| /* |
| * 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, |
| irq_map[irq].hwirq, |
| 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, |
| irq_map[irq].hwirq, |
| 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\n"); |
| 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; |
| } |