1 // SPDX-License-Identifier: GPL-2.0-or-later
4  * Procedures for interfacing to the RTAS on CHRP machines.
29 #include <asm/rtas.h>
46 /* This is here deliberately so it's only used in this file */
49 struct rtas_t rtas = {  variable
52 EXPORT_SYMBOL(rtas);
63  * If non-NULL, this gets called when the kernel terminates.
69 /* RTAS use home made raw locking instead of spin_lock_irqsave
80 	arch_spin_lock(&rtas.lock);  in lock_rtas()
86 	arch_spin_unlock(&rtas.lock);  in unlock_rtas()
93  * are designed only for very early low-level debugging, which
94  * is why the token is hard-coded to 10.
100 	if (!rtas.base)  in call_rtas_display_status()
104 	rtas_call_unlocked(&rtas.args, 10, 1, 1, NULL, c);  in call_rtas_display_status()
114 		while (width-- > 0)  in call_rtas_display_status_delay()
125 		if (width--) {  in call_rtas_display_status_delay()
141  * hardcode rtas.base/entry etc.
150 	if (!rtas.base)  in udbg_rtascon_putc()
169 	if (!rtas.base)  in udbg_rtascon_getc_poll()
170 		return -1;  in udbg_rtascon_getc_poll()
173 		return -1;  in udbg_rtascon_getc_poll()
182 	while ((c = udbg_rtascon_getc_poll()) == -1)  in udbg_rtascon_getc()
210 	if (!rtas.base)  in rtas_progress()
215 		if ((root = of_find_node_by_path("/rtas"))) {  in rtas_progress()
217 					"ibm,display-line-length", NULL)))  in rtas_progress()
220 					"ibm,form-feed", NULL)))  in rtas_progress()
223 					"ibm,display-number-of-lines", NULL)))  in rtas_progress()
226 					"ibm,display-truncation-length", NULL);  in rtas_progress()
229 		display_character = rtas_token("display-character");  in rtas_progress()
230 		set_indicator = rtas_token("set-indicator");  in rtas_progress()
278 				if (current_line > display_lines-1)  in rtas_progress()
279 					current_line = display_lines-1;  in rtas_progress()
284 			/* RTAS wants CR-LF, not just LF */  in rtas_progress()
290 				/* CR might be used to re-draw a line, so we'll  in rtas_progress()
301 			width--;  in rtas_progress()
315 EXPORT_SYMBOL(rtas_progress);		/* needed by rtas_flash module */
320 	if (rtas.dev == NULL)  in rtas_token()
322 	tokp = of_get_property(rtas.dev, service, NULL);  in rtas_token()
335  * Return the firmware-specified size of the error log buffer
336  *  for all rtas calls that require an error buffer argument.
337  *  This includes 'check-exception' and 'rtas-last-error'.
345 	rtas_error_log_max = rtas_token ("rtas-error-log-max");  in rtas_get_error_log_max()
348 		printk (KERN_WARNING "RTAS: bad log buffer size %d\n",  in rtas_get_error_log_max()
361  *  most recent failed call to rtas.  Because the error text
362  *  might go stale if there are any other intervening rtas calls,
364  *  the error (i.e. with rtas.lock still held from the previous call).
