/******************************************************************************
*
* 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) 2008 - 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 LICENSE.GPL.
*
* 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) 2005 - 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/types.h>
#include <linux/slab.h>
#include <linux/export.h>
#include "iwl-debug.h"
#include "iwl-eeprom-read.h"
#include "iwl-io.h"
#include "iwl-prph.h"
#include "iwl-csr.h"
/*
* EEPROM access time values:
*
* Driver initiates EEPROM read by writing byte address << 1 to CSR_EEPROM_REG.
* Driver then polls CSR_EEPROM_REG for CSR_EEPROM_REG_READ_VALID_MSK (0x1).
* When polling, wait 10 uSec between polling loops, up to a maximum 5000 uSec.
* Driver reads 16-bit value from bits 31-16 of CSR_EEPROM_REG.
*/
#define IWL_EEPROM_ACCESS_TIMEOUT 5000 /* uSec */
#define IWL_EEPROM_SEM_TIMEOUT 10 /* microseconds */
#define IWL_EEPROM_SEM_RETRY_LIMIT 1000 /* number of attempts (not time) */
/*
* The device's EEPROM semaphore prevents conflicts between driver and uCode
* when accessing the EEPROM; each access is a series of pulses to/from the
* EEPROM chip, not a single event, so even reads could conflict if they
* weren't arbitrated by the semaphore.
*/
#define EEPROM_SEM_TIMEOUT 10 /* milliseconds */
#define EEPROM_SEM_RETRY_LIMIT 1000 /* number of attempts (not time) */
static int iwl_eeprom_acquire_semaphore(struct iwl_trans *trans)
{
u16 count;
int ret;
for (count = 0; count < EEPROM_SEM_RETRY_LIMIT; count++) {
/* Request semaphore */
iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
/* See if we got it */
ret = iwl_poll_bit(trans, CSR_HW_IF_CONFIG_REG,
CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
EEPROM_SEM_TIMEOUT);
if (ret >= 0) {
IWL_DEBUG_EEPROM(trans->dev,
"Acquired semaphore after %d tries.\n",
count+1);
return ret;
}
}
return ret;
}
static void iwl_eeprom_release_semaphore(struct iwl_trans *trans)
{
iwl_clear_bit(trans, CSR_HW_IF_CONFIG_REG,
CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
}
static int iwl_eeprom_verify_signature(struct iwl_trans *trans, bool nvm_is_otp)
{
u32 gp = iwl_read32(trans, CSR_EEPROM_GP) & CSR_EEPROM_GP_VALID_MSK;
IWL_DEBUG_EEPROM(trans->dev, "EEPROM signature=0x%08x\n", gp);
switch (gp) {
case CSR_EEPROM_GP_BAD_SIG_EEP_GOOD_SIG_OTP:
if (!nvm_is_otp) {
IWL_ERR(trans, "EEPROM with bad signature: 0x%08x\n",
gp);
return -ENOENT;
}
return 0;
case CSR_EEPROM_GP_GOOD_SIG_EEP_LESS_THAN_4K:
case CSR_EEPROM_GP_GOOD_SIG_EEP_MORE_THAN_4K:
if (nvm_is_otp) {
IWL_ERR(trans, "OTP with bad signature: 0x%08x\n", gp);
return -ENOENT;
}
return 0;
case CSR_EEPROM_GP_BAD_SIGNATURE_BOTH_EEP_AND_OTP:
default:
IWL_ERR(trans,
"bad EEPROM/OTP signature, type=%s, EEPROM_GP=0x%08x\n",
nvm_is_otp ? "OTP" : "EEPROM", gp);
return -ENOENT;
}
}
/******************************************************************************
*
* OTP related functions
*
******************************************************************************/
static void iwl_set_otp_access_absolute(struct iwl_trans *trans)
{
iwl_read32(trans, CSR_OTP_GP_REG);
iwl_clear_bit(trans, CSR_OTP_GP_REG,
CSR_OTP_GP_REG_OTP_ACCESS_MODE);
}
static int iwl_nvm_is_otp(struct iwl_trans *trans)
{
u32 otpgp;
