diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/ras.c')
| -rw-r--r-- | arch/powerpc/platforms/pseries/ras.c | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c new file mode 100644 index 00000000..086d2ae4 --- /dev/null +++ b/arch/powerpc/platforms/pseries/ras.c @@ -0,0 +1,347 @@ +/* + * 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/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 "pseries.h" + +static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX]; +static DEFINE_SPINLOCK(ras_log_buf_lock); + +static char global_mce_data_buf[RTAS_ERROR_LOG_MAX]; +static DEFINE_PER_CPU(__u64, mce_data_buf); + +static int ras_get_sensor_state_token; +static int ras_check_exception_token; + +#define EPOW_SENSOR_TOKEN 9 +#define EPOW_SENSOR_INDEX 0 + +static irqreturn_t ras_epow_interrupt(int irq, void *dev_id); +static irqreturn_t ras_error_interrupt(int irq, void *dev_id); + + +/* + * 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_event_sources_irqs(np, 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_event_sources_irqs(np, ras_epow_interrupt, "RAS_EPOW"); + of_node_put(np); + } + + return 0; +} +__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) +{ + 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, + RTAS_VECTOR_EXTERNAL_INTERRUPT, + virq_to_hw(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 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, + RTAS_VECTOR_EXTERNAL_INTERRUPT, + virq_to_hw(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_RTAS_POWER_OFF + /* 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; +} + +/* + * Some versions of FWNMI place the buffer inside the 4kB page starting at + * 0x7000. Other versions place it inside the rtas buffer. We check both. + */ +#define VALID_FWNMI_BUFFER(A) \ + ((((A) >= 0x7000) && ((A) < 0x7ff0)) || \ + (((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16)))) + +/* + * 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. + * + * If the RTAS error is not of the extended type, then we put it in a per + * cpu 64bit buffer. If it is the extended type we use global_mce_data_buf. + * + * The global_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 *savep; + struct rtas_error_log *h, *errhdr = NULL; + + if (!VALID_FWNMI_BUFFER(regs->gpr[3])) { + printk(KERN_ERR "FWNMI: corrupt r3 0x%016lx\n", regs->gpr[3]); + return NULL; + } + + savep = __va(regs->gpr[3]); + regs->gpr[3] = savep[0]; /* restore original r3 */ + + /* If it isn't an extended log we can use the per cpu 64bit buffer */ + h = (struct rtas_error_log *)&savep[1]; + if (!h->extended) { + memcpy(&__get_cpu_var(mce_data_buf), h, sizeof(__u64)); + errhdr = (struct rtas_error_log *)&__get_cpu_var(mce_data_buf); + } else { + int len; + + len = max_t(int, 8+h->extended_log_length, RTAS_ERROR_LOG_MAX); + memset(global_mce_data_buf, 0, RTAS_ERROR_LOG_MAX); + memcpy(global_mce_data_buf, h, len); + errhdr = (struct rtas_error_log *)global_mce_data_buf; + } + + 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(KERN_ERR "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 recovered = 0; + + if (!(regs->msr & MSR_RI)) { + /* If MSR_RI isn't set, we cannot recover */ + recovered = 0; + + } else if (err->disposition == RTAS_DISP_FULLY_RECOVERED) { + /* Platform corrected itself */ + recovered = 1; + + } else if (err->disposition == RTAS_DISP_LIMITED_RECOVERY) { + /* Platform corrected itself but could be degraded */ + printk(KERN_ERR "MCE: limited recovery, system may " + "be degraded\n"); + recovered = 1; + + } else if (user_mode(regs) && !is_global_init(current) && + err->severity == RTAS_SEVERITY_ERROR_SYNC) { + + /* + * If we received a synchronous error when in userspace + * kill the task. Firmware may report details of the fail + * asynchronously, so we can't rely on the target and type + * fields being valid here. + */ + printk(KERN_ERR "MCE: uncorrectable error, killing task " + "%s:%d\n", current->comm, current->pid); + + _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip); + recovered = 1; + } + + log_error((char *)err, ERR_TYPE_RTAS_LOG, 0); + + return recovered; +} + +/* + * 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; +} |