Merge tag 'atlas7-pinctrl-dts-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel...
[pandora-kernel.git] / arch / powerpc / platforms / powernv / opal.c
1 /*
2  * PowerNV OPAL high level interfaces
3  *
4  * Copyright 2011 IBM Corp.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11
12 #define pr_fmt(fmt)     "opal: " fmt
13
14 #include <linux/printk.h>
15 #include <linux/types.h>
16 #include <linux/of.h>
17 #include <linux/of_fdt.h>
18 #include <linux/of_platform.h>
19 #include <linux/interrupt.h>
20 #include <linux/notifier.h>
21 #include <linux/slab.h>
22 #include <linux/sched.h>
23 #include <linux/kobject.h>
24 #include <linux/delay.h>
25 #include <linux/memblock.h>
26 #include <linux/kthread.h>
27 #include <linux/freezer.h>
28
29 #include <asm/machdep.h>
30 #include <asm/opal.h>
31 #include <asm/firmware.h>
32 #include <asm/mce.h>
33
34 #include "powernv.h"
35
36 /* /sys/firmware/opal */
37 struct kobject *opal_kobj;
38
39 struct opal {
40         u64 base;
41         u64 entry;
42         u64 size;
43 } opal;
44
45 struct mcheck_recoverable_range {
46         u64 start_addr;
47         u64 end_addr;
48         u64 recover_addr;
49 };
50
51 static struct mcheck_recoverable_range *mc_recoverable_range;
52 static int mc_recoverable_range_len;
53
54 struct device_node *opal_node;
55 static DEFINE_SPINLOCK(opal_write_lock);
56 static struct atomic_notifier_head opal_msg_notifier_head[OPAL_MSG_TYPE_MAX];
57 static uint32_t opal_heartbeat;
58
59 static void opal_reinit_cores(void)
60 {
61         /* Do the actual re-init, This will clobber all FPRs, VRs, etc...
62          *
63          * It will preserve non volatile GPRs and HSPRG0/1. It will
64          * also restore HIDs and other SPRs to their original value
65          * but it might clobber a bunch.
66          */
67 #ifdef __BIG_ENDIAN__
68         opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_BE);
69 #else
70         opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_LE);
71 #endif
72 }
73
74 int __init early_init_dt_scan_opal(unsigned long node,
75                                    const char *uname, int depth, void *data)
76 {
77         const void *basep, *entryp, *sizep;
78         int basesz, entrysz, runtimesz;
79
80         if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
81                 return 0;
82
83         basep  = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
84         entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
85         sizep = of_get_flat_dt_prop(node, "opal-runtime-size", &runtimesz);
86
87         if (!basep || !entryp || !sizep)
88                 return 1;
89
90         opal.base = of_read_number(basep, basesz/4);
91         opal.entry = of_read_number(entryp, entrysz/4);
92         opal.size = of_read_number(sizep, runtimesz/4);
93
94         pr_debug("OPAL Base  = 0x%llx (basep=%p basesz=%d)\n",
95                  opal.base, basep, basesz);
96         pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%d)\n",
97                  opal.entry, entryp, entrysz);
98         pr_debug("OPAL Entry = 0x%llx (sizep=%p runtimesz=%d)\n",
99                  opal.size, sizep, runtimesz);
100
101         powerpc_firmware_features |= FW_FEATURE_OPAL;
102         if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) {
103                 powerpc_firmware_features |= FW_FEATURE_OPALv2;
104                 powerpc_firmware_features |= FW_FEATURE_OPALv3;
105                 pr_info("OPAL V3 detected !\n");
106         } else if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
107                 powerpc_firmware_features |= FW_FEATURE_OPALv2;
108                 pr_info("OPAL V2 detected !\n");
109         } else {
110                 pr_info("OPAL V1 detected !\n");
111         }
112
113         /* Reinit all cores with the right endian */
114         opal_reinit_cores();
115
116         /* Restore some bits */
117         if (cur_cpu_spec->cpu_restore)
118                 cur_cpu_spec->cpu_restore();
119
120         return 1;
121 }
122
123 int __init early_init_dt_scan_recoverable_ranges(unsigned long node,
124                                    const char *uname, int depth, void *data)
125 {
126         int i, psize, size;
127         const __be32 *prop;
128
129         if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
130                 return 0;
131
132         prop = of_get_flat_dt_prop(node, "mcheck-recoverable-ranges", &psize);
133
134         if (!prop)
135                 return 1;
136
137         pr_debug("Found machine check recoverable ranges.\n");
138
139         /*
140          * Calculate number of available entries.
