drivers/net/wireless/iwlwifi/mvm/nvm.c - kernel/msm-4.19 - Gitiles

 /******************************************************************************
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
  *
  * GPL LICENSE SUMMARY
  *
  * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
  * published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
  * USA
  *
  * The full GNU General Public License is included in this distribution
  * in the file called COPYING.
  *
  * Contact Information:
  *  Intel Linux Wireless <ilw@linux.intel.com>
  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  *
  * BSD LICENSE
  *
  * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *  * Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *  * Neither the name Intel Corporation nor the names of its
  *    contributors may be used to endorse or promote products derived
  *    from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  *****************************************************************************/
 #include <linux/firmware.h>
 #include "iwl-trans.h"
 #include "mvm.h"
 #include "iwl-eeprom-parse.h"
 #include "iwl-eeprom-read.h"
 #include "iwl-nvm-parse.h"

 /* list of NVM sections we are allowed/need to read */
 static const int nvm_to_read[] = {
 	NVM_SECTION_TYPE_HW,
 	NVM_SECTION_TYPE_SW,
 	NVM_SECTION_TYPE_CALIBRATION,
 	NVM_SECTION_TYPE_PRODUCTION,
 };

 /* Default NVM size to read */
 #define IWL_NVM_DEFAULT_CHUNK_SIZE (2*1024)
 #define IWL_MAX_NVM_SECTION_SIZE 7000

 #define NVM_WRITE_OPCODE 1
 #define NVM_READ_OPCODE 0

 /*
  * prepare the NVM host command w/ the pointers to the nvm buffer
  * and send it to fw
  */
 static int iwl_nvm_write_chunk(struct iwl_mvm *mvm, u16 section,
 			       u16 offset, u16 length, const u8 *data)
 {
 	struct iwl_nvm_access_cmd nvm_access_cmd = {
 		.offset = cpu_to_le16(offset),
 		.length = cpu_to_le16(length),
 		.type = cpu_to_le16(section),
 		.op_code = NVM_WRITE_OPCODE,
 	};
 	struct iwl_host_cmd cmd = {
 		.id = NVM_ACCESS_CMD,
 		.len = { sizeof(struct iwl_nvm_access_cmd), length },
 		.flags = CMD_SYNC | CMD_SEND_IN_RFKILL,
 		.data = { &nvm_access_cmd, data },
 		/* data may come from vmalloc, so use _DUP */
 		.dataflags = { 0, IWL_HCMD_DFL_DUP },
 	};

 	return iwl_mvm_send_cmd(mvm, &cmd);
 }

 static int iwl_nvm_read_chunk(struct iwl_mvm *mvm, u16 section,
 			      u16 offset, u16 length, u8 *data)
 {
 	struct iwl_nvm_access_cmd nvm_access_cmd = {
 		.offset = cpu_to_le16(offset),
 		.length = cpu_to_le16(length),
 		.type = cpu_to_le16(section),
 		.op_code = NVM_READ_OPCODE,
 	};
 	struct iwl_nvm_access_resp *nvm_resp;
 	struct iwl_rx_packet *pkt;
 	struct iwl_host_cmd cmd = {
 		.id = NVM_ACCESS_CMD,
 		.flags = CMD_SYNC | CMD_WANT_SKB | CMD_SEND_IN_RFKILL,
 		.data = { &nvm_access_cmd, },
 	};
 	int ret, bytes_read, offset_read;
 	u8 *resp_data;

 	cmd.len[0] = sizeof(struct iwl_nvm_access_cmd);

 	ret = iwl_mvm_send_cmd(mvm, &cmd);
 	if (ret)
 		return ret;

 	pkt = cmd.resp_pkt;
 	if (pkt->hdr.flags & IWL_CMD_FAILED_MSK) {
 		IWL_ERR(mvm, "Bad return from NVM_ACCES_COMMAND (0x%08X)\n",
 			pkt->hdr.flags);
 		ret = -EIO;
 		goto exit;
 	}

