android_kernel_xiaomi_sm8350/drivers/scsi/scsi_transport_spi.c
James Bottomley 349cd7cfe6 [SCSI] SPI DV: be more conservative about echo buffer usage
Some SCSI devices apparently get very confused if we try to use the
echo buffer on a non-DT negotiated bus (this mirrors the problems of
using PPR on non-LVD for some devices).  The fix is to be far more
conservative about when we use an echo buffer.  With this patch, we'll
now see what parameters are negotiated by the read only test, and only
look for an echo buffer if DT is negotiated.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-12-01 15:59:43 -06:00

1228 lines
34 KiB
C

/*
* 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 <asm/semaphore.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_pending(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_pending)
#define spi_dv_sem(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_sem)
struct spi_internal {
struct scsi_transport_template t;
struct spi_function_template *f;
/* The actual attributes */
struct class_device_attribute private_attrs[SPI_NUM_ATTRS];
/* The array of null terminated pointers to attributes
* needed by scsi_sysfs.c */
struct class_device_attribute *attrs[SPI_NUM_ATTRS + SPI_OTHER_ATTRS + 1];
struct class_device_attribute private_host_attrs[SPI_HOST_ATTRS];
struct class_device_attribute *host_attrs[SPI_HOST_ATTRS + 1];
};
#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, sizeof(*sense),
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 < sizeof(signal_types)/sizeof(signal_types[0]); 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 < sizeof(signal_types)/sizeof(signal_types[0]); 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 class_device *cdev)
{
struct Scsi_Host *shost = dev_to_shost(dev);
spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
return 0;
}
static DECLARE_TRANSPORT_CLASS(spi_host_class,
"spi_host",
spi_host_setup,
NULL,
NULL);
static int spi_host_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
struct spi_internal *i;
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;
i = to_spi_internal(shost->transportt);
return &i->t.host_attrs.ac == cont;
}
static int spi_device_configure(struct transport_container *tc,
struct device *dev,
struct class_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 class_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_initial_dv(starget) = 0;
init_MUTEX(&spi_dv_sem(starget));
return 0;
}
#define spi_transport_show_simple(field, format_string) \
\
static ssize_t \
show_spi_transport_##field(struct class_device *cdev, char *buf) \
{ \
struct scsi_target *starget = transport_class_to_starget(cdev); \
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 class_device *cdev, const char *buf, \
size_t count) \
{ \
int val; \
struct scsi_target *starget = transport_class_to_starget(cdev); \
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 class_device *cdev, char *buf) \
{ \
struct scsi_target *starget = transport_class_to_starget(cdev); \
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 class_device *cdev, const char *buf, \
size_t count) \
{ \
int val; \
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); \
\
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 class_device *cdev, const char *buf, \
size_t count) \
{ \
int val; \
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; \
\
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 CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR, \
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 CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR, \
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 CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR, \
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 class_device *cdev, const char *buf, size_t count)
{
struct scsi_target *starget = transport_class_to_starget(cdev);
device_for_each_child(&starget->dev, NULL, child_iter);
return count;
}
static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
/* Translate the period into ns according to the current spec
* for SDTR/PPR messages */
static ssize_t
show_spi_transport_period_helper(struct class_device *cdev, 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);
}
buf[len++] = '\n';
buf[len] = '\0';
return len;
}
static ssize_t
store_spi_transport_period_helper(struct class_device *cdev, 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 class_device *cdev, 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->get_period)
i->f->get_period(starget);
return show_spi_transport_period_helper(cdev, buf, tp->period);
}
static ssize_t
store_spi_transport_period(struct class_device *cdev, 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;
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 CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR,
show_spi_transport_period,
store_spi_transport_period);