141          *
142          * Each recoverable address range entry is (start address, len,
143          * recovery address), 2 cells each for start and recovery address,
144          * 1 cell for len, totalling 5 cells per entry.
145          */
146         mc_recoverable_range_len = psize / (sizeof(*prop) * 5);
147
148         /* Sanity check */
149         if (!mc_recoverable_range_len)
150                 return 1;
151
152         /* Size required to hold all the entries. */
153         size = mc_recoverable_range_len *
154                         sizeof(struct mcheck_recoverable_range);
155
156         /*
157          * Allocate a buffer to hold the MC recoverable ranges. We would be
158          * accessing them in real mode, hence it needs to be within
159          * RMO region.
160          */
161         mc_recoverable_range =__va(memblock_alloc_base(size, __alignof__(u64),
162                                                         ppc64_rma_size));
163         memset(mc_recoverable_range, 0, size);
164
165         for (i = 0; i < mc_recoverable_range_len; i++) {
166                 mc_recoverable_range[i].start_addr =
167                                         of_read_number(prop + (i * 5) + 0, 2);
168                 mc_recoverable_range[i].end_addr =
169                                         mc_recoverable_range[i].start_addr +
170                                         of_read_number(prop + (i * 5) + 2, 1);
171                 mc_recoverable_range[i].recover_addr =
172                                         of_read_number(prop + (i * 5) + 3, 2);
173
174                 pr_debug("Machine check recoverable range: %llx..%llx: %llx\n",
175                                 mc_recoverable_range[i].start_addr,
176                                 mc_recoverable_range[i].end_addr,
177                                 mc_recoverable_range[i].recover_addr);
178         }
179         return 1;
180 }
181
182 static int __init opal_register_exception_handlers(void)
183 {
184 #ifdef __BIG_ENDIAN__
185         u64 glue;
186
187         if (!(powerpc_firmware_features & FW_FEATURE_OPAL))
188                 return -ENODEV;
189
190         /* Hookup some exception handlers except machine check. We use the
191          * fwnmi area at 0x7000 to provide the glue space to OPAL
192          */
193         glue = 0x7000;
194
195         /*
196          * Check if we are running on newer firmware that exports
197          * OPAL_HANDLE_HMI token. If yes, then don't ask OPAL to patch
198          * the HMI interrupt and we catch it directly in Linux.
199          *
200          * For older firmware (i.e currently released POWER8 System Firmware
201          * as of today <= SV810_087), we fallback to old behavior and let OPAL
202          * patch the HMI vector and handle it inside OPAL firmware.
203          *
204          * For newer firmware (in development/yet to be released) we will
205          * start catching/handling HMI directly in Linux.
206          */
207         if (!opal_check_token(OPAL_HANDLE_HMI)) {
208                 pr_info("Old firmware detected, OPAL handles HMIs.\n");
209                 opal_register_exception_handler(
210                                 OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
211                                 0, glue);
212                 glue += 128;
213         }
214
215         opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
216 #endif
217
218         return 0;
219 }
220 machine_early_initcall(powernv, opal_register_exception_handlers);
221
222 /*
223  * Opal message notifier based on message type. Allow subscribers to get
224  * notified for specific messgae type.
