path: root/sys/dev/ixl/i40e_nvm.c

/******************************************************************************

  Copyright (c) 2013-2015, Intel Corporation 
  All rights reserved.
  
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  modification, are permitted provided that the following conditions are met:
  
   1. Redistributions of source code must retain the above copyright notice, 
      this list of conditions and the following disclaimer.
  
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      contributors may be used to endorse or promote products derived from 
      this software without specific prior written permission.
  
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  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
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******************************************************************************/
/*$FreeBSD$*/

#include "i40e_prototype.h"

enum i40e_status_code i40e_read_nvm_word_srctl(struct i40e_hw *hw, u16 offset,
					       u16 *data);
enum i40e_status_code i40e_read_nvm_word_aq(struct i40e_hw *hw, u16 offset,
					    u16 *data);
enum i40e_status_code i40e_read_nvm_buffer_srctl(struct i40e_hw *hw, u16 offset,
						 u16 *words, u16 *data);
enum i40e_status_code i40e_read_nvm_buffer_aq(struct i40e_hw *hw, u16 offset,
					      u16 *words, u16 *data);
enum i40e_status_code i40e_read_nvm_aq(struct i40e_hw *hw, u8 module_pointer,
				       u32 offset, u16 words, void *data,
				       bool last_command);

/**
 * i40e_init_nvm_ops - Initialize NVM function pointers
 * @hw: pointer to the HW structure
 *
 * Setup the function pointers and the NVM info structure. Should be called
 * once per NVM initialization, e.g. inside the i40e_init_shared_code().
 * Please notice that the NVM term is used here (& in all methods covered
 * in this file) as an equivalent of the FLASH part mapped into the SR.
 * We are accessing FLASH always thru the Shadow RAM.
 **/
enum i40e_status_code i40e_init_nvm(struct i40e_hw *hw)
{
	struct i40e_nvm_info *nvm = &hw->nvm;
	enum i40e_status_code ret_code = I40E_SUCCESS;
	u32 fla, gens;
	u8 sr_size;

	DEBUGFUNC("i40e_init_nvm");

	/* The SR size is stored regardless of the nvm programming mode
	 * as the blank mode may be used in the factory line.
	 */
	gens = rd32(hw, I40E_GLNVM_GENS);
	sr_size = ((gens & I40E_GLNVM_GENS_SR_SIZE_MASK) >>
			   I40E_GLNVM_GENS_SR_SIZE_SHIFT);
	/* Switching to words (sr_size contains power of 2KB) */
	nvm->sr_size = BIT(sr_size) * I40E_SR_WORDS_IN_1KB;

	/* Check if we are in the normal or blank NVM programming mode */
	fla = rd32(hw, I40E_GLNVM_FLA);
	if (fla & I40E_GLNVM_FLA_LOCKED_MASK) { /* Normal programming mode */
		/* Max NVM timeout */
		nvm->timeout = I40E_MAX_NVM_TIMEOUT;
		nvm->blank_nvm_mode = FALSE;
	} else { /* Blank programming mode */
		nvm->blank_nvm_mode = TRUE;
		ret_code = I40E_ERR_NVM_BLANK_MODE;
		i40e_debug(hw, I40E_DEBUG_NVM, "NVM init error: unsupported blank mode.\n");
	}

	return ret_code;
}

/**
 * i40e_acquire_nvm - Generic request for acquiring the NVM ownership
 * @hw: pointer to the HW structure
 * @access: NVM access type (read or write)
 *
 * This function will request NVM ownership for reading
 * via the proper Admin Command.
 **/
enum i40e_status_code i40e_acquire_nvm(struct i40e_hw *hw,
				       enum i40e_aq_resource_access_type access)
{
	enum i40e_status_code ret_code = I40E_SUCCESS;
	u64 gtime, timeout;
	u64 time_left = 0;

