/*
* SN Platform system controller communication support
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2004 Silicon Graphics, Inc. All rights reserved.
*/
/*
* System controller event handler
*
* These routines deal with environmental events arriving from the
* system controllers.
*/
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/byteorder/generic.h>
#include <asm/sn/sn_sal.h>
#include <asm/unaligned.h>
#include "snsc.h"
static struct subch_data_s *event_sd;
void scdrv_event(unsigned long);
DECLARE_TASKLET(sn_sysctl_event, scdrv_event, 0);
/*
* scdrv_event_interrupt
*
* Pull incoming environmental events off the physical link to the
* system controller and put them in a temporary holding area in SAL.
* Schedule scdrv_event() to move them along to their ultimate
* destination.
*/
static irqreturn_t
scdrv_event_interrupt(int irq, void *subch_data, struct pt_regs *regs)
{
struct subch_data_s *sd = subch_data;
unsigned long flags;
int status;
spin_lock_irqsave(&sd->sd_rlock, flags);
status = ia64_sn_irtr_intr(sd->sd_nasid, sd->sd_subch);
if ((status > 0) && (status & SAL_IROUTER_INTR_RECV)) {
tasklet_schedule(&sn_sysctl_event);
}
spin_unlock_irqrestore(&sd->sd_rlock, flags);
return IRQ_HANDLED;
}
/*
* scdrv_parse_event
*
* Break an event (as read from SAL) into useful pieces so we can decide
* what to do with it.
*/
static int
scdrv_parse_event(char *event, int *src, int *code, int *esp_code, char *desc)
{
char *desc_end;
__be32 from_buf;
/* record event source address */
from_buf = get_unaligned((__be32 *)event);
*src = be32_to_cpup(&from_buf);
event += 4; /* move on to event code */
/* record the system controller's event code */
from_buf = get_unaligned((__be32 *)event);
*code = be32_to_cpup(&from_buf);
event += 4; /* move on to event arguments */
/* how many arguments are in the packet? */
if (*event++ != 2) {
/* if not 2, give up */
return -1;
}
/* parse out the ESP code */
if (*event++ != IR_ARG_INT) {
/* not an integer argument, so give up */
return -1;
}
from_buf = get_unaligned((__be32 *)event);
*esp_code = be32_to_cpup(&from_buf);
event += 4;
/* parse out the event description */
if (*event++ != IR_ARG_ASCII) {
/* not an ASCII string, so give up */
return -1;
}
event[CHUNKSIZE-1] = '\0'; /* ensure this string ends! */
event += 2; /* skip leading CR/LF */
desc_end = desc + sprintf(desc, "%s", event);
/* strip trailing CR/LF (if any) */
for (desc_end--;
(desc_end != desc) && ((*desc_end == 0xd) || (*desc_end == 0xa));
desc_end--) {
*desc_end = '\0';
}
return 0;
}
/*
* scdrv_event_severity
*
* Figure out how urgent a message we should write to the console/syslog
* via printk.
*/
static char *
scdrv_event_severity(int code)
{
int ev_class = (code & EV_CLASS_MASK);
int ev_severity = (code & EV_SEVERITY_MASK);
char *pk_severity = KERN_NOTICE;
switch (ev_class) {
case EV_CLASS_POWER:
switch (ev_severity) {
case EV_SEVERITY_POWER_LOW_WARNING:
case EV_SEVERITY_POWER_HIGH_WARNING:
pk_severity = KERN_WARNING;
break;
case EV_SEVERITY_POWER_HIGH_FAULT:
case EV_SEVERITY_POWER_LOW_FAULT:
pk_severity = KERN_ALERT;
break;
}
break;
case EV_CLASS_FAN:
switch (ev_severity) {
case EV_SEVERITY_FAN_WARNING:
pk_severity = KERN_WARNING;
break;
case EV_SEVERITY_FAN_FAULT:
pk_severity = KERN_CRIT;
break;
}
break;
case EV_CLASS_TEMP:
switch (ev_severity) {
case EV_SEVERITY_TEMP_ADVISORY:
pk_severity = KERN_WARNING;
break;
case EV_SEVERITY_TEMP_CRITICAL:
pk_severity = KERN_CRIT;
break;
case EV_SEVERITY_TEMP_FAULT:
pk_severity = KERN_ALERT;
break;
}
break;
case EV_CLASS_ENV:
pk_severity = KERN_ALERT;
break;
case EV_CLASS_TEST_FAULT:
pk_severity = KERN_ALERT;
break;
case EV_CLASS_TEST_WARNING:
pk_severity = KERN_WARNING;
break;
case EV_CLASS_PWRD_NOTIFY:
pk_severity = KERN_ALERT;
break;
}
return pk_severity;
}
/*
* scdrv_dispatch_event
*
* Do the right thing with an incoming event. That's often nothing
* more than printing it to the system log. For power-down notifications
* we start a graceful shutdown.