372 	if (rtas_last_error_token == -1)  in __fetch_rtas_last_error()
384 	save_args = rtas.args;  in __fetch_rtas_last_error()
385 	rtas.args = err_args;  in __fetch_rtas_last_error()
387 	enter_rtas(__pa(&rtas.args));  in __fetch_rtas_last_error()
389 	err_args = rtas.args;  in __fetch_rtas_last_error()
390 	rtas.args = save_args;  in __fetch_rtas_last_error()
422 	args->token = cpu_to_be32(token);  in va_rtas_call_unlocked()
423 	args->nargs = cpu_to_be32(nargs);  in va_rtas_call_unlocked()
424 	args->nret  = cpu_to_be32(nret);  in va_rtas_call_unlocked()
425 	args->rets  = &(args->args[nargs]);  in va_rtas_call_unlocked()
428 		args->args[i] = cpu_to_be32(va_arg(list, __u32));  in va_rtas_call_unlocked()
431 		args->rets[i] = 0;  in va_rtas_call_unlocked()
454 	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)  in rtas_call()
455 		return -1;  in rtas_call()
459 	/* We use the global rtas args buffer */  in rtas_call()
460 	rtas_args = &rtas.args;  in rtas_call()
466 	/* A -1 return code indicates that the last command couldn't  in rtas_call()
468 	if (be32_to_cpu(rtas_args->rets[0]) == -1)  in rtas_call()
472 		for (i = 0; i < nret-1; ++i)  in rtas_call()
473 			outputs[i] = be32_to_cpu(rtas_args->rets[i+1]);  in rtas_call()
474 	ret = (nret > 0)? be32_to_cpu(rtas_args->rets[0]): 0;  in rtas_call()
487 /* For RTAS_BUSY (-2), delay for 1 millisecond.  For an extended busy status
499 		order = status - RTAS_EXTENDED_DELAY_MIN;  in rtas_busy_delay_time()
500 		for (ms = 1; order > 0; order--)  in rtas_busy_delay_time()
508 /* For an RTAS busy status code, perform the hinted delay. */
527 		case -1: 		/* Hardware Error */  in rtas_error_rc()
528 			rc = -EIO;  in rtas_error_rc()
530 		case -3:		/* Bad indicator/domain/etc */  in rtas_error_rc()
531 			rc = -EINVAL;  in rtas_error_rc()
533 		case -9000:		/* Isolation error */  in rtas_error_rc()
534 			rc = -EFAULT;  in rtas_error_rc()
536 		case -9001:		/* Outstanding TCE/PTE */  in rtas_error_rc()
537 			rc = -EEXIST;  in rtas_error_rc()
539 		case -9002:		/* No usable slot */  in rtas_error_rc()
540 			rc = -ENODEV;  in rtas_error_rc()
543 			printk(KERN_ERR "%s: unexpected RTAS error %d\n",  in rtas_error_rc()
545 			rc = -ERANGE;  in rtas_error_rc()
553 	int token = rtas_token("get-power-level");  in rtas_get_power_level()
557 		return -ENOENT;  in rtas_get_power_level()
570 	int token = rtas_token("set-power-level");  in rtas_set_power_level()
574 		return -ENOENT;  in rtas_set_power_level()
588 	int token = rtas_token("get-sensor-state");  in rtas_get_sensor()
592 		return -ENOENT;  in rtas_get_sensor()
606 	int token = rtas_token("get-sensor-state");  in rtas_get_sensor_fast()
610 		return -ENOENT;  in rtas_get_sensor_fast()
629 	indicators = of_get_property(rtas.dev, "rtas-indicators", &proplen);  in rtas_indicator_present()
649 	int token = rtas_token("set-indicator");  in rtas_set_indicator()
653 		return -ENOENT;  in rtas_set_indicator()
666  * Ignoring RTAS extended delay
671 	int token = rtas_token("set-indicator");  in rtas_set_indicator_fast()
674 		return -ENOENT;  in rtas_set_indicator_fast()
691 	printk("RTAS system-reboot returned %d\n",  in rtas_restart()
692 	       rtas_call(rtas_token("system-reboot"), 0, 1, NULL));  in rtas_restart()
701 	printk("RTAS power-off returned %d\n",  in rtas_power_off()
702 	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));  in rtas_power_off()
711 	printk("RTAS power-off returned %d\n",  in rtas_halt()
712 	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));  in rtas_halt()
724 	 * Firmware with the ibm,extended-os-term property is guaranteed  in rtas_os_term()