	DEBUGFUNC("i40e_acquire_nvm");

	if (hw->nvm.blank_nvm_mode)
		goto i40e_i40e_acquire_nvm_exit;

	ret_code = i40e_aq_request_resource(hw, I40E_NVM_RESOURCE_ID, access,
					    0, &time_left, NULL);
	/* Reading the Global Device Timer */
	gtime = rd32(hw, I40E_GLVFGEN_TIMER);

	/* Store the timeout */
	hw->nvm.hw_semaphore_timeout = I40E_MS_TO_GTIME(time_left) + gtime;

	if (ret_code)
		i40e_debug(hw, I40E_DEBUG_NVM,
			   "NVM acquire type %d failed time_left=%llu ret=%d aq_err=%d\n",
			   access, time_left, ret_code, hw->aq.asq_last_status);

	if (ret_code && time_left) {
		/* Poll until the current NVM owner timeouts */
		timeout = I40E_MS_TO_GTIME(I40E_MAX_NVM_TIMEOUT) + gtime;
		while ((gtime < timeout) && time_left) {
			i40e_msec_delay(10);
			gtime = rd32(hw, I40E_GLVFGEN_TIMER);
			ret_code = i40e_aq_request_resource(hw,
							I40E_NVM_RESOURCE_ID,
							access, 0, &time_left,
							NULL);
			if (ret_code == I40E_SUCCESS) {
				hw->nvm.hw_semaphore_timeout =
					    I40E_MS_TO_GTIME(time_left) + gtime;
				break;
			}
		}
		if (ret_code != I40E_SUCCESS) {
			hw->nvm.hw_semaphore_timeout = 0;
			i40e_debug(hw, I40E_DEBUG_NVM,
				   "NVM acquire timed out, wait %llu ms before trying again. status=%d aq_err=%d\n",
				   time_left, ret_code, hw->aq.asq_last_status);
		}
	}

i40e_i40e_acquire_nvm_exit:
	return ret_code;
}

/**
 * i40e_release_nvm - Generic request for releasing the NVM ownership
 * @hw: pointer to the HW structure
 *
 * This function will release NVM resource via the proper Admin Command.
 **/
void i40e_release_nvm(struct i40e_hw *hw)
{
	enum i40e_status_code ret_code = I40E_SUCCESS;
	u32 total_delay = 0;

	DEBUGFUNC("i40e_release_nvm");

	if (hw->nvm.blank_nvm_mode)
		return;

	ret_code = i40e_aq_release_resource(hw, I40E_NVM_RESOURCE_ID, 0, NULL);

	/* there are some rare cases when trying to release the resource
	 * results in an admin Q timeout, so handle them correctly
	 */
	while ((ret_code == I40E_ERR_ADMIN_QUEUE_TIMEOUT) &&
	       (total_delay < hw->aq.asq_cmd_timeout)) {
			i40e_msec_delay(1);
			ret_code = i40e_aq_release_resource(hw,
						I40E_NVM_RESOURCE_ID, 0, NULL);
			total_delay++;
	}
}

/**
 * i40e_poll_sr_srctl_done_bit - Polls the GLNVM_SRCTL done bit
 * @hw: pointer to the HW structure
 *
 * Polls the SRCTL Shadow RAM register done bit.
 **/
static enum i40e_status_code i40e_poll_sr_srctl_done_bit(struct i40e_hw *hw)
{
	enum i40e_status_code ret_code = I40E_ERR_TIMEOUT;
	u32 srctl, wait_cnt;

	DEBUGFUNC("i40e_poll_sr_srctl_done_bit");

	/* Poll the I40E_GLNVM_SRCTL until the done bit is set */
	for (wait_cnt = 0; wait_cnt < I40E_SRRD_SRCTL_ATTEMPTS; wait_cnt++) {
		srctl = rd32(hw, I40E_GLNVM_SRCTL);
		if (srctl & I40E_GLNVM_SRCTL_DONE_MASK) {
			ret_code = I40E_SUCCESS;
			break;
		}
		i40e_usec_delay(5);
	}
	if (ret_code == I40E_ERR_TIMEOUT)
		i40e_debug(hw, I40E_DEBUG_NVM, "Done bit in GLNVM_SRCTL not set");
	return ret_code;
}

