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/of_address.h>
20 #include <linux/interrupt.h>
21 #include <linux/notifier.h>
22 #include <linux/slab.h>
23 #include <linux/sched.h>
24 #include <linux/kobject.h>
25 #include <linux/delay.h>
26 #include <linux/memblock.h>
27 #include <linux/kthread.h>
28 #include <linux/freezer.h>
29 #include <linux/printk.h>
30 #include <linux/kmsg_dump.h>
31 #include <linux/console.h>
32 #include <linux/sched/debug.h>
33 
34 #include <asm/machdep.h>
35 #include <asm/opal.h>
36 #include <asm/firmware.h>
37 #include <asm/mce.h>
38 #include <asm/imc-pmu.h>
39 #include <asm/bug.h>
40 
41 #include "powernv.h"
42 
43 /* /sys/firmware/opal */
44 struct kobject *opal_kobj;
45 
46 struct opal {
47 	u64 base;
48 	u64 entry;
49 	u64 size;
50 } opal;
51 
52 struct mcheck_recoverable_range {
53 	u64 start_addr;
54 	u64 end_addr;
55 	u64 recover_addr;
56 };
57 
58 static struct mcheck_recoverable_range *mc_recoverable_range;
59 static int mc_recoverable_range_len;
60 
61 struct device_node *opal_node;
62 static DEFINE_SPINLOCK(opal_write_lock);
63 static struct atomic_notifier_head opal_msg_notifier_head[OPAL_MSG_TYPE_MAX];
64 static uint32_t opal_heartbeat;
65 static struct task_struct *kopald_tsk;
66 
opal_configure_cores(void)67 void opal_configure_cores(void)
68 {
69 	u64 reinit_flags = 0;
70 
71 	/* Do the actual re-init, This will clobber all FPRs, VRs, etc...
72 	 *
73 	 * It will preserve non volatile GPRs and HSPRG0/1. It will
74 	 * also restore HIDs and other SPRs to their original value
75 	 * but it might clobber a bunch.
76 	 */
77 #ifdef __BIG_ENDIAN__
78 	reinit_flags |= OPAL_REINIT_CPUS_HILE_BE;
79 #else
80 	reinit_flags |= OPAL_REINIT_CPUS_HILE_LE;
81 #endif
82 
83 	/*
84 	 * POWER9 always support running hash:
85 	 *  ie. Host hash  supports  hash guests
86 	 *      Host radix supports  hash/radix guests
87 	 */
88 	if (early_cpu_has_feature(CPU_FTR_ARCH_300)) {
89 		reinit_flags |= OPAL_REINIT_CPUS_MMU_HASH;
90 		if (early_radix_enabled())
91 			reinit_flags |= OPAL_REINIT_CPUS_MMU_RADIX;
92 	}
93 
94 	opal_reinit_cpus(reinit_flags);
95 
96 	/* Restore some bits */
97 	if (cur_cpu_spec->cpu_restore)
98 		cur_cpu_spec->cpu_restore();
99 }
100 
early_init_dt_scan_opal(unsigned long node,const char * uname,int depth,void * data)101 int __init early_init_dt_scan_opal(unsigned long node,
102 				   const char *uname, int depth, void *data)
103 {
104 	const void *basep, *entryp, *sizep;
105 	int basesz, entrysz, runtimesz;
106 
107 	if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
108 		return 0;
109 
110 	basep  = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
111 	entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
112 	sizep = of_get_flat_dt_prop(node, "opal-runtime-size", &runtimesz);
113 
114 	if (!basep || !entryp || !sizep)
115 		return 1;
116 
117 	opal.base = of_read_number(basep, basesz/4);
118 	opal.entry = of_read_number(entryp, entrysz/4);
119 	opal.size = of_read_number(sizep, runtimesz/4);
120 
121 	pr_debug("OPAL Base  = 0x%llx (basep=%p basesz=%d)\n",
122 		 opal.base, basep, basesz);
123 	pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%d)\n",
124 		 opal.entry, entryp, entrysz);
125 	pr_debug("OPAL Entry = 0x%llx (sizep=%p runtimesz=%d)\n",
126 		 opal.size, sizep, runtimesz);
127 
128 	if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) {
129 		powerpc_firmware_features |= FW_FEATURE_OPAL;
130 		pr_debug("OPAL detected !\n");
131 	} else {
132 		panic("OPAL != V3 detected, no longer supported.\n");
133 	}
134 
135 	return 1;
136 }
137 
early_init_dt_scan_recoverable_ranges(unsigned long node,const char * uname,int depth,void * data)138 int __init early_init_dt_scan_recoverable_ranges(unsigned long node,
139 				   const char *uname, int depth, void *data)
140 {
141 	int i, psize, size;
142 	const __be32 *prop;
143 
144 	if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
145 		return 0;
146 
147 	prop = of_get_flat_dt_prop(node, "mcheck-recoverable-ranges", &psize);
148 
149 	if (!prop)
150 		return 1;
151 
152 	pr_debug("Found machine check recoverable ranges.\n");
153 
154 	/*
155 	 * Calculate number of available entries.
156 	 *
157 	 * Each recoverable address range entry is (start address, len,
158 	 * recovery address), 2 cells each for start and recovery address,
159 	 * 1 cell for len, totalling 5 cells per entry.
