static struct subchannel *
css_alloc_subchannel(struct subchannel_id schid)
{
struct subchannel *sch;
int ret;
sch = kmalloc (sizeof (*sch), GFP_KERNEL | GFP_DMA);
if (sch == NULL)
return ERR_PTR(-ENOMEM);
ret = cio_validate_subchannel (sch, schid);
if (ret < 0) {
kfree(sch);
return ERR_PTR(ret);
}
if (sch->st != SUBCHANNEL_TYPE_IO) {
/* For now we ignore all non-io subchannels. */
kfree(sch);
return ERR_PTR(-EINVAL);
}
/*
* Set intparm to subchannel address.
* This is fine even on 64bit since the subchannel is always located
* under 2G.
*/
sch->schib.pmcw.intparm = (__u32)(unsigned long)sch;
ret = cio_modify(sch);
if (ret) {
kfree(sch);
return ERR_PTR(ret);
}
return sch;
}
struct subchannel *
cio_probe_console(void)
{
int irq, ret;
if (xchg(&console_subchannel_in_use, 1) != 0)
return ERR_PTR(-EBUSY);
irq = cio_console_irq();
if (irq == -1) {
console_subchannel_in_use = 0;
return ERR_PTR(-ENODEV);
}
memset(&console_subchannel, 0, sizeof(struct subchannel));
ret = cio_validate_subchannel(&console_subchannel, irq);
if (ret) {
console_subchannel_in_use = 0;
return ERR_PTR(-ENODEV);
}
/*
* enable console I/O-interrupt subclass 7
*/
ctl_set_bit(6, 24);
console_subchannel.schib.pmcw.isc = 7;
console_subchannel.schib.pmcw.intparm =
(__u32)(unsigned long)&console_subchannel;
ret = cio_modify(&console_subchannel);
if (ret) {
console_subchannel_in_use = 0;
return ERR_PTR(ret);
}
return &console_subchannel;
}
void
cio_release_console(void)
{
console_subchannel.schib.pmcw.intparm = 0;
cio_modify(&console_subchannel);
ctl_clear_bit(6, 24);
console_subchannel_in_use = 0;
}
static void
css_free_subchannel(struct subchannel *sch)
{
if (sch) {
/* Reset intparm to zeroes. */
sch->schib.pmcw.intparm = 0;
cio_modify(sch);
kfree(sch);
}
}
/**
* cio_disable_subchannel - disable a subchannel.
* @sch: subchannel to disable
*/
int cio_disable_subchannel(struct subchannel *sch)
{
char dbf_txt[15];
int ccode;
int retry;
int ret;
CIO_TRACE_EVENT (2, "dissch");
CIO_TRACE_EVENT(2, dev_name(&sch->dev));
if (sch_is_pseudo_sch(sch))
return 0;
ccode = stsch (sch->schid, &sch->schib);
if (ccode == 3) /* Not operational. */
return -ENODEV;
if (scsw_actl(&sch->schib.scsw) != 0)
/*
* the disable function must not be called while there are
* requests pending for completion !
*/
return -EBUSY;
for (retry = 5, ret = 0; retry > 0; retry--) {
sch->schib.pmcw.ena = 0;
ret = cio_modify(sch);
if (ret == -ENODEV)
break;
if (ret == -EBUSY)
/*
* The subchannel is busy or status pending.
* We'll disable when the next interrupt was delivered
* via the state machine.
*/
break;
if (ret == 0) {
stsch (sch->schid, &sch->schib);
if (!sch->schib.pmcw.ena)
break;
}
}
sprintf (dbf_txt, "ret:%d", ret);
CIO_TRACE_EVENT (2, dbf_txt);
return ret;
}
/**
* cio_enable_subchannel - enable a subchannel.
* @sch: subchannel to be enabled
* @intparm: interruption parameter to set
*/
int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
{
char dbf_txt[15];
int ccode;
int retry;
int ret;
CIO_TRACE_EVENT (2, "ensch");
CIO_TRACE_EVENT(2, dev_name(&sch->dev));
if (sch_is_pseudo_sch(sch))
return -EINVAL;
ccode = stsch (sch->schid, &sch->schib);
if (ccode)
return -ENODEV;
for (retry = 5, ret = 0; retry > 0; retry--) {
sch->schib.pmcw.ena = 1;
sch->schib.pmcw.isc = sch->isc;
sch->schib.pmcw.intparm = intparm;
ret = cio_modify(sch);
if (ret == -ENODEV)
break;
if (ret == -EIO)
/*
* Got a program check in cio_modify. Try without
* the concurrent sense bit the next time.
*/
sch->schib.pmcw.csense = 0;
if (ret == 0) {
stsch (sch->schid, &sch->schib);
if (sch->schib.pmcw.ena)
break;
}
if (ret == -EBUSY) {
struct irb irb;
if (tsch(sch->schid, &irb) != 0)
break;
}
}
sprintf (dbf_txt, "ret:%d", ret);
CIO_TRACE_EVENT (2, dbf_txt);
return ret;
}
/*
* Enable subchannel.
*/
int
cio_enable_subchannel (struct subchannel *sch, unsigned int isc)
{
char dbf_txt[15];
int ccode;
int retry;
int ret;
CIO_TRACE_EVENT (2, "ensch");
CIO_TRACE_EVENT (2, sch->dev.bus_id);
ccode = stsch (sch->irq, &sch->schib);
if (ccode)
return -ENODEV;
for (retry = 5, ret = 0; retry > 0; retry--) {
sch->schib.pmcw.ena = 1;
sch->schib.pmcw.isc = isc;
sch->schib.pmcw.intparm = (__u32)(unsigned long)sch;
ret = cio_modify(sch);
if (ret == -ENODEV)
break;
if (ret == -EIO)
/*
* Got a program check in cio_modify. Try without
* the concurrent sense bit the next time.