725 	 * to always return from an ibm,os-term call. Earlier versions without  in rtas_os_term()
729 	if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||  in rtas_os_term()
730 	    RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))  in rtas_os_term()
736 		status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,  in rtas_os_term()
741 		printk(KERN_EMERG "ibm,os-term call failed %d\n", status);  in rtas_os_term()
753 	printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n", smp_processor_id());  in __rtas_suspend_last_cpu()
755 	while (rc == H_MULTI_THREADS_ACTIVE && !atomic_read(&data->done) &&  in __rtas_suspend_last_cpu()
756 	       !atomic_read(&data->error))  in __rtas_suspend_last_cpu()
757 		rc = rtas_call(data->token, 0, 1, NULL);  in __rtas_suspend_last_cpu()
759 	if (rc || atomic_read(&data->error)) {  in __rtas_suspend_last_cpu()
760 		printk(KERN_DEBUG "ibm,suspend-me returned %d\n", rc);  in __rtas_suspend_last_cpu()
764 	if (atomic_read(&data->error))  in __rtas_suspend_last_cpu()
765 		rc = atomic_read(&data->error);  in __rtas_suspend_last_cpu()
767 	atomic_set(&data->error, rc);  in __rtas_suspend_last_cpu()
771 		atomic_set(&data->done, 1);  in __rtas_suspend_last_cpu()
777 	if (atomic_dec_return(&data->working) == 0)  in __rtas_suspend_last_cpu()
778 		complete(data->complete);  in __rtas_suspend_last_cpu()
785 	atomic_inc(&data->working);  in rtas_suspend_last_cpu()
795 	atomic_inc(&data->working);  in __rtas_suspend_cpu()
801 	while (rc == H_SUCCESS && !atomic_read(&data->done) && !atomic_read(&data->error))  in __rtas_suspend_cpu()
817 		atomic_set(&data->error, rc);  in __rtas_suspend_cpu()
821 		atomic_set(&data->done, 1);  in __rtas_suspend_cpu()
831 	if (atomic_dec_return(&data->working) == 0)  in __rtas_suspend_cpu()
832 		complete(data->complete);  in __rtas_suspend_cpu()
854 	if (!rtas_service_present("ibm,suspend-me"))  in rtas_ibm_suspend_me()
855 		return -ENOSYS;  in rtas_ibm_suspend_me()
866 		return -EAGAIN;  in rtas_ibm_suspend_me()
870 		return -EIO;  in rtas_ibm_suspend_me()
876 	data.token = rtas_token("ibm,suspend-me");  in rtas_ibm_suspend_me()
884 	 * rtas call  in rtas_ibm_suspend_me()
902  * rtas_call_reentrant() - Used for reentrant rtas calls
903  * @token:	Token for desired reentrant RTAS call
907  * @...:	Inputs for desired RTAS call
909  * According to LoPAR documentation, only "ibm,int-on", "ibm,int-off",
910  * "ibm,get-xive" and "ibm,set-xive" are currently reentrant.
911  * Reentrant calls need their own rtas_args buffer, so not using rtas.args, but
914  * Return:	-1 on error,
915  *		First output value of RTAS call if (nret > 0),
925 	if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE)  in rtas_call_reentrant()
926 		return -1;  in rtas_call_reentrant()
931 	/* We use the per-cpu (PACA) rtas args buffer */  in rtas_call_reentrant()
932 	args = local_paca->rtas_args_reentrant;  in rtas_call_reentrant()
939 		for (i = 0; i < nret - 1; ++i)  in rtas_call_reentrant()
940 			outputs[i] = be32_to_cpu(args->rets[i + 1]);  in rtas_call_reentrant()
943 		ret = be32_to_cpu(args->rets[0]);  in rtas_call_reentrant()
954 	return -ENOSYS;  in rtas_ibm_suspend_me()
959  * Find a specific pseries error log in an RTAS extended event log.
960  * @log: RTAS error/event log
969 		(struct rtas_ext_event_log_v6 *)log->buffer;  in get_pseries_errorlog()
982 	log_end = log->buffer + ext_log_length;  in get_pseries_errorlog()
983 	p = ext_log->vendor_log;  in get_pseries_errorlog()
999  * arbitrary physical addresses to RTAS calls. A number of RTAS calls
1002  * be used inside the kernel and not exposed to userspace.
1006  * subset of RTAS calls.