160 	 */
161 	mc_recoverable_range_len = psize / (sizeof(*prop) * 5);
162 
163 	/* Sanity check */
164 	if (!mc_recoverable_range_len)
165 		return 1;
166 
167 	/* Size required to hold all the entries. */
168 	size = mc_recoverable_range_len *
169 			sizeof(struct mcheck_recoverable_range);
170 
171 	/*
172 	 * Allocate a buffer to hold the MC recoverable ranges.
173 	 */
174 	mc_recoverable_range =__va(memblock_alloc(size, __alignof__(u64)));
175 	memset(mc_recoverable_range, 0, size);
176 
177 	for (i = 0; i < mc_recoverable_range_len; i++) {
178 		mc_recoverable_range[i].start_addr =
179 					of_read_number(prop + (i * 5) + 0, 2);
180 		mc_recoverable_range[i].end_addr =
181 					mc_recoverable_range[i].start_addr +
182 					of_read_number(prop + (i * 5) + 2, 1);
183 		mc_recoverable_range[i].recover_addr =
184 					of_read_number(prop + (i * 5) + 3, 2);
185 
186 		pr_debug("Machine check recoverable range: %llx..%llx: %llx\n",
187 				mc_recoverable_range[i].start_addr,
188 				mc_recoverable_range[i].end_addr,
189 				mc_recoverable_range[i].recover_addr);
190 	}
191 	return 1;
192 }
193 
opal_register_exception_handlers(void)194 static int __init opal_register_exception_handlers(void)
195 {
196 #ifdef __BIG_ENDIAN__
197 	u64 glue;
198 
199 	if (!(powerpc_firmware_features & FW_FEATURE_OPAL))
200 		return -ENODEV;
201 
202 	/* Hookup some exception handlers except machine check. We use the
203 	 * fwnmi area at 0x7000 to provide the glue space to OPAL
204 	 */
205 	glue = 0x7000;
206 
207 	/*
208 	 * Check if we are running on newer firmware that exports
209 	 * OPAL_HANDLE_HMI token. If yes, then don't ask OPAL to patch
210 	 * the HMI interrupt and we catch it directly in Linux.
211 	 *
212 	 * For older firmware (i.e currently released POWER8 System Firmware
213 	 * as of today <= SV810_087), we fallback to old behavior and let OPAL
214 	 * patch the HMI vector and handle it inside OPAL firmware.
215 	 *
216 	 * For newer firmware (in development/yet to be released) we will
217 	 * start catching/handling HMI directly in Linux.
218 	 */
219 	if (!opal_check_token(OPAL_HANDLE_HMI)) {
220 		pr_info("Old firmware detected, OPAL handles HMIs.\n");
221 		opal_register_exception_handler(
222 				OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
223 				0, glue);
224 		glue += 128;
225 	}
226 
227 	opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
228 #endif
229 
230 	return 0;
231 }
232 machine_early_initcall(powernv, opal_register_exception_handlers);
233 
234 /*
235  * Opal message notifier based on message type. Allow subscribers to get
236  * notified for specific messgae type.
237  */
opal_message_notifier_register(enum opal_msg_type msg_type,struct notifier_block * nb)238 int opal_message_notifier_register(enum opal_msg_type msg_type,
239 					struct notifier_block *nb)
240 {
241 	if (!nb || msg_type >= OPAL_MSG_TYPE_MAX) {
242 		pr_warn("%s: Invalid arguments, msg_type:%d\n",
243 			__func__, msg_type);
244 		return -EINVAL;
245 	}
246 
247 	return atomic_notifier_chain_register(
248 				&opal_msg_notifier_head[msg_type], nb);
249 }
250 EXPORT_SYMBOL_GPL(opal_message_notifier_register);
251 
opal_message_notifier_unregister(enum opal_msg_type msg_type,struct notifier_block * nb)252 int opal_message_notifier_unregister(enum opal_msg_type msg_type,
253 				     struct notifier_block *nb)
254 {
255 	return atomic_notifier_chain_unregister(
256 			&opal_msg_notifier_head[msg_type], nb);
257 }
258 EXPORT_SYMBOL_GPL(opal_message_notifier_unregister);
259 
opal_message_do_notify(uint32_t msg_type,void * msg)260 static void opal_message_do_notify(uint32_t msg_type, void *msg)
261 {
262 	/* notify subscribers */
263 	atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
264 					msg_type, msg);
265 }
266 
opal_handle_message(void)267 static void opal_handle_message(void)
268 {
269 	s64 ret;
270 	/*
271 	 * TODO: pre-allocate a message buffer depending on opal-msg-size
272 	 * value in /proc/device-tree.
