2 * Copyright (C) 2001 Dave Engebretsen IBM Corporation
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/sched.h>
20 #include <linux/interrupt.h>
21 #include <linux/irq.h>
24 #include <linux/reboot.h>
26 #include <asm/machdep.h>
28 #include <asm/firmware.h>
32 static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX];
33 static DEFINE_SPINLOCK(ras_log_buf_lock);
35 static char global_mce_data_buf[RTAS_ERROR_LOG_MAX];
36 static DEFINE_PER_CPU(__u64, mce_data_buf);
38 static int ras_check_exception_token;
40 #define EPOW_SENSOR_TOKEN 9
41 #define EPOW_SENSOR_INDEX 0
43 /* EPOW events counter variable */
44 static int num_epow_events;
46 static irqreturn_t ras_epow_interrupt(int irq, void *dev_id);
47 static irqreturn_t ras_error_interrupt(int irq, void *dev_id);
51 * Initialize handlers for the set of interrupts caused by hardware errors
52 * and power system events.
54 static int __init init_ras_IRQ(void)
56 struct device_node *np;
58 ras_check_exception_token = rtas_token("check-exception");
61 np = of_find_node_by_path("/event-sources/internal-errors");
63 request_event_sources_irqs(np, ras_error_interrupt,
69 np = of_find_node_by_path("/event-sources/epow-events");
71 request_event_sources_irqs(np, ras_epow_interrupt, "RAS_EPOW");
77 machine_subsys_initcall(pseries, init_ras_IRQ);
79 #define EPOW_SHUTDOWN_NORMAL 1
80 #define EPOW_SHUTDOWN_ON_UPS 2
81 #define EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS 3
82 #define EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH 4
84 static void handle_system_shutdown(char event_modifier)
86 switch (event_modifier) {
87 case EPOW_SHUTDOWN_NORMAL:
88 pr_emerg("Power off requested\n");
89 orderly_poweroff(true);
92 case EPOW_SHUTDOWN_ON_UPS:
93 pr_emerg("Loss of system power detected. System is running on"
94 " UPS/battery. Check RTAS error log for details\n");
95 orderly_poweroff(true);
98 case EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS:
99 pr_emerg("Loss of system critical functions detected. Check"
100 " RTAS error log for details\n");
101 orderly_poweroff(true);
104 case EPOW_SHUTDOWN_AMBIENT_TEMPERATURE_TOO_HIGH:
105 pr_emerg("High ambient temperature detected. Check RTAS"
106 " error log for details\n");
107 orderly_poweroff(true);
111 pr_err("Unknown power/cooling shutdown event (modifier = %d)\n",
116 struct epow_errorlog {
117 unsigned char sensor_value;
118 unsigned char event_modifier;
119 unsigned char extended_modifier;
120 unsigned char reserved;
121 unsigned char platform_reason;
125 #define EPOW_WARN_COOLING 1
126 #define EPOW_WARN_POWER 2
127 #define EPOW_SYSTEM_SHUTDOWN 3
128 #define EPOW_SYSTEM_HALT 4
129 #define EPOW_MAIN_ENCLOSURE 5
130 #define EPOW_POWER_OFF 7
132 static void rtas_parse_epow_errlog(struct rtas_error_log *log)
134 struct pseries_errorlog *pseries_log;
135 struct epow_errorlog *epow_log;
139 pseries_log = get_pseries_errorlog(log, PSERIES_ELOG_SECT_ID_EPOW);
140 if (pseries_log == NULL)
143 epow_log = (struct epow_errorlog *)pseries_log->data;
144 action_code = epow_log->sensor_value & 0xF; /* bottom 4 bits */
145 modifier = epow_log->event_modifier & 0xF; /* bottom 4 bits */
147 switch (action_code) {
149 if (num_epow_events) {
150 pr_info("Non critical power/cooling issue cleared\n");
155 case EPOW_WARN_COOLING:
156 pr_info("Non-critical cooling issue detected. Check RTAS error"
157 " log for details\n");
160 case EPOW_WARN_POWER:
