ixgbe: improve EEPROM read/write operations

Introduce buffered read/writes which greatly improves performance on
parts with large EEPROMs.

Previously reading/writing a word requires taking/releasing of synchronization
semaphores which adds 10ms to each operation. The optimization is to
read/write in buffers, but make sure the semaphore is not held for >500ms
according to the datasheet.

Since we can't read the EEPROM page size ixgbe_detect_eeprom_page_size() is
used to discover the EEPROM size when needed and keeps the result in
word_page_size for the rest of the run time.

Use buffered reads for ethtool -e.
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Evan Swanson <evan.swanson@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ixgbe/ixgbe_82598.c

@@ -1281,6 +1281,7 @@ static struct ixgbe_mac_operations mac_ops_82598 = {
 static struct ixgbe_eeprom_operations eeprom_ops_82598 = {
 	.init_params		= &ixgbe_init_eeprom_params_generic,
 	.read			= &ixgbe_read_eerd_generic,
+	.read_buffer		= &ixgbe_read_eerd_buffer_generic,
 	.calc_checksum          = &ixgbe_calc_eeprom_checksum_generic,
 	.validate_checksum	= &ixgbe_validate_eeprom_checksum_generic,
 	.update_checksum	= &ixgbe_update_eeprom_checksum_generic,

drivers/net/ixgbe/ixgbe_82599.c

@@ -2063,6 +2063,39 @@ static bool ixgbe_verify_lesm_fw_enabled_82599(struct ixgbe_hw *hw)
 	return lesm_enabled;
 }
 
+/**
+ *  ixgbe_read_eeprom_buffer_82599 - Read EEPROM word(s) using
+ *  fastest available method
+ *
+ *  @hw: pointer to hardware structure
+ *  @offset: offset of  word in EEPROM to read
+ *  @words: number of words
+ *  @data: word(s) read from the EEPROM
+ *
+ *  Retrieves 16 bit word(s) read from EEPROM
+ **/
+static s32 ixgbe_read_eeprom_buffer_82599(struct ixgbe_hw *hw, u16 offset,
+					  u16 words, u16 *data)
+{
+	struct ixgbe_eeprom_info *eeprom = &hw->eeprom;
+	s32 ret_val = IXGBE_ERR_CONFIG;
+
+	/*
+	 * If EEPROM is detected and can be addressed using 14 bits,
+	 * use EERD otherwise use bit bang
+	 */
+	if ((eeprom->type == ixgbe_eeprom_spi) &&
+	    (offset + (words - 1) <= IXGBE_EERD_MAX_ADDR))
+		ret_val = ixgbe_read_eerd_buffer_generic(hw, offset, words,
+							 data);
+	else
+		ret_val = ixgbe_read_eeprom_buffer_bit_bang_generic(hw, offset,
+								    words,
+								    data);
+
+	return ret_val;
+}
+
 /**
  *  ixgbe_read_eeprom_82599 - Read EEPROM word using
  *  fastest available method
@@ -2139,7 +2172,9 @@ static struct ixgbe_mac_operations mac_ops_82599 = {
 static struct ixgbe_eeprom_operations eeprom_ops_82599 = {
 	.init_params		= &ixgbe_init_eeprom_params_generic,
 	.read			= &ixgbe_read_eeprom_82599,
+	.read_buffer		= &ixgbe_read_eeprom_buffer_82599,
 	.write			= &ixgbe_write_eeprom_generic,
+	.write_buffer		= &ixgbe_write_eeprom_buffer_bit_bang_generic,
 	.calc_checksum		= &ixgbe_calc_eeprom_checksum_generic,
 	.validate_checksum	= &ixgbe_validate_eeprom_checksum_generic,
 	.update_checksum	= &ixgbe_update_eeprom_checksum_generic,

drivers/net/ixgbe/ixgbe_common.h

@@ -49,10 +49,18 @@ s32 ixgbe_led_off_generic(struct ixgbe_hw *hw, u32 index);
 
