ixgbe: Fix issues with EEPROM access

There are two problems with EEPROM access. One is that it needs to
hold the semaphore until the entire response is read or else the
response can be corrupted by other firmware accesses. The second
problem is that acquiring and releasing the semaphore is slow, so
it should be taken and released once when multiple EEPROM accesses
will be done.

Both of these issues can be solved by adding a new function,
ixgbe_hic_unlocked, to issue firmware commands that will assume
that the caller has acquired the needed semaphore.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_common.c

@@ -3593,43 +3593,29 @@ u8 ixgbe_calculate_checksum(u8 *buffer, u32 length)
 }
 
 /**
- *  ixgbe_host_interface_command - Issue command to manageability block
+ *  ixgbe_hic_unlocked - Issue command to manageability block unlocked
  *  @hw: pointer to the HW structure
- *  @buffer: contains the command to write and where the return status will
- *           be placed
+ *  @buffer: command to write and where the return status will be placed
  *  @length: length of buffer, must be multiple of 4 bytes
  *  @timeout: time in ms to wait for command completion
- *  @return_data: read and return data from the buffer (true) or not (false)
- *  Needed because FW structures are big endian and decoding of
- *  these fields can be 8 bit or 16 bit based on command. Decoding
- *  is not easily understood without making a table of commands.
- *  So we will leave this up to the caller to read back the data
- *  in these cases.
  *
- *  Communicates with the manageability block.  On success return 0
- *  else return IXGBE_ERR_HOST_INTERFACE_COMMAND.
+ *  Communicates with the manageability block. On success return 0
+ *  else returns semaphore error when encountering an error acquiring
+ *  semaphore or IXGBE_ERR_HOST_INTERFACE_COMMAND when command fails.
+ *
+ *  This function assumes that the IXGBE_GSSR_SW_MNG_SM semaphore is held
+ *  by the caller.
  **/
-s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, void *buffer,
-				 u32 length, u32 timeout,
-				 bool return_data)
+s32 ixgbe_hic_unlocked(struct ixgbe_hw *hw, u32 *buffer, u32 length,
+		       u32 timeout)
 {
-	u32 hdr_size = sizeof(struct ixgbe_hic_hdr);
-	u32 hicr, i, bi, fwsts;
-	u16 buf_len, dword_len;
-	union {
-		struct ixgbe_hic_hdr hdr;
-		u32 u32arr[1];
-	} *bp = buffer;
-	s32 status;
+	u32 hicr, i, fwsts;
+	u16 dword_len;
 
 	if (!length || length > IXGBE_HI_MAX_BLOCK_BYTE_LENGTH) {
 		hw_dbg(hw, "Buffer length failure buffersize-%d.\n", length);
 		return IXGBE_ERR_HOST_INTERFACE_COMMAND;
 	}
-	/* Take management host interface semaphore */
-	status = hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_SW_MNG_SM);
-	if (status)
-		return status;
 
 	/* Set bit 9 of FWSTS clearing FW reset indication */
 	fwsts = IXGBE_READ_REG(hw, IXGBE_FWSTS);
@@ -3639,15 +3625,13 @@ s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, void *buffer,
 	hicr = IXGBE_READ_REG(hw, IXGBE_HICR);
 	if (!(hicr & IXGBE_HICR_EN)) {
 		hw_dbg(hw, "IXGBE_HOST_EN bit disabled.\n");
-		status = IXGBE_ERR_HOST_INTERFACE_COMMAND;
-		goto rel_out;
+		return IXGBE_ERR_HOST_INTERFACE_COMMAND;
 	}
 
 	/* Calculate length in DWORDs. We must be DWORD aligned */
 	if (length % sizeof(u32)) {
 		hw_dbg(hw, "Buffer length failure, not aligned to dword");
-		status = IXGBE_ERR_INVALID_ARGUMENT;
-		goto rel_out;
+		return IXGBE_ERR_INVALID_ARGUMENT;
 	}
 
 	dword_len = length >> 2;
@@ -3657,7 +3641,7 @@ s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, void *buffer,
 	 */
 	for (i = 0; i < dword_len; i++)
 		IXGBE_WRITE_REG_ARRAY(hw, IXGBE_FLEX_MNG,
-				      i, cpu_to_le32(bp->u32arr[i]));
+				      i, cpu_to_le32(buffer[i]));
 
 	/* Setting this bit tells the ARC that a new command is pending. */
 	IXGBE_WRITE_REG(hw, IXGBE_HICR, hicr | IXGBE_HICR_C);
@@ -3671,11 +3655,54 @@ s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, void *buffer,
 
