drivers/infiniband/hw/qib/qib_eeprom.c - kernel/common - Git at Google

 /*
  * Copyright (c) 2012 Intel Corporation. All rights reserved.
  * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
  * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * OpenIB.org BSD license below:
  *
  *     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.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include <linux/delay.h>
 #include <linux/pci.h>
 #include <linux/vmalloc.h>

 #include "qib.h"

 /*
  * Functions specific to the serial EEPROM on cards handled by ib_qib.
  * The actual serail interface code is in qib_twsi.c. This file is a client
  */

 /**
  * qib_eeprom_read - receives bytes from the eeprom via I2C
  * @dd: the qlogic_ib device
  * @eeprom_offset: address to read from
  * @buffer: where to store result
  * @len: number of bytes to receive
  */
 int qib_eeprom_read(struct qib_devdata *dd, u8 eeprom_offset,
 		    void *buff, int len)
 {
 	int ret;

 	ret = mutex_lock_interruptible(&dd->eep_lock);
 	if (!ret) {
 		ret = qib_twsi_reset(dd);
 		if (ret)
 			qib_dev_err(dd, "EEPROM Reset for read failed\n");
 		else
 			ret = qib_twsi_blk_rd(dd, dd->twsi_eeprom_dev,
 					      eeprom_offset, buff, len);
 		mutex_unlock(&dd->eep_lock);
 	}

 	return ret;
 }

 /*
  * Actually update the eeprom, first doing write enable if
  * needed, then restoring write enable state.
  * Must be called with eep_lock held
  */
 static int eeprom_write_with_enable(struct qib_devdata *dd, u8 offset,
 		     const void *buf, int len)
 {
 	int ret, pwen;

 	pwen = dd->f_eeprom_wen(dd, 1);
 	ret = qib_twsi_reset(dd);
 	if (ret)
 		qib_dev_err(dd, "EEPROM Reset for write failed\n");
 	else
 		ret = qib_twsi_blk_wr(dd, dd->twsi_eeprom_dev,
 				      offset, buf, len);
 	dd->f_eeprom_wen(dd, pwen);
 	return ret;
 }

 /**
  * qib_eeprom_write - writes data to the eeprom via I2C
  * @dd: the qlogic_ib device
  * @eeprom_offset: where to place data
  * @buffer: data to write
  * @len: number of bytes to write
  */
 int qib_eeprom_write(struct qib_devdata *dd, u8 eeprom_offset,
 		     const void *buff, int len)
 {
 	int ret;

 	ret = mutex_lock_interruptible(&dd->eep_lock);
 	if (!ret) {
 		ret = eeprom_write_with_enable(dd, eeprom_offset, buff, len);
 		mutex_unlock(&dd->eep_lock);
 	}

 	return ret;
 }

 static u8 flash_csum(struct qib_flash *ifp, int adjust)
 {
 	u8 *ip = (u8 *) ifp;
 	u8 csum = 0, len;

 	/*
 	 * Limit length checksummed to max length of actual data.
 	 * Checksum of erased eeprom will still be bad, but we avoid
 	 * reading past the end of the buffer we were passed.
 	 */
 	len = ifp->if_length;
 	if (len > sizeof(struct qib_flash))
 		len = sizeof(struct qib_flash);
 	while (len--)
 		csum += *ip++;
 	csum -= ifp->if_csum;
 	csum = ~csum;
 	if (adjust)
 		ifp->if_csum = csum;

 	return csum;
 }

 /**
  * qib_get_eeprom_info- get the GUID et al. from the TSWI EEPROM device
  * @dd: the qlogic_ib device
  *
  * We have the capability to use the nguid field, and get
  * the guid from the first chip's flash, to use for all of them.
  */
 void qib_get_eeprom_info(struct qib_devdata *dd)
 {
 	void *buf;
 	struct qib_flash *ifp;
 	__be64 guid;
 	int len, eep_stat;
 	u8 csum, *bguid;
 	int t = dd->unit;
 	struct qib_devdata *dd0 = qib_lookup(0);

 	if (t && dd0->nguid > 1 && t <= dd0->nguid) {
 		u8 oguid;
 		dd->base_guid = dd0->base_guid;
 		bguid = (u8 *) &dd->base_guid;

 		oguid = bguid[7];
 		bguid[7] += t;
 		if (oguid > bguid[7]) {
 			if (bguid[6] == 0xff) {
 				if (bguid[5] == 0xff) {
 					qib_dev_err(dd,
 						"Can't set %s GUID from base, wraps to OUI!\n",
 						qib_get_unit_name(t));
 					dd->base_guid = 0;
 					goto bail;
 				}
 				bguid[5]++;
 			}
 			bguid[6]++;
 		}
 		dd->nguid = 1;
 		goto bail;
 	}

