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Diffstat (limited to '')
| -rw-r--r-- | arch/powerpc/platforms/pseries/ras.c | 513 |
1 files changed, 513 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c new file mode 100644 index 000000000..e82710868 --- /dev/null +++ b/arch/powerpc/platforms/pseries/ras.c @@ -0,0 +1,513 @@ +/* + * 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 + */ + +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/of.h> +#include <linux/fs.h> +#include <linux/reboot.h> +#include <linux/irq_work.h> + +#include <asm/machdep.h> +#include <asm/rtas.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 int ras_check_exception_token; + +static void mce_process_errlog_event(struct irq_work *work); +static struct irq_work mce_errlog_process_work = { + .func = mce_process_errlog_event, +}; + +#define EPOW_SENSOR_TOKEN 9 +#define EPOW_SENSOR_INDEX 0 + +/* EPOW events counter variable */ +static int num_epow_events; + +static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id); +static irqreturn_t ras_epow_interrupt(int irq, void *dev_id); +static irqreturn_t ras_error_interrupt(int irq, void *dev_id); + + +/* + * Enable the hotplug interrupt late because processing them may touch other + * devices or systems (e.g. hugepages) that have not been initialized at the + * subsys stage. + */ +int __init init_ras_hotplug_IRQ(void) +{ + struct device_node *np; + + /* Hotplug Events */ + np = of_find_node_by_path("/event-sources/hot-plug-events"); + if (np != NULL) { + if (dlpar_workqueue_init() == 0) + request_event_sources_irqs(np, ras_hotplug_interrupt, + "RAS_HOTPLUG"); + of_node_put(np); + } + + return 0; +} +machine_late_initcall(pseries, init_ras_hotplug_IRQ); + +/* + * 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_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; +} +machine_subsys_initcall(pseries, init_ras_IRQ); + +#define EPOW_SHUTDOWN_NORMAL 1 +#define EPOW_SHUTDOWN_ON_UPS 2 +#define EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS 3 +#define EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH 4 + +static void handle_system_shutdown(char event_modifier) +{ + switch (event_modifier) { + case EPOW_SHUTDOWN_NORMAL: + pr_emerg("Power off requested\n"); + orderly_poweroff(true); + break; + + case EPOW_SHUTDOWN_ON_UPS: + pr_emerg("Loss of system power detected. System is running on" + " UPS/battery. Check RTAS error log for details\n"); + break; + + case EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS: + pr_emerg("Loss of system critical functions detected. Check" + " RTAS error log for details\n"); + orderly_poweroff(true); + break; + + case EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH: + pr_emerg("High ambient temperature detected. Check RTAS" + " error log for details\n"); + orderly_poweroff(true); + break; + + default: + pr_err("Unknown power/cooling shutdown event (modifier = %d)\n", + event_modifier); + } +} + +struct epow_errorlog { + unsigned char sensor_value; + unsigned char event_modifier; + unsigned char extended_modifier; + unsigned char reserved; + unsigned char platform_reason; +}; + +#define EPOW_RESET 0 +#define EPOW_WARN_COOLING 1 +#define EPOW_WARN_POWER 2 +#define EPOW_SYSTEM_SHUTDOWN 3 +#define EPOW_SYSTEM_HALT 4 +#define EPOW_MAIN_ENCLOSURE 5 +#define EPOW_POWER_OFF 7 + +static void rtas_parse_epow_errlog(struct rtas_error_log *log) +{ + struct pseries_errorlog *pseries_log; + struct epow_errorlog *epow_log; + char action_code; + char modifier; + + pseries_log = get_pseries_errorlog(log, PSERIES_ELOG_SECT_ID_EPOW); + if (pseries_log == NULL) + return; + + epow_log = (struct epow_errorlog *)pseries_log->data; + action_code = epow_log->sensor_value & 0xF; /* bottom 4 bits */ + modifier = epow_log->event_modifier & 0xF; /* bottom 4 bits */ + + switch (action_code) { + case EPOW_RESET: + if (num_epow_events) { + pr_info("Non critical power/cooling issue cleared\n"); + num_epow_events--; + } + break; + + case EPOW_WARN_COOLING: + pr_info("Non-critical cooling issue detected. Check RTAS error" + " log for details\n"); + break; + + case EPOW_WARN_POWER: + pr_info("Non-critical power issue detected. Check RTAS error" + " log for details\n"); + break; + + case EPOW_SYSTEM_SHUTDOWN: + handle_system_shutdown(epow_log->event_modifier); + break; + + case EPOW_SYSTEM_HALT: + pr_emerg("Critical power/cooling issue detected. Check RTAS" + " error log for details. Powering off.\n"); + orderly_poweroff(true); + break; + + case EPOW_MAIN_ENCLOSURE: + case EPOW_POWER_OFF: + pr_emerg("System about to lose power. Check RTAS error log " + " for details. Powering off immediately.