/
scsi_transport_spi.c
1530 lines (1309 loc) · 41.3 KB
/
scsi_transport_spi.c
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/*
* Parallel SCSI (SPI) transport specific attributes exported to sysfs.
*
* Copyright (c) 2003 Silicon Graphics, Inc. All rights reserved.
* Copyright (c) 2004, 2005 James Bottomley <James.Bottomley@SteelEye.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/workqueue.h>
#include <linux/blkdev.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <scsi/scsi.h>
#include "scsi_priv.h"
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_spi.h>
#define SPI_NUM_ATTRS 14 /* increase this if you add attributes */
#define SPI_OTHER_ATTRS 1 /* Increase this if you add "always
* on" attributes */
#define SPI_HOST_ATTRS 1
#define SPI_MAX_ECHO_BUFFER_SIZE 4096
#define DV_LOOPS 3
#define DV_TIMEOUT (10*HZ)
#define DV_RETRIES 3 /* should only need at most
* two cc/ua clears */
/* Private data accessors (keep these out of the header file) */
#define spi_dv_in_progress(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_in_progress)
#define spi_dv_mutex(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_mutex)
struct spi_internal {
struct scsi_transport_template t;
struct spi_function_template *f;
};
#define to_spi_internal(tmpl) container_of(tmpl, struct spi_internal, t)
static const int ppr_to_ps[] = {
/* The PPR values 0-6 are reserved, fill them in when
* the committee defines them */
-1, /* 0x00 */
-1, /* 0x01 */
-1, /* 0x02 */
-1, /* 0x03 */
-1, /* 0x04 */
-1, /* 0x05 */
-1, /* 0x06 */
3125, /* 0x07 */
6250, /* 0x08 */
12500, /* 0x09 */
25000, /* 0x0a */
30300, /* 0x0b */
50000, /* 0x0c */
};
/* The PPR values at which you calculate the period in ns by multiplying
* by 4 */
#define SPI_STATIC_PPR 0x0c
static int sprint_frac(char *dest, int value, int denom)
{
int frac = value % denom;
int result = sprintf(dest, "%d", value / denom);
if (frac == 0)
return result;
dest[result++] = '.';
do {
denom /= 10;
sprintf(dest + result, "%d", frac / denom);
result++;
frac %= denom;
} while (frac);
dest[result++] = '\0';
return result;
}
static int spi_execute(struct scsi_device *sdev, const void *cmd,
enum dma_data_direction dir,
void *buffer, unsigned bufflen,
struct scsi_sense_hdr *sshdr)
{
int i, result;
unsigned char sense[SCSI_SENSE_BUFFERSIZE];
for(i = 0; i < DV_RETRIES; i++) {
result = scsi_execute(sdev, cmd, dir, buffer, bufflen,
sense, DV_TIMEOUT, /* retries */ 1,
REQ_FAILFAST);
if (result & DRIVER_SENSE) {
struct scsi_sense_hdr sshdr_tmp;
if (!sshdr)
sshdr = &sshdr_tmp;
if (scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE,
sshdr)
&& sshdr->sense_key == UNIT_ATTENTION)
continue;
}
break;
}
return result;
}
static struct {
enum spi_signal_type value;
char *name;
} signal_types[] = {
{ SPI_SIGNAL_UNKNOWN, "unknown" },
{ SPI_SIGNAL_SE, "SE" },
{ SPI_SIGNAL_LVD, "LVD" },
{ SPI_SIGNAL_HVD, "HVD" },
};
static inline const char *spi_signal_to_string(enum spi_signal_type type)
{
int i;
for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
if (type == signal_types[i].value)
return signal_types[i].name;
}
return NULL;
}
static inline enum spi_signal_type spi_signal_to_value(const char *name)
{
int i, len;
for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
len = strlen(signal_types[i].name);
if (strncmp(name, signal_types[i].name, len) == 0 &&
(name[len] == '\n' || name[len] == '\0'))
return signal_types[i].value;
}
return SPI_SIGNAL_UNKNOWN;
}
static int spi_host_setup(struct transport_container *tc, struct device *dev,
struct device *cdev)
{
struct Scsi_Host *shost = dev_to_shost(dev);
spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
return 0;
}
static int spi_host_configure(struct transport_container *tc,
struct device *dev,
struct device *cdev);
static DECLARE_TRANSPORT_CLASS(spi_host_class,
"spi_host",
spi_host_setup,
NULL,
spi_host_configure);
static int spi_host_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
if (!scsi_is_host_device(dev))
return 0;
shost = dev_to_shost(dev);
if (!shost->transportt || shost->transportt->host_attrs.ac.class