 	/*
 	 * Read full flash, not just currently used part, since it may have
 	 * been written with a newer definition.
 	 * */
 	len = sizeof(struct qib_flash);
 	buf = vmalloc(len);
 	if (!buf) {
 		qib_dev_err(dd,
 			"Couldn't allocate memory to read %u bytes from eeprom for GUID\n",
 			len);
 		goto bail;
 	}

 	/*
 	 * Use "public" eeprom read function, which does locking and
 	 * figures out device. This will migrate to chip-specific.
 	 */
 	eep_stat = qib_eeprom_read(dd, 0, buf, len);

 	if (eep_stat) {
 		qib_dev_err(dd, "Failed reading GUID from eeprom\n");
 		goto done;
 	}
 	ifp = (struct qib_flash *)buf;

 	csum = flash_csum(ifp, 0);
 	if (csum != ifp->if_csum) {
 		qib_devinfo(dd->pcidev,
 			"Bad I2C flash checksum: 0x%x, not 0x%x\n",
 			csum, ifp->if_csum);
 		goto done;
 	}
 	if (*(__be64 *) ifp->if_guid == cpu_to_be64(0) ||
 	    *(__be64 *) ifp->if_guid == ~cpu_to_be64(0)) {
 		qib_dev_err(dd,
 			"Invalid GUID %llx from flash; ignoring\n",
 			*(unsigned long long *) ifp->if_guid);
 		/* don't allow GUID if all 0 or all 1's */
 		goto done;
 	}

 	/* complain, but allow it */
 	if (*(u64 *) ifp->if_guid == 0x100007511000000ULL)
 		qib_devinfo(dd->pcidev,
 			"Warning, GUID %llx is default, probably not correct!\n",
 			*(unsigned long long *) ifp->if_guid);

 	bguid = ifp->if_guid;
 	if (!bguid[0] && !bguid[1] && !bguid[2]) {
 		/*
 		 * Original incorrect GUID format in flash; fix in
 		 * core copy, by shifting up 2 octets; don't need to
 		 * change top octet, since both it and shifted are 0.
 		 */
 		bguid[1] = bguid[3];
 		bguid[2] = bguid[4];
 		bguid[3] = 0;
 		bguid[4] = 0;
 		guid = *(__be64 *) ifp->if_guid;
 	} else
 		guid = *(__be64 *) ifp->if_guid;
 	dd->base_guid = guid;
 	dd->nguid = ifp->if_numguid;
 	/*
 	 * Things are slightly complicated by the desire to transparently
 	 * support both the Pathscale 10-digit serial number and the QLogic
 	 * 13-character version.
 	 */
 	if ((ifp->if_fversion > 1) && ifp->if_sprefix[0] &&
 	    ((u8 *) ifp->if_sprefix)[0] != 0xFF) {
 		char *snp = dd->serial;

 		/*
 		 * This board has a Serial-prefix, which is stored
 		 * elsewhere for backward-compatibility.
 		 */
 		memcpy(snp, ifp->if_sprefix, sizeof ifp->if_sprefix);
 		snp[sizeof ifp->if_sprefix] = '\0';
 		len = strlen(snp);
 		snp += len;
 		len = (sizeof dd->serial) - len;
 		if (len > sizeof ifp->if_serial)
 			len = sizeof ifp->if_serial;
 		memcpy(snp, ifp->if_serial, len);
 	} else
 		memcpy(dd->serial, ifp->if_serial,
 		       sizeof ifp->if_serial);
 	if (!strstr(ifp->if_comment, "Tested successfully"))
 		qib_dev_err(dd,
 			"Board SN %s did not pass functional test: %s\n",
 			dd->serial, ifp->if_comment);

 	memcpy(&dd->eep_st_errs, &ifp->if_errcntp, QIB_EEP_LOG_CNT);
 	/*
 	 * Power-on (actually "active") hours are kept as little-endian value
 	 * in EEPROM, but as seconds in a (possibly as small as 24-bit)
 	 * atomic_t while running.
 	 */
 	atomic_set(&dd->active_time, 0);
 	dd->eep_hrs = ifp->if_powerhour[0] | (ifp->if_powerhour[1] << 8);