273 	 */
274 	static struct opal_msg msg;
275 	u32 type;
276 
277 	ret = opal_get_msg(__pa(&msg), sizeof(msg));
278 	/* No opal message pending. */
279 	if (ret == OPAL_RESOURCE)
280 		return;
281 
282 	/* check for errors. */
283 	if (ret) {
284 		pr_warn("%s: Failed to retrieve opal message, err=%lld\n",
285 			__func__, ret);
286 		return;
287 	}
288 
289 	type = be32_to_cpu(msg.msg_type);
290 
291 	/* Sanity check */
292 	if (type >= OPAL_MSG_TYPE_MAX) {
293 		pr_warn_once("%s: Unknown message type: %u\n", __func__, type);
294 		return;
295 	}
296 	opal_message_do_notify(type, (void *)&msg);
297 }
298 
opal_message_notify(int irq,void * data)299 static irqreturn_t opal_message_notify(int irq, void *data)
300 {
301 	opal_handle_message();
302 	return IRQ_HANDLED;
303 }
304 
opal_message_init(void)305 static int __init opal_message_init(void)
306 {
307 	int ret, i, irq;
308 
309 	for (i = 0; i < OPAL_MSG_TYPE_MAX; i++)
310 		ATOMIC_INIT_NOTIFIER_HEAD(&opal_msg_notifier_head[i]);
311 
312 	irq = opal_event_request(ilog2(OPAL_EVENT_MSG_PENDING));
313 	if (!irq) {
314 		pr_err("%s: Can't register OPAL event irq (%d)\n",
315 		       __func__, irq);
316 		return irq;
317 	}
318 
319 	ret = request_irq(irq, opal_message_notify,
320 			IRQ_TYPE_LEVEL_HIGH, "opal-msg", NULL);
321 	if (ret) {
322 		pr_err("%s: Can't request OPAL event irq (%d)\n",
323 		       __func__, ret);
324 		return ret;
325 	}
326 
327 	return 0;
328 }
329 
opal_get_chars(uint32_t vtermno,char * buf,int count)330 int opal_get_chars(uint32_t vtermno, char *buf, int count)
331 {
332 	s64 rc;
333 	__be64 evt, len;
334 
335 	if (!opal.entry)
336 		return -ENODEV;
337 	opal_poll_events(&evt);
338 	if ((be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_INPUT) == 0)
339 		return 0;
340 	len = cpu_to_be64(count);
341 	rc = opal_console_read(vtermno, &len, buf);
342 	if (rc == OPAL_SUCCESS)
343 		return be64_to_cpu(len);
344 	return 0;
345 }
346 
__opal_put_chars(uint32_t vtermno,const char * data,int total_len,bool atomic)347 static int __opal_put_chars(uint32_t vtermno, const char *data, int total_len, bool atomic)
348 {
349 	unsigned long flags = 0 /* shut up gcc */;
350 	int written;
351 	__be64 olen;
352 	s64 rc;
353 
354 	if (!opal.entry)
355 		return -ENODEV;
356 
357 	if (atomic)
358 		spin_lock_irqsave(&opal_write_lock, flags);
359 	rc = opal_console_write_buffer_space(vtermno, &olen);
360 	if (rc || be64_to_cpu(olen) < total_len) {
361 		/* Closed -> drop characters */
362 		if (rc)
363 			written = total_len;
364 		else
365 			written = -EAGAIN;
366 		goto out;
367 	}
368 
369 	/* Should not get a partial write here because space is available. */
370 	olen = cpu_to_be64(total_len);
371 	rc = opal_console_write(vtermno, &olen, data);
372 	if (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
373 		if (rc == OPAL_BUSY_EVENT)
374 			opal_poll_events(NULL);
375 		written = -EAGAIN;
376 		goto out;
377 	}
378 
379 	/* Closed or other error drop */
380 	if (rc != OPAL_SUCCESS) {
381 		written = opal_error_code(rc);
382 		goto out;
383 	}
384 
385 	written = be64_to_cpu(olen);
386 	if (written < total_len) {
387 		if (atomic) {
388 			/* Should not happen */
389 			pr_warn("atomic console write returned partial "
390 				"len=%d written=%d\n", total_len, written);
391 		}
392 		if (!written)
393 			written = -EAGAIN;
394 	}
395 
396 out:
397 	if (atomic)
398 		spin_unlock_irqrestore(&opal_write_lock, flags);
399 
400 	return written;
401 }
402 
opal_put_chars(uint32_t vtermno,const char * data,int total_len)403 int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
404 {
405 	return __opal_put_chars(vtermno, data, total_len, false);
406 }
407 
408 /*
409  * opal_put_chars_atomic will not perform partial-writes. Data will be
410  * atomically written to the terminal or not at all. This is not strictly
411  * true at the moment because console space can race with OPAL's console
412  * writes.
413  */
opal_put_chars_atomic(uint32_t vtermno,const char * data,int total_len)414 int opal_put_chars_atomic(uint32_t vtermno, const char *data, int total_len)
415 {
416 	return __opal_put_chars(vtermno, data, total_len, true);
417 }
418 
__opal_flush_console(uint32_t vtermno)419 static s64 __opal_flush_console(uint32_t vtermno)
420 {
421 	s64 rc;
422 
423 	if (!opal_check_token(OPAL_CONSOLE_FLUSH)) {
424 		__be64 evt;
425 
426 		/*
427 		 * If OPAL_CONSOLE_FLUSH is not implemented in the firmware,
428 		 * the console can still be flushed by calling the polling
429 		 * function while it has OPAL_EVENT_CONSOLE_OUTPUT events.