 	/* Check command successful completion. */
 	if ((timeout && i == timeout) ||
-	    !(IXGBE_READ_REG(hw, IXGBE_HICR) & IXGBE_HICR_SV)) {
-		hw_dbg(hw, "Command has failed with no status valid.\n");
-		status = IXGBE_ERR_HOST_INTERFACE_COMMAND;
-		goto rel_out;
+	    !(IXGBE_READ_REG(hw, IXGBE_HICR) & IXGBE_HICR_SV))
+		return IXGBE_ERR_HOST_INTERFACE_COMMAND;
+
+	return 0;
+}
+
+/**
+ *  ixgbe_host_interface_command - Issue command to manageability block
+ *  @hw: pointer to the HW structure
+ *  @buffer: contains the command to write and where the return status will
+ *           be placed
+ *  @length: length of buffer, must be multiple of 4 bytes
+ *  @timeout: time in ms to wait for command completion
+ *  @return_data: read and return data from the buffer (true) or not (false)
+ *  Needed because FW structures are big endian and decoding of
+ *  these fields can be 8 bit or 16 bit based on command. Decoding
+ *  is not easily understood without making a table of commands.
+ *  So we will leave this up to the caller to read back the data
+ *  in these cases.
+ *
+ *  Communicates with the manageability block.  On success return 0
+ *  else return IXGBE_ERR_HOST_INTERFACE_COMMAND.
+ **/
+s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, void *buffer,
+				 u32 length, u32 timeout,
+				 bool return_data)
+{
+	u32 hdr_size = sizeof(struct ixgbe_hic_hdr);
+	union {
+		struct ixgbe_hic_hdr hdr;
+		u32 u32arr[1];
+	} *bp = buffer;
+	u16 buf_len, dword_len;
+	s32 status;
+	u32 bi;
+
+	if (!length || length > IXGBE_HI_MAX_BLOCK_BYTE_LENGTH) {
+		hw_dbg(hw, "Buffer length failure buffersize-%d.\n", length);
+		return IXGBE_ERR_HOST_INTERFACE_COMMAND;
 	}
+	/* Take management host interface semaphore */
+	status = hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_SW_MNG_SM);
+	if (status)
+		return status;
+
+	status = ixgbe_hic_unlocked(hw, buffer, length, timeout);
+	if (status)
+		goto rel_out;
 
 	if (!return_data)
 		goto rel_out;

drivers/net/ethernet/intel/ixgbe/ixgbe_common.h

@@ -115,6 +115,7 @@ s32 ixgbe_set_fw_drv_ver_generic(struct ixgbe_hw *hw, u8 maj, u8 min,
 u8 ixgbe_calculate_checksum(u8 *buffer, u32 length);
 s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, void *, u32 length,
 				 u32 timeout, bool return_data);
+s32 ixgbe_hic_unlocked(struct ixgbe_hw *hw, u32 *buffer, u32 len, u32 timeout);
 void ixgbe_clear_tx_pending(struct ixgbe_hw *hw);
 bool ixgbe_mng_present(struct ixgbe_hw *hw);
 bool ixgbe_mng_enabled(struct ixgbe_hw *hw);

drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c

@@ -624,41 +624,6 @@ static s32 ixgbe_read_iosf_sb_reg_x550a(struct ixgbe_hw *hw, u32 reg_addr,
 	return status;
 }
 
-/** ixgbe_read_ee_hostif_data_X550 - Read EEPROM word using a host interface
- *  command assuming that the semaphore is already obtained.
- *  @hw: pointer to hardware structure
- *  @offset: offset of  word in the EEPROM to read
- *  @data: word read from the EEPROM
- *
- *  Reads a 16 bit word from the EEPROM using the hostif.
- **/
-static s32 ixgbe_read_ee_hostif_data_X550(struct ixgbe_hw *hw, u16 offset,
-					  u16 *data)
-{
-	s32 status;
-	struct ixgbe_hic_read_shadow_ram buffer;
-
-	buffer.hdr.req.cmd = FW_READ_SHADOW_RAM_CMD;
-	buffer.hdr.req.buf_lenh = 0;
-	buffer.hdr.req.buf_lenl = FW_READ_SHADOW_RAM_LEN;
-	buffer.hdr.req.checksum = FW_DEFAULT_CHECKSUM;
-
-	/* convert offset from words to bytes */
-	buffer.address = cpu_to_be32(offset * 2);
-	/* one word */
-	buffer.length = cpu_to_be16(sizeof(u16));
-
-	status = ixgbe_host_interface_command(hw, &buffer, sizeof(buffer),
-					      IXGBE_HI_COMMAND_TIMEOUT, false);
-	if (status)
-		return status;
-
-	*data = (u16)IXGBE_READ_REG_ARRAY(hw, IXGBE_FLEX_MNG,
-					  FW_NVM_DATA_OFFSET);
-
-	return 0;
-}
-
 /** ixgbe_read_ee_hostif_buffer_X550- Read EEPROM word(s) using hostif
  *  @hw: pointer to hardware structure
  *  @offset: offset of  word in the EEPROM to read
@@ -670,6 +635,7 @@ static s32 ixgbe_read_ee_hostif_data_X550(struct ixgbe_hw *hw, u16 offset,
 static s32 ixgbe_read_ee_hostif_buffer_X550(struct ixgbe_hw *hw,
 					    u16 offset, u16 words, u16 *data)
 {
+	const u32 mask = IXGBE_GSSR_SW_MNG_SM | IXGBE_GSSR_EEP_SM;
 	struct ixgbe_hic_read_shadow_ram buffer;
 	u32 current_word = 0;
 	u16 words_to_read;
@@ -677,7 +643,7 @@ static s32 ixgbe_read_ee_hostif_buffer_X550(struct ixgbe_hw *hw,
 	u32 i;
 