static ssize_t
show_spi_transport_min_period(struct class_device *cdev, char *buf)
{
struct scsi_target *starget = transport_class_to_starget(cdev);
struct spi_transport_attrs *tp =
(struct spi_transport_attrs *)&starget->starget_data;
return show_spi_transport_period_helper(cdev, buf, tp->min_period);
}
static ssize_t
store_spi_transport_min_period(struct class_device *cdev, 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 CLASS_DEVICE_ATTR(min_period, S_IRUGO | S_IWUSR,
show_spi_transport_min_period,
store_spi_transport_min_period);
static ssize_t show_spi_host_signalling(struct class_device *cdev, 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 class_device *cdev,
const char *buf, size_t count)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct spi_internal *i = to_spi_internal(shost->transportt);
enum spi_signal_type type = spi_signal_to_value(buf);
if (type != SPI_SIGNAL_UNKNOWN)
i->f->set_signalling(shost, type);
return count;
}
static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
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;
int len = sdev->inquiry_len;
/* 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;
}
/* test width */
if (i->f->set_width && spi_max_width(starget) &&
scsi_device_wide(sdev)) {
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);
}
}
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, spi_min_period(starget));
/* try QAS requests; this should be harmless to set if the
* target supports it */
if (scsi_device_qas(sdev))
DV_SET(qas, 1);
/* Also try IU transfers */
if (scsi_device_ius(sdev))
DV_SET(iu, 1);
if (spi_min_period(starget) < 9) {
/* This u320 (or u640). Ignore the coupled parameters
* like DT and IU, but set the optional ones */
DV_SET(rd_strm, 1);
DV_SET(wr_flow, 1);
DV_SET(rti, 1);
if (spi_min_period(starget) == 8)
DV_SET(pcomp_en, 1);
}
/* 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;
buffer = kmalloc(len, GFP_KERNEL);
if (unlikely(!buffer))
goto out_put;
memset(buffer, 0, len);
/* 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;
down(&spi_dv_sem(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");
up(&spi_dv_sem(starget));
spi_dv_pending(starget) = 0;
scsi_target_resume(starget);
spi_initial_dv(starget) = 1;
out_free:
kfree(buffer);
out_put:
scsi_device_put(sdev);
}
EXPORT_SYMBOL(spi_dv_device);
struct work_queue_wrapper {
struct work_struct work;
struct scsi_device *sdev;
};
static void
spi_dv_device_work_wrapper(void *data)
{
struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
struct scsi_device *sdev = wqw->sdev;
kfree(wqw);
spi_dv_device(sdev);
spi_dv_pending(sdev->sdev_target) = 0;
scsi_device_put(sdev);
}
/**
* spi_schedule_dv_device - schedule domain validation to occur on the device
* @sdev: The device to validate
*
* Identical to spi_dv_device() above, except that the DV will be
* scheduled to occur in a workqueue later. All memory allocations
* are atomic, so may be called from any context including those holding
* SCSI locks.
*/
void
spi_schedule_dv_device(struct scsi_device *sdev)
{
struct work_queue_wrapper *wqw =
kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
if (unlikely(!wqw))
return;
if (unlikely(spi_dv_pending(sdev->sdev_target))) {
kfree(wqw);
return;
}
/* Set pending early (dv_device doesn't check it, only sets it) */
spi_dv_pending(sdev->sdev_target) = 1;
if (unlikely(scsi_device_get(sdev))) {
kfree(wqw);
spi_dv_pending(sdev->sdev_target) = 0;
return;
}
INIT_WORK(&wqw->work, spi_dv_device_work_wrapper, wqw);
wqw->sdev = sdev;
schedule_work(&wqw->work);
}
EXPORT_SYMBOL(spi_schedule_dv_device);
/**
* spi_display_xfer_agreement - Print the current target transfer agreement
* @starget: The target for which to display the agreement
*
* Each SPI port is required to maintain a transfer agreement for each
* other port on the bus. This function prints a one-line summary of
* the current agreement; more detailed information is available in sysfs.
*/
void spi_display_xfer_agreement(struct scsi_target *starget)
{
struct spi_transport_attrs *tp;
tp = (struct spi_transport_attrs *)&starget->starget_data;
if (tp->offset > 0 && tp->period > 0) {
unsigned int picosec, kb100;
char *scsi = "FAST-?";
char tmp[8];
if (tp->period <= SPI_STATIC_PPR) {
picosec = ppr_to_ps[tp->period];
switch (tp->period) {
case 7: scsi = "FAST-320"; break;
case 8: scsi = "FAST-160"; break;
case 9: scsi = "FAST-80"; break;
case 10:
case 11: scsi = "FAST-40"; break;
case 12: scsi = "FAST-20"; break;
}
} else {
picosec = tp->period * 4000;
if (tp->period < 25)
scsi = "FAST-20";
else if (tp->period < 50)
scsi = "FAST-10";
else
scsi = "FAST-5";
}
kb100 = (10000000 + picosec / 2) / picosec;
if (tp->width)
kb100 *= 2;
sprint_frac(tmp, picosec, 1000);
dev_info(&starget->dev,
"%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
tp->dt ? "DT" : "ST",
tp->iu ? " IU" : "",
tp->qas ? " QAS" : "",