!= &spi_host_class.class)
return 0;
return &shost->transportt->host_attrs.ac == cont;
}
static int spi_target_configure(struct transport_container *tc,
struct device *dev,
struct device *cdev);
static int spi_device_configure(struct transport_container *tc,
struct device *dev,
struct device *cdev)
{
struct scsi_device *sdev = to_scsi_device(dev);
struct scsi_target *starget = sdev->sdev_target;
/* Populate the target capability fields with the values
* gleaned from the device inquiry */
spi_support_sync(starget) = scsi_device_sync(sdev);
spi_support_wide(starget) = scsi_device_wide(sdev);
spi_support_dt(starget) = scsi_device_dt(sdev);
spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
spi_support_ius(starget) = scsi_device_ius(sdev);
spi_support_qas(starget) = scsi_device_qas(sdev);
return 0;
}
static int spi_setup_transport_attrs(struct transport_container *tc,
struct device *dev,
struct device *cdev)
{
struct scsi_target *starget = to_scsi_target(dev);
spi_period(starget) = -1; /* illegal value */
spi_min_period(starget) = 0;
spi_offset(starget) = 0; /* async */
spi_max_offset(starget) = 255;
spi_width(starget) = 0; /* narrow */
spi_max_width(starget) = 1;
spi_iu(starget) = 0; /* no IU */
spi_dt(starget) = 0; /* ST */
spi_qas(starget) = 0;
spi_wr_flow(starget) = 0;
spi_rd_strm(starget) = 0;
spi_rti(starget) = 0;
spi_pcomp_en(starget) = 0;
spi_hold_mcs(starget) = 0;
spi_dv_pending(starget) = 0;
spi_dv_in_progress(starget) = 0;
spi_initial_dv(starget) = 0;
mutex_init(&spi_dv_mutex(starget));
return 0;
}
#define spi_transport_show_simple(field, format_string) \
\
static ssize_t \
show_spi_transport_##field(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct scsi_target *starget = transport_class_to_starget(dev); \
struct spi_transport_attrs *tp; \
\
tp = (struct spi_transport_attrs *)&starget->starget_data; \
return snprintf(buf, 20, format_string, tp->field); \
}
#define spi_transport_store_simple(field, format_string) \
\
static ssize_t \
store_spi_transport_##field(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
int val; \
struct scsi_target *starget = transport_class_to_starget(dev); \
struct spi_transport_attrs *tp; \
\
tp = (struct spi_transport_attrs *)&starget->starget_data; \
val = simple_strtoul(buf, NULL, 0); \
tp->field = val; \
return count; \
}
#define spi_transport_show_function(field, format_string) \
\
static ssize_t \
show_spi_transport_##field(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct scsi_target *starget = transport_class_to_starget(dev); \
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); \
struct spi_transport_attrs *tp; \
struct spi_internal *i = to_spi_internal(shost->transportt); \
tp = (struct spi_transport_attrs *)&starget->starget_data; \
if (i->f->get_##field) \
i->f->get_##field(starget); \
return snprintf(buf, 20, format_string, tp->field); \
}
#define spi_transport_store_function(field, format_string) \
static ssize_t \
store_spi_transport_##field(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
int val; \
struct scsi_target *starget = transport_class_to_starget(dev); \
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); \
struct spi_internal *i = to_spi_internal(shost->transportt); \
\
if (!i->f->set_##field) \
return -EINVAL; \
val = simple_strtoul(buf, NULL, 0); \
i->f->set_##field(starget, val); \
return count; \
}
#define spi_transport_store_max(field, format_string) \
static ssize_t \
store_spi_transport_##field(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
int val; \
struct scsi_target *starget = transport_class_to_starget(dev); \
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); \
struct spi_internal *i = to_spi_internal(shost->transportt); \
struct spi_transport_attrs *tp \
= (struct spi_transport_attrs *)&starget->starget_data; \
\
if (i->f->set_##field) \
return -EINVAL; \
val = simple_strtoul(buf, NULL, 0); \
if (val > tp->max_##field) \
val = tp->max_##field; \
i->f->set_##field(starget, val); \
return count; \
}
#define spi_transport_rd_attr(field, format_string) \
spi_transport_show_function(field, format_string) \