 	/* Extract NVM response */
 	nvm_resp = (void *)pkt->data;
 	ret = le16_to_cpu(nvm_resp->status);
 	bytes_read = le16_to_cpu(nvm_resp->length);
 	offset_read = le16_to_cpu(nvm_resp->offset);
 	resp_data = nvm_resp->data;
 	if (ret) {
 		IWL_ERR(mvm,
 			"NVM access command failed with status %d (device: %s)\n",
 			ret, mvm->cfg->name);
 		ret = -EINVAL;
 		goto exit;
 	}

 	if (offset_read != offset) {
 		IWL_ERR(mvm, "NVM ACCESS response with invalid offset %d\n",
 			offset_read);
 		ret = -EINVAL;
 		goto exit;
 	}

 	/* Write data to NVM */
 	memcpy(data + offset, resp_data, bytes_read);
 	ret = bytes_read;

 exit:
 	iwl_free_resp(&cmd);
 	return ret;
 }

 static int iwl_nvm_write_section(struct iwl_mvm *mvm, u16 section,
 				 const u8 *data, u16 length)
 {
 	int offset = 0;

 	/* copy data in chunks of 2k (and remainder if any) */

 	while (offset < length) {
 		int chunk_size, ret;

 		chunk_size = min(IWL_NVM_DEFAULT_CHUNK_SIZE,
 				 length - offset);

 		ret = iwl_nvm_write_chunk(mvm, section, offset,
 					  chunk_size, data + offset);
 		if (ret < 0)
 			return ret;

 		offset += chunk_size;
 	}

 	return 0;
 }

 /*
  * Reads an NVM section completely.
  * NICs prior to 7000 family doesn't have a real NVM, but just read
  * section 0 which is the EEPROM. Because the EEPROM reading is unlimited
  * by uCode, we need to manually check in this case that we don't
  * overflow and try to read more than the EEPROM size.
  * For 7000 family NICs, we supply the maximal size we can read, and
  * the uCode fills the response with as much data as we can,
  * without overflowing, so no check is needed.
  */
 static int iwl_nvm_read_section(struct iwl_mvm *mvm, u16 section,
 				u8 *data)
 {
 	u16 length, offset = 0;
 	int ret;

 	/* Set nvm section read length */
 	length = IWL_NVM_DEFAULT_CHUNK_SIZE;

 	ret = length;

 	/* Read the NVM until exhausted (reading less than requested) */
 	while (ret == length) {
 		ret = iwl_nvm_read_chunk(mvm, section, offset, length, data);
 		if (ret < 0) {
 			IWL_ERR(mvm,
 				"Cannot read NVM from section %d offset %d, length %d\n",
 				section, offset, length);
 			return ret;
 		}
 		offset += ret;
 	}

 	IWL_DEBUG_EEPROM(mvm->trans->dev,
 			 "NVM section %d read completed\n", section);
 	return offset;
 }

 static struct iwl_nvm_data *
 iwl_parse_nvm_sections(struct iwl_mvm *mvm)
 {
 	struct iwl_nvm_section *sections = mvm->nvm_sections;
 	const __le16 *hw, *sw, *calib;

 	/* Checking for required sections */
 	if (!mvm->nvm_sections[NVM_SECTION_TYPE_SW].data ||
 	    !mvm->nvm_sections[NVM_SECTION_TYPE_HW].data) {
 		IWL_ERR(mvm, "Can't parse empty NVM sections\n");
 		return NULL;
 	}

 	if (WARN_ON(!mvm->cfg))
 		return NULL;

 	hw = (const __le16 *)sections[NVM_SECTION_TYPE_HW].data;
 	sw = (const __le16 *)sections[NVM_SECTION_TYPE_SW].data;
 	calib = (const __le16 *)sections[NVM_SECTION_TYPE_CALIBRATION].data;
 	return iwl_parse_nvm_data(mvm->trans->dev, mvm->cfg, hw, sw, calib,
 				  iwl_fw_valid_tx_ant(mvm->fw),
 				  iwl_fw_valid_rx_ant(mvm->fw));
 }

