1 files changed, 352 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
new file mode 100644
index 000000000000..6562ff4b0a82
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -0,0 +1,352 @@
+/*
+ * Copyright (C) 2001 Dave Engebretsen IBM Corporation
+ *
+ * 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
+ */
+
+/* Change Activity:
+ * 2001/09/21 : engebret : Created with minimal EPOW and HW exception support.
+ * End Change Activity
+ */
+
+#include <linux/errno.h>
+#include <linux/threads.h>
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/timex.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/random.h>
+#include <linux/sysrq.h>
+#include <linux/bitops.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/cache.h>
+#include <asm/prom.h>
+#include <asm/ptrace.h>
+#include <asm/machdep.h>
+#include <asm/rtas.h>
+#include <asm/ppcdebug.h>
+
+static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX];
+static DEFINE_SPINLOCK(ras_log_buf_lock);
+
+char mce_data_buf[RTAS_ERROR_LOG_MAX]
+;
+/* This is true if we are using the firmware NMI handler (typically LPAR) */
+extern int fwnmi_active;
+
+static int ras_get_sensor_state_token;
+static int ras_check_exception_token;
+
+#define EPOW_SENSOR_TOKEN       9
+#define EPOW_SENSOR_INDEX       0
+#define RAS_VECTOR_OFFSET       0x500
+
+static irqreturn_t ras_epow_interrupt(int irq, void *dev_id,
+                                        struct pt_regs * regs);
+static irqreturn_t ras_error_interrupt(int irq, void *dev_id,
+                                        struct pt_regs * regs);
+
+/* #define DEBUG */
+
+static void request_ras_irqs(struct device_node *np, char *propname,
+                        irqreturn_t (*handler)(int, void *, struct pt_regs *),
+                        const char *name)
+{
+        unsigned int *ireg, len, i;
+        int virq, n_intr;
+
+        ireg = (unsigned int *)get_property(np, propname, &len);
+        if (ireg == NULL)
+                return;
+        n_intr = prom_n_intr_cells(np);
+        len /= n_intr * sizeof(*ireg);
+
+        for (i = 0; i < len; i++) {
+                virq = virt_irq_create_mapping(*ireg);
+                if (virq == NO_IRQ) {
+                        printk(KERN_ERR "Unable to allocate interrupt "
+                               "number for %s\n", np->full_name);
+                        return;
+                }
+                if (request_irq(irq_offset_up(virq), handler, 0, name, NULL)) {
+                        printk(KERN_ERR "Unable to request interrupt %d for "
+                               "%s\n", irq_offset_up(virq), np->full_name);
+                        return;
+                }
+                ireg += n_intr;
+        }
+}
+
+/*
+ * Initialize handlers for the set of interrupts caused by hardware errors
+ * and power system events.
+ */
+static int __init init_ras_IRQ(void)
+{
+        struct device_node *np;
+
+        ras_get_sensor_state_token = rtas_token("get-sensor-state");
+        ras_check_exception_token = rtas_token("check-exception");
+
+        /* Internal Errors */
+        np = of_find_node_by_path("/event-sources/internal-errors");
+        if (np != NULL) {
+                request_ras_irqs(np, "open-pic-interrupt", ras_error_interrupt,
+                                 "RAS_ERROR");
+                request_ras_irqs(np, "interrupts", ras_error_interrupt,
+                                 "RAS_ERROR");
+                of_node_put(np);
+        }
+
+        /* EPOW Events */
+        np = of_find_node_by_path("/event-sources/epow-events");
+        if (np != NULL) {
+                request_ras_irqs(np, "open-pic-interrupt", ras_epow_interrupt,
+                                 "RAS_EPOW");
+                request_ras_irqs(np, "interrupts", ras_epow_interrupt,
+                                 "RAS_EPOW");
+                of_node_put(np);
+        }
+
+        return 1;
+}
+__initcall(init_ras_IRQ);
+
+/*
+ * Handle power subsystem events (EPOW).
+ *
+ * Presently we just log the event has occurred.  This should be fixed
+ * to examine the type of power failure and take appropriate action where
+ * the time horizon permits something useful to be done.