/* OTP only valid for CP/PP and after */
switch (trans->hw_rev & CSR_HW_REV_TYPE_MSK) {
case CSR_HW_REV_TYPE_NONE:
IWL_ERR(trans, "Unknown hardware type\n");
return -EIO;
case CSR_HW_REV_TYPE_5300:
case CSR_HW_REV_TYPE_5350:
case CSR_HW_REV_TYPE_5100:
case CSR_HW_REV_TYPE_5150:
return 0;
default:
otpgp = iwl_read32(trans, CSR_OTP_GP_REG);
if (otpgp & CSR_OTP_GP_REG_DEVICE_SELECT)
return 1;
return 0;
}
}
static int iwl_init_otp_access(struct iwl_trans *trans)
{
int ret;
/* Enable 40MHz radio clock */
iwl_write32(trans, CSR_GP_CNTRL,
iwl_read32(trans, CSR_GP_CNTRL) |
CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
/* wait for clock to be ready */
ret = iwl_poll_bit(trans, CSR_GP_CNTRL,
CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
25000);
if (ret < 0) {
IWL_ERR(trans, "Time out access OTP\n");
} else {
iwl_set_bits_prph(trans, APMG_PS_CTRL_REG,
APMG_PS_CTRL_VAL_RESET_REQ);
udelay(5);
iwl_clear_bits_prph(trans, APMG_PS_CTRL_REG,
APMG_PS_CTRL_VAL_RESET_REQ);
/*
* CSR auto clock gate disable bit -
* this is only applicable for HW with OTP shadow RAM
*/
if (trans->cfg->base_params->shadow_ram_support)
iwl_set_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
CSR_RESET_LINK_PWR_MGMT_DISABLED);
}
return ret;
}
static int iwl_read_otp_word(struct iwl_trans *trans, u16 addr,
__le16 *eeprom_data)
{
int ret = 0;
u32 r;
u32 otpgp;
iwl_write32(trans, CSR_EEPROM_REG,
CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
ret = iwl_poll_bit(trans, CSR_EEPROM_REG,
CSR_EEPROM_REG_READ_VALID_MSK,
CSR_EEPROM_REG_READ_VALID_MSK,
IWL_EEPROM_ACCESS_TIMEOUT);
if (ret < 0) {
IWL_ERR(trans, "Time out reading OTP[%d]\n", addr);
return ret;
}
r = iwl_read32(trans, CSR_EEPROM_REG);
/* check for ECC errors: */
otpgp = iwl_read32(trans, CSR_OTP_GP_REG);
if (otpgp & CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK) {
/* stop in this case */
/* set the uncorrectable OTP ECC bit for acknowledgement */
iwl_set_bit(trans, CSR_OTP_GP_REG,
CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
IWL_ERR(trans, "Uncorrectable OTP ECC error, abort OTP read\n");
return -EINVAL;
}
if (otpgp & CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK) {
/* continue in this case */
/* set the correctable OTP ECC bit for acknowledgement */
iwl_set_bit(trans, CSR_OTP_GP_REG,
CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK);
IWL_ERR(trans, "Correctable OTP ECC error, continue read\n");
}
*eeprom_data = cpu_to_le16(r >> 16);
return 0;
}
/*
* iwl_is_otp_empty: check for empty OTP
*/
static bool iwl_is_otp_empty(struct iwl_trans *trans)
{
u16 next_link_addr = 0;
__le16 link_value;
bool is_empty = false;
/* locate the beginning of OTP link list */
if (!iwl_read_otp_word(trans, next_link_addr, &link_value)) {
if (!link_value) {
IWL_ERR(trans, "OTP is empty\n");
is_empty = true;
}
} else {
IWL_ERR(trans, "Unable to read first block of OTP list.\n");
is_empty = true;
}
return is_empty;
}
/*
* iwl_find_otp_image: find EEPROM image in OTP
* finding the OTP block that contains the EEPROM image.
* the last valid block on the link list (the block _before_ the last block)
* is the block we should read and used to configure the device.
* If all the available OTP blocks are full, the last block will be the block
* we should read and used to configure the device.