 #define MAX_NVM_FILE_LEN	16384

 /*
  * Reads external NVM from a file into mvm->nvm_sections
  *
  * HOW TO CREATE THE NVM FILE FORMAT:
  * ------------------------------
  * 1. create hex file, format:
  *      3800 -> header
  *      0000 -> header
  *      5a40 -> data
  *
  *   rev - 6 bit (word1)
  *   len - 10 bit (word1)
  *   id - 4 bit (word2)
  *   rsv - 12 bit (word2)
  *
  * 2. flip 8bits with 8 bits per line to get the right NVM file format
  *
  * 3. create binary file from the hex file
  *
  * 4. save as "iNVM_xxx.bin" under /lib/firmware
  */
 static int iwl_mvm_read_external_nvm(struct iwl_mvm *mvm)
 {
 	int ret, section_size;
 	u16 section_id;
 	const struct firmware *fw_entry;
 	const struct {
 		__le16 word1;
 		__le16 word2;
 		u8 data[];
 	} *file_sec;
 	const u8 *eof, *temp;

 #define NVM_WORD1_LEN(x) (8 * (x & 0x03FF))
 #define NVM_WORD2_ID(x) (x >> 12)

 	IWL_DEBUG_EEPROM(mvm->trans->dev, "Read from external NVM\n");

 	/*
 	 * Obtain NVM image via request_firmware. Since we already used
 	 * request_firmware_nowait() for the firmware binary load and only
 	 * get here after that we assume the NVM request can be satisfied
 	 * synchronously.
 	 */
 	ret = request_firmware(&fw_entry, iwlwifi_mod_params.nvm_file,
 			       mvm->trans->dev);
 	if (ret) {
 		IWL_ERR(mvm, "ERROR: %s isn't available %d\n",
 			iwlwifi_mod_params.nvm_file, ret);
 		return ret;
 	}

 	IWL_INFO(mvm, "Loaded NVM file %s (%zu bytes)\n",
 		 iwlwifi_mod_params.nvm_file, fw_entry->size);

 	if (fw_entry->size < sizeof(*file_sec)) {
 		IWL_ERR(mvm, "NVM file too small\n");
 		ret = -EINVAL;
 		goto out;
 	}

 	if (fw_entry->size > MAX_NVM_FILE_LEN) {
 		IWL_ERR(mvm, "NVM file too large\n");
 		ret = -EINVAL;
 		goto out;
 	}

 	eof = fw_entry->data + fw_entry->size;

 	file_sec = (void *)fw_entry->data;

 	while (true) {
 		if (file_sec->data > eof) {
 			IWL_ERR(mvm,
 				"ERROR - NVM file too short for section header\n");
 			ret = -EINVAL;
 			break;
 		}

 		/* check for EOF marker */
 		if (!file_sec->word1 && !file_sec->word2) {
 			ret = 0;
 			break;
 		}

 		section_size = 2 * NVM_WORD1_LEN(le16_to_cpu(file_sec->word1));
 		section_id = NVM_WORD2_ID(le16_to_cpu(file_sec->word2));

 		if (section_size > IWL_MAX_NVM_SECTION_SIZE) {
 			IWL_ERR(mvm, "ERROR - section too large (%d)\n",
 				section_size);
 			ret = -EINVAL;
 			break;
 		}

 		if (!section_size) {
 			IWL_ERR(mvm, "ERROR - section empty\n");
 			ret = -EINVAL;
 			break;
 		}

 		if (file_sec->data + section_size > eof) {
 			IWL_ERR(mvm,
 				"ERROR - NVM file too short for section (%d bytes)\n",
 				section_size);
 			ret = -EINVAL;
 			break;
 		}

 		temp = kmemdup(file_sec->data, section_size, GFP_KERNEL);
 		if (!temp) {
 			ret = -ENOMEM;
 			break;
 		}
 		if (WARN_ON(section_id >= NVM_NUM_OF_SECTIONS)) {
 			IWL_ERR(mvm, "Invalid NVM section ID\n");
 			ret = -EINVAL;
 			break;
 		}
 		mvm->nvm_sections[section_id].data = temp;
 		mvm->nvm_sections[section_id].length = section_size;

 		/* advance to the next section */
 		file_sec = (void *)(file_sec->data + section_size);
 	}
 out:
 	release_firmware(fw_entry);
 	return ret;
 }