161 pr_info("Non-critical power issue detected. Check RTAS error"
162 " log for details\n");
165 case EPOW_SYSTEM_SHUTDOWN:
166 handle_system_shutdown(epow_log->event_modifier);
169 case EPOW_SYSTEM_HALT:
170 pr_emerg("Critical power/cooling issue detected. Check RTAS"
171 " error log for details. Powering off.\n");
172 orderly_poweroff(true);
175 case EPOW_MAIN_ENCLOSURE:
177 pr_emerg("System about to lose power. Check RTAS error log "
178 " for details. Powering off immediately.\n");
184 pr_err("Unknown power/cooling event (action code = %d)\n",
188 /* Increment epow events counter variable */
189 if (action_code != EPOW_RESET)
193 /* Handle environmental and power warning (EPOW) interrupts. */
194 static irqreturn_t ras_epow_interrupt(int irq, void *dev_id)
200 status = rtas_get_sensor_fast(EPOW_SENSOR_TOKEN, EPOW_SENSOR_INDEX,
204 critical = 1; /* Time Critical */
208 spin_lock(&ras_log_buf_lock);
210 status = rtas_call(ras_check_exception_token, 6, 1, NULL,
211 RTAS_VECTOR_EXTERNAL_INTERRUPT,
214 critical, __pa(&ras_log_buf),
215 rtas_get_error_log_max());
217 log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0);
219 rtas_parse_epow_errlog((struct rtas_error_log *)ras_log_buf);
221 spin_unlock(&ras_log_buf_lock);
226 * Handle hardware error interrupts.
228 * RTAS check-exception is called to collect data on the exception. If
229 * the error is deemed recoverable, we log a warning and return.
230 * For nonrecoverable errors, an error is logged and we stop all processing
231 * as quickly as possible in order to prevent propagation of the failure.
233 static irqreturn_t ras_error_interrupt(int irq, void *dev_id)
235 struct rtas_error_log *rtas_elog;
239 spin_lock(&ras_log_buf_lock);
241 status = rtas_call(ras_check_exception_token, 6, 1, NULL,
242 RTAS_VECTOR_EXTERNAL_INTERRUPT,
244 RTAS_INTERNAL_ERROR, 1 /* Time Critical */,
246 rtas_get_error_log_max());
248 rtas_elog = (struct rtas_error_log *)ras_log_buf;
251 rtas_error_severity(rtas_elog) >= RTAS_SEVERITY_ERROR_SYNC)
256 /* format and print the extended information */
257 log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, fatal);
260 pr_emerg("Fatal hardware error detected. Check RTAS error"
261 " log for details. Powering off immediately\n");
265 pr_err("Recoverable hardware error detected\n");
268 spin_unlock(&ras_log_buf_lock);
273 * Some versions of FWNMI place the buffer inside the 4kB page starting at
274 * 0x7000. Other versions place it inside the rtas buffer. We check both.
276 #define VALID_FWNMI_BUFFER(A) \
277 ((((A) >= 0x7000) && ((A) < 0x7ff0)) || \
278 (((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16))))
281 * Get the error information for errors coming through the
282 * FWNMI vectors. The pt_regs' r3 will be updated to reflect
283 * the actual r3 if possible, and a ptr to the error log entry
284 * will be returned if found.
286 * If the RTAS error is not of the extended type, then we put it in a per
287 * cpu 64bit buffer. If it is the extended type we use global_mce_data_buf.
289 * The global_mce_data_buf does not have any locks or protection around it,
290 * if a second machine check comes in, or a system reset is done
291 * before we have logged the error, then we will get corruption in the
292 * error log. This is preferable over holding off on calling
293 * ibm,nmi-interlock which would result in us checkstopping if a
294 * second machine check did come in.