spi_transport_store_function(field, format_string) \
static DEVICE_ATTR(field, S_IRUGO, \
show_spi_transport_##field, \
store_spi_transport_##field);
#define spi_transport_simple_attr(field, format_string) \
spi_transport_show_simple(field, format_string) \
spi_transport_store_simple(field, format_string) \
static DEVICE_ATTR(field, S_IRUGO, \
show_spi_transport_##field, \
store_spi_transport_##field);
#define spi_transport_max_attr(field, format_string) \
spi_transport_show_function(field, format_string) \
spi_transport_store_max(field, format_string) \
spi_transport_simple_attr(max_##field, format_string) \
static DEVICE_ATTR(field, S_IRUGO, \
show_spi_transport_##field, \
store_spi_transport_##field);
/* The Parallel SCSI Tranport Attributes: */
spi_transport_max_attr(offset, "%d\n");
spi_transport_max_attr(width, "%d\n");
spi_transport_rd_attr(iu, "%d\n");
spi_transport_rd_attr(dt, "%d\n");
spi_transport_rd_attr(qas, "%d\n");
spi_transport_rd_attr(wr_flow, "%d\n");
spi_transport_rd_attr(rd_strm, "%d\n");
spi_transport_rd_attr(rti, "%d\n");
spi_transport_rd_attr(pcomp_en, "%d\n");
spi_transport_rd_attr(hold_mcs, "%d\n");
/* we only care about the first child device so we return 1 */
static int child_iter(struct device *dev, void *data)
{
struct scsi_device *sdev = to_scsi_device(dev);
spi_dv_device(sdev);
return 1;
}
static ssize_t
store_spi_revalidate(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct scsi_target *starget = transport_class_to_starget(dev);
device_for_each_child(&starget->dev, NULL, child_iter);
return count;
}
static DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
/* Translate the period into ns according to the current spec
* for SDTR/PPR messages */
static int period_to_str(char *buf, int period)
{
int len, picosec;
if (period < 0 || period > 0xff) {
picosec = -1;
} else if (period <= SPI_STATIC_PPR) {
picosec = ppr_to_ps[period];
} else {
picosec = period * 4000;
}
if (picosec == -1) {
len = sprintf(buf, "reserved");
} else {
len = sprint_frac(buf, picosec, 1000);
}
return len;
}
static ssize_t
show_spi_transport_period_helper(char *buf, int period)
{
int len = period_to_str(buf, period);
buf[len++] = '\n';
buf[len] = '\0';
return len;
}
static ssize_t
store_spi_transport_period_helper(struct device *dev, const char *buf,
size_t count, int *periodp)
{
int j, picosec, period = -1;
char *endp;
picosec = simple_strtoul(buf, &endp, 10) * 1000;
if (*endp == '.') {
int mult = 100;
do {
endp++;
if (!isdigit(*endp))
break;
picosec += (*endp - '0') * mult;
mult /= 10;
} while (mult > 0);
}
for (j = 0; j <= SPI_STATIC_PPR; j++) {
if (ppr_to_ps[j] < picosec)
continue;
period = j;
break;
}
if (period == -1)
period = picosec / 4000;
if (period > 0xff)
period = 0xff;
*periodp = period;
return count;
}
static ssize_t
show_spi_transport_period(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct scsi_target *starget = transport_class_to_starget(dev);
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
struct spi_internal *i = to_spi_internal(shost->transportt);
struct spi_transport_attrs *tp =
(struct spi_transport_attrs *)&starget->starget_data;
if (i->f->get_period)
i->f->get_period(starget);
return show_spi_transport_period_helper(buf, tp->period);
}
static ssize_t
store_spi_transport_period(struct device *cdev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct scsi_target *starget = transport_class_to_starget(cdev);
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
struct spi_internal *i = to_spi_internal(shost->transportt);
struct spi_transport_attrs *tp =
(struct spi_transport_attrs *)&starget->starget_data;
int period, retval;
if (!i->f->set_period)
return -EINVAL;
retval = store_spi_transport_period_helper(cdev, buf, count, &period);
if (period < tp->min_period)
period = tp->min_period;
i->f->set_period(starget, period);
return retval;
}
static DEVICE_ATTR(period, S_IRUGO,
show_spi_transport_period,
store_spi_transport_period);
static ssize_t
show_spi_transport_min_period(struct device *cdev,
struct device_attribute *attr, char *buf)
{