 /* Loads the NVM data stored in mvm->nvm_sections into the NIC */
 int iwl_mvm_load_nvm_to_nic(struct iwl_mvm *mvm)
 {
 	int i, ret;
 	u16 section_id;
 	struct iwl_nvm_section *sections = mvm->nvm_sections;

 	IWL_DEBUG_EEPROM(mvm->trans->dev, "'Write to NVM\n");

 	for (i = 0; i < ARRAY_SIZE(nvm_to_read); i++) {
 		section_id = nvm_to_read[i];
 		ret = iwl_nvm_write_section(mvm, section_id,
 					    sections[section_id].data,
 					    sections[section_id].length);
 		if (ret < 0) {
 			IWL_ERR(mvm, "iwl_mvm_send_cmd failed: %d\n", ret);
 			break;
 		}
 	}
 	return ret;
 }

 int iwl_nvm_init(struct iwl_mvm *mvm)
 {
 	int ret, i, section;
 	u8 *nvm_buffer, *temp;

 	/* load external NVM if configured */
 	if (iwlwifi_mod_params.nvm_file) {
 		/* move to External NVM flow */
 		ret = iwl_mvm_read_external_nvm(mvm);
 		if (ret)
 			return ret;
 	} else {
 		/* Read From FW NVM */
 		IWL_DEBUG_EEPROM(mvm->trans->dev, "Read from NVM\n");

 		/* TODO: find correct NVM max size for a section */
 		nvm_buffer = kmalloc(mvm->cfg->base_params->eeprom_size,
 				     GFP_KERNEL);
 		if (!nvm_buffer)
 			return -ENOMEM;
 		for (i = 0; i < ARRAY_SIZE(nvm_to_read); i++) {
 			section = nvm_to_read[i];
 			/* we override the constness for initial read */
 			ret = iwl_nvm_read_section(mvm, section, nvm_buffer);
 			if (ret < 0)
 				break;
 			temp = kmemdup(nvm_buffer, ret, GFP_KERNEL);
 			if (!temp) {
 				ret = -ENOMEM;
 				break;
 			}
 			mvm->nvm_sections[section].data = temp;
 			mvm->nvm_sections[section].length = ret;
 		}
 		kfree(nvm_buffer);
 		if (ret < 0)
 			return ret;
 	}

 	mvm->nvm_data = iwl_parse_nvm_sections(mvm);
 	if (!mvm->nvm_data)
 		return -ENODATA;

 	return 0;
 }
	/******************************************************************************
	*
	* This file is provided under a dual BSD/GPLv2 license. When using or
	* redistributing this file, you may do so under either license.
	*
	* GPL LICENSE SUMMARY
	*
	* Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of version 2 of the GNU General Public License as
	* published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
	* USA
	*
	* The full GNU General Public License is included in this distribution
	* in the file called COPYING.
	*
	* Contact Information:
	* Intel Linux Wireless <ilw@linux.intel.com>
	* Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
	*
	* BSD LICENSE
	*
	* Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* * Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* * Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	* * Neither the name Intel Corporation nor the names of its
	* contributors may be used to endorse or promote products derived
	* from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	*****************************************************************************/
	#include <linux/firmware.h>
	#include "iwl-trans.h"
	#include "mvm.h"
	#include "iwl-eeprom-parse.h"
	#include "iwl-eeprom-read.h"
	#include "iwl-nvm-parse.h"

	/* list of NVM sections we are allowed/need to read */
	static const int nvm_to_read[] = {
	NVM_SECTION_TYPE_HW,
	NVM_SECTION_TYPE_SW,
	NVM_SECTION_TYPE_CALIBRATION,
	NVM_SECTION_TYPE_PRODUCTION,
	};

	/* Default NVM size to read */
	#define IWL_NVM_DEFAULT_CHUNK_SIZE (2*1024)
	#define IWL_MAX_NVM_SECTION_SIZE 7000