225  */
226 int opal_message_notifier_register(enum opal_msg_type msg_type,
227                                         struct notifier_block *nb)
228 {
229         if (!nb || msg_type >= OPAL_MSG_TYPE_MAX) {
230                 pr_warning("%s: Invalid arguments, msg_type:%d\n",
231                            __func__, msg_type);
232                 return -EINVAL;
233         }
234
235         return atomic_notifier_chain_register(
236                                 &opal_msg_notifier_head[msg_type], nb);
237 }
238 EXPORT_SYMBOL_GPL(opal_message_notifier_register);
239
240 int opal_message_notifier_unregister(enum opal_msg_type msg_type,
241                                      struct notifier_block *nb)
242 {
243         return atomic_notifier_chain_unregister(
244                         &opal_msg_notifier_head[msg_type], nb);
245 }
246 EXPORT_SYMBOL_GPL(opal_message_notifier_unregister);
247
248 static void opal_message_do_notify(uint32_t msg_type, void *msg)
249 {
250         /* notify subscribers */
251         atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
252                                         msg_type, msg);
253 }
254
255 static void opal_handle_message(void)
256 {
257         s64 ret;
258         /*
259          * TODO: pre-allocate a message buffer depending on opal-msg-size
260          * value in /proc/device-tree.
261          */
262         static struct opal_msg msg;
263         u32 type;
264
265         ret = opal_get_msg(__pa(&msg), sizeof(msg));
266         /* No opal message pending. */
267         if (ret == OPAL_RESOURCE)
268                 return;
269
270         /* check for errors. */
271         if (ret) {
272                 pr_warning("%s: Failed to retrieve opal message, err=%lld\n",
273                                 __func__, ret);
274                 return;
275         }
276
277         type = be32_to_cpu(msg.msg_type);
278
279         /* Sanity check */
280         if (type >= OPAL_MSG_TYPE_MAX) {
281                 pr_warning("%s: Unknown message type: %u\n", __func__, type);
282                 return;
283         }
284         opal_message_do_notify(type, (void *)&msg);
285 }
286
287 static irqreturn_t opal_message_notify(int irq, void *data)
288 {
289         opal_handle_message();
290         return IRQ_HANDLED;
291 }
292
293 static int __init opal_message_init(void)
294 {
295         int ret, i, irq;
296
297         for (i = 0; i < OPAL_MSG_TYPE_MAX; i++)
298                 ATOMIC_INIT_NOTIFIER_HEAD(&opal_msg_notifier_head[i]);
299
300         irq = opal_event_request(ilog2(OPAL_EVENT_MSG_PENDING));
301         if (!irq) {
302                 pr_err("%s: Can't register OPAL event irq (%d)\n",
303                        __func__, irq);
304                 return irq;
305         }
306
307         ret = request_irq(irq, opal_message_notify,
308                         IRQ_TYPE_LEVEL_HIGH, "opal-msg", NULL);
309         if (ret) {
310                 pr_err("%s: Can't request OPAL event irq (%d)\n",
311                        __func__, ret);
312                 return ret;
313         }
314
315         return 0;
316 }
317
318 int opal_get_chars(uint32_t vtermno, char *buf, int count)
319 {
320         s64 rc;
321         __be64 evt, len;
322
323         if (!opal.entry)
324                 return -ENODEV;
325         opal_poll_events(&evt);
326         if ((be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_INPUT) == 0)
327                 return 0;
328         len = cpu_to_be64(count);
329         rc = opal_console_read(vtermno, &len, buf);
330         if (rc == OPAL_SUCCESS)
331                 return be64_to_cpu(len);
332         return 0;
333 }
334
335 int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
336 {
337         int written = 0;
338         __be64 olen;
339         s64 len, rc;
340         unsigned long flags;
341         __be64 evt;
342
343         if (!opal.entry)
344                 return -ENODEV;
345
346         /* We want put_chars to be atomic to avoid mangling of hvsi
347          * packets. To do that, we first test for room and return
348          * -EAGAIN if there isn't enough.
349          *
350          * Unfortunately, opal_console_write_buffer_space() doesn't
351          * appear to work on opal v1, so we just assume there is
352          * enough room and be done with it
353          */
354         spin_lock_irqsave(&opal_write_lock, flags);
355         if (firmware_has_feature(FW_FEATURE_OPALv2)) {
356                 rc = opal_console_write_buffer_space(vtermno, &olen);
357                 len = be64_to_cpu(olen);
358                 if (rc || len < total_len) {
359                         spin_unlock_irqrestore(&opal_write_lock, flags);
360                         /* Closed -> drop characters */
361                         if (rc)
362                                 return total_len;
363                         opal_poll_events(NULL);
364                         return -EAGAIN;
365                 }
366         }
367
368         /* We still try to handle partial completions, though they
369          * should no longer happen.