 	/* Take semaphore for the entire operation. */
-	status = hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_EEP_SM);
+	status = hw->mac.ops.acquire_swfw_sync(hw, mask);
 	if (status) {
 		hw_dbg(hw, "EEPROM read buffer - semaphore failed\n");
 		return status;
@@ -698,10 +664,8 @@ static s32 ixgbe_read_ee_hostif_buffer_X550(struct ixgbe_hw *hw,
 		buffer.address = cpu_to_be32((offset + current_word) * 2);
 		buffer.length = cpu_to_be16(words_to_read * 2);
 
-		status = ixgbe_host_interface_command(hw, &buffer,
-						      sizeof(buffer),
-						      IXGBE_HI_COMMAND_TIMEOUT,
-						      false);
+		status = ixgbe_hic_unlocked(hw, (u32 *)&buffer, sizeof(buffer),
+					    IXGBE_HI_COMMAND_TIMEOUT);
 		if (status) {
 			hw_dbg(hw, "Host interface command failed\n");
 			goto out;
@@ -725,7 +689,7 @@ static s32 ixgbe_read_ee_hostif_buffer_X550(struct ixgbe_hw *hw,
 	}
 
 out:
-	hw->mac.ops.release_swfw_sync(hw, IXGBE_GSSR_EEP_SM);
+	hw->mac.ops.release_swfw_sync(hw, mask);
 	return status;
 }
 
@@ -896,15 +860,32 @@ static s32 ixgbe_calc_eeprom_checksum_X550(struct ixgbe_hw *hw)
  **/
 static s32 ixgbe_read_ee_hostif_X550(struct ixgbe_hw *hw, u16 offset, u16 *data)
 {
-	s32 status = 0;
+	const u32 mask = IXGBE_GSSR_SW_MNG_SM | IXGBE_GSSR_EEP_SM;
+	struct ixgbe_hic_read_shadow_ram buffer;
+	s32 status;
 
-	if (hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_EEP_SM) == 0) {
-		status = ixgbe_read_ee_hostif_data_X550(hw, offset, data);
-		hw->mac.ops.release_swfw_sync(hw, IXGBE_GSSR_EEP_SM);
-	} else {
-		status = IXGBE_ERR_SWFW_SYNC;
+	buffer.hdr.req.cmd = FW_READ_SHADOW_RAM_CMD;
+	buffer.hdr.req.buf_lenh = 0;
+	buffer.hdr.req.buf_lenl = FW_READ_SHADOW_RAM_LEN;
+	buffer.hdr.req.checksum = FW_DEFAULT_CHECKSUM;
+
+	/* convert offset from words to bytes */
+	buffer.address = cpu_to_be32(offset * 2);
+	/* one word */
+	buffer.length = cpu_to_be16(sizeof(u16));
+
+	status = hw->mac.ops.acquire_swfw_sync(hw, mask);
+	if (status)
+		return status;
+
+	status = ixgbe_hic_unlocked(hw, (u32 *)&buffer, sizeof(buffer),
+				    IXGBE_HI_COMMAND_TIMEOUT);
+	if (!status) {
+		*data = (u16)IXGBE_READ_REG_ARRAY(hw, IXGBE_FLEX_MNG,
+						  FW_NVM_DATA_OFFSET);
 	}
 
+	hw->mac.ops.release_swfw_sync(hw, mask);
 	return status;
 }