 s32 ixgbe_init_eeprom_params_generic(struct ixgbe_hw *hw);
 s32 ixgbe_write_eeprom_generic(struct ixgbe_hw *hw, u16 offset, u16 data);
+s32 ixgbe_write_eeprom_buffer_bit_bang_generic(struct ixgbe_hw *hw, u16 offset,
+					       u16 words, u16 *data);
 s32 ixgbe_read_eerd_generic(struct ixgbe_hw *hw, u16 offset, u16 *data);
+s32 ixgbe_read_eerd_buffer_generic(struct ixgbe_hw *hw, u16 offset,
+				   u16 words, u16 *data);
 s32 ixgbe_write_eewr_generic(struct ixgbe_hw *hw, u16 offset, u16 data);
+s32 ixgbe_write_eewr_buffer_generic(struct ixgbe_hw *hw, u16 offset,
+				    u16 words, u16 *data);
 s32 ixgbe_read_eeprom_bit_bang_generic(struct ixgbe_hw *hw, u16 offset,
                                        u16 *data);
+s32 ixgbe_read_eeprom_buffer_bit_bang_generic(struct ixgbe_hw *hw, u16 offset,
+					      u16 words, u16 *data);
 u16 ixgbe_calc_eeprom_checksum_generic(struct ixgbe_hw *hw);
 s32 ixgbe_validate_eeprom_checksum_generic(struct ixgbe_hw *hw,
                                            u16 *checksum_val);

drivers/net/ixgbe/ixgbe_ethtool.c

@@ -847,11 +847,8 @@ static int ixgbe_get_eeprom(struct net_device *netdev,
 	if (!eeprom_buff)
 		return -ENOMEM;
 
-	for (i = 0; i < eeprom_len; i++) {
-		if ((ret_val = hw->eeprom.ops.read(hw, first_word + i,
-		    &eeprom_buff[i])))
-			break;
-	}
+	ret_val = hw->eeprom.ops.read_buffer(hw, first_word, eeprom_len,
+					     eeprom_buff);
 
 	/* Device's eeprom is always little-endian, word addressable */
 	for (i = 0; i < eeprom_len; i++)

drivers/net/ixgbe/ixgbe_type.h

@@ -1668,6 +1668,10 @@
 
 #define IXGBE_ETH_LENGTH_OF_ADDRESS   6
 
+#define IXGBE_EEPROM_PAGE_SIZE_MAX       128
+#define IXGBE_EEPROM_RD_BUFFER_MAX_COUNT 512 /* EEPROM words # read in burst */
+#define IXGBE_EEPROM_WR_BUFFER_MAX_COUNT 256 /* EEPROM words # wr in burst */
+
 #ifndef IXGBE_EEPROM_GRANT_ATTEMPTS
 #define IXGBE_EEPROM_GRANT_ATTEMPTS 1000 /* EEPROM # attempts to gain grant */
 #endif
@@ -2563,7 +2567,9 @@ typedef u8* (*ixgbe_mc_addr_itr) (struct ixgbe_hw *hw, u8 **mc_addr_ptr,
 struct ixgbe_eeprom_operations {
 	s32 (*init_params)(struct ixgbe_hw *);
 	s32 (*read)(struct ixgbe_hw *, u16, u16 *);
+	s32 (*read_buffer)(struct ixgbe_hw *, u16, u16, u16 *);
 	s32 (*write)(struct ixgbe_hw *, u16, u16);
+	s32 (*write_buffer)(struct ixgbe_hw *, u16, u16, u16 *);
 	s32 (*validate_checksum)(struct ixgbe_hw *, u16 *);
 	s32 (*update_checksum)(struct ixgbe_hw *);
 	u16 (*calc_checksum)(struct ixgbe_hw *);
@@ -2649,6 +2655,7 @@ struct ixgbe_eeprom_info {
 	u32                             semaphore_delay;
 	u16                             word_size;
 	u16                             address_bits;
+	u16                             word_page_size;
 };
 
 #define IXGBE_FLAGS_DOUBLE_RESET_REQUIRED	0x01

drivers/net/ixgbe/ixgbe_x540.c

@@ -304,16 +304,19 @@ static s32 ixgbe_init_eeprom_params_X540(struct ixgbe_hw *hw)
 }
 