*/
static void
scdrv_dispatch_event(char *event, int len)
{
int code, esp_code, src;
char desc[CHUNKSIZE];
char *severity;
if (scdrv_parse_event(event, &src, &code, &esp_code, desc) < 0) {
/* ignore uninterpretible event */
return;
}
/* how urgent is the message? */
severity = scdrv_event_severity(code);
if ((code & EV_CLASS_MASK) == EV_CLASS_PWRD_NOTIFY) {
struct task_struct *p;
/* give a SIGPWR signal to init proc */
/* first find init's task */
read_lock(&tasklist_lock);
for_each_process(p) {
if (p->pid == 1)
break;
}
if (p) { /* we found init's task */
printk(KERN_EMERG "Power off indication received. Initiating power fail sequence...\n");
force_sig(SIGPWR, p);
} else { /* failed to find init's task - just give message(s) */
printk(KERN_WARNING "Failed to find init proc to handle power off!\n");
printk("%s|$(0x%x)%s\n", severity, esp_code, desc);
}
read_unlock(&tasklist_lock);
} else {
/* print to system log */
printk("%s|$(0x%x)%s\n", severity, esp_code, desc);
}
}
/*
* scdrv_event
*
* Called as a tasklet when an event arrives from the L1. Read the event
* from where it's temporarily stored in SAL and call scdrv_dispatch_event()
* to send it on its way. Keep trying to read events until SAL indicates
* that there are no more immediately available.
*/
void
scdrv_event(unsigned long dummy)
{
int status;
int len;
unsigned long flags;
struct subch_data_s *sd = event_sd;
/* anything to read? */
len = CHUNKSIZE;
spin_lock_irqsave(&sd->sd_rlock, flags);
status = ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch,
sd->sd_rb, &len);
while (!(status < 0)) {
spin_unlock_irqrestore(&sd->sd_rlock, flags);
scdrv_dispatch_event(sd->sd_rb, len);
len = CHUNKSIZE;
spin_lock_irqsave(&sd->sd_rlock, flags);
status = ia64_sn_irtr_recv(sd->sd_nasid, sd->sd_subch,
sd->sd_rb, &len);
}
spin_unlock_irqrestore(&sd->sd_rlock, flags);
}
/*
* scdrv_event_init
*
* Sets up a system controller subchannel to begin receiving event
* messages. This is sort of a specialized version of scdrv_open()
* in drivers/char/sn_sysctl.c.
*/
void
scdrv_event_init(struct sysctl_data_s *scd)
{
int rv;
event_sd = kmalloc(sizeof (struct subch_data_s), GFP_KERNEL);
if (event_sd == NULL) {
printk(KERN_WARNING "%s: couldn't allocate subchannel info"
" for event monitoring\n", __FUNCTION__);
return;
}
/* initialize subch_data_s fields */
memset(event_sd, 0, sizeof (struct subch_data_s));
event_sd->sd_nasid = scd->scd_nasid;
spin_lock_init(&event_sd->sd_rlock);
/* ask the system controllers to send events to this node */
event_sd->sd_subch = ia64_sn_sysctl_event_init(scd->scd_nasid);
if (event_sd->sd_subch < 0) {
kfree(event_sd);
printk(KERN_WARNING "%s: couldn't open event subchannel\n",
__FUNCTION__);
return;
}
/* hook event subchannel up to the system controller interrupt */
rv = request_irq(SGI_UART_VECTOR, scdrv_event_interrupt,
SA_SHIRQ | SA_INTERRUPT,
"system controller events", event_sd);
if (rv) {
printk(KERN_WARNING "%s: irq request failed (%d)\n",
__FUNCTION__, rv);
ia64_sn_irtr_close(event_sd->sd_nasid, event_sd->sd_subch);
kfree(event_sd);
return;
}
}