	#define NVM_WRITE_OPCODE 1
	#define NVM_READ_OPCODE 0

	/*
	* prepare the NVM host command w/ the pointers to the nvm buffer
	* and send it to fw
	*/
	static int iwl_nvm_write_chunk(struct iwl_mvm *mvm, u16 section,
	u16 offset, u16 length, const u8 *data)
	{
	struct iwl_nvm_access_cmd nvm_access_cmd = {
	.offset = cpu_to_le16(offset),
	.length = cpu_to_le16(length),
	.type = cpu_to_le16(section),
	.op_code = NVM_WRITE_OPCODE,
	};
	struct iwl_host_cmd cmd = {
	.id = NVM_ACCESS_CMD,
	.len = { sizeof(struct iwl_nvm_access_cmd), length },
	.flags = CMD_SYNC \| CMD_SEND_IN_RFKILL,
	.data = { &nvm_access_cmd, data },
	/* data may come from vmalloc, so use _DUP */
	.dataflags = { 0, IWL_HCMD_DFL_DUP },
	};

	return iwl_mvm_send_cmd(mvm, &cmd);
	}

	static int iwl_nvm_read_chunk(struct iwl_mvm *mvm, u16 section,
	u16 offset, u16 length, u8 *data)
	{
	struct iwl_nvm_access_cmd nvm_access_cmd = {
	.offset = cpu_to_le16(offset),
	.length = cpu_to_le16(length),
	.type = cpu_to_le16(section),
	.op_code = NVM_READ_OPCODE,
	};
	struct iwl_nvm_access_resp *nvm_resp;
	struct iwl_rx_packet *pkt;
	struct iwl_host_cmd cmd = {
	.id = NVM_ACCESS_CMD,
	.flags = CMD_SYNC \| CMD_WANT_SKB \| CMD_SEND_IN_RFKILL,
	.data = { &nvm_access_cmd, },
	};
	int ret, bytes_read, offset_read;
	u8 *resp_data;

	cmd.len[0] = sizeof(struct iwl_nvm_access_cmd);

	ret = iwl_mvm_send_cmd(mvm, &cmd);
	if (ret)
	return ret;

	pkt = cmd.resp_pkt;
	if (pkt->hdr.flags & IWL_CMD_FAILED_MSK) {
	IWL_ERR(mvm, "Bad return from NVM_ACCES_COMMAND (0x%08X)\n",
	pkt->hdr.flags);
	ret = -EIO;
	goto exit;
	}

	/* Extract NVM response */
	nvm_resp = (void *)pkt->data;
	ret = le16_to_cpu(nvm_resp->status);
	bytes_read = le16_to_cpu(nvm_resp->length);
	offset_read = le16_to_cpu(nvm_resp->offset);
	resp_data = nvm_resp->data;
	if (ret) {
	IWL_ERR(mvm,
	"NVM access command failed with status %d (device: %s)\n",
	ret, mvm->cfg->name);
	ret = -EINVAL;
	goto exit;
	}

	if (offset_read != offset) {
	IWL_ERR(mvm, "NVM ACCESS response with invalid offset %d\n",
	offset_read);
	ret = -EINVAL;
	goto exit;
	}

	/* Write data to NVM */
	memcpy(data + offset, resp_data, bytes_read);
	ret = bytes_read;

	exit:
	iwl_free_resp(&cmd);
	return ret;
	}

	static int iwl_nvm_write_section(struct iwl_mvm *mvm, u16 section,
	const u8 *data, u16 length)
	{
	int offset = 0;

	/* copy data in chunks of 2k (and remainder if any) */

	while (offset < length) {
	int chunk_size, ret;

	chunk_size = min(IWL_NVM_DEFAULT_CHUNK_SIZE,
	length - offset);

	ret = iwl_nvm_write_chunk(mvm, section, offset,
	chunk_size, data + offset);
	if (ret < 0)
	return ret;

	offset += chunk_size;
	}

	return 0;
	}

	/*
	* Reads an NVM section completely.
	* NICs prior to 7000 family doesn't have a real NVM, but just read
	* section 0 which is the EEPROM. Because the EEPROM reading is unlimited
	* by uCode, we need to manually check in this case that we don't
	* overflow and try to read more than the EEPROM size.
	* For 7000 family NICs, we supply the maximal size we can read, and
	* the uCode fills the response with as much data as we can,
	* without overflowing, so no check is needed.
	*/
	static int iwl_nvm_read_section(struct iwl_mvm *mvm, u16 section,
	u8 *data)
	{
	u16 length, offset = 0;
	int ret;