struct scsi_target *starget = transport_class_to_starget(cdev);
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
struct spi_internal *i = to_spi_internal(shost->transportt);
struct spi_transport_attrs *tp =
(struct spi_transport_attrs *)&starget->starget_data;
if (!i->f->set_period)
return -EINVAL;
return show_spi_transport_period_helper(buf, tp->min_period);
}
static ssize_t
store_spi_transport_min_period(struct device *cdev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct scsi_target *starget = transport_class_to_starget(cdev);
struct spi_transport_attrs *tp =
(struct spi_transport_attrs *)&starget->starget_data;
return store_spi_transport_period_helper(cdev, buf, count,
&tp->min_period);
}
static DEVICE_ATTR(min_period, S_IRUGO,
show_spi_transport_min_period,
store_spi_transport_min_period);
static ssize_t show_spi_host_signalling(struct device *cdev,
struct device_attribute *attr,
char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct spi_internal *i = to_spi_internal(shost->transportt);
if (i->f->get_signalling)
i->f->get_signalling(shost);
return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
}
static ssize_t store_spi_host_signalling(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct Scsi_Host *shost = transport_class_to_shost(dev);
struct spi_internal *i = to_spi_internal(shost->transportt);
enum spi_signal_type type = spi_signal_to_value(buf);
if (!i->f->set_signalling)
return -EINVAL;
if (type != SPI_SIGNAL_UNKNOWN)
i->f->set_signalling(shost, type);
return count;
}
static DEVICE_ATTR(signalling, S_IRUGO,
show_spi_host_signalling,
store_spi_host_signalling);
#define DV_SET(x, y) \
if(i->f->set_##x) \
i->f->set_##x(sdev->sdev_target, y)
enum spi_compare_returns {
SPI_COMPARE_SUCCESS,
SPI_COMPARE_FAILURE,
SPI_COMPARE_SKIP_TEST,
};
/* This is for read/write Domain Validation: If the device supports
* an echo buffer, we do read/write tests to it */
static enum spi_compare_returns
spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
u8 *ptr, const int retries)
{
int len = ptr - buffer;
int j, k, r, result;
unsigned int pattern = 0x0000ffff;
struct scsi_sense_hdr sshdr;
const char spi_write_buffer[] = {
WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
};
const char spi_read_buffer[] = {
READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
};
/* set up the pattern buffer. Doesn't matter if we spill
* slightly beyond since that's where the read buffer is */
for (j = 0; j < len; ) {
/* fill the buffer with counting (test a) */
for ( ; j < min(len, 32); j++)
buffer[j] = j;
k = j;
/* fill the buffer with alternating words of 0x0 and
* 0xffff (test b) */
for ( ; j < min(len, k + 32); j += 2) {
u16 *word = (u16 *)&buffer[j];
*word = (j & 0x02) ? 0x0000 : 0xffff;
}
k = j;
/* fill with crosstalk (alternating 0x5555 0xaaa)
* (test c) */
for ( ; j < min(len, k + 32); j += 2) {
u16 *word = (u16 *)&buffer[j];
*word = (j & 0x02) ? 0x5555 : 0xaaaa;
}
k = j;
/* fill with shifting bits (test d) */
for ( ; j < min(len, k + 32); j += 4) {
u32 *word = (unsigned int *)&buffer[j];
u32 roll = (pattern & 0x80000000) ? 1 : 0;
*word = pattern;
pattern = (pattern << 1) | roll;
}
/* don't bother with random data (test e) */
}
for (r = 0; r < retries; r++) {
result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
buffer, len, &sshdr);
if(result || !scsi_device_online(sdev)) {
scsi_device_set_state(sdev, SDEV_QUIESCE);
if (scsi_sense_valid(&sshdr)
&& sshdr.sense_key == ILLEGAL_REQUEST
/* INVALID FIELD IN CDB */
&& sshdr.asc == 0x24 && sshdr.ascq == 0x00)
/* This would mean that the drive lied
* to us about supporting an echo
* buffer (unfortunately some Western
* Digital drives do precisely this)
*/
return SPI_COMPARE_SKIP_TEST;
sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
return SPI_COMPARE_FAILURE;
}
memset(ptr, 0, len);
spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
ptr, len, NULL);
scsi_device_set_state(sdev, SDEV_QUIESCE);
if (memcmp(buffer, ptr, len) != 0)
return SPI_COMPARE_FAILURE;
}
return SPI_COMPARE_SUCCESS;
}
/* This is for the simplest form of Domain Validation: a read test