 done:
 	vfree(buf);

 bail:;
 }

 /**
  * qib_update_eeprom_log - copy active-time and error counters to eeprom
  * @dd: the qlogic_ib device
  *
  * Although the time is kept as seconds in the qib_devdata struct, it is
  * rounded to hours for re-write, as we have only 16 bits in EEPROM.
  * First-cut code reads whole (expected) struct qib_flash, modifies,
  * re-writes. Future direction: read/write only what we need, assuming
  * that the EEPROM had to have been "good enough" for driver init, and
  * if not, we aren't making it worse.
  *
  */
 int qib_update_eeprom_log(struct qib_devdata *dd)
 {
 	void *buf;
 	struct qib_flash *ifp;
 	int len, hi_water;
 	uint32_t new_time, new_hrs;
 	u8 csum;
 	int ret, idx;
 	unsigned long flags;

 	/* first, check if we actually need to do anything. */
 	ret = 0;
 	for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
 		if (dd->eep_st_new_errs[idx]) {
 			ret = 1;
 			break;
 		}
 	}
 	new_time = atomic_read(&dd->active_time);

 	if (ret == 0 && new_time < 3600)
 		goto bail;

 	/*
 	 * The quick-check above determined that there is something worthy
 	 * of logging, so get current contents and do a more detailed idea.
 	 * read full flash, not just currently used part, since it may have
 	 * been written with a newer definition
 	 */
 	len = sizeof(struct qib_flash);
 	buf = vmalloc(len);
 	ret = 1;
 	if (!buf) {
 		qib_dev_err(dd,
 			"Couldn't allocate memory to read %u bytes from eeprom for logging\n",
 			len);
 		goto bail;
 	}

 	/* Grab semaphore and read current EEPROM. If we get an
 	 * error, let go, but if not, keep it until we finish write.
 	 */
 	ret = mutex_lock_interruptible(&dd->eep_lock);
 	if (ret) {
 		qib_dev_err(dd, "Unable to acquire EEPROM for logging\n");
 		goto free_bail;
 	}
 	ret = qib_twsi_blk_rd(dd, dd->twsi_eeprom_dev, 0, buf, len);
 	if (ret) {
 		mutex_unlock(&dd->eep_lock);
 		qib_dev_err(dd, "Unable read EEPROM for logging\n");
 		goto free_bail;
 	}
 	ifp = (struct qib_flash *)buf;

 	csum = flash_csum(ifp, 0);
 	if (csum != ifp->if_csum) {
 		mutex_unlock(&dd->eep_lock);
 		qib_dev_err(dd, "EEPROM cks err (0x%02X, S/B 0x%02X)\n",
 			    csum, ifp->if_csum);
 		ret = 1;
 		goto free_bail;
 	}
 	hi_water = 0;
 	spin_lock_irqsave(&dd->eep_st_lock, flags);
 	for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
 		int new_val = dd->eep_st_new_errs[idx];
 		if (new_val) {
 			/*
 			 * If we have seen any errors, add to EEPROM values
 			 * We need to saturate at 0xFF (255) and we also
 			 * would need to adjust the checksum if we were
 			 * trying to minimize EEPROM traffic
 			 * Note that we add to actual current count in EEPROM,
 			 * in case it was altered while we were running.
 			 */
 			new_val += ifp->if_errcntp[idx];
 			if (new_val > 0xFF)
 				new_val = 0xFF;
 			if (ifp->if_errcntp[idx] != new_val) {
 				ifp->if_errcntp[idx] = new_val;
 				hi_water = offsetof(struct qib_flash,
 						    if_errcntp) + idx;
 			}
 			/*
 			 * update our shadow (used to minimize EEPROM
 			 * traffic), to match what we are about to write.
 			 */
 			dd->eep_st_errs[idx] = new_val;
 			dd->eep_st_new_errs[idx] = 0;
 		}
 	}
 	/*
 	 * Now update active-time. We would like to round to the nearest hour
 	 * but unless atomic_t are sure to be proper signed ints we cannot,
 	 * because we need to account for what we "transfer" to EEPROM and
 	 * if we log an hour at 31 minutes, then we would need to set
 	 * active_time to -29 to accurately count the _next_ hour.
 	 */
 	if (new_time >= 3600) {
 		new_hrs = new_time / 3600;
 		atomic_sub((new_hrs * 3600), &dd->active_time);
 		new_hrs += dd->eep_hrs;
 		if (new_hrs > 0xFFFF)
 			new_hrs = 0xFFFF;
 		dd->eep_hrs = new_hrs;
 		if ((new_hrs & 0xFF) != ifp->if_powerhour[0]) {
 			ifp->if_powerhour[0] = new_hrs & 0xFF;
 			hi_water = offsetof(struct qib_flash, if_powerhour);
 		}
 		if ((new_hrs >> 8) != ifp->if_powerhour[1]) {
 			ifp->if_powerhour[1] = new_hrs >> 8;
 			hi_water = offsetof(struct qib_flash, if_powerhour) + 1;
 		}
 	}
 	/*
 	 * There is a tiny possibility that we could somehow fail to write
 	 * the EEPROM after updating our shadows, but problems from holding
 	 * the spinlock too long are a much bigger issue.
 	 */
 	spin_unlock_irqrestore(&dd->eep_st_lock, flags);
 	if (hi_water) {
 		/* we made some change to the data, uopdate cksum and write */
 		csum = flash_csum(ifp, 1);
 		ret = eeprom_write_with_enable(dd, 0, buf, hi_water + 1);
 	}
 	mutex_unlock(&dd->eep_lock);
 	if (ret)
 		qib_dev_err(dd, "Failed updating EEPROM\n");