/**
 * 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 one 16 bit word from the Shadow RAM using the GLNVM_SRCTL register.
 **/
enum i40e_status_code i40e_read_nvm_word(struct i40e_hw *hw, u16 offset,
					 u16 *data)
{
#ifdef X722_SUPPORT
	if (hw->mac.type == I40E_MAC_X722)
		return i40e_read_nvm_word_aq(hw, offset, data);
#endif
	return i40e_read_nvm_word_srctl(hw, offset, data);
}

/**
 * i40e_read_nvm_word_srctl - Reads Shadow RAM via SRCTL register
 * @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 one 16 bit word from the Shadow RAM using the GLNVM_SRCTL register.
 **/
enum i40e_status_code i40e_read_nvm_word_srctl(struct i40e_hw *hw, u16 offset,
					       u16 *data)
{
	enum i40e_status_code ret_code = I40E_ERR_TIMEOUT;
	u32 sr_reg;

	DEBUGFUNC("i40e_read_nvm_word_srctl");

	if (offset >= hw->nvm.sr_size) {
		i40e_debug(hw, I40E_DEBUG_NVM,
			   "NVM read error: Offset %d beyond Shadow RAM limit %d\n",
			   offset, hw->nvm.sr_size);
		ret_code = I40E_ERR_PARAM;
		goto read_nvm_exit;
	}

	/* Poll the done bit first */
	ret_code = i40e_poll_sr_srctl_done_bit(hw);
	if (ret_code == I40E_SUCCESS) {
		/* Write the address and start reading */
		sr_reg = ((u32)offset << I40E_GLNVM_SRCTL_ADDR_SHIFT) |
			 BIT(I40E_GLNVM_SRCTL_START_SHIFT);
		wr32(hw, I40E_GLNVM_SRCTL, sr_reg);

		/* Poll I40E_GLNVM_SRCTL until the done bit is set */
		ret_code = i40e_poll_sr_srctl_done_bit(hw);
		if (ret_code == I40E_SUCCESS) {
			sr_reg = rd32(hw, I40E_GLNVM_SRDATA);
			*data = (u16)((sr_reg &
				       I40E_GLNVM_SRDATA_RDDATA_MASK)
				    >> I40E_GLNVM_SRDATA_RDDATA_SHIFT);
		}
	}
	if (ret_code != I40E_SUCCESS)
		i40e_debug(hw, I40E_DEBUG_NVM,
			   "NVM read error: Couldn't access Shadow RAM address: 0x%x\n",
			   offset);

read_nvm_exit:
	return ret_code;
}

/**
 * i40e_read_nvm_word_aq - Reads Shadow RAM via AQ
 * @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 one 16 bit word from the Shadow RAM using the GLNVM_SRCTL register.
 **/
enum i40e_status_code i40e_read_nvm_word_aq(struct i40e_hw *hw, u16 offset,
					    u16 *data)
{
	enum i40e_status_code ret_code = I40E_ERR_TIMEOUT;

	DEBUGFUNC("i40e_read_nvm_word_aq");

	ret_code = i40e_read_nvm_aq(hw, 0x0, offset, 1, data, TRUE);
	*data = LE16_TO_CPU(*(__le16 *)data);

	return ret_code;
}

/**
 * i40e_read_nvm_buffer - Reads Shadow RAM buffer
 * @hw: pointer to the HW structure
 * @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
 * @words: (in) number of words to read; (out) number of words actually read
 * @data: words read from the Shadow RAM
 *
 * Reads 16 bit words (data buffer) from the SR using the i40e_read_nvm_srrd()
 * method. The buffer read is preceded by the NVM ownership take
 * and followed by the release.
 **/
enum i40e_status_code i40e_read_nvm_buffer(struct i40e_hw *hw, u16 offset,
					   u16 *words, u16 *data)
{
#ifdef X722_SUPPORT
	if (hw->mac.type == I40E_MAC_X722)
		return i40e_read_nvm_buffer_aq(hw, offset, words, data);
#endif
	return i40e_read_nvm_buffer_srctl(hw, offset, words, data);
}