* on the inquiry data from the device */
static enum spi_compare_returns
spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
u8 *ptr, const int retries)
{
int r, result;
const int len = sdev->inquiry_len;
const char spi_inquiry[] = {
INQUIRY, 0, 0, 0, len, 0
};
for (r = 0; r < retries; r++) {
memset(ptr, 0, len);
result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
ptr, len, NULL);
if(result || !scsi_device_online(sdev)) {
scsi_device_set_state(sdev, SDEV_QUIESCE);
return SPI_COMPARE_FAILURE;
}
/* If we don't have the inquiry data already, the
* first read gets it */
if (ptr == buffer) {
ptr += len;
--r;
continue;
}
if (memcmp(buffer, ptr, len) != 0)
/* failure */
return SPI_COMPARE_FAILURE;
}
return SPI_COMPARE_SUCCESS;
}
static enum spi_compare_returns
spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
enum spi_compare_returns
(*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
{
struct spi_internal *i = to_spi_internal(sdev->host->transportt);
struct scsi_target *starget = sdev->sdev_target;
int period = 0, prevperiod = 0;
enum spi_compare_returns retval;
for (;;) {
int newperiod;
retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
if (retval == SPI_COMPARE_SUCCESS
|| retval == SPI_COMPARE_SKIP_TEST)
break;
/* OK, retrain, fallback */
if (i->f->get_iu)
i->f->get_iu(starget);
if (i->f->get_qas)
i->f->get_qas(starget);
if (i->f->get_period)
i->f->get_period(sdev->sdev_target);
/* Here's the fallback sequence; first try turning off
* IU, then QAS (if we can control them), then finally
* fall down the periods */
if (i->f->set_iu && spi_iu(starget)) {
starget_printk(KERN_ERR, starget, "Domain Validation Disabing Information Units\n");
DV_SET(iu, 0);
} else if (i->f->set_qas && spi_qas(starget)) {
starget_printk(KERN_ERR, starget, "Domain Validation Disabing Quick Arbitration and Selection\n");
DV_SET(qas, 0);
} else {
newperiod = spi_period(starget);
period = newperiod > period ? newperiod : period;
if (period < 0x0d)
period++;
else
period += period >> 1;
if (unlikely(period > 0xff || period == prevperiod)) {
/* Total failure; set to async and return */
starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
DV_SET(offset, 0);
return SPI_COMPARE_FAILURE;
}
starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
DV_SET(period, period);
prevperiod = period;
}
}
return retval;
}
static int
spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
{
int l, result;
/* first off do a test unit ready. This can error out
* because of reservations or some other reason. If it
* fails, the device won't let us write to the echo buffer
* so just return failure */
const char spi_test_unit_ready[] = {
TEST_UNIT_READY, 0, 0, 0, 0, 0
};
const char spi_read_buffer_descriptor[] = {
READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
};
/* We send a set of three TURs to clear any outstanding
* unit attention conditions if they exist (Otherwise the
* buffer tests won't be happy). If the TUR still fails
* (reservation conflict, device not ready, etc) just
* skip the write tests */
for (l = 0; ; l++) {
result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE,
NULL, 0, NULL);
if(result) {
if(l >= 3)
return 0;
} else {
/* TUR succeeded */
break;
}
}
result = spi_execute(sdev, spi_read_buffer_descriptor,
DMA_FROM_DEVICE, buffer, 4, NULL);
if (result)
/* Device has no echo buffer */
return 0;
return buffer[3] + ((buffer[2] & 0x1f) << 8);
}
static void
spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
{
struct spi_internal *i = to_spi_internal(sdev->host->transportt);
struct scsi_target *starget = sdev->sdev_target;
struct Scsi_Host *shost = sdev->host;
int len = sdev->inquiry_len;
int min_period = spi_min_period(starget);
int max_width = spi_max_width(starget);
/* first set us up for narrow async */
DV_SET(offset, 0);
DV_SET(width, 0);
if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
!= SPI_COMPARE_SUCCESS) {
starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
/* FIXME: should probably offline the device here? */
return;
}
if (!scsi_device_wide(sdev)) {