\n"); + emergency_sync(); + kernel_power_off(); + break; + + default: + pr_err("Unknown power/cooling event (action code = %d)\n", + action_code); + } + + /* Increment epow events counter variable */ + if (action_code != EPOW_RESET) + num_epow_events++; +} + +static irqreturn_t ras_hotplug_interrupt(int irq, void *dev_id) +{ + struct pseries_errorlog *pseries_log; + struct pseries_hp_errorlog *hp_elog; + + spin_lock(&ras_log_buf_lock); + + rtas_call(ras_check_exception_token, 6, 1, NULL, + RTAS_VECTOR_EXTERNAL_INTERRUPT, virq_to_hw(irq), + RTAS_HOTPLUG_EVENTS, 0, __pa(&ras_log_buf), + rtas_get_error_log_max()); + + pseries_log = get_pseries_errorlog((struct rtas_error_log *)ras_log_buf, + PSERIES_ELOG_SECT_ID_HOTPLUG); + hp_elog = (struct pseries_hp_errorlog *)pseries_log->data; + + /* + * Since PCI hotplug is not currently supported on pseries, put PCI + * hotplug events on the ras_log_buf to be handled by rtas_errd. + */ + if (hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_MEM || + hp_elog->resource == PSERIES_HP_ELOG_RESOURCE_CPU) + queue_hotplug_event(hp_elog, NULL, NULL); + else + log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0); + + spin_unlock(&ras_log_buf_lock); + return IRQ_HANDLED; +} + +/* Handle environmental and power warning (EPOW) interrupts. */ +static irqreturn_t ras_epow_interrupt(int irq, void *dev_id) +{ + int status; + int state; + int critical; + + status = rtas_get_sensor_fast(EPOW_SENSOR_TOKEN, EPOW_SENSOR_INDEX, + &state); + + 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, + critical, __pa(&ras_log_buf), + rtas_get_error_log_max()); + + log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0); + + rtas_parse_epow_errlog((struct rtas_error_log *)ras_log_buf); + + 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; + 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_error_severity(rtas_elog) >= 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) { + pr_emerg("Fatal hardware error detected. Check RTAS error" + " log for details. Powering off immediately\n"); + emergency_sync(); + kernel_power_off(); + } else { + pr_err("Recoverable hardware error detected\n"); + } + + 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. + * Minimum size of the buffer is 16 bytes. + */ +#define VALID_FWNMI_BUFFER(A) \ + ((((A) >= 0x7000) && ((A) <= 0x8000 - 16)) || \ + (((A) >= rtas.base) && ((A) <= (rtas.base + rtas.size - 16)))) + +static inline struct rtas_error_log *fwnmi_get_errlog(void) +{ + return (struct rtas_error_log *)local_paca->mce_data_buf; +} + +/* + * 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. + * + * Use one buffer mce_data_buf per cpu to store RTAS error. + * + * 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 *savep; + struct rtas_error_log *h; + + /* Mask top two bits */ + regs->gpr[3] &= ~(0x3UL << 62); + + 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] = be64_to_cpu(savep[0]); /* restore original r3 */ + + h = (struct rtas_error_log *)&savep[1]; + /* Use the per cpu buffer from paca to store rtas error log */ + memset(local_paca->mce_data_buf, 0, RTAS_ERROR_LOG_MAX); + if (!rtas_error_extended(h)) { + memcpy(local_paca->mce_data_buf, h, sizeof(__u64)); + } else { + int len, error_log_length; + + error_log_length = 8 + rtas_error_extended_log_length(h); + len = min_t(int, error_log_length, RTAS_ERROR_LOG_MAX); + memcpy(local_paca->mce_data_buf, h, len); + } + + return (struct rtas_error_log *)local_paca->mce_data_buf; +} + +/* 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) +{ +#ifdef __LITTLE_ENDIAN__ + /* + * Some firmware byteswaps SRR registers and gives incorrect SRR1. Try + * to detect the bad SRR1 pattern here. Flip the NIP back to correct + * endian for reporting purposes. Unfortunately the MSR can't be fixed, + * so clear it. It will be missing MSR_RI so we won't try to recover. + */ + if ((be64_to_cpu(regs->msr) & + (MSR_LE|MSR_RI|MSR_DR|MSR_IR|MSR_ME|MSR_PR| + MSR_ILE|MSR_HV|MSR_SF)) == (MSR_DR|MSR_SF)) { + regs->nip = be64_to_cpu((__be64)regs->nip); + regs->msr = 0; + } +#endif + + if (fwnmi_active) { + struct rtas_error_log *errhdr = fwnmi_get_errinfo(regs); + if (errhdr) { + /* XXX Should look at FWNMI information */ + } + fwnmi_release_errinfo(); + } + + if (smp_handle_nmi_ipi(regs)) + return 1; + + return 0; /* need to perform reset */ +} + +/* + * Process MCE rtas errlog event. + */ +static void mce_process_errlog_event(struct irq_work *work) +{ + struct rtas_error_log *err; + + err = fwnmi_get_errlog(); + log_error((char *)err, ERR_TYPE_RTAS_LOG, 0); +} + +/* + * 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; + int disposition = rtas_error_disposition(err); + + if (!(regs->msr & MSR_RI)) { + /* If MSR_RI isn't set, we cannot recover */ + recovered = 0; + + } else if (disposition == RTAS_DISP_FULLY_RECOVERED) { + /* Platform corrected itself */ + recovered = 1; + + } else if (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) && + rtas_error_severity(err) == 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; + } + + /* Queue irq work to log this rtas event later. */ + irq_work_queue(&mce_errlog_process_work); + + 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; +} |