296 static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
298 unsigned long *savep;
299 struct rtas_error_log *h, *errhdr = NULL;
301 /* Mask top two bits */
302 regs->gpr[3] &= ~(0x3UL << 62);
304 if (!VALID_FWNMI_BUFFER(regs->gpr[3])) {
305 printk(KERN_ERR "FWNMI: corrupt r3 0x%016lx\n", regs->gpr[3]);
309 savep = __va(regs->gpr[3]);
310 regs->gpr[3] = savep[0]; /* restore original r3 */
312 /* If it isn't an extended log we can use the per cpu 64bit buffer */
313 h = (struct rtas_error_log *)&savep[1];
314 if (!rtas_error_extended(h)) {
315 memcpy(this_cpu_ptr(&mce_data_buf), h, sizeof(__u64));
316 errhdr = (struct rtas_error_log *)this_cpu_ptr(&mce_data_buf);
318 int len, error_log_length;
320 error_log_length = 8 + rtas_error_extended_log_length(h);
321 len = max_t(int, error_log_length, RTAS_ERROR_LOG_MAX);
322 memset(global_mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
323 memcpy(global_mce_data_buf, h, len);
324 errhdr = (struct rtas_error_log *)global_mce_data_buf;
330 /* Call this when done with the data returned by FWNMI_get_errinfo.
331 * It will release the saved data area for other CPUs in the
332 * partition to receive FWNMI errors.
334 static void fwnmi_release_errinfo(void)
336 int ret = rtas_call(rtas_token("ibm,nmi-interlock"), 0, 1, NULL);
338 printk(KERN_ERR "FWNMI: nmi-interlock failed: %d\n", ret);
341 int pSeries_system_reset_exception(struct pt_regs *regs)
344 struct rtas_error_log *errhdr = fwnmi_get_errinfo(regs);
346 /* XXX Should look at FWNMI information */
348 fwnmi_release_errinfo();
350 return 0; /* need to perform reset */
354 * See if we can recover from a machine check exception.
355 * This is only called on power4 (or above) and only via
356 * the Firmware Non-Maskable Interrupts (fwnmi) handler
357 * which provides the error analysis for us.
359 * Return 1 if corrected (or delivered a signal).
360 * Return 0 if there is nothing we can do.
362 static int recover_mce(struct pt_regs *regs, struct rtas_error_log *err)
365 int disposition = rtas_error_disposition(err);
367 if (!(regs->msr & MSR_RI)) {
368 /* If MSR_RI isn't set, we cannot recover */
371 } else if (disposition == RTAS_DISP_FULLY_RECOVERED) {
372 /* Platform corrected itself */
375 } else if (disposition == RTAS_DISP_LIMITED_RECOVERY) {
376 /* Platform corrected itself but could be degraded */
377 printk(KERN_ERR "MCE: limited recovery, system may "
381 } else if (user_mode(regs) && !is_global_init(current) &&
382 rtas_error_severity(err) == RTAS_SEVERITY_ERROR_SYNC) {
385 * If we received a synchronous error when in userspace
386 * kill the task. Firmware may report details of the fail
387 * asynchronously, so we can't rely on the target and type
388 * fields being valid here.
390 printk(KERN_ERR "MCE: uncorrectable error, killing task "
391 "%s:%d\n", current->comm, current->pid);
393 _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
397 log_error((char *)err, ERR_TYPE_RTAS_LOG, 0);
403 * Handle a machine check.
405 * Note that on Power 4 and beyond Firmware Non-Maskable Interrupts (fwnmi)
406 * should be present. If so the handler which called us tells us if the
407 * error was recovered (never true if RI=0).
409 * On hardware prior to Power 4 these exceptions were asynchronous which
410 * means we can't tell exactly where it occurred and so we can't recover.
412 int pSeries_machine_check_exception(struct pt_regs *regs)
414 struct rtas_error_log *errp;
417 errp = fwnmi_get_errinfo(regs);
418 fwnmi_release_errinfo();
419 if (errp && recover_mce(regs, errp))