+ */
+static irqreturn_t
+ras_epow_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+        int status = 0xdeadbeef;
+        int state = 0;
+        int critical;
+
+        status = rtas_call(ras_get_sensor_state_token, 2, 2, &state,
+                           EPOW_SENSOR_TOKEN, EPOW_SENSOR_INDEX);
+
+        if (state > 3)
+                critical = 1;  /* Time Critical */
+        else
+                critical = 0;
+
+        spin_lock(&ras_log_buf_lock);
+
+        status = rtas_call(ras_check_exception_token, 6, 1, NULL,
+                           RAS_VECTOR_OFFSET,
+                           virt_irq_to_real(irq_offset_down(irq)),
+                           RTAS_EPOW_WARNING | RTAS_POWERMGM_EVENTS,
+                           critical, __pa(&ras_log_buf),
+                                rtas_get_error_log_max());
+
+        udbg_printf("EPOW <0x%lx 0x%x 0x%x>\n",
+                    *((unsigned long *)&ras_log_buf), status, state);
+        printk(KERN_WARNING "EPOW <0x%lx 0x%x 0x%x>\n",
+               *((unsigned long *)&ras_log_buf), status, state);
+
+        /* format and print the extended information */
+        log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0);
+
+        spin_unlock(&ras_log_buf_lock);
+        return IRQ_HANDLED;
+}
+
+/*
+ * Handle hardware error interrupts.
+ *
+ * RTAS check-exception is called to collect data on the exception.  If
+ * the error is deemed recoverable, we log a warning and return.
+ * For nonrecoverable errors, an error is logged and we stop all processing
+ * as quickly as possible in order to prevent propagation of the failure.
+ */
+static irqreturn_t
+ras_error_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+        struct rtas_error_log *rtas_elog;
+        int status = 0xdeadbeef;
+        int fatal;
+
+        spin_lock(&ras_log_buf_lock);
+
+        status = rtas_call(ras_check_exception_token, 6, 1, NULL,
+                           RAS_VECTOR_OFFSET,
+                           virt_irq_to_real(irq_offset_down(irq)),
+                           RTAS_INTERNAL_ERROR, 1 /*Time Critical */,
+                           __pa(&ras_log_buf),
+                                rtas_get_error_log_max());
+
+        rtas_elog = (struct rtas_error_log *)ras_log_buf;
+
+        if ((status == 0) && (rtas_elog->severity >= RTAS_SEVERITY_ERROR_SYNC))
+                fatal = 1;
+        else
+                fatal = 0;
+
+        /* format and print the extended information */
+        log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, fatal);
+
+        if (fatal) {
+                udbg_printf("Fatal HW Error <0x%lx 0x%x>\n",
+                            *((unsigned long *)&ras_log_buf), status);
+                printk(KERN_EMERG "Error: Fatal hardware error <0x%lx 0x%x>\n",
+                       *((unsigned long *)&ras_log_buf), status);
+
+#ifndef DEBUG
+                /* Don't actually power off when debugging so we can test
+                 * without actually failing while injecting errors.
+                 * Error data will not be logged to syslog.
+                 */
+                ppc_md.power_off();
+#endif
+        } else {
+                udbg_printf("Recoverable HW Error <0x%lx 0x%x>\n",
+                            *((unsigned long *)&ras_log_buf), status);
+                printk(KERN_WARNING
+                       "Warning: Recoverable hardware error <0x%lx 0x%x>\n",
+                       *((unsigned long *)&ras_log_buf), status);
+        }
+
+        spin_unlock(&ras_log_buf_lock);
+        return IRQ_HANDLED;
+}
+
+/* Get the error information for errors coming through the
+ * FWNMI vectors.  The pt_regs' r3 will be updated to reflect
+ * the actual r3 if possible, and a ptr to the error log entry
+ * will be returned if found.