430 		 */
431 		WARN_ONCE(1, "opal: OPAL_CONSOLE_FLUSH missing.\n");
432 
433 		opal_poll_events(&evt);
434 		if (!(be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT))
435 			return OPAL_SUCCESS;
436 		return OPAL_BUSY;
437 
438 	} else {
439 		rc = opal_console_flush(vtermno);
440 		if (rc == OPAL_BUSY_EVENT) {
441 			opal_poll_events(NULL);
442 			rc = OPAL_BUSY;
443 		}
444 		return rc;
445 	}
446 
447 }
448 
449 /*
450  * opal_flush_console spins until the console is flushed
451  */
opal_flush_console(uint32_t vtermno)452 int opal_flush_console(uint32_t vtermno)
453 {
454 	for (;;) {
455 		s64 rc = __opal_flush_console(vtermno);
456 
457 		if (rc == OPAL_BUSY || rc == OPAL_PARTIAL) {
458 			mdelay(1);
459 			continue;
460 		}
461 
462 		return opal_error_code(rc);
463 	}
464 }
465 
466 /*
467  * opal_flush_chars is an hvc interface that sleeps until the console is
468  * flushed if wait, otherwise it will return -EBUSY if the console has data,
469  * -EAGAIN if it has data and some of it was flushed.
470  */
opal_flush_chars(uint32_t vtermno,bool wait)471 int opal_flush_chars(uint32_t vtermno, bool wait)
472 {
473 	for (;;) {
474 		s64 rc = __opal_flush_console(vtermno);
475 
476 		if (rc == OPAL_BUSY || rc == OPAL_PARTIAL) {
477 			if (wait) {
478 				msleep(OPAL_BUSY_DELAY_MS);
479 				continue;
480 			}
481 			if (rc == OPAL_PARTIAL)
482 				return -EAGAIN;
483 		}
484 
485 		return opal_error_code(rc);
486 	}
487 }
488 
opal_recover_mce(struct pt_regs * regs,struct machine_check_event * evt)489 static int opal_recover_mce(struct pt_regs *regs,
490 					struct machine_check_event *evt)
491 {
492 	int recovered = 0;
493 
494 	if (!(regs->msr & MSR_RI)) {
495 		/* If MSR_RI isn't set, we cannot recover */
496 		pr_err("Machine check interrupt unrecoverable: MSR(RI=0)\n");
497 		recovered = 0;
498 	} else if (evt->disposition == MCE_DISPOSITION_RECOVERED) {
499 		/* Platform corrected itself */
500 		recovered = 1;
501 	} else if (evt->severity == MCE_SEV_FATAL) {
502 		/* Fatal machine check */
503 		pr_err("Machine check interrupt is fatal\n");
504 		recovered = 0;
505 	}
506 
507 	if (!recovered && evt->severity == MCE_SEV_ERROR_SYNC) {
508 		/*
509 		 * Try to kill processes if we get a synchronous machine check
510 		 * (e.g., one caused by execution of this instruction). This
511 		 * will devolve into a panic if we try to kill init or are in
512 		 * an interrupt etc.
513 		 *
514 		 * TODO: Queue up this address for hwpoisioning later.
515 		 * TODO: This is not quite right for d-side machine
516 		 *       checks ->nip is not necessarily the important
517 		 *       address.
518 		 */
519 		if ((user_mode(regs))) {
520 			_exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
521 			recovered = 1;
522 		} else if (die_will_crash()) {
523 			/*
524 			 * die() would kill the kernel, so better to go via
525 			 * the platform reboot code that will log the
526 			 * machine check.
527 			 */
528 			recovered = 0;
529 		} else {
530 			die("Machine check", regs, SIGBUS);
531 			recovered = 1;
532 		}
533 	}
534 
535 	return recovered;
536 }
537 
pnv_platform_error_reboot(struct pt_regs * regs,const char * msg)538 void pnv_platform_error_reboot(struct pt_regs *regs, const char *msg)
539 {
540 	panic_flush_kmsg_start();
541 
542 	pr_emerg("Hardware platform error: %s\n", msg);
543 	if (regs)
544 		show_regs(regs);
545 	smp_send_stop();
546 
547 	panic_flush_kmsg_end();
548 
549 	/*
550 	 * Don't bother to shut things down because this will
551 	 * xstop the system.
552 	 */
553 	if (opal_cec_reboot2(OPAL_REBOOT_PLATFORM_ERROR, msg)
554 						== OPAL_UNSUPPORTED) {
555 		pr_emerg("Reboot type %d not supported for %s\n",
556 				OPAL_REBOOT_PLATFORM_ERROR, msg);
557 	}
558 
559 	/*
560 	 * We reached here. There can be three possibilities:
561 	 * 1. We are running on a firmware level that do not support
562 	 *    opal_cec_reboot2()
563 	 * 2. We are running on a firmware level that do not support
564 	 *    OPAL_REBOOT_PLATFORM_ERROR reboot type.
565 	 * 3. We are running on FSP based system that does not need
566 	 *    opal to trigger checkstop explicitly for error analysis.
567 	 *    The FSP PRD component would have already got notified
568 	 *    about this error through other channels.
569 	 * 4. We are running on a newer skiboot that by default does
570 	 *    not cause a checkstop, drops us back to the kernel to
571 	 *    extract context and state at the time of the error.