 free_bail:
 	vfree(buf);
 bail:
 	return ret;
 }

 /**
  * qib_inc_eeprom_err - increment one of the four error counters
  * that are logged to EEPROM.
  * @dd: the qlogic_ib device
  * @eidx: 0..3, the counter to increment
  * @incr: how much to add
  *
  * Each counter is 8-bits, and saturates at 255 (0xFF). They
  * are copied to the EEPROM (aka flash) whenever qib_update_eeprom_log()
  * is called, but it can only be called in a context that allows sleep.
  * This function can be called even at interrupt level.
  */
 void qib_inc_eeprom_err(struct qib_devdata *dd, u32 eidx, u32 incr)
 {
 	uint new_val;
 	unsigned long flags;

 	spin_lock_irqsave(&dd->eep_st_lock, flags);
 	new_val = dd->eep_st_new_errs[eidx] + incr;
 	if (new_val > 255)
 		new_val = 255;
 	dd->eep_st_new_errs[eidx] = new_val;
 	spin_unlock_irqrestore(&dd->eep_st_lock, flags);
 }
	/*
	* Copyright (c) 2012 Intel Corporation. All rights reserved.
	* Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
	* Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* OpenIB.org BSD license below:
	*
	* 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.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include <linux/delay.h>
	#include <linux/pci.h>
	#include <linux/vmalloc.h>

	#include "qib.h"

	/*
	* Functions specific to the serial EEPROM on cards handled by ib_qib.
	* The actual serail interface code is in qib_twsi.c. This file is a client
	*/

	/**
	* qib_eeprom_read - receives bytes from the eeprom via I2C
	* @dd: the qlogic_ib device
	* @eeprom_offset: address to read from
	* @buffer: where to store result
	* @len: number of bytes to receive
	*/
	int qib_eeprom_read(struct qib_devdata *dd, u8 eeprom_offset,
	void *buff, int len)
	{
	int ret;

	ret = mutex_lock_interruptible(&dd->eep_lock);
	if (!ret) {
	ret = qib_twsi_reset(dd);
	if (ret)
	qib_dev_err(dd, "EEPROM Reset for read failed\n");
	else
	ret = qib_twsi_blk_rd(dd, dd->twsi_eeprom_dev,
	eeprom_offset, buff, len);
	mutex_unlock(&dd->eep_lock);
	}

	return ret;
	}

	/*
	* Actually update the eeprom, first doing write enable if
	* needed, then restoring write enable state.
	* Must be called with eep_lock held
	*/
	static int eeprom_write_with_enable(struct qib_devdata *dd, u8 offset,
	const void *buf, int len)
	{
	int ret, pwen;

	pwen = dd->f_eeprom_wen(dd, 1);
	ret = qib_twsi_reset(dd);
	if (ret)
	qib_dev_err(dd, "EEPROM Reset for write failed\n");
	else
	ret = qib_twsi_blk_wr(dd, dd->twsi_eeprom_dev,
	offset, buf, len);
	dd->f_eeprom_wen(dd, pwen);
	return ret;
	}