/**
 * i40e_read_nvm_buffer_srctl - Reads Shadow RAM buffer via SRCTL register
 * @hw: pointer to the HW structure
 * @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
 * @words: (in) number of words to read; (out) number of words actually read
 * @data: words read from the Shadow RAM
 *
 * Reads 16 bit words (data buffer) from the SR using the i40e_read_nvm_srrd()
 * method. The buffer read is preceded by the NVM ownership take
 * and followed by the release.
 **/
enum i40e_status_code i40e_read_nvm_buffer_srctl(struct i40e_hw *hw, u16 offset,
						 u16 *words, u16 *data)
{
	enum i40e_status_code ret_code = I40E_SUCCESS;
	u16 index, word;

	DEBUGFUNC("i40e_read_nvm_buffer_srctl");

	/* Loop thru the selected region */
	for (word = 0; word < *words; word++) {
		index = offset + word;
		ret_code = i40e_read_nvm_word_srctl(hw, index, &data[word]);
		if (ret_code != I40E_SUCCESS)
			break;
	}

	/* Update the number of words read from the Shadow RAM */
	*words = word;

	return ret_code;
}

/**
 * i40e_read_nvm_buffer_aq - Reads Shadow RAM buffer via AQ
 * @hw: pointer to the HW structure
 * @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
 * @words: (in) number of words to read; (out) number of words actually read
 * @data: words read from the Shadow RAM
 *
 * Reads 16 bit words (data buffer) from the SR using the i40e_read_nvm_aq()
 * method. The buffer read is preceded by the NVM ownership take
 * and followed by the release.
 **/
enum i40e_status_code i40e_read_nvm_buffer_aq(struct i40e_hw *hw, u16 offset,
					      u16 *words, u16 *data)
{
	enum i40e_status_code ret_code;
	u16 read_size = *words;
	bool last_cmd = FALSE;
	u16 words_read = 0;
	u16 i = 0;

	DEBUGFUNC("i40e_read_nvm_buffer_aq");

	do {
		/* Calculate number of bytes we should read in this step.
		 * FVL AQ do not allow to read more than one page at a time or
		 * to cross page boundaries.
		 */
		if (offset % I40E_SR_SECTOR_SIZE_IN_WORDS)
			read_size = min(*words,
					(u16)(I40E_SR_SECTOR_SIZE_IN_WORDS -
				      (offset % I40E_SR_SECTOR_SIZE_IN_WORDS)));
		else
			read_size = min((*words - words_read),
					I40E_SR_SECTOR_SIZE_IN_WORDS);

		/* Check if this is last command, if so set proper flag */
		if ((words_read + read_size) >= *words)
			last_cmd = TRUE;

		ret_code = i40e_read_nvm_aq(hw, 0x0, offset, read_size,
					    data + words_read, last_cmd);
		if (ret_code != I40E_SUCCESS)
			goto read_nvm_buffer_aq_exit;

		/* Increment counter for words already read and move offset to
		 * new read location
		 */
		words_read += read_size;
		offset += read_size;
	} while (words_read < *words);

	for (i = 0; i < *words; i++)
		data[i] = LE16_TO_CPU(((__le16 *)data)[i]);

read_nvm_buffer_aq_exit:
	*words = words_read;
	return ret_code;
}

/**
 * i40e_read_nvm_aq - Read Shadow RAM.
 * @hw: pointer to the HW structure.
 * @module_pointer: module pointer location in words from the NVM beginning
 * @offset: offset in words from module start
 * @words: number of words to write
 * @data: buffer with words to write to the Shadow RAM
 * @last_command: tells the AdminQ that this is the last command
 *
 * Writes a 16 bit words buffer to the Shadow RAM using the admin command.
 **/
enum i40e_status_code i40e_read_nvm_aq(struct i40e_hw *hw, u8 module_pointer,
				       u32 offset, u16 words, void *data,
				       bool last_command)
{
	enum i40e_status_code ret_code = I40E_ERR_NVM;
	struct i40e_asq_cmd_details cmd_details;