572 	 */
573 
574 	panic(msg);
575 }
576 
opal_machine_check(struct pt_regs * regs)577 int opal_machine_check(struct pt_regs *regs)
578 {
579 	struct machine_check_event evt;
580 
581 	if (!get_mce_event(&evt, MCE_EVENT_RELEASE))
582 		return 0;
583 
584 	/* Print things out */
585 	if (evt.version != MCE_V1) {
586 		pr_err("Machine Check Exception, Unknown event version %d !\n",
587 		       evt.version);
588 		return 0;
589 	}
590 	machine_check_print_event_info(&evt, user_mode(regs));
591 
592 	if (opal_recover_mce(regs, &evt))
593 		return 1;
594 
595 	pnv_platform_error_reboot(regs, "Unrecoverable Machine Check exception");
596 }
597 
598 /* Early hmi handler called in real mode. */
opal_hmi_exception_early(struct pt_regs * regs)599 int opal_hmi_exception_early(struct pt_regs *regs)
600 {
601 	s64 rc;
602 
603 	/*
604 	 * call opal hmi handler. Pass paca address as token.
605 	 * The return value OPAL_SUCCESS is an indication that there is
606 	 * an HMI event generated waiting to pull by Linux.
607 	 */
608 	rc = opal_handle_hmi();
609 	if (rc == OPAL_SUCCESS) {
610 		local_paca->hmi_event_available = 1;
611 		return 1;
612 	}
613 	return 0;
614 }
615 
616 /* HMI exception handler called in virtual mode during check_irq_replay. */
opal_handle_hmi_exception(struct pt_regs * regs)617 int opal_handle_hmi_exception(struct pt_regs *regs)
618 {
619 	/*
620 	 * Check if HMI event is available.
621 	 * if Yes, then wake kopald to process them.
622 	 */
623 	if (!local_paca->hmi_event_available)
624 		return 0;
625 
626 	local_paca->hmi_event_available = 0;
627 	opal_wake_poller();
628 
629 	return 1;
630 }
631 
find_recovery_address(uint64_t nip)632 static uint64_t find_recovery_address(uint64_t nip)
633 {
634 	int i;
635 
636 	for (i = 0; i < mc_recoverable_range_len; i++)
637 		if ((nip >= mc_recoverable_range[i].start_addr) &&
638 		    (nip < mc_recoverable_range[i].end_addr))
639 		    return mc_recoverable_range[i].recover_addr;
640 	return 0;
641 }
642 
opal_mce_check_early_recovery(struct pt_regs * regs)643 bool opal_mce_check_early_recovery(struct pt_regs *regs)
644 {
645 	uint64_t recover_addr = 0;
646 
647 	if (!opal.base || !opal.size)
648 		goto out;
649 
650 	if ((regs->nip >= opal.base) &&
651 			(regs->nip < (opal.base + opal.size)))
652 		recover_addr = find_recovery_address(regs->nip);
653 
654 	/*
655 	 * Setup regs->nip to rfi into fixup address.
656 	 */
657 	if (recover_addr)
658 		regs->nip = recover_addr;
659 
660 out:
661 	return !!recover_addr;
662 }
663 
opal_sysfs_init(void)664 static int opal_sysfs_init(void)
665 {
666 	opal_kobj = kobject_create_and_add("opal", firmware_kobj);
667 	if (!opal_kobj) {
668 		pr_warn("kobject_create_and_add opal failed\n");
669 		return -ENOMEM;
670 	}
671 
672 	return 0;
673 }
674 
symbol_map_read(struct file * fp,struct kobject * kobj,struct bin_attribute * bin_attr,char * buf,loff_t off,size_t count)675 static ssize_t symbol_map_read(struct file *fp, struct kobject *kobj,
676 			       struct bin_attribute *bin_attr,
677 			       char *buf, loff_t off, size_t count)
678 {
679 	return memory_read_from_buffer(buf, count, &off, bin_attr->private,
680 				       bin_attr->size);
681 }
682 
683 static BIN_ATTR_RO(symbol_map, 0);
684 
opal_export_symmap(void)685 static void opal_export_symmap(void)
686 {
687 	const __be64 *syms;
688 	unsigned int size;
689 	struct device_node *fw;
690 	int rc;
691 
692 	fw = of_find_node_by_path("/ibm,opal/firmware");
693 	if (!fw)
694 		return;
695 	syms = of_get_property(fw, "symbol-map", &size);
696 	if (!syms || size != 2 * sizeof(__be64))
697 		return;
698 
699 	/* Setup attributes */
700 	bin_attr_symbol_map.private = __va(be64_to_cpu(syms[0]));
701 	bin_attr_symbol_map.size = be64_to_cpu(syms[1]);
702 
703 	rc = sysfs_create_bin_file(opal_kobj, &bin_attr_symbol_map);
704 	if (rc)
705 		pr_warn("Error %d creating OPAL symbols file\n", rc);
706 }
707 
export_attr_read(struct file * fp,struct kobject * kobj,struct bin_attribute * bin_attr,char * buf,loff_t off,size_t count)708 static ssize_t export_attr_read(struct file *fp, struct kobject *kobj,
709 				struct bin_attribute *bin_attr, char *buf,
710 				loff_t off, size_t count)
711 {
712 	return memory_read_from_buffer(buf, count, &off, bin_attr->private,
713 				       bin_attr->size);
714 }
715 
716 /*
717  * opal_export_attrs: creates a sysfs node for each property listed in
718  * the device-tree under /ibm,opal/firmware/exports/
719  * All new sysfs nodes are created under /opal/exports/.