	/**
	* qib_eeprom_write - writes data to the eeprom via I2C
	* @dd: the qlogic_ib device
	* @eeprom_offset: where to place data
	* @buffer: data to write
	* @len: number of bytes to write
	*/
	int qib_eeprom_write(struct qib_devdata *dd, u8 eeprom_offset,
	const void *buff, int len)
	{
	int ret;

	ret = mutex_lock_interruptible(&dd->eep_lock);
	if (!ret) {
	ret = eeprom_write_with_enable(dd, eeprom_offset, buff, len);
	mutex_unlock(&dd->eep_lock);
	}

	return ret;
	}

	static u8 flash_csum(struct qib_flash *ifp, int adjust)
	{
	u8 ip = (u8 ) ifp;
	u8 csum = 0, len;

	/*
	* Limit length checksummed to max length of actual data.
	* Checksum of erased eeprom will still be bad, but we avoid
	* reading past the end of the buffer we were passed.
	*/
	len = ifp->if_length;
	if (len > sizeof(struct qib_flash))
	len = sizeof(struct qib_flash);
	while (len--)
	csum += *ip++;
	csum -= ifp->if_csum;
	csum = ~csum;
	if (adjust)
	ifp->if_csum = csum;

	return csum;
	}

	/**
	* qib_get_eeprom_info- get the GUID et al. from the TSWI EEPROM device
	* @dd: the qlogic_ib device
	*
	* We have the capability to use the nguid field, and get
	* the guid from the first chip's flash, to use for all of them.
	*/
	void qib_get_eeprom_info(struct qib_devdata *dd)
	{
	void *buf;
	struct qib_flash *ifp;
	__be64 guid;
	int len, eep_stat;
	u8 csum, *bguid;
	int t = dd->unit;
	struct qib_devdata *dd0 = qib_lookup(0);

	if (t && dd0->nguid > 1 && t <= dd0->nguid) {
	u8 oguid;
	dd->base_guid = dd0->base_guid;
	bguid = (u8 *) &dd->base_guid;

	oguid = bguid[7];
	bguid[7] += t;
	if (oguid > bguid[7]) {
	if (bguid[6] == 0xff) {
	if (bguid[5] == 0xff) {
	qib_dev_err(dd,
	"Can't set %s GUID from base, wraps to OUI!\n",
	qib_get_unit_name(t));
	dd->base_guid = 0;
	goto bail;
	}
	bguid[5]++;
	}
	bguid[6]++;
	}
	dd->nguid = 1;
	goto bail;
	}

	/*
	* Read full flash, not just currently used part, since it may have
	* been written with a newer definition.
	* */
	len = sizeof(struct qib_flash);
	buf = vmalloc(len);
	if (!buf) {
	qib_dev_err(dd,
	"Couldn't allocate memory to read %u bytes from eeprom for GUID\n",
	len);
	goto bail;
	}

	/*
	* Use "public" eeprom read function, which does locking and
	* figures out device. This will migrate to chip-specific.
	*/
	eep_stat = qib_eeprom_read(dd, 0, buf, len);

	if (eep_stat) {
	qib_dev_err(dd, "Failed reading GUID from eeprom\n");
	goto done;
	}
	ifp = (struct qib_flash *)buf;

	csum = flash_csum(ifp, 0);
	if (csum != ifp->if_csum) {
	qib_devinfo(dd->pcidev,
	"Bad I2C flash checksum: 0x%x, not 0x%x\n",
	csum, ifp->if_csum);
	goto done;
	}
	if ((__be64 ) ifp->if_guid == cpu_to_be64(0) \|\|
	(__be64 ) ifp->if_guid == ~cpu_to_be64(0)) {
	qib_dev_err(dd,
	"Invalid GUID %llx from flash; ignoring\n",
	(unsigned long long ) ifp->if_guid);
	/* don't allow GUID if all 0 or all 1's */
	goto done;
	}