370          */
371         rc = OPAL_BUSY;
372         while(total_len > 0 && (rc == OPAL_BUSY ||
373                                 rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
374                 olen = cpu_to_be64(total_len);
375                 rc = opal_console_write(vtermno, &olen, data);
376                 len = be64_to_cpu(olen);
377
378                 /* Closed or other error drop */
379                 if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
380                     rc != OPAL_BUSY_EVENT) {
381                         written = total_len;
382                         break;
383                 }
384                 if (rc == OPAL_SUCCESS) {
385                         total_len -= len;
386                         data += len;
387                         written += len;
388                 }
389                 /* This is a bit nasty but we need that for the console to
390                  * flush when there aren't any interrupts. We will clean
391                  * things a bit later to limit that to synchronous path
392                  * such as the kernel console and xmon/udbg
393                  */
394                 do
395                         opal_poll_events(&evt);
396                 while(rc == OPAL_SUCCESS &&
397                         (be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT));
398         }
399         spin_unlock_irqrestore(&opal_write_lock, flags);
400         return written;
401 }
402
403 static int opal_recover_mce(struct pt_regs *regs,
404                                         struct machine_check_event *evt)
405 {
406         int recovered = 0;
407         uint64_t ea = get_mce_fault_addr(evt);
408
409         if (!(regs->msr & MSR_RI)) {
410                 /* If MSR_RI isn't set, we cannot recover */
411                 recovered = 0;
412         } else if (evt->disposition == MCE_DISPOSITION_RECOVERED) {
413                 /* Platform corrected itself */
414                 recovered = 1;
415         } else if (ea && !is_kernel_addr(ea)) {
416                 /*
417                  * Faulting address is not in kernel text. We should be fine.
418                  * We need to find which process uses this address.
419                  * For now, kill the task if we have received exception when
420                  * in userspace.
421                  *
422                  * TODO: Queue up this address for hwpoisioning later.
423                  */
424                 if (user_mode(regs) && !is_global_init(current)) {
425                         _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
426                         recovered = 1;
427                 } else
428                         recovered = 0;
429         } else if (user_mode(regs) && !is_global_init(current) &&
430                 evt->severity == MCE_SEV_ERROR_SYNC) {
431                 /*
432                  * If we have received a synchronous error when in userspace
433                  * kill the task.
434                  */
435                 _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
436                 recovered = 1;
437         }
438         return recovered;
439 }
440
441 int opal_machine_check(struct pt_regs *regs)
442 {
443         struct machine_check_event evt;
444
445         if (!get_mce_event(&evt, MCE_EVENT_RELEASE))
446                 return 0;
447
448         /* Print things out */
449         if (evt.version != MCE_V1) {
450                 pr_err("Machine Check Exception, Unknown event version %d !\n",
451                        evt.version);
452                 return 0;
453         }
454         machine_check_print_event_info(&evt);
455
456         if (opal_recover_mce(regs, &evt))
457                 return 1;
458         return 0;
459 }
460
461 /* Early hmi handler called in real mode. */
462 int opal_hmi_exception_early(struct pt_regs *regs)
463 {
464         s64 rc;
465
466         /*
467          * call opal hmi handler. Pass paca address as token.
468          * The return value OPAL_SUCCESS is an indication that there is
469          * an HMI event generated waiting to pull by Linux.
470          */
471         rc = opal_handle_hmi();
472         if (rc == OPAL_SUCCESS) {
473                 local_paca->hmi_event_available = 1;
474                 return 1;
475         }
476         return 0;
477 }
478
479 /* HMI exception handler called in virtual mode during check_irq_replay. */
480 int opal_handle_hmi_exception(struct pt_regs *regs)
481 {
482         s64 rc;
483         __be64 evt = 0;
484
485         /*
486          * Check if HMI event is available.