720  * This allows for reserved memory regions (e.g. HDAT) to be read.
721  * The new sysfs nodes are only readable by root.
722  */
opal_export_attrs(void)723 static void opal_export_attrs(void)
724 {
725 	struct bin_attribute *attr;
726 	struct device_node *np;
727 	struct property *prop;
728 	struct kobject *kobj;
729 	u64 vals[2];
730 	int rc;
731 
732 	np = of_find_node_by_path("/ibm,opal/firmware/exports");
733 	if (!np)
734 		return;
735 
736 	/* Create new 'exports' directory - /sys/firmware/opal/exports */
737 	kobj = kobject_create_and_add("exports", opal_kobj);
738 	if (!kobj) {
739 		pr_warn("kobject_create_and_add() of exports failed\n");
740 		return;
741 	}
742 
743 	for_each_property_of_node(np, prop) {
744 		if (!strcmp(prop->name, "name") || !strcmp(prop->name, "phandle"))
745 			continue;
746 
747 		if (of_property_read_u64_array(np, prop->name, &vals[0], 2))
748 			continue;
749 
750 		attr = kzalloc(sizeof(*attr), GFP_KERNEL);
751 
752 		if (attr == NULL) {
753 			pr_warn("Failed kmalloc for bin_attribute!");
754 			continue;
755 		}
756 
757 		sysfs_bin_attr_init(attr);
758 		attr->attr.name = kstrdup(prop->name, GFP_KERNEL);
759 		attr->attr.mode = 0400;
760 		attr->read = export_attr_read;
761 		attr->private = __va(vals[0]);
762 		attr->size = vals[1];
763 
764 		if (attr->attr.name == NULL) {
765 			pr_warn("Failed kstrdup for bin_attribute attr.name");
766 			kfree(attr);
767 			continue;
768 		}
769 
770 		rc = sysfs_create_bin_file(kobj, attr);
771 		if (rc) {
772 			pr_warn("Error %d creating OPAL sysfs exports/%s file\n",
773 				 rc, prop->name);
774 			kfree(attr->attr.name);
775 			kfree(attr);
776 		}
777 	}
778 
779 	of_node_put(np);
780 }
781 
opal_dump_region_init(void)782 static void __init opal_dump_region_init(void)
783 {
784 	void *addr;
785 	uint64_t size;
786 	int rc;
787 
788 	if (!opal_check_token(OPAL_REGISTER_DUMP_REGION))
789 		return;
790 
791 	/* Register kernel log buffer */
792 	addr = log_buf_addr_get();
793 	if (addr == NULL)
794 		return;
795 
796 	size = log_buf_len_get();
797 	if (size == 0)
798 		return;
799 
800 	rc = opal_register_dump_region(OPAL_DUMP_REGION_LOG_BUF,
801 				       __pa(addr), size);
802 	/* Don't warn if this is just an older OPAL that doesn't
803 	 * know about that call
804 	 */
805 	if (rc && rc != OPAL_UNSUPPORTED)
806 		pr_warn("DUMP: Failed to register kernel log buffer. "
807 			"rc = %d\n", rc);
808 }
809 
opal_pdev_init(const char * compatible)810 static void opal_pdev_init(const char *compatible)
811 {
812 	struct device_node *np;
813 
814 	for_each_compatible_node(np, NULL, compatible)
815 		of_platform_device_create(np, NULL, NULL);
816 }
817 
opal_imc_init_dev(void)818 static void __init opal_imc_init_dev(void)
819 {
820 	struct device_node *np;
821 
822 	np = of_find_compatible_node(NULL, NULL, IMC_DTB_COMPAT);
823 	if (np)
824 		of_platform_device_create(np, NULL, NULL);
825 }
826 
kopald(void * unused)827 static int kopald(void *unused)
828 {
829 	unsigned long timeout = msecs_to_jiffies(opal_heartbeat) + 1;
830 
831 	set_freezable();
832 	do {
833 		try_to_freeze();
834 
835 		opal_handle_events();
836 
837 		set_current_state(TASK_INTERRUPTIBLE);
838 		if (opal_have_pending_events())
839 			__set_current_state(TASK_RUNNING);
840 		else
841 			schedule_timeout(timeout);
842 
843 	} while (!kthread_should_stop());
844 
845 	return 0;
846 }
847 
opal_wake_poller(void)848 void opal_wake_poller(void)
849 {
850 	if (kopald_tsk)
851 		wake_up_process(kopald_tsk);
852 }
853 
opal_init_heartbeat(void)854 static void opal_init_heartbeat(void)
855 {
856 	/* Old firwmware, we assume the HVC heartbeat is sufficient */
857 	if (of_property_read_u32(opal_node, "ibm,heartbeat-ms",
858 				 &opal_heartbeat) != 0)
859 		opal_heartbeat = 0;
860 
861 	if (opal_heartbeat)