	/* complain, but allow it */
	if ((u64 ) ifp->if_guid == 0x100007511000000ULL)
	qib_devinfo(dd->pcidev,
	"Warning, GUID %llx is default, probably not correct!\n",
	(unsigned long long ) ifp->if_guid);

	bguid = ifp->if_guid;
	if (!bguid[0] && !bguid[1] && !bguid[2]) {
	/*
	* Original incorrect GUID format in flash; fix in
	* core copy, by shifting up 2 octets; don't need to
	* change top octet, since both it and shifted are 0.
	*/
	bguid[1] = bguid[3];
	bguid[2] = bguid[4];
	bguid[3] = 0;
	bguid[4] = 0;
	guid = (__be64 ) ifp->if_guid;
	} else
	guid = (__be64 ) ifp->if_guid;
	dd->base_guid = guid;
	dd->nguid = ifp->if_numguid;
	/*
	* Things are slightly complicated by the desire to transparently
	* support both the Pathscale 10-digit serial number and the QLogic
	* 13-character version.
	*/
	if ((ifp->if_fversion > 1) && ifp->if_sprefix[0] &&
	((u8 *) ifp->if_sprefix)[0] != 0xFF) {
	char *snp = dd->serial;

	/*
	* This board has a Serial-prefix, which is stored
	* elsewhere for backward-compatibility.
	*/
	memcpy(snp, ifp->if_sprefix, sizeof ifp->if_sprefix);
	snp[sizeof ifp->if_sprefix] = '\0';
	len = strlen(snp);
	snp += len;
	len = (sizeof dd->serial) - len;
	if (len > sizeof ifp->if_serial)
	len = sizeof ifp->if_serial;
	memcpy(snp, ifp->if_serial, len);
	} else
	memcpy(dd->serial, ifp->if_serial,
	sizeof ifp->if_serial);
	if (!strstr(ifp->if_comment, "Tested successfully"))
	qib_dev_err(dd,
	"Board SN %s did not pass functional test: %s\n",
	dd->serial, ifp->if_comment);

	memcpy(&dd->eep_st_errs, &ifp->if_errcntp, QIB_EEP_LOG_CNT);
	/*
	* Power-on (actually "active") hours are kept as little-endian value
	* in EEPROM, but as seconds in a (possibly as small as 24-bit)
	* atomic_t while running.
	*/
	atomic_set(&dd->active_time, 0);
	dd->eep_hrs = ifp->if_powerhour[0] \| (ifp->if_powerhour[1] << 8);

	done:
	vfree(buf);

	bail:;
	}

	/**
	* qib_update_eeprom_log - copy active-time and error counters to eeprom
	* @dd: the qlogic_ib device
	*
	* Although the time is kept as seconds in the qib_devdata struct, it is
	* rounded to hours for re-write, as we have only 16 bits in EEPROM.
	* First-cut code reads whole (expected) struct qib_flash, modifies,
	* re-writes. Future direction: read/write only what we need, assuming
	* that the EEPROM had to have been "good enough" for driver init, and
	* if not, we aren't making it worse.
	*
	*/
	int qib_update_eeprom_log(struct qib_devdata *dd)
	{
	void *buf;
	struct qib_flash *ifp;
	int len, hi_water;
	uint32_t new_time, new_hrs;
	u8 csum;
	int ret, idx;
	unsigned long flags;

	/* first, check if we actually need to do anything. */
	ret = 0;
	for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
	if (dd->eep_st_new_errs[idx]) {
	ret = 1;
	break;
	}
	}
	new_time = atomic_read(&dd->active_time);

	if (ret == 0 && new_time < 3600)
	goto bail;

	/*
	* The quick-check above determined that there is something worthy
	* of logging, so get current contents and do a more detailed idea.
	* read full flash, not just currently used part, since it may have
	* been written with a newer definition
	*/
	len = sizeof(struct qib_flash);
	buf = vmalloc(len);
	ret = 1;
	if (!buf) {
	qib_dev_err(dd,
	"Couldn't allocate memory to read %u bytes from eeprom for logging\n",
	len);
	goto bail;
	}

