162 lines
4.0 KiB
C
162 lines
4.0 KiB
C
/*
|
|
* Channel report handling code
|
|
*
|
|
* Copyright IBM Corp. 2000,2009
|
|
* Author(s): Ingo Adlung <adlung@de.ibm.com>,
|
|
* Martin Schwidefsky <schwidefsky@de.ibm.com>,
|
|
* Cornelia Huck <cornelia.huck@de.ibm.com>,
|
|
* Heiko Carstens <heiko.carstens@de.ibm.com>,
|
|
*/
|
|
|
|
#include <linux/mutex.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/init.h>
|
|
#include <linux/wait.h>
|
|
#include <asm/crw.h>
|
|
#include <asm/ctl_reg.h>
|
|
|
|
static DEFINE_MUTEX(crw_handler_mutex);
|
|
static crw_handler_t crw_handlers[NR_RSCS];
|
|
static atomic_t crw_nr_req = ATOMIC_INIT(0);
|
|
static DECLARE_WAIT_QUEUE_HEAD(crw_handler_wait_q);
|
|
|
|
/**
|
|
* crw_register_handler() - register a channel report word handler
|
|
* @rsc: reporting source code to handle
|
|
* @handler: handler to be registered
|
|
*
|
|
* Returns %0 on success and a negative error value otherwise.
|
|
*/
|
|
int crw_register_handler(int rsc, crw_handler_t handler)
|
|
{
|
|
int rc = 0;
|
|
|
|
if ((rsc < 0) || (rsc >= NR_RSCS))
|
|
return -EINVAL;
|
|
mutex_lock(&crw_handler_mutex);
|
|
if (crw_handlers[rsc])
|
|
rc = -EBUSY;
|
|
else
|
|
crw_handlers[rsc] = handler;
|
|
mutex_unlock(&crw_handler_mutex);
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* crw_unregister_handler() - unregister a channel report word handler
|
|
* @rsc: reporting source code to handle
|
|
*/
|
|
void crw_unregister_handler(int rsc)
|
|
{
|
|
if ((rsc < 0) || (rsc >= NR_RSCS))
|
|
return;
|
|
mutex_lock(&crw_handler_mutex);
|
|
crw_handlers[rsc] = NULL;
|
|
mutex_unlock(&crw_handler_mutex);
|
|
}
|
|
|
|
/*
|
|
* Retrieve CRWs and call function to handle event.
|
|
*/
|
|
static int crw_collect_info(void *unused)
|
|
{
|
|
struct crw crw[2];
|
|
int ccode, signal;
|
|
unsigned int chain;
|
|
|
|
repeat:
|
|
signal = wait_event_interruptible(crw_handler_wait_q,
|
|
atomic_read(&crw_nr_req) > 0);
|
|
if (unlikely(signal))
|
|
atomic_inc(&crw_nr_req);
|
|
chain = 0;
|
|
while (1) {
|
|
crw_handler_t handler;
|
|
|
|
if (unlikely(chain > 1)) {
|
|
struct crw tmp_crw;
|
|
|
|
printk(KERN_WARNING"%s: Code does not support more "
|
|
"than two chained crws; please report to "
|
|
"linux390@de.ibm.com!\n", __func__);
|
|
ccode = stcrw(&tmp_crw);
|
|
printk(KERN_WARNING"%s: crw reports slct=%d, oflw=%d, "
|
|
"chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
|
|
__func__, tmp_crw.slct, tmp_crw.oflw,
|
|
tmp_crw.chn, tmp_crw.rsc, tmp_crw.anc,
|
|
tmp_crw.erc, tmp_crw.rsid);
|
|
printk(KERN_WARNING"%s: This was crw number %x in the "
|
|
"chain\n", __func__, chain);
|
|
if (ccode != 0)
|
|
break;
|
|
chain = tmp_crw.chn ? chain + 1 : 0;
|
|
continue;
|
|
}
|
|
ccode = stcrw(&crw[chain]);
|
|
if (ccode != 0)
|
|
break;
|
|
printk(KERN_DEBUG "crw_info : CRW reports slct=%d, oflw=%d, "
|
|
"chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
|
|
crw[chain].slct, crw[chain].oflw, crw[chain].chn,
|
|
crw[chain].rsc, crw[chain].anc, crw[chain].erc,
|
|
crw[chain].rsid);
|
|
/* Check for overflows. */
|
|
if (crw[chain].oflw) {
|
|
int i;
|
|
|
|
pr_debug("%s: crw overflow detected!\n", __func__);
|
|
mutex_lock(&crw_handler_mutex);
|
|
for (i = 0; i < NR_RSCS; i++) {
|
|
if (crw_handlers[i])
|
|
crw_handlers[i](NULL, NULL, 1);
|
|
}
|
|
mutex_unlock(&crw_handler_mutex);
|
|
chain = 0;
|
|
continue;
|
|
}
|
|
if (crw[0].chn && !chain) {
|
|
chain++;
|
|
continue;
|
|
}
|
|
mutex_lock(&crw_handler_mutex);
|
|
handler = crw_handlers[crw[chain].rsc];
|
|
if (handler)
|
|
handler(&crw[0], chain ? &crw[1] : NULL, 0);
|
|
mutex_unlock(&crw_handler_mutex);
|
|
/* chain is always 0 or 1 here. */
|
|
chain = crw[chain].chn ? chain + 1 : 0;
|
|
}
|
|
if (atomic_dec_and_test(&crw_nr_req))
|
|
wake_up(&crw_handler_wait_q);
|
|
goto repeat;
|
|
return 0;
|
|
}
|
|
|
|
void crw_handle_channel_report(void)
|
|
{
|
|
atomic_inc(&crw_nr_req);
|
|
wake_up(&crw_handler_wait_q);
|
|
}
|
|
|
|
void crw_wait_for_channel_report(void)
|
|
{
|
|
crw_handle_channel_report();
|
|
wait_event(crw_handler_wait_q, atomic_read(&crw_nr_req) == 0);
|
|
}
|
|
|
|
/*
|
|
* Machine checks for the channel subsystem must be enabled
|
|
* after the channel subsystem is initialized
|
|
*/
|
|
static int __init crw_machine_check_init(void)
|
|
{
|
|
struct task_struct *task;
|
|
|
|
task = kthread_run(crw_collect_info, NULL, "kmcheck");
|
|
if (IS_ERR(task))
|
|
return PTR_ERR(task);
|
|
ctl_set_bit(14, 28); /* enable channel report MCH */
|
|
return 0;
|
|
}
|
|
device_initcall(crw_machine_check_init);
|