	/* Set nvm section read length */
	length = IWL_NVM_DEFAULT_CHUNK_SIZE;

	ret = length;

	/* Read the NVM until exhausted (reading less than requested) */
	while (ret == length) {
	ret = iwl_nvm_read_chunk(mvm, section, offset, length, data);
	if (ret < 0) {
	IWL_ERR(mvm,
	"Cannot read NVM from section %d offset %d, length %d\n",
	section, offset, length);
	return ret;
	}
	offset += ret;
	}

	IWL_DEBUG_EEPROM(mvm->trans->dev,
	"NVM section %d read completed\n", section);
	return offset;
	}

	static struct iwl_nvm_data *
	iwl_parse_nvm_sections(struct iwl_mvm *mvm)
	{
	struct iwl_nvm_section *sections = mvm->nvm_sections;
	const __le16 hw, sw, *calib;

	/* Checking for required sections */
	if (!mvm->nvm_sections[NVM_SECTION_TYPE_SW].data \|\|
	!mvm->nvm_sections[NVM_SECTION_TYPE_HW].data) {
	IWL_ERR(mvm, "Can't parse empty NVM sections\n");
	return NULL;
	}

	if (WARN_ON(!mvm->cfg))
	return NULL;

	hw = (const __le16 *)sections[NVM_SECTION_TYPE_HW].data;
	sw = (const __le16 *)sections[NVM_SECTION_TYPE_SW].data;
	calib = (const __le16 *)sections[NVM_SECTION_TYPE_CALIBRATION].data;
	return iwl_parse_nvm_data(mvm->trans->dev, mvm->cfg, hw, sw, calib,
	iwl_fw_valid_tx_ant(mvm->fw),
	iwl_fw_valid_rx_ant(mvm->fw));
	}

	#define MAX_NVM_FILE_LEN 16384

	/*
	* Reads external NVM from a file into mvm->nvm_sections
	*
	* HOW TO CREATE THE NVM FILE FORMAT:
	* ------------------------------
	* 1. create hex file, format:
	* 3800 -> header
	* 0000 -> header
	* 5a40 -> data
	*
	* rev - 6 bit (word1)
	* len - 10 bit (word1)
	* id - 4 bit (word2)
	* rsv - 12 bit (word2)
	*
	* 2. flip 8bits with 8 bits per line to get the right NVM file format
	*
	* 3. create binary file from the hex file
	*
	* 4. save as "iNVM_xxx.bin" under /lib/firmware
	*/
	static int iwl_mvm_read_external_nvm(struct iwl_mvm *mvm)
	{
	int ret, section_size;
	u16 section_id;
	const struct firmware *fw_entry;
	const struct {
	__le16 word1;
	__le16 word2;
	u8 data[];
	} *file_sec;
	const u8 eof, temp;

	#define NVM_WORD1_LEN(x) (8 * (x & 0x03FF))
	#define NVM_WORD2_ID(x) (x >> 12)

	IWL_DEBUG_EEPROM(mvm->trans->dev, "Read from external NVM\n");

	/*
	* Obtain NVM image via request_firmware. Since we already used
	* request_firmware_nowait() for the firmware binary load and only
	* get here after that we assume the NVM request can be satisfied
	* synchronously.
	*/
	ret = request_firmware(&fw_entry, iwlwifi_mod_params.nvm_file,
	mvm->trans->dev);
	if (ret) {
	IWL_ERR(mvm, "ERROR: %s isn't available %d\n",
	iwlwifi_mod_params.nvm_file, ret);
	return ret;
	}

	IWL_INFO(mvm, "Loaded NVM file %s (%zu bytes)\n",
	iwlwifi_mod_params.nvm_file, fw_entry->size);

	if (fw_entry->size < sizeof(*file_sec)) {
	IWL_ERR(mvm, "NVM file too small\n");
	ret = -EINVAL;
	goto out;
	}

	if (fw_entry->size > MAX_NVM_FILE_LEN) {
	IWL_ERR(mvm, "NVM file too large\n");
	ret = -EINVAL;
	goto out;
	}

	eof = fw_entry->data + fw_entry->size;

	file_sec = (void *)fw_entry->data;

	while (true) {
	if (file_sec->data > eof) {
	IWL_ERR(mvm,
	"ERROR - NVM file too short for section header\n");
	ret = -EINVAL;
	break;
	}