487          * if Yes, then call opal_poll_events to pull opal messages and
488          * process them.
489          */
490         if (!local_paca->hmi_event_available)
491                 return 0;
492
493         local_paca->hmi_event_available = 0;
494         rc = opal_poll_events(&evt);
495         if (rc == OPAL_SUCCESS && evt)
496                 opal_handle_events(be64_to_cpu(evt));
497
498         return 1;
499 }
500
501 static uint64_t find_recovery_address(uint64_t nip)
502 {
503         int i;
504
505         for (i = 0; i < mc_recoverable_range_len; i++)
506                 if ((nip >= mc_recoverable_range[i].start_addr) &&
507                     (nip < mc_recoverable_range[i].end_addr))
508                     return mc_recoverable_range[i].recover_addr;
509         return 0;
510 }
511
512 bool opal_mce_check_early_recovery(struct pt_regs *regs)
513 {
514         uint64_t recover_addr = 0;
515
516         if (!opal.base || !opal.size)
517                 goto out;
518
519         if ((regs->nip >= opal.base) &&
520                         (regs->nip <= (opal.base + opal.size)))
521                 recover_addr = find_recovery_address(regs->nip);
522
523         /*
524          * Setup regs->nip to rfi into fixup address.
525          */
526         if (recover_addr)
527                 regs->nip = recover_addr;
528
529 out:
530         return !!recover_addr;
531 }
532
533 static int opal_sysfs_init(void)
534 {
535         opal_kobj = kobject_create_and_add("opal", firmware_kobj);
536         if (!opal_kobj) {
537                 pr_warn("kobject_create_and_add opal failed\n");
538                 return -ENOMEM;
539         }
540
541         return 0;
542 }
543
544 static ssize_t symbol_map_read(struct file *fp, struct kobject *kobj,
545                                struct bin_attribute *bin_attr,
546                                char *buf, loff_t off, size_t count)
547 {
548         return memory_read_from_buffer(buf, count, &off, bin_attr->private,
549                                        bin_attr->size);
550 }
551
552 static BIN_ATTR_RO(symbol_map, 0);
553
554 static void opal_export_symmap(void)
555 {
556         const __be64 *syms;
557         unsigned int size;
558         struct device_node *fw;
559         int rc;
560
561         fw = of_find_node_by_path("/ibm,opal/firmware");
562         if (!fw)
563                 return;
564         syms = of_get_property(fw, "symbol-map", &size);
565         if (!syms || size != 2 * sizeof(__be64))
566                 return;
567
568         /* Setup attributes */
569         bin_attr_symbol_map.private = __va(be64_to_cpu(syms[0]));
570         bin_attr_symbol_map.size = be64_to_cpu(syms[1]);
571
572         rc = sysfs_create_bin_file(opal_kobj, &bin_attr_symbol_map);
573         if (rc)
574                 pr_warn("Error %d creating OPAL symbols file\n", rc);
575 }
576
577 static void __init opal_dump_region_init(void)
578 {
579         void *addr;
580         uint64_t size;
581         int rc;
582
583         if (!opal_check_token(OPAL_REGISTER_DUMP_REGION))
584                 return;
585
586         /* Register kernel log buffer */
587         addr = log_buf_addr_get();
588         if (addr == NULL)
589                 return;
590
591         size = log_buf_len_get();
592         if (size == 0)
593                 return;
594
595         rc = opal_register_dump_region(OPAL_DUMP_REGION_LOG_BUF,
596                                        __pa(addr), size);
597         /* Don't warn if this is just an older OPAL that doesn't
598          * know about that call
599          */
600         if (rc && rc != OPAL_UNSUPPORTED)
601                 pr_warn("DUMP: Failed to register kernel log buffer. "
602                         "rc = %d\n", rc);
603 }
604
605 static void opal_pdev_init(struct device_node *opal_node,
606                 const char *compatible)
607 {
608         struct device_node *np;
609
610         for_each_child_of_node(opal_node, np)
611                 if (of_device_is_compatible(np, compatible))