1008  * Accordingly, we filter RTAS requests to check that the call is
1017 	/* Indexes into the args buffer, -1 if not used */
1027 	{ "ibm,activate-firmware", -1, -1, -1, -1, -1 },
1028 	{ "ibm,configure-connector", -1, 0, -1, 1, -1, 4096 },	/* Special cased */
1029 	{ "display-character", -1, -1, -1, -1, -1 },
1030 	{ "ibm,display-message", -1, 0, -1, -1, -1 },
1031 	{ "ibm,errinjct", -1, 2, -1, -1, -1, 1024 },
1032 	{ "ibm,close-errinjct", -1, -1, -1, -1, -1 },
1033 	{ "ibm,open-errinct", -1, -1, -1, -1, -1 },
1034 	{ "ibm,get-config-addr-info2", -1, -1, -1, -1, -1 },
1035 	{ "ibm,get-dynamic-sensor-state", -1, 1, -1, -1, -1 },
1036 	{ "ibm,get-indices", -1, 2, 3, -1, -1 },
1037 	{ "get-power-level", -1, -1, -1, -1, -1 },
1038 	{ "get-sensor-state", -1, -1, -1, -1, -1 },
1039 	{ "ibm,get-system-parameter", -1, 1, 2, -1, -1 },
1040 	{ "get-time-of-day", -1, -1, -1, -1, -1 },
1041 	{ "ibm,get-vpd", -1, 0, -1, 1, 2 },
1042 	{ "ibm,lpar-perftools", -1, 2, 3, -1, -1 },
1043 	{ "ibm,platform-dump", -1, 4, 5, -1, -1 },
1044 	{ "ibm,read-slot-reset-state", -1, -1, -1, -1, -1 },
1045 	{ "ibm,scan-log-dump", -1, 0, 1, -1, -1 },
1046 	{ "ibm,set-dynamic-indicator", -1, 2, -1, -1, -1 },
1047 	{ "ibm,set-eeh-option", -1, -1, -1, -1, -1 },
1048 	{ "set-indicator", -1, -1, -1, -1, -1 },
1049 	{ "set-power-level", -1, -1, -1, -1, -1 },
1050 	{ "set-time-for-power-on", -1, -1, -1, -1, -1 },
1051 	{ "ibm,set-system-parameter", -1, 1, -1, -1, -1 },
1052 	{ "set-time-of-day", -1, -1, -1, -1, -1 },
1053 	{ "ibm,suspend-me", -1, -1, -1, -1, -1 },
1054 	{ "ibm,update-nodes", -1, 0, -1, -1, -1, 4096 },
1055 	{ "ibm,update-properties", -1, 0, -1, -1, -1, 4096 },
1056 	{ "ibm,physical-attestation", -1, 0, 1, -1, -1 },
1077 		if (token != f->token)  in block_rtas_call()
1080 		if (f->buf_idx1 != -1) {  in block_rtas_call()
1081 			base = be32_to_cpu(args->args[f->buf_idx1]);  in block_rtas_call()
1082 			if (f->size_idx1 != -1)  in block_rtas_call()
1083 				size = be32_to_cpu(args->args[f->size_idx1]);  in block_rtas_call()
1084 			else if (f->fixed_size)  in block_rtas_call()
1085 				size = f->fixed_size;  in block_rtas_call()
1089 			end = base + size - 1;  in block_rtas_call()
1094 		if (f->buf_idx2 != -1) {  in block_rtas_call()
1095 			base = be32_to_cpu(args->args[f->buf_idx2]);  in block_rtas_call()
1096 			if (f->size_idx2 != -1)  in block_rtas_call()
1097 				size = be32_to_cpu(args->args[f->size_idx2]);  in block_rtas_call()
1098 			else if (f->fixed_size)  in block_rtas_call()
1099 				size = f->fixed_size;  in block_rtas_call()
1102 			end = base + size - 1;  in block_rtas_call()
1105 			 * Special case for ibm,configure-connector where the  in block_rtas_call()
1108 			if (!strcmp(f->name, "ibm,configure-connector") &&  in block_rtas_call()
1120 	pr_err_ratelimited("sys_rtas: RTAS call blocked - exploit attempt?\n");  in block_rtas_call()
1121 	pr_err_ratelimited("sys_rtas: token=0x%x, nargs=%d (called by %s)\n",  in block_rtas_call()
1122 			   token, nargs, current->comm);  in block_rtas_call()
1137 SYSCALL_DEFINE1(rtas, struct rtas_args __user *, uargs)  in SYSCALL_DEFINE1()  argument
1145 		return -EPERM;  in SYSCALL_DEFINE1()