	DEBUGFUNC("i40e_read_nvm_aq");

	memset(&cmd_details, 0, sizeof(cmd_details));
	cmd_details.wb_desc = &hw->nvm_wb_desc;

	/* Here we are checking the SR limit only for the flat memory model.
	 * We cannot do it for the module-based model, as we did not acquire
	 * the NVM resource yet (we cannot get the module pointer value).
	 * Firmware will check the module-based model.
	 */
	if ((offset + words) > hw->nvm.sr_size)
		i40e_debug(hw, I40E_DEBUG_NVM,
			   "NVM write error: offset %d beyond Shadow RAM limit %d\n",
			   (offset + words), hw->nvm.sr_size);
	else if (words > I40E_SR_SECTOR_SIZE_IN_WORDS)
		/* We can write only up to 4KB (one sector), in one AQ write */
		i40e_debug(hw, I40E_DEBUG_NVM,
			   "NVM write fail error: tried to write %d words, limit is %d.\n",
			   words, I40E_SR_SECTOR_SIZE_IN_WORDS);
	else if (((offset + (words - 1)) / I40E_SR_SECTOR_SIZE_IN_WORDS)
		 != (offset / I40E_SR_SECTOR_SIZE_IN_WORDS))
		/* A single write cannot spread over two sectors */
		i40e_debug(hw, I40E_DEBUG_NVM,
			   "NVM write error: cannot spread over two sectors in a single write offset=%d words=%d\n",
			   offset, words);
	else
		ret_code = i40e_aq_read_nvm(hw, module_pointer,
					    2 * offset,  /*bytes*/
					    2 * words,   /*bytes*/
					    data, last_command, &cmd_details);

	return ret_code;
}

/**
 * i40e_write_nvm_aq - Writes Shadow RAM.
 * @hw: pointer to the HW structure.
 * @module_pointer: module pointer location in words from the NVM beginning
 * @offset: offset in words from module start
 * @words: number of words to write
 * @data: buffer with words to write to the Shadow RAM
 * @last_command: tells the AdminQ that this is the last command
 *
 * Writes a 16 bit words buffer to the Shadow RAM using the admin command.
 **/
enum i40e_status_code i40e_write_nvm_aq(struct i40e_hw *hw, u8 module_pointer,
					u32 offset, u16 words, void *data,
					bool last_command)
{
	enum i40e_status_code ret_code = I40E_ERR_NVM;
	struct i40e_asq_cmd_details cmd_details;

	DEBUGFUNC("i40e_write_nvm_aq");

	memset(&cmd_details, 0, sizeof(cmd_details));
	cmd_details.wb_desc = &hw->nvm_wb_desc;

	/* Here we are checking the SR limit only for the flat memory model.
	 * We cannot do it for the module-based model, as we did not acquire
	 * the NVM resource yet (we cannot get the module pointer value).
	 * Firmware will check the module-based model.
	 */
	if ((offset + words) > hw->nvm.sr_size)
		DEBUGOUT("NVM write error: offset beyond Shadow RAM limit.\n");
	else if (words > I40E_SR_SECTOR_SIZE_IN_WORDS)
		/* We can write only up to 4KB (one sector), in one AQ write */
		DEBUGOUT("NVM write fail error: cannot write more than 4KB in a single write.\n");
	else if (((offset + (words - 1)) / I40E_SR_SECTOR_SIZE_IN_WORDS)
		 != (offset / I40E_SR_SECTOR_SIZE_IN_WORDS))
		/* A single write cannot spread over two sectors */
		DEBUGOUT("NVM write error: cannot spread over two sectors in a single write.\n");
	else
		ret_code = i40e_aq_update_nvm(hw, module_pointer,
					      2 * offset,  /*bytes*/
					      2 * words,   /*bytes*/
					      data, last_command, &cmd_details);