612                         of_platform_device_create(np, NULL, NULL);
613 }
614
615 static void opal_i2c_create_devs(void)
616 {
617         struct device_node *np;
618
619         for_each_compatible_node(np, NULL, "ibm,opal-i2c")
620                 of_platform_device_create(np, NULL, NULL);
621 }
622
623 static int kopald(void *unused)
624 {
625         __be64 events;
626
627         set_freezable();
628         do {
629                 try_to_freeze();
630                 opal_poll_events(&events);
631                 opal_handle_events(be64_to_cpu(events));
632                 msleep_interruptible(opal_heartbeat);
633         } while (!kthread_should_stop());
634
635         return 0;
636 }
637
638 static void opal_init_heartbeat(void)
639 {
640         /* Old firwmware, we assume the HVC heartbeat is sufficient */
641         if (of_property_read_u32(opal_node, "ibm,heartbeat-ms",
642                                  &opal_heartbeat) != 0)
643                 opal_heartbeat = 0;
644
645         if (opal_heartbeat)
646                 kthread_run(kopald, NULL, "kopald");
647 }
648
649 static int __init opal_init(void)
650 {
651         struct device_node *np, *consoles;
652         int rc;
653
654         opal_node = of_find_node_by_path("/ibm,opal");
655         if (!opal_node) {
656                 pr_warn("Device node not found\n");
657                 return -ENODEV;
658         }
659
660         /* Register OPAL consoles if any ports */
661         if (firmware_has_feature(FW_FEATURE_OPALv2))
662                 consoles = of_find_node_by_path("/ibm,opal/consoles");
663         else
664                 consoles = of_node_get(opal_node);
665         if (consoles) {
666                 for_each_child_of_node(consoles, np) {
667                         if (strcmp(np->name, "serial"))
668                                 continue;
669                         of_platform_device_create(np, NULL, NULL);
670                 }
671                 of_node_put(consoles);
672         }
673
674         /* Initialise OPAL messaging system */
675         opal_message_init();
676
677         /* Initialise OPAL asynchronous completion interface */
678         opal_async_comp_init();
679
680         /* Initialise OPAL sensor interface */
681         opal_sensor_init();
682
683         /* Initialise OPAL hypervisor maintainence interrupt handling */
684         opal_hmi_handler_init();
685
686         /* Create i2c platform devices */
687         opal_i2c_create_devs();
688
689         /* Setup a heatbeat thread if requested by OPAL */
690         opal_init_heartbeat();
691
692         /* Create "opal" kobject under /sys/firmware */
693         rc = opal_sysfs_init();
694         if (rc == 0) {
695                 /* Export symbol map to userspace */
696                 opal_export_symmap();
697                 /* Setup dump region interface */
698                 opal_dump_region_init();
699                 /* Setup error log interface */
700                 rc = opal_elog_init();
701                 /* Setup code update interface */
702                 opal_flash_update_init();
703                 /* Setup platform dump extract interface */
704                 opal_platform_dump_init();
705                 /* Setup system parameters interface */
706                 opal_sys_param_init();
707                 /* Setup message log interface. */
708                 opal_msglog_init();
709         }
710
711         /* Initialize platform devices: IPMI backend, PRD & flash interface */
712         opal_pdev_init(opal_node, "ibm,opal-ipmi");
713         opal_pdev_init(opal_node, "ibm,opal-flash");
714         opal_pdev_init(opal_node, "ibm,opal-prd");
715
716         return 0;
717 }
718 machine_subsys_initcall(powernv, opal_init);
719
720 void opal_shutdown(void)
721 {
722         long rc = OPAL_BUSY;
723
724         opal_event_shutdown();
725
726         /*
727          * Then sync with OPAL which ensure anything that can
728          * potentially write to our memory has completed such