+ *
+ * The mce_data_buf does not have any locks or protection around it,
+ * if a second machine check comes in, or a system reset is done
+ * before we have logged the error, then we will get corruption in the
+ * error log.  This is preferable over holding off on calling
+ * ibm,nmi-interlock which would result in us checkstopping if a
+ * second machine check did come in.
+ */
+static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
+{
+        unsigned long errdata = regs->gpr[3];
+        struct rtas_error_log *errhdr = NULL;
+        unsigned long *savep;
+
+        if ((errdata >= 0x7000 && errdata < 0x7fff0) ||
+            (errdata >= rtas.base && errdata < rtas.base + rtas.size - 16)) {
+                savep = __va(errdata);
+                regs->gpr[3] = savep[0];        /* restore original r3 */
+                memset(mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
+                memcpy(mce_data_buf, (char *)(savep + 1), RTAS_ERROR_LOG_MAX);
+                errhdr = (struct rtas_error_log *)mce_data_buf;
+        } else {
+                printk("FWNMI: corrupt r3\n");
+        }
+        return errhdr;
+}
+
+/* Call this when done with the data returned by FWNMI_get_errinfo.
+ * It will release the saved data area for other CPUs in the
+ * partition to receive FWNMI errors.
+ */
+static void fwnmi_release_errinfo(void)
+{
+        int ret = rtas_call(rtas_token("ibm,nmi-interlock"), 0, 1, NULL);
+        if (ret != 0)
+                printk("FWNMI: nmi-interlock failed: %d\n", ret);
+}
+
+void pSeries_system_reset_exception(struct pt_regs *regs)
+{
+        if (fwnmi_active) {
+                struct rtas_error_log *errhdr = fwnmi_get_errinfo(regs);
+                if (errhdr) {
+                        /* XXX Should look at FWNMI information */
+                }
+                fwnmi_release_errinfo();
+        }
+}
+
+/*
+ * See if we can recover from a machine check exception.
+ * This is only called on power4 (or above) and only via
+ * the Firmware Non-Maskable Interrupts (fwnmi) handler
+ * which provides the error analysis for us.
+ *
+ * Return 1 if corrected (or delivered a signal).
+ * Return 0 if there is nothing we can do.
+ */
+static int recover_mce(struct pt_regs *regs, struct rtas_error_log * err)
+{
+        int nonfatal = 0;
+
+        if (err->disposition == RTAS_DISP_FULLY_RECOVERED) {
+                /* Platform corrected itself */
+                nonfatal = 1;
+        } else if ((regs->msr & MSR_RI) &&
+                   user_mode(regs) &&
+                   err->severity == RTAS_SEVERITY_ERROR_SYNC &&
+                   err->disposition == RTAS_DISP_NOT_RECOVERED &&
+                   err->target == RTAS_TARGET_MEMORY &&
+                   err->type == RTAS_TYPE_ECC_UNCORR &&
+                   !(current->pid == 0 || current->pid == 1)) {
+                /* Kill off a user process with an ECC error */
+                printk(KERN_ERR "MCE: uncorrectable ecc error for pid %d\n",
+                       current->pid);
+                /* XXX something better for ECC error? */
+                _exception(SIGBUS, regs, BUS_ADRERR, regs->nip);
+                nonfatal = 1;
+        }
+
+        log_error((char *)err, ERR_TYPE_RTAS_LOG, !nonfatal);
+
+        return nonfatal;
+}
+
+/*
+ * Handle a machine check.
+ *
+ * Note that on Power 4 and beyond Firmware Non-Maskable Interrupts (fwnmi)
+ * should be present.  If so the handler which called us tells us if the
+ * error was recovered (never true if RI=0).
+ *
+ * On hardware prior to Power 4 these exceptions were asynchronous which
+ * means we can't tell exactly where it occurred and so we can't recover.
+ */
+int pSeries_machine_check_exception(struct pt_regs *regs)
+{
+        struct rtas_error_log *errp;
+
+        if (fwnmi_active) {
+                errp = fwnmi_get_errinfo(regs);
+                fwnmi_release_errinfo();
+                if (errp && recover_mce(regs, errp))
+                        return 1;
+        }
+
+        return 0;
+}