	return ret_code;
}

/**
 * i40e_write_nvm_word - Writes Shadow RAM word
 * @hw: pointer to the HW structure
 * @offset: offset of the Shadow RAM word to write
 * @data: word to write to the Shadow RAM
 *
 * Writes a 16 bit word to the SR using the i40e_write_nvm_aq() method.
 * NVM ownership have to be acquired and released (on ARQ completion event
 * reception) by caller. To commit SR to NVM update checksum function
 * should be called.
 **/
enum i40e_status_code i40e_write_nvm_word(struct i40e_hw *hw, u32 offset,
					  void *data)
{
	DEBUGFUNC("i40e_write_nvm_word");

	*((__le16 *)data) = CPU_TO_LE16(*((u16 *)data));

	/* Value 0x00 below means that we treat SR as a flat mem */
	return i40e_write_nvm_aq(hw, 0x00, offset, 1, data, FALSE);
}

/**
 * i40e_write_nvm_buffer - Writes Shadow RAM buffer
 * @hw: pointer to the HW structure
 * @module_pointer: module pointer location in words from the NVM beginning
 * @offset: offset of the Shadow RAM buffer to write
 * @words: number of words to write
 * @data: words to write to the Shadow RAM
 *
 * Writes a 16 bit words buffer to the Shadow RAM using the admin command.
 * NVM ownership must be acquired before calling this function and released
 * on ARQ completion event reception by caller. To commit SR to NVM update
 * checksum function should be called.
 **/
enum i40e_status_code i40e_write_nvm_buffer(struct i40e_hw *hw,
					    u8 module_pointer, u32 offset,
					    u16 words, void *data)
{
	__le16 *le_word_ptr = (__le16 *)data;
	u16 *word_ptr = (u16 *)data;
	u32 i = 0;

	DEBUGFUNC("i40e_write_nvm_buffer");

	for (i = 0; i < words; i++)
		le_word_ptr[i] = CPU_TO_LE16(word_ptr[i]);

	/* Here we will only write one buffer as the size of the modules
	 * mirrored in the Shadow RAM is always less than 4K.
	 */
	return i40e_write_nvm_aq(hw, module_pointer, offset, words,
				 data, FALSE);
}

/**
 * i40e_calc_nvm_checksum - Calculates and returns the checksum
 * @hw: pointer to hardware structure
 * @checksum: pointer to the checksum
 *
 * This function calculates SW Checksum that covers the whole 64kB shadow RAM
 * except the VPD and PCIe ALT Auto-load modules. The structure and size of VPD
 * is customer specific and unknown. Therefore, this function skips all maximum
 * possible size of VPD (1kB).
 **/
enum i40e_status_code i40e_calc_nvm_checksum(struct i40e_hw *hw, u16 *checksum)
{
	enum i40e_status_code ret_code = I40E_SUCCESS;
	struct i40e_virt_mem vmem;
	u16 pcie_alt_module = 0;
	u16 checksum_local = 0;
	u16 vpd_module = 0;
	u16 *data;
	u16 i = 0;

	DEBUGFUNC("i40e_calc_nvm_checksum");

	ret_code = i40e_allocate_virt_mem(hw, &vmem,
				    I40E_SR_SECTOR_SIZE_IN_WORDS * sizeof(u16));
	if (ret_code)
		goto i40e_calc_nvm_checksum_exit;
	data = (u16 *)vmem.va;

	/* read pointer to VPD area */
	ret_code = i40e_read_nvm_word(hw, I40E_SR_VPD_PTR, &vpd_module);
	if (ret_code != I40E_SUCCESS) {
		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_word(hw, I40E_SR_PCIE_ALT_AUTO_LOAD_PTR,
				      &pcie_alt_module);
	if (ret_code != I40E_SUCCESS) {
		ret_code = I40E_ERR_NVM_CHECKSUM;
		goto i40e_calc_nvm_checksum_exit;
	}