729          * as an ongoing dump retrieval
730          */
731         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
732                 rc = opal_sync_host_reboot();
733                 if (rc == OPAL_BUSY)
734                         opal_poll_events(NULL);
735                 else
736                         mdelay(10);
737         }
738
739         /* Unregister memory dump region */
740         if (opal_check_token(OPAL_UNREGISTER_DUMP_REGION))
741                 opal_unregister_dump_region(OPAL_DUMP_REGION_LOG_BUF);
742 }
743
744 /* Export this so that test modules can use it */
745 EXPORT_SYMBOL_GPL(opal_invalid_call);
746 EXPORT_SYMBOL_GPL(opal_xscom_read);
747 EXPORT_SYMBOL_GPL(opal_xscom_write);
748 EXPORT_SYMBOL_GPL(opal_ipmi_send);
749 EXPORT_SYMBOL_GPL(opal_ipmi_recv);
750 EXPORT_SYMBOL_GPL(opal_flash_read);
751 EXPORT_SYMBOL_GPL(opal_flash_write);
752 EXPORT_SYMBOL_GPL(opal_flash_erase);
753 EXPORT_SYMBOL_GPL(opal_prd_msg);
754
755 /* Convert a region of vmalloc memory to an opal sg list */
756 struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr,
757                                              unsigned long vmalloc_size)
758 {
759         struct opal_sg_list *sg, *first = NULL;
760         unsigned long i = 0;
761
762         sg = kzalloc(PAGE_SIZE, GFP_KERNEL);
763         if (!sg)
764                 goto nomem;
765
766         first = sg;
767
768         while (vmalloc_size > 0) {
769                 uint64_t data = vmalloc_to_pfn(vmalloc_addr) << PAGE_SHIFT;
770                 uint64_t length = min(vmalloc_size, PAGE_SIZE);
771
772                 sg->entry[i].data = cpu_to_be64(data);
773                 sg->entry[i].length = cpu_to_be64(length);
774                 i++;
775
776                 if (i >= SG_ENTRIES_PER_NODE) {
777                         struct opal_sg_list *next;
778
779                         next = kzalloc(PAGE_SIZE, GFP_KERNEL);
780                         if (!next)
781                                 goto nomem;
782
783                         sg->length = cpu_to_be64(
784                                         i * sizeof(struct opal_sg_entry) + 16);
785                         i = 0;
786                         sg->next = cpu_to_be64(__pa(next));
787                         sg = next;
788                 }
789
790                 vmalloc_addr += length;
791                 vmalloc_size -= length;
792         }
793
794         sg->length = cpu_to_be64(i * sizeof(struct opal_sg_entry) + 16);
795
796         return first;
797
798 nomem:
799         pr_err("%s : Failed to allocate memory\n", __func__);
800         opal_free_sg_list(first);
801         return NULL;
802 }
803
804 void opal_free_sg_list(struct opal_sg_list *sg)
805 {
806         while (sg) {
807                 uint64_t next = be64_to_cpu(sg->next);
808
809                 kfree(sg);
810
811                 if (next)
812                         sg = __va(next);
813                 else
814                         sg = NULL;
815         }
816 }
817
818 int opal_error_code(int rc)
819 {
820         switch (rc) {
821         case OPAL_SUCCESS:              return 0;
822
823         case OPAL_PARAMETER:            return -EINVAL;
824         case OPAL_ASYNC_COMPLETION:     return -EINPROGRESS;
825         case OPAL_BUSY_EVENT:           return -EBUSY;
826         case OPAL_NO_MEM:               return -ENOMEM;
827         case OPAL_PERMISSION:           return -EPERM;
828
829         case OPAL_UNSUPPORTED:          return -EIO;
830         case OPAL_HARDWARE:             return -EIO;
831         case OPAL_INTERNAL_ERROR:       return -EIO;
832         default:
833                 pr_err("%s: unexpected OPAL error %d\n", __func__, rc);
834                 return -EIO;
835         }
836 }
837
838 EXPORT_SYMBOL_GPL(opal_poll_events);
839 EXPORT_SYMBOL_GPL(opal_rtc_read);
840 EXPORT_SYMBOL_GPL(opal_rtc_write);
841 EXPORT_SYMBOL_GPL(opal_tpo_read);
842 EXPORT_SYMBOL_GPL(opal_tpo_write);
843 EXPORT_SYMBOL_GPL(opal_i2c_request);