862 		kopald_tsk = kthread_run(kopald, NULL, "kopald");
863 }
864 
opal_init(void)865 static int __init opal_init(void)
866 {
867 	struct device_node *np, *consoles, *leds;
868 	int rc;
869 
870 	opal_node = of_find_node_by_path("/ibm,opal");
871 	if (!opal_node) {
872 		pr_warn("Device node not found\n");
873 		return -ENODEV;
874 	}
875 
876 	/* Register OPAL consoles if any ports */
877 	consoles = of_find_node_by_path("/ibm,opal/consoles");
878 	if (consoles) {
879 		for_each_child_of_node(consoles, np) {
880 			if (strcmp(np->name, "serial"))
881 				continue;
882 			of_platform_device_create(np, NULL, NULL);
883 		}
884 		of_node_put(consoles);
885 	}
886 
887 	/* Initialise OPAL messaging system */
888 	opal_message_init();
889 
890 	/* Initialise OPAL asynchronous completion interface */
891 	opal_async_comp_init();
892 
893 	/* Initialise OPAL sensor interface */
894 	opal_sensor_init();
895 
896 	/* Initialise OPAL hypervisor maintainence interrupt handling */
897 	opal_hmi_handler_init();
898 
899 	/* Create i2c platform devices */
900 	opal_pdev_init("ibm,opal-i2c");
901 
902 	/* Handle non-volatile memory devices */
903 	opal_pdev_init("pmem-region");
904 
905 	/* Setup a heatbeat thread if requested by OPAL */
906 	opal_init_heartbeat();
907 
908 	/* Detect In-Memory Collection counters and create devices*/
909 	opal_imc_init_dev();
910 
911 	/* Create leds platform devices */
912 	leds = of_find_node_by_path("/ibm,opal/leds");
913 	if (leds) {
914 		of_platform_device_create(leds, "opal_leds", NULL);
915 		of_node_put(leds);
916 	}
917 
918 	/* Initialise OPAL message log interface */
919 	opal_msglog_init();
920 
921 	/* Create "opal" kobject under /sys/firmware */
922 	rc = opal_sysfs_init();
923 	if (rc == 0) {
924 		/* Export symbol map to userspace */
925 		opal_export_symmap();
926 		/* Setup dump region interface */
927 		opal_dump_region_init();
928 		/* Setup error log interface */
929 		rc = opal_elog_init();
930 		/* Setup code update interface */
931 		opal_flash_update_init();
932 		/* Setup platform dump extract interface */
933 		opal_platform_dump_init();
934 		/* Setup system parameters interface */
935 		opal_sys_param_init();
936 		/* Setup message log sysfs interface. */
937 		opal_msglog_sysfs_init();
938 	}
939 
940 	/* Export all properties */
941 	opal_export_attrs();
942 
943 	/* Initialize platform devices: IPMI backend, PRD & flash interface */
944 	opal_pdev_init("ibm,opal-ipmi");
945 	opal_pdev_init("ibm,opal-flash");
946 	opal_pdev_init("ibm,opal-prd");
947 
948 	/* Initialise platform device: oppanel interface */
949 	opal_pdev_init("ibm,opal-oppanel");
950 
951 	/* Initialise OPAL kmsg dumper for flushing console on panic */
952 	opal_kmsg_init();
953 
954 	/* Initialise OPAL powercap interface */
955 	opal_powercap_init();
956 
957 	/* Initialise OPAL Power-Shifting-Ratio interface */
958 	opal_psr_init();
959 
960 	/* Initialise OPAL sensor groups */
961 	opal_sensor_groups_init();
962 
963 	return 0;
964 }
965 machine_subsys_initcall(powernv, opal_init);
966 
opal_shutdown(void)967 void opal_shutdown(void)
968 {
969 	long rc = OPAL_BUSY;
970 
971 	opal_event_shutdown();
972 
973 	/*
974 	 * Then sync with OPAL which ensure anything that can
975 	 * potentially write to our memory has completed such
976 	 * as an ongoing dump retrieval
977 	 */
978 	while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
979 		rc = opal_sync_host_reboot();
980 		if (rc == OPAL_BUSY)
981 			opal_poll_events(NULL);
982 		else
983 			mdelay(10);
984 	}
985 
986 	/* Unregister memory dump region */
987 	if (opal_check_token(OPAL_UNREGISTER_DUMP_REGION))
988 		opal_unregister_dump_region(OPAL_DUMP_REGION_LOG_BUF);
989 }
990 
991 /* Export this so that test modules can use it */
992 EXPORT_SYMBOL_GPL(opal_invalid_call);