	/* Grab semaphore and read current EEPROM. If we get an
	* error, let go, but if not, keep it until we finish write.
	*/
	ret = mutex_lock_interruptible(&dd->eep_lock);
	if (ret) {
	qib_dev_err(dd, "Unable to acquire EEPROM for logging\n");
	goto free_bail;
	}
	ret = qib_twsi_blk_rd(dd, dd->twsi_eeprom_dev, 0, buf, len);
	if (ret) {
	mutex_unlock(&dd->eep_lock);
	qib_dev_err(dd, "Unable read EEPROM for logging\n");
	goto free_bail;
	}
	ifp = (struct qib_flash *)buf;

	csum = flash_csum(ifp, 0);
	if (csum != ifp->if_csum) {
	mutex_unlock(&dd->eep_lock);
	qib_dev_err(dd, "EEPROM cks err (0x%02X, S/B 0x%02X)\n",
	csum, ifp->if_csum);
	ret = 1;
	goto free_bail;
	}
	hi_water = 0;
	spin_lock_irqsave(&dd->eep_st_lock, flags);
	for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
	int new_val = dd->eep_st_new_errs[idx];
	if (new_val) {
	/*
	* If we have seen any errors, add to EEPROM values
	* We need to saturate at 0xFF (255) and we also
	* would need to adjust the checksum if we were
	* trying to minimize EEPROM traffic
	* Note that we add to actual current count in EEPROM,
	* in case it was altered while we were running.
	*/
	new_val += ifp->if_errcntp[idx];
	if (new_val > 0xFF)
	new_val = 0xFF;
	if (ifp->if_errcntp[idx] != new_val) {
	ifp->if_errcntp[idx] = new_val;
	hi_water = offsetof(struct qib_flash,
	if_errcntp) + idx;
	}
	/*
	* update our shadow (used to minimize EEPROM
	* traffic), to match what we are about to write.
	*/
	dd->eep_st_errs[idx] = new_val;
	dd->eep_st_new_errs[idx] = 0;
	}
	}
	/*
	* Now update active-time. We would like to round to the nearest hour
	* but unless atomic_t are sure to be proper signed ints we cannot,
	* because we need to account for what we "transfer" to EEPROM and
	* if we log an hour at 31 minutes, then we would need to set
	* active_time to -29 to accurately count the _next_ hour.
	*/
	if (new_time >= 3600) {
	new_hrs = new_time / 3600;
	atomic_sub((new_hrs * 3600), &dd->active_time);
	new_hrs += dd->eep_hrs;
	if (new_hrs > 0xFFFF)
	new_hrs = 0xFFFF;
	dd->eep_hrs = new_hrs;
	if ((new_hrs & 0xFF) != ifp->if_powerhour[0]) {
	ifp->if_powerhour[0] = new_hrs & 0xFF;
	hi_water = offsetof(struct qib_flash, if_powerhour);
	}
	if ((new_hrs >> 8) != ifp->if_powerhour[1]) {
	ifp->if_powerhour[1] = new_hrs >> 8;
	hi_water = offsetof(struct qib_flash, if_powerhour) + 1;
	}
	}
	/*
	* There is a tiny possibility that we could somehow fail to write
	* the EEPROM after updating our shadows, but problems from holding
	* the spinlock too long are a much bigger issue.
	*/
	spin_unlock_irqrestore(&dd->eep_st_lock, flags);
	if (hi_water) {
	/* we made some change to the data, uopdate cksum and write */
	csum = flash_csum(ifp, 1);
	ret = eeprom_write_with_enable(dd, 0, buf, hi_water + 1);
	}
	mutex_unlock(&dd->eep_lock);
	if (ret)
	qib_dev_err(dd, "Failed updating EEPROM\n");

	free_bail:
	vfree(buf);
	bail:
	return ret;
	}

	/**
	* qib_inc_eeprom_err - increment one of the four error counters
	* that are logged to EEPROM.
	* @dd: the qlogic_ib device
	* @eidx: 0..3, the counter to increment
	* @incr: how much to add
	*
	* Each counter is 8-bits, and saturates at 255 (0xFF). They
	* are copied to the EEPROM (aka flash) whenever qib_update_eeprom_log()
	* is called, but it can only be called in a context that allows sleep.
	* This function can be called even at interrupt level.
	*/
	void qib_inc_eeprom_err(struct qib_devdata *dd, u32 eidx, u32 incr)
	{
	uint new_val;
	unsigned long flags;

	spin_lock_irqsave(&dd->eep_st_lock, flags);
	new_val = dd->eep_st_new_errs[eidx] + incr;
	if (new_val > 255)
	new_val = 255;
	dd->eep_st_new_errs[eidx] = new_val;
	spin_unlock_irqrestore(&dd->eep_st_lock, flags);
	}