[IA64-SGI] snsc_event.c new file

Forgot the "bk new" to add this file. Part of the patch
from Greg Howard

Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 304 insertions, 0 deletions

diff --git a/drivers/char/snsc_event.c b/drivers/char/snsc_event.c
new file mode 100644
index 000000000000..d692af57213a
--- /dev/null
+++ b/drivers/char/snsc_event.c
@@ -0,0 +1,304 @@
+/*
+ * 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 "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;
+
+        /* record event source address */
+        *src = be32_to_cpup((__be32 *)event);
+        event += 4;                     /* move on to event code */
+
+        /* record the system controller's event code */
+        *code = be32_to_cpup((__be32 *)event);
+        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;
+        }
+        *esp_code = be32_to_cpup((__be32 *)event);
+        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;
+        }
+}
+
+