993 EXPORT_SYMBOL_GPL(opal_xscom_read);
994 EXPORT_SYMBOL_GPL(opal_xscom_write);
995 EXPORT_SYMBOL_GPL(opal_ipmi_send);
996 EXPORT_SYMBOL_GPL(opal_ipmi_recv);
997 EXPORT_SYMBOL_GPL(opal_flash_read);
998 EXPORT_SYMBOL_GPL(opal_flash_write);
999 EXPORT_SYMBOL_GPL(opal_flash_erase);
1000 EXPORT_SYMBOL_GPL(opal_prd_msg);
1001 EXPORT_SYMBOL_GPL(opal_check_token);
1002 
1003 /* Convert a region of vmalloc memory to an opal sg list */
opal_vmalloc_to_sg_list(void * vmalloc_addr,unsigned long vmalloc_size)1004 struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr,
1005 					     unsigned long vmalloc_size)
1006 {
1007 	struct opal_sg_list *sg, *first = NULL;
1008 	unsigned long i = 0;
1009 
1010 	sg = kzalloc(PAGE_SIZE, GFP_KERNEL);
1011 	if (!sg)
1012 		goto nomem;
1013 
1014 	first = sg;
1015 
1016 	while (vmalloc_size > 0) {
1017 		uint64_t data = vmalloc_to_pfn(vmalloc_addr) << PAGE_SHIFT;
1018 		uint64_t length = min(vmalloc_size, PAGE_SIZE);
1019 
1020 		sg->entry[i].data = cpu_to_be64(data);
1021 		sg->entry[i].length = cpu_to_be64(length);
1022 		i++;
1023 
1024 		if (i >= SG_ENTRIES_PER_NODE) {
1025 			struct opal_sg_list *next;
1026 
1027 			next = kzalloc(PAGE_SIZE, GFP_KERNEL);
1028 			if (!next)
1029 				goto nomem;
1030 
1031 			sg->length = cpu_to_be64(
1032 					i * sizeof(struct opal_sg_entry) + 16);
1033 			i = 0;
1034 			sg->next = cpu_to_be64(__pa(next));
1035 			sg = next;
1036 		}
1037 
1038 		vmalloc_addr += length;
1039 		vmalloc_size -= length;
1040 	}
1041 
1042 	sg->length = cpu_to_be64(i * sizeof(struct opal_sg_entry) + 16);
1043 
1044 	return first;
1045 
1046 nomem:
1047 	pr_err("%s : Failed to allocate memory\n", __func__);
1048 	opal_free_sg_list(first);
1049 	return NULL;
1050 }
1051 
opal_free_sg_list(struct opal_sg_list * sg)1052 void opal_free_sg_list(struct opal_sg_list *sg)
1053 {
1054 	while (sg) {
1055 		uint64_t next = be64_to_cpu(sg->next);
1056 
1057 		kfree(sg);
1058 
1059 		if (next)
1060 			sg = __va(next);
1061 		else
1062 			sg = NULL;
1063 	}
1064 }
1065 
opal_error_code(int rc)1066 int opal_error_code(int rc)
1067 {
1068 	switch (rc) {
1069 	case OPAL_SUCCESS:		return 0;
1070 
1071 	case OPAL_PARAMETER:		return -EINVAL;
1072 	case OPAL_ASYNC_COMPLETION:	return -EINPROGRESS;
1073 	case OPAL_BUSY:
1074 	case OPAL_BUSY_EVENT:		return -EBUSY;
1075 	case OPAL_NO_MEM:		return -ENOMEM;
1076 	case OPAL_PERMISSION:		return -EPERM;
1077 
1078 	case OPAL_UNSUPPORTED:		return -EIO;
1079 	case OPAL_HARDWARE:		return -EIO;
1080 	case OPAL_INTERNAL_ERROR:	return -EIO;
1081 	case OPAL_TIMEOUT:		return -ETIMEDOUT;
1082 	default:
1083 		pr_err("%s: unexpected OPAL error %d\n", __func__, rc);
1084 		return -EIO;
1085 	}
1086 }
1087 
powernv_set_nmmu_ptcr(unsigned long ptcr)1088 void powernv_set_nmmu_ptcr(unsigned long ptcr)
1089 {
1090 	int rc;
1091 
1092 	if (firmware_has_feature(FW_FEATURE_OPAL)) {
1093 		rc = opal_nmmu_set_ptcr(-1UL, ptcr);
1094 		if (rc != OPAL_SUCCESS && rc != OPAL_UNSUPPORTED)
1095 			pr_warn("%s: Unable to set nest mmu ptcr\n", __func__);
1096 	}
1097 }
1098 
1099 EXPORT_SYMBOL_GPL(opal_poll_events);
1100 EXPORT_SYMBOL_GPL(opal_rtc_read);
1101 EXPORT_SYMBOL_GPL(opal_rtc_write);
1102 EXPORT_SYMBOL_GPL(opal_tpo_read);
1103 EXPORT_SYMBOL_GPL(opal_tpo_write);
1104 EXPORT_SYMBOL_GPL(opal_i2c_request);
1105 /* Export these symbols for PowerNV LED class driver */
1106 EXPORT_SYMBOL_GPL(opal_leds_get_ind);
1107 EXPORT_SYMBOL_GPL(opal_leds_set_ind);
1108 /* Export this symbol for PowerNV Operator Panel class driver */
1109 EXPORT_SYMBOL_GPL(opal_write_oppanel_async);
1110 /* Export this for KVM */
1111 EXPORT_SYMBOL_GPL(opal_int_set_mfrr);
1112 EXPORT_SYMBOL_GPL(opal_int_eoi);
1113 EXPORT_SYMBOL_GPL(opal_error_code);
1114 /* Export the below symbol for NX compression */
1115 EXPORT_SYMBOL(opal_nx_coproc_init);
1116