	/* check for EOF marker */
	if (!file_sec->word1 && !file_sec->word2) {
	ret = 0;
	break;
	}

	section_size = 2 * NVM_WORD1_LEN(le16_to_cpu(file_sec->word1));
	section_id = NVM_WORD2_ID(le16_to_cpu(file_sec->word2));

	if (section_size > IWL_MAX_NVM_SECTION_SIZE) {
	IWL_ERR(mvm, "ERROR - section too large (%d)\n",
	section_size);
	ret = -EINVAL;
	break;
	}

	if (!section_size) {
	IWL_ERR(mvm, "ERROR - section empty\n");
	ret = -EINVAL;
	break;
	}

	if (file_sec->data + section_size > eof) {
	IWL_ERR(mvm,
	"ERROR - NVM file too short for section (%d bytes)\n",
	section_size);
	ret = -EINVAL;
	break;
	}

	temp = kmemdup(file_sec->data, section_size, GFP_KERNEL);
	if (!temp) {
	ret = -ENOMEM;
	break;
	}
	if (WARN_ON(section_id >= NVM_NUM_OF_SECTIONS)) {
	IWL_ERR(mvm, "Invalid NVM section ID\n");
	ret = -EINVAL;
	break;
	}
	mvm->nvm_sections[section_id].data = temp;
	mvm->nvm_sections[section_id].length = section_size;

	/* advance to the next section */
	file_sec = (void *)(file_sec->data + section_size);
	}
	out:
	release_firmware(fw_entry);
	return ret;
	}

	/* Loads the NVM data stored in mvm->nvm_sections into the NIC */
	int iwl_mvm_load_nvm_to_nic(struct iwl_mvm *mvm)
	{
	int i, ret;
	u16 section_id;
	struct iwl_nvm_section *sections = mvm->nvm_sections;

	IWL_DEBUG_EEPROM(mvm->trans->dev, "'Write to NVM\n");

	for (i = 0; i < ARRAY_SIZE(nvm_to_read); i++) {
	section_id = nvm_to_read[i];
	ret = iwl_nvm_write_section(mvm, section_id,
	sections[section_id].data,
	sections[section_id].length);
	if (ret < 0) {
	IWL_ERR(mvm, "iwl_mvm_send_cmd failed: %d\n", ret);
	break;
	}
	}
	return ret;
	}

	int iwl_nvm_init(struct iwl_mvm *mvm)
	{
	int ret, i, section;
	u8 nvm_buffer, temp;

	/* load external NVM if configured */
	if (iwlwifi_mod_params.nvm_file) {
	/* move to External NVM flow */
	ret = iwl_mvm_read_external_nvm(mvm);
	if (ret)
	return ret;
	} else {
	/* Read From FW NVM */
	IWL_DEBUG_EEPROM(mvm->trans->dev, "Read from NVM\n");

	/* TODO: find correct NVM max size for a section */
	nvm_buffer = kmalloc(mvm->cfg->base_params->eeprom_size,
	GFP_KERNEL);
	if (!nvm_buffer)
	return -ENOMEM;
	for (i = 0; i < ARRAY_SIZE(nvm_to_read); i++) {
	section = nvm_to_read[i];
	/* we override the constness for initial read */
	ret = iwl_nvm_read_section(mvm, section, nvm_buffer);
	if (ret < 0)
	break;
	temp = kmemdup(nvm_buffer, ret, GFP_KERNEL);
	if (!temp) {
	ret = -ENOMEM;
	break;
	}
	mvm->nvm_sections[section].data = temp;
	mvm->nvm_sections[section].length = ret;
	}
	kfree(nvm_buffer);
	if (ret < 0)
	return ret;
	}

	mvm->nvm_data = iwl_parse_nvm_sections(mvm);
	if (!mvm->nvm_data)
	return -ENODATA;

	return 0;
	}