/* * 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/udbg.h> #include <asm/firmware.h> #include "ras.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]; 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); } int 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(); } return 0; /* need to perform reset */ } /* * 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; }