 			ret_code = I40E_ERR_NVM_CHECKSUM;
 			goto i40e_calc_nvm_checksum_exit;
@@ -371,7 +336,7 @@ i40e_status i40e_validate_nvm_checksum(struct i40e_hw *hw,
 	/* Do not use i40e_read_nvm_word() because we do not want to take
 	 * the synchronization semaphores twice here.
 	 */
-	i40e_read_nvm_srctl(hw, I40E_SR_SW_CHECKSUM_WORD, &checksum_sr);
+	i40e_read_nvm_word(hw, I40E_SR_SW_CHECKSUM_WORD, &checksum_sr);
 
 	/* Verify read checksum from EEPROM is the same as
 	 * calculated checksum