* only perform this operation if shadow RAM is disabled
*/
static int iwl_find_otp_image(struct iwl_trans *trans,
u16 *validblockaddr)
{
u16 next_link_addr = 0, valid_addr;
__le16 link_value = 0;
int usedblocks = 0;
/* set addressing mode to absolute to traverse the link list */
iwl_set_otp_access_absolute(trans);
/* checking for empty OTP or error */
if (iwl_is_otp_empty(trans))
return -EINVAL;
/*
* start traverse link list
* until reach the max number of OTP blocks
* different devices have different number of OTP blocks
*/
do {
/* save current valid block address
* check for more block on the link list
*/
valid_addr = next_link_addr;
next_link_addr = le16_to_cpu(link_value) * sizeof(u16);
IWL_DEBUG_EEPROM(trans->dev, "OTP blocks %d addr 0x%x\n",
usedblocks, next_link_addr);
if (iwl_read_otp_word(trans, next_link_addr, &link_value))
return -EINVAL;
if (!link_value) {
/*
* reach the end of link list, return success and
* set address point to the starting address
* of the image
*/
*validblockaddr = valid_addr;
/* skip first 2 bytes (link list pointer) */
*validblockaddr += 2;
return 0;
}
/* more in the link list, continue */
usedblocks++;
} while (usedblocks <= trans->cfg->base_params->max_ll_items);
/* OTP has no valid blocks */
IWL_DEBUG_EEPROM(trans->dev, "OTP has no valid blocks\n");
return -EINVAL;
}
/**
* iwl_read_eeprom - read EEPROM contents
*
* Load the EEPROM contents from adapter and return it
* and its size.
*
* NOTE: This routine uses the non-debug IO access functions.
*/
int iwl_read_eeprom(struct iwl_trans *trans, u8 **eeprom, size_t *eeprom_size)
{
__le16 *e;
u32 gp = iwl_read32(trans, CSR_EEPROM_GP);
int sz;
int ret;
u16 addr;
u16 validblockaddr = 0;
u16 cache_addr = 0;
int nvm_is_otp;
if (!eeprom || !eeprom_size)
return -EINVAL;
nvm_is_otp = iwl_nvm_is_otp(trans);
if (nvm_is_otp < 0)
return nvm_is_otp;
sz = trans->cfg->base_params->eeprom_size;
IWL_DEBUG_EEPROM(trans->dev, "NVM size = %d\n", sz);
e = kmalloc(sz, GFP_KERNEL);
if (!e)
return -ENOMEM;
ret = iwl_eeprom_verify_signature(trans, nvm_is_otp);
if (ret < 0) {
IWL_ERR(trans, "EEPROM not found, EEPROM_GP=0x%08x\n", gp);
goto err_free;
}
/* Make sure driver (instead of uCode) is allowed to read EEPROM */
ret = iwl_eeprom_acquire_semaphore(trans);
if (ret < 0) {
IWL_ERR(trans, "Failed to acquire EEPROM semaphore.\n");
goto err_free;
}
if (nvm_is_otp) {
ret = iwl_init_otp_access(trans);
if (ret) {
IWL_ERR(trans, "Failed to initialize OTP access.\n");
goto err_unlock;
}
iwl_write32(trans, CSR_EEPROM_GP,
iwl_read32(trans, CSR_EEPROM_GP) &
~CSR_EEPROM_GP_IF_OWNER_MSK);
iwl_set_bit(trans, CSR_OTP_GP_REG,
CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK |
CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
/* traversing the linked list if no shadow ram supported */
if (!trans->cfg->base_params->shadow_ram_support) {
ret = iwl_find_otp_image(trans, &validblockaddr);
if (ret)
goto err_unlock;
}
for (addr = validblockaddr; addr < validblockaddr + sz;
addr += sizeof(u16)) {
__le16 eeprom_data;
ret = iwl_read_otp_word(trans, addr, &eeprom_data);
if (ret)
goto err_unlock;
e[cache_addr / 2] = eeprom_data;
cache_addr += sizeof(u16);
}
} else {
/* eeprom is an array of 16bit values */
for (addr = 0; addr < sz; addr += sizeof(u16)) {
u32 r;
iwl_write32(trans, CSR_EEPROM_REG,
CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
ret = iwl_poll_bit(trans, CSR_EEPROM_REG,
CSR_EEPROM_REG_READ_VALID_MSK,
CSR_EEPROM_REG_READ_VALID_MSK,
IWL_EEPROM_ACCESS_TIMEOUT);
if (ret < 0) {
IWL_ERR(trans,
"Time out reading EEPROM[%d]\n", addr);
goto err_unlock;
}
r = iwl_read32(trans, CSR_EEPROM_REG);
e[addr / 2] = cpu_to_le16(r >> 16);
}
}
IWL_DEBUG_EEPROM(trans->dev, "NVM Type: %s\n",
nvm_is_otp ? "OTP" : "EEPROM");
iwl_eeprom_release_semaphore(trans);
*eeprom_size = sz;
*eeprom = (u8 *)e;
return 0;
err_unlock:
iwl_eeprom_release_semaphore(trans);
err_free:
kfree(e);
return ret;
}
EXPORT_SYMBOL_GPL(iwl_read_eeprom);