tp->rd_strm ? " RDSTRM" : "",
tp->rti ? " RTI" : "",
tp->wr_flow ? " WRFLOW" : "",
tp->pcomp_en ? " PCOMP" : "",
tp->hold_mcs ? " HMCS" : "",
tmp, tp->offset);
} else {
dev_info(&starget->dev, "%sasynchronous.\n",
tp->width ? "wide " : "");
}
}
EXPORT_SYMBOL(spi_display_xfer_agreement);
#define SETUP_ATTRIBUTE(field) \
i->private_attrs[count] = class_device_attr_##field; \
if (!i->f->set_##field) { \
i->private_attrs[count].attr.mode = S_IRUGO; \
i->private_attrs[count].store = NULL; \
} \
i->attrs[count] = &i->private_attrs[count]; \
if (i->f->show_##field) \
count++
#define SETUP_RELATED_ATTRIBUTE(field, rel_field) \
i->private_attrs[count] = class_device_attr_##field; \
if (!i->f->set_##rel_field) { \
i->private_attrs[count].attr.mode = S_IRUGO; \
i->private_attrs[count].store = NULL; \
} \
i->attrs[count] = &i->private_attrs[count]; \
if (i->f->show_##rel_field) \
count++
#define SETUP_HOST_ATTRIBUTE(field) \
i->private_host_attrs[count] = class_device_attr_##field; \
if (!i->f->set_##field) { \
i->private_host_attrs[count].attr.mode = S_IRUGO; \
i->private_host_attrs[count].store = NULL; \
} \
i->host_attrs[count] = &i->private_host_attrs[count]; \
count++
static int spi_device_match(struct attribute_container *cont,
struct device *dev)
{
struct scsi_device *sdev;
struct Scsi_Host *shost;
struct spi_internal *i;
if (!scsi_is_sdev_device(dev))
return 0;
sdev = to_scsi_device(dev);
shost = sdev->host;
if (!shost->transportt || shost->transportt->host_attrs.ac.class
!= &spi_host_class.class)
return 0;
/* Note: this class has no device attributes, so it has
* no per-HBA allocation and thus we don't need to distinguish
* the attribute containers for the device */
i = to_spi_internal(shost->transportt);
if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
return 0;
return 1;
}
static int spi_target_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
struct scsi_target *starget;
struct spi_internal *i;
if (!scsi_is_target_device(dev))
return 0;
shost = dev_to_shost(dev->parent);
if (!shost->transportt || shost->transportt->host_attrs.ac.class
!= &spi_host_class.class)
return 0;
i = to_spi_internal(shost->transportt);
starget = to_scsi_target(dev);
if (i->f->deny_binding && i->f->deny_binding(starget))
return 0;
return &i->t.target_attrs.ac == cont;
}
static DECLARE_TRANSPORT_CLASS(spi_transport_class,
"spi_transport",
spi_setup_transport_attrs,
NULL,
NULL);
static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
spi_device_match,
spi_device_configure);
struct scsi_transport_template *
spi_attach_transport(struct spi_function_template *ft)
{
struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
GFP_KERNEL);
int count = 0;
if (unlikely(!i))
return NULL;
memset(i, 0, sizeof(struct spi_internal));
i->t.target_attrs.ac.class = &spi_transport_class.class;
i->t.target_attrs.ac.attrs = &i->attrs[0];
i->t.target_attrs.ac.match = spi_target_match;
transport_container_register(&i->t.target_attrs);
i->t.target_size = sizeof(struct spi_transport_attrs);
i->t.host_attrs.ac.class = &spi_host_class.class;
i->t.host_attrs.ac.attrs = &i->host_attrs[0];
i->t.host_attrs.ac.match = spi_host_match;
transport_container_register(&i->t.host_attrs);
i->t.host_size = sizeof(struct spi_host_attrs);
i->f = ft;
SETUP_ATTRIBUTE(period);
SETUP_RELATED_ATTRIBUTE(min_period, period);
SETUP_ATTRIBUTE(offset);
SETUP_RELATED_ATTRIBUTE(max_offset, offset);
SETUP_ATTRIBUTE(width);
SETUP_RELATED_ATTRIBUTE(max_width, width);
SETUP_ATTRIBUTE(iu);
SETUP_ATTRIBUTE(dt);
SETUP_ATTRIBUTE(qas);
SETUP_ATTRIBUTE(wr_flow);
SETUP_ATTRIBUTE(rd_strm);
SETUP_ATTRIBUTE(rti);
SETUP_ATTRIBUTE(pcomp_en);
SETUP_ATTRIBUTE(hold_mcs);
/* if you add an attribute but forget to increase SPI_NUM_ATTRS
* this bug will trigger */
BUG_ON(count > SPI_NUM_ATTRS);
i->attrs[count++] = &class_device_attr_revalidate;
i->attrs[count] = NULL;
count = 0;
SETUP_HOST_ATTRIBUTE(signalling);
BUG_ON(count > SPI_HOST_ATTRS);
i->host_attrs[count] = NULL;
return &i->t;
}
EXPORT_SYMBOL(spi_attach_transport);
void spi_release_transport(struct scsi_transport_template *t)
{
struct spi_internal *i = to_spi_internal(t);
transport_container_unregister(&i->t.target_attrs);
transport_container_unregister(&i->t.host_attrs);
kfree(i);
}
EXPORT_SYMBOL(spi_release_transport);
static __init int spi_transport_init(void)
{
int error = transport_class_register(&spi_transport_class);
if (error)
return error;
error = anon_transport_class_register(&spi_device_class);
return transport_class_register(&spi_host_class);
}
static void __exit spi_transport_exit(void)
{
transport_class_unregister(&spi_transport_class);
anon_transport_class_unregister(&spi_device_class);
transport_class_unregister(&spi_host_class);
}
MODULE_AUTHOR("Martin Hicks");
MODULE_DESCRIPTION("SPI Transport Attributes");
MODULE_LICENSE("GPL");
module_init(spi_transport_init);
module_exit(spi_transport_exit);