1147 	if (!rtas.entry)  in SYSCALL_DEFINE1()
1148 		return -EINVAL;  in SYSCALL_DEFINE1()
1151 		return -EFAULT;  in SYSCALL_DEFINE1()
1160 		return -EINVAL;  in SYSCALL_DEFINE1()
1163 	if (copy_from_user(args.args, uargs->args,  in SYSCALL_DEFINE1()
1165 		return -EFAULT;  in SYSCALL_DEFINE1()
1168 		return -EINVAL;  in SYSCALL_DEFINE1()
1174 		return -EINVAL;  in SYSCALL_DEFINE1()
1187 		if (rc == -EAGAIN)  in SYSCALL_DEFINE1()
1189 		else if (rc == -EIO)  in SYSCALL_DEFINE1()
1190 			args.rets[0] = cpu_to_be32(-1);  in SYSCALL_DEFINE1()
1200 	rtas.args = args;  in SYSCALL_DEFINE1()
1201 	enter_rtas(__pa(&rtas.args));  in SYSCALL_DEFINE1()
1202 	args = rtas.args;  in SYSCALL_DEFINE1()
1204 	/* A -1 return code indicates that the last command couldn't  in SYSCALL_DEFINE1()
1206 	if (be32_to_cpu(args.rets[0]) == -1)  in SYSCALL_DEFINE1()
1219 	if (copy_to_user(uargs->args + nargs,  in SYSCALL_DEFINE1()
1222 		return -EFAULT;  in SYSCALL_DEFINE1()
1228  * Call early during boot, before mem init, to retrieve the RTAS
1229  * information from the device-tree and allocate the RMO buffer for userland
1241 	/* Get RTAS dev node and fill up our "rtas" structure with infos  in rtas_initialize()
1244 	rtas.dev = of_find_node_by_name(NULL, "rtas");  in rtas_initialize()
1245 	if (!rtas.dev)  in rtas_initialize()
1248 	no_base = of_property_read_u32(rtas.dev, "linux,rtas-base", &base);  in rtas_initialize()
1249 	no_size = of_property_read_u32(rtas.dev, "rtas-size", &size);  in rtas_initialize()
1251 		of_node_put(rtas.dev);  in rtas_initialize()
1252 		rtas.dev = NULL;  in rtas_initialize()
1256 	rtas.base = base;  in rtas_initialize()
1257 	rtas.size = size;  in rtas_initialize()
1258 	no_entry = of_property_read_u32(rtas.dev, "linux,rtas-entry", &entry);  in rtas_initialize()
1259 	rtas.entry = no_entry ? rtas.base : entry;  in rtas_initialize()
1261 	/* If RTAS was found, allocate the RMO buffer for it and look for  in rtas_initialize()
1262 	 * the stop-self token if any  in rtas_initialize()
1267 		ibm_suspend_me_token = rtas_token("ibm,suspend-me");  in rtas_initialize()
1273 		panic("ERROR: RTAS: Failed to allocate %lx bytes below %pa\n",  in rtas_initialize()
1277 	rtas_last_error_token = rtas_token("rtas-last-error");  in rtas_initialize()
1292 	if (depth != 1 || strcmp(uname, "rtas") != 0)  in early_init_dt_scan_rtas()
1295 	basep  = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);  in early_init_dt_scan_rtas()
1296 	entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);  in early_init_dt_scan_rtas()
1297 	sizep  = of_get_flat_dt_prop(node, "rtas-size", NULL);  in early_init_dt_scan_rtas()
1300 		rtas.base = *basep;  in early_init_dt_scan_rtas()
1301 		rtas.entry = *entryp;  in early_init_dt_scan_rtas()
1302 		rtas.size = *sizep;  in early_init_dt_scan_rtas()
1306 	basep = of_get_flat_dt_prop(node, "put-term-char", NULL);  in early_init_dt_scan_rtas()
1310 	basep = of_get_flat_dt_prop(node, "get-term-char", NULL);  in early_init_dt_scan_rtas()
1334 	rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);  in rtas_give_timebase()
1340 	rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);  in rtas_give_timebase()