diff options
Diffstat (limited to 'arch/ppc64/kernel/ras.c')
| -rw-r--r-- | arch/ppc64/kernel/ras.c | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/ras.c b/arch/ppc64/kernel/ras.c new file mode 100644 index 000000000000..1c4c796b212b --- /dev/null +++ b/arch/ppc64/kernel/ras.c @@ -0,0 +1,356 @@ +/* + * ras.c + * 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/iSeries/LparData.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; + +extern void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr); + +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; +} |