spi_max_width(starget) = 0;
max_width = 0;
}
/* test width */
if (i->f->set_width && max_width) {
i->f->set_width(starget, 1);
if (spi_dv_device_compare_inquiry(sdev, buffer,
buffer + len,
DV_LOOPS)
!= SPI_COMPARE_SUCCESS) {
starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
i->f->set_width(starget, 0);
/* Make sure we don't force wide back on by asking
* for a transfer period that requires it */
max_width = 0;
if (min_period < 10)
min_period = 10;
}
}
if (!i->f->set_period)
return;
/* device can't handle synchronous */
if (!scsi_device_sync(sdev) && !scsi_device_dt(sdev))
return;
/* len == -1 is the signal that we need to ascertain the
* presence of an echo buffer before trying to use it. len ==
* 0 means we don't have an echo buffer */
len = -1;
retry:
/* now set up to the maximum */
DV_SET(offset, spi_max_offset(starget));
DV_SET(period, min_period);
/* try QAS requests; this should be harmless to set if the
* target supports it */
if (scsi_device_qas(sdev)) {
DV_SET(qas, 1);
} else {
DV_SET(qas, 0);
}
if (scsi_device_ius(sdev) && min_period < 9) {
/* This u320 (or u640). Set IU transfers */
DV_SET(iu, 1);
/* Then set the optional parameters */
DV_SET(rd_strm, 1);
DV_SET(wr_flow, 1);
DV_SET(rti, 1);
if (min_period == 8)
DV_SET(pcomp_en, 1);
} else {
DV_SET(iu, 0);
}
/* now that we've done all this, actually check the bus
* signal type (if known). Some devices are stupid on
* a SE bus and still claim they can try LVD only settings */
if (i->f->get_signalling)
i->f->get_signalling(shost);
if (spi_signalling(shost) == SPI_SIGNAL_SE ||
spi_signalling(shost) == SPI_SIGNAL_HVD ||
!scsi_device_dt(sdev)) {
DV_SET(dt, 0);
} else {
DV_SET(dt, 1);
}
/* set width last because it will pull all the other
* parameters down to required values */
DV_SET(width, max_width);
/* Do the read only INQUIRY tests */
spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
spi_dv_device_compare_inquiry);
/* See if we actually managed to negotiate and sustain DT */
if (i->f->get_dt)
i->f->get_dt(starget);
/* see if the device has an echo buffer. If it does we can do
* the SPI pattern write tests. Because of some broken
* devices, we *only* try this on a device that has actually
* negotiated DT */
if (len == -1 && spi_dt(starget))
len = spi_dv_device_get_echo_buffer(sdev, buffer);
if (len <= 0) {
starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
return;
}
if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
len = SPI_MAX_ECHO_BUFFER_SIZE;
}
if (spi_dv_retrain(sdev, buffer, buffer + len,
spi_dv_device_echo_buffer)
== SPI_COMPARE_SKIP_TEST) {
/* OK, the stupid drive can't do a write echo buffer
* test after all, fall back to the read tests */
len = 0;
goto retry;
}
}
/** spi_dv_device - Do Domain Validation on the device
* @sdev: scsi device to validate
*
* Performs the domain validation on the given device in the
* current execution thread. Since DV operations may sleep,
* the current thread must have user context. Also no SCSI
* related locks that would deadlock I/O issued by the DV may
* be held.
*/
void
spi_dv_device(struct scsi_device *sdev)
{
struct scsi_target *starget = sdev->sdev_target;
u8 *buffer;
const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
if (unlikely(scsi_device_get(sdev)))
return;
if (unlikely(spi_dv_in_progress(starget)))
return;
spi_dv_in_progress(starget) = 1;
buffer = kzalloc(len, GFP_KERNEL);
if (unlikely(!buffer))
goto out_put;
/* We need to verify that the actual device will quiesce; the
* later target quiesce is just a nice to have */
if (unlikely(scsi_device_quiesce(sdev)))
goto out_free;
scsi_target_quiesce(starget);
spi_dv_pending(starget) = 1;
mutex_lock(&spi_dv_mutex(starget));
starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
spi_dv_device_internal(sdev, buffer);
starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
mutex_unlock(&spi_dv_mutex(starget));
spi_dv_pending(starget) = 0;
scsi_target_resume(starget);
spi_initial_dv(starget) = 1;
out_free:
kfree(buffer);
out_put:
spi_dv_in_progress(starget) = 0;
scsi_device_put(sdev);
}
EXPORT_SYMBOL(spi_dv_device);