*/
sch->schib.pmcw.csense = 0;
if (ret == 0) {
stsch (sch->irq, &sch->schib);
if (sch->schib.pmcw.ena)
break;
}
if (ret == -EBUSY) {
struct irb irb;
if (tsch(sch->irq, &irb) != 0)
break;
}
}
sprintf (dbf_txt, "ret:%d", ret);
CIO_TRACE_EVENT (2, dbf_txt);
return ret;
}
/*
* Disable subchannel.
*/
int
cio_disable_subchannel (struct subchannel *sch)
{
char dbf_txt[15];
int ccode;
int retry;
int ret;
sprintf (dbf_txt, "dissch%x", sch->irq);
CIO_TRACE_EVENT (2, dbf_txt);
ccode = stsch (sch->irq, &sch->schib);
if (ccode == 3) /* Not operational. */
return -ENODEV;
if (sch->schib.scsw.actl != 0)
/*
* the disable function must not be called while there are
* requests pending for completion !
*/
return -EBUSY;
sch->schib.pmcw.ena = 0;
for (retry = 5, ret = 0; retry > 0; retry--) {
ret = cio_modify(sch);
if (ret == -ENODEV)
break;
if (ret == 0) {
stsch (sch->irq, &sch->schib);
if (!sch->schib.pmcw.ena)
break;
}
}
sprintf (dbf_txt, "ret:%d", ret);
CIO_TRACE_EVENT (2, dbf_txt);
return ret;
}
struct subchannel *
cio_probe_console(void)
{
int sch_no, ret;
struct subchannel_id schid;
if (xchg(&console_subchannel_in_use, 1) != 0)
return ERR_PTR(-EBUSY);
sch_no = cio_get_console_sch_no();
if (sch_no == -1) {
console_subchannel_in_use = 0;
return ERR_PTR(-ENODEV);
}
memset(&console_subchannel, 0, sizeof(struct subchannel));
init_subchannel_id(&schid);
schid.sch_no = sch_no;
ret = cio_validate_subchannel(&console_subchannel, schid);
if (ret) {
console_subchannel_in_use = 0;
return ERR_PTR(-ENODEV);
}
/*
* enable console I/O-interrupt subclass 7
*/
ctl_set_bit(6, 24);
console_subchannel.schib.pmcw.isc = 7;
console_subchannel.schib.pmcw.intparm =
(__u32)(unsigned long)&console_subchannel;
ret = cio_modify(&console_subchannel);
if (ret) {
console_subchannel_in_use = 0;
return ERR_PTR(ret);
}
return &console_subchannel;
}
static int
css_evaluate_subchannel(int irq, int slow)
{
int event, ret, disc;
struct subchannel *sch;
unsigned long flags;
sch = get_subchannel_by_schid(irq);
disc = sch ? device_is_disconnected(sch) : 0;
if (disc && slow) {
if (sch)
put_device(&sch->dev);
return 0; /* Already processed. */
}
/*
* We've got a machine check, so running I/O won't get an interrupt.
* Kill any pending timers.
*/
if (sch)
device_kill_pending_timer(sch);
if (!disc && !slow) {
if (sch)
put_device(&sch->dev);
return -EAGAIN; /* Will be done on the slow path. */
}
event = css_get_subchannel_status(sch, irq);
CIO_MSG_EVENT(4, "Evaluating schid %04x, event %d, %s, %s path.\n",
irq, event, sch?(disc?"disconnected":"normal"):"unknown",
slow?"slow":"fast");
switch (event) {
case CIO_NO_PATH:
case CIO_GONE:
if (!sch) {
/* Never used this subchannel. Ignore. */
ret = 0;
break;
}
if (disc && (event == CIO_NO_PATH)) {
/*
* Uargh, hack again. Because we don't get a machine
* check on configure on, our path bookkeeping can
* be out of date here (it's fine while we only do
* logical varying or get chsc machine checks). We
* need to force reprobing or we might miss devices
* coming operational again. It won't do harm in real
* no path situations.
*/
spin_lock_irqsave(&sch->lock, flags);
device_trigger_reprobe(sch);
spin_unlock_irqrestore(&sch->lock, flags);
ret = 0;
break;
}
if (sch->driver && sch->driver->notify &&
sch->driver->notify(&sch->dev, event)) {
cio_disable_subchannel(sch);
device_set_disconnected(sch);
ret = 0;
break;
}
/*
* Unregister subchannel.
* The device will be killed automatically.
*/
cio_disable_subchannel(sch);
device_unregister(&sch->dev);
/* Reset intparm to zeroes. */
sch->schib.pmcw.intparm = 0;
cio_modify(sch);
put_device(&sch->dev);
ret = 0;
break;
case CIO_REVALIDATE:
/*
* Revalidation machine check. Sick.
* We don't notify the driver since we have to throw the device
* away in any case.
*/
if (!disc) {
device_unregister(&sch->dev);
/* Reset intparm to zeroes. */
sch->schib.pmcw.intparm = 0;
cio_modify(sch);
put_device(&sch->dev);
ret = css_probe_device(irq);
} else {
/*
* We can't immediately deregister the disconnected
* device since it might block.
*/
spin_lock_irqsave(&sch->lock, flags);
device_trigger_reprobe(sch);
spin_unlock_irqrestore(&sch->lock, flags);
ret = 0;
}
break;
case CIO_OPER:
if (disc) {
spin_lock_irqsave(&sch->lock, flags);
/* Get device operational again. */
device_trigger_reprobe(sch);
spin_unlock_irqrestore(&sch->lock, flags);
}
ret = sch ? 0 : css_probe_device(irq);
break;
default:
BUG();
ret = 0;
}
return ret;
}