	/* Calculate SW checksum that covers the whole 64kB shadow RAM
	 * except the VPD and PCIe ALT Auto-load modules
	 */
	for (i = 0; i < hw->nvm.sr_size; i++) {
		/* Read SR page */
		if ((i % I40E_SR_SECTOR_SIZE_IN_WORDS) == 0) {
			u16 words = I40E_SR_SECTOR_SIZE_IN_WORDS;

			ret_code = i40e_read_nvm_buffer(hw, i, &words, data);
			if (ret_code != I40E_SUCCESS) {
				ret_code = I40E_ERR_NVM_CHECKSUM;
				goto i40e_calc_nvm_checksum_exit;
			}
		}

		/* Skip Checksum word */
		if (i == I40E_SR_SW_CHECKSUM_WORD)
			continue;
		/* Skip VPD module (convert byte size to word count) */
		if ((i >= (u32)vpd_module) &&
		    (i < ((u32)vpd_module +
		     (I40E_SR_VPD_MODULE_MAX_SIZE / 2)))) {
			continue;
		}
		/* Skip PCIe ALT module (convert byte size to word count) */
		if ((i >= (u32)pcie_alt_module) &&
		    (i < ((u32)pcie_alt_module +
		     (I40E_SR_PCIE_ALT_MODULE_MAX_SIZE / 2)))) {
			continue;
		}

		checksum_local += data[i % I40E_SR_SECTOR_SIZE_IN_WORDS];
	}

	*checksum = (u16)I40E_SR_SW_CHECKSUM_BASE - checksum_local;

i40e_calc_nvm_checksum_exit:
	i40e_free_virt_mem(hw, &vmem);
	return ret_code;
}

/**
 * i40e_update_nvm_checksum - Updates the NVM checksum
 * @hw: pointer to hardware structure
 *
 * NVM ownership must be acquired before calling this function and released
 * on ARQ completion event reception by caller.
 * This function will commit SR to NVM.
 **/
enum i40e_status_code i40e_update_nvm_checksum(struct i40e_hw *hw)
{
	enum i40e_status_code ret_code = I40E_SUCCESS;
	u16 checksum;
	__le16 le_sum;

	DEBUGFUNC("i40e_update_nvm_checksum");

	ret_code = i40e_calc_nvm_checksum(hw, &checksum);
	le_sum = CPU_TO_LE16(checksum);
	if (ret_code == I40E_SUCCESS)
		ret_code = i40e_write_nvm_aq(hw, 0x00, I40E_SR_SW_CHECKSUM_WORD,
					     1, &le_sum, TRUE);

	return ret_code;
}

/**
 * i40e_validate_nvm_checksum - Validate EEPROM checksum
 * @hw: pointer to hardware structure
 * @checksum: calculated checksum
 *
 * Performs checksum calculation and validates the NVM SW checksum. If the
 * caller does not need checksum, the value can be NULL.
 **/
enum i40e_status_code i40e_validate_nvm_checksum(struct i40e_hw *hw,
						 u16 *checksum)
{
	enum i40e_status_code ret_code = I40E_SUCCESS;
	u16 checksum_sr = 0;
	u16 checksum_local = 0;

	DEBUGFUNC("i40e_validate_nvm_checksum");

	ret_code = i40e_calc_nvm_checksum(hw, &checksum_local);
	if (ret_code != I40E_SUCCESS)
		goto i40e_validate_nvm_checksum_exit;

	/* Do not use i40e_read_nvm_word() because we do not want to take
	 * the synchronization semaphores twice here.
	 */
	i40e_read_nvm_word(hw, I40E_SR_SW_CHECKSUM_WORD, &checksum_sr);

	/* Verify read checksum from EEPROM is the same as
	 * calculated checksum
	 */
	if (checksum_local != checksum_sr)
		ret_code = I40E_ERR_NVM_CHECKSUM;

	/* If the user cares, return the calculated checksum */
	if (checksum)
		*checksum = checksum_local;

i40e_validate_nvm_checksum_exit:
	return ret_code;
}