 /**
- * ixgbe_read_eerd_X540 - Read EEPROM word using EERD
- * @hw: pointer to hardware structure
- * @offset: offset of word in the EEPROM to read
- * @data: word read from the EERPOM
+ *  ixgbe_read_eerd_X540- Read EEPROM word using EERD
+ *  @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 EERD register.
  **/
 static s32 ixgbe_read_eerd_X540(struct ixgbe_hw *hw, u16 offset, u16 *data)
 {
-	s32 status;
+	s32 status = 0;
 
-	if (hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_EEP_SM) == 0)
+	if (hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_EEP_SM) ==
+	    0)
 		status = ixgbe_read_eerd_generic(hw, offset, data);
 	else
 		status = IXGBE_ERR_SWFW_SYNC;
@@ -322,6 +325,31 @@ static s32 ixgbe_read_eerd_X540(struct ixgbe_hw *hw, u16 offset, u16 *data)
 	return status;
 }
 
+/**
+ *  ixgbe_read_eerd_buffer_X540 - Read EEPROM word(s) using EERD
+ *  @hw: pointer to hardware structure
+ *  @offset: offset of  word in the EEPROM to read
+ *  @words: number of words
+ *  @data: word(s) read from the EEPROM
+ *
+ *  Reads a 16 bit word(s) from the EEPROM using the EERD register.
+ **/
+static s32 ixgbe_read_eerd_buffer_X540(struct ixgbe_hw *hw,
+				       u16 offset, u16 words, u16 *data)
+{
+	s32 status = 0;
+
+	if (hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_EEP_SM) ==
+	    0)
+		status = ixgbe_read_eerd_buffer_generic(hw, offset,
+							words, data);
+	else
+		status = IXGBE_ERR_SWFW_SYNC;
+
+	hw->mac.ops.release_swfw_sync(hw, IXGBE_GSSR_EEP_SM);
+	return status;
+}
+
 /**
  *  ixgbe_write_eewr_X540 - Write EEPROM word using EEWR
  *  @hw: pointer to hardware structure
@@ -343,6 +371,31 @@ static s32 ixgbe_write_eewr_X540(struct ixgbe_hw *hw, u16 offset, u16 data)
 	return status;
 }
 
+/**
+ *  ixgbe_write_eewr_buffer_X540 - Write EEPROM word(s) using EEWR
+ *  @hw: pointer to hardware structure
+ *  @offset: offset of  word in the EEPROM to write
+ *  @words: number of words
+ *  @data: word(s) write to the EEPROM
+ *
+ *  Write a 16 bit word(s) to the EEPROM using the EEWR register.
+ **/
+static s32 ixgbe_write_eewr_buffer_X540(struct ixgbe_hw *hw,
+					u16 offset, u16 words, u16 *data)
+{
+	s32 status = 0;
+
+	if (hw->mac.ops.acquire_swfw_sync(hw, IXGBE_GSSR_EEP_SM) ==
+	    0)
+		status = ixgbe_write_eewr_buffer_generic(hw, offset,
+							 words, data);
+	else
+		status = IXGBE_ERR_SWFW_SYNC;
+
+	hw->mac.ops.release_swfw_sync(hw, IXGBE_GSSR_EEP_SM);
+	return status;
+}
+
 /**
  *  ixgbe_calc_eeprom_checksum_X540 - Calculates and returns the checksum
  *
@@ -851,7 +904,9 @@ static struct ixgbe_mac_operations mac_ops_X540 = {
 static struct ixgbe_eeprom_operations eeprom_ops_X540 = {
 	.init_params            = &ixgbe_init_eeprom_params_X540,
 	.read                   = &ixgbe_read_eerd_X540,
+	.read_buffer		= &ixgbe_read_eerd_buffer_X540,
 	.write                  = &ixgbe_write_eewr_X540,
+	.write_buffer		= &ixgbe_write_eewr_buffer_X540,
 	.calc_checksum		= &ixgbe_calc_eeprom_checksum_X540,
 	.validate_checksum      = &ixgbe_validate_eeprom_checksum_X540,
 	.update_checksum        = &ixgbe_update_eeprom_checksum_X540,