1 // SPDX-License-Identifier: GPL-2.0-only
5  *    Copyright (C) 2005-2006 Thibaut VARENE <varenet@parisc-linux.org>
14  *    all) PA-RISC machines should have them. Anyway, for safety reasons, the
18  *    One last word: there's one path we can always count on: the primary path.
19  *    Anything above 224 bytes is used for 'osdep2' OS-dependent storage area.
21  *    The first OS-dependent area should always be available. Obviously, this is
24  *    NOTE: We do not handle the 2 bytes OS-dep area at 0x5D, nor the first
26  *    sacrificed: -ETOOLAZY :P
29  *	- write: root only
30  *	- read: (reading triggers PDC calls) ? root only : everyone
34  *	- timer/fastsize write calls
74 MODULE_AUTHOR("Thibaut VARENE <varenet@parisc-linux.org>");
127  * pdcspath_fetch - This function populates the path entry structs.
136  * This function expects to be called with @entry->rw_lock write-hold.
144 		return -EINVAL;  in pdcspath_fetch()
146 	devpath = &entry->devpath;  in pdcspath_fetch()
149 			entry, devpath, entry->addr);  in pdcspath_fetch()
152 	if (pdc_stable_read(entry->addr, devpath, sizeof(*devpath)) != PDC_OK)  in pdcspath_fetch()
153 		return -EIO;  in pdcspath_fetch()
158 	entry->dev = hwpath_to_device((struct hardware_path *)devpath);  in pdcspath_fetch()
160 	entry->ready = 1;  in pdcspath_fetch()
162 	DPRINTK("%s: device: 0x%p\n", __func__, entry->dev);  in pdcspath_fetch()
168  * pdcspath_store - This function writes a path to stable storage.
177  * This function expects to be called with @entry->rw_lock write-hold.
186 	devpath = &entry->devpath;  in pdcspath_store()
191 	if (!entry->ready) {  in pdcspath_store()
193 		BUG_ON(!entry->dev);  in pdcspath_store()
194 		device_to_hwpath(entry->dev, (struct hardware_path *)devpath);  in pdcspath_store()
199 			entry, devpath, entry->addr);  in pdcspath_store()
202 	if (pdc_stable_write(entry->addr, devpath, sizeof(*devpath)) != PDC_OK)  in pdcspath_store()
208 	entry->ready = 2;  in pdcspath_store()
210 	DPRINTK("%s: device: 0x%p\n", __func__, entry->dev);  in pdcspath_store()
214  * pdcspath_hwpath_read - This function handles hardware path pretty printing.
228 		return -EINVAL;  in pdcspath_hwpath_read()
230 	read_lock(&entry->rw_lock);  in pdcspath_hwpath_read()
231 	devpath = &entry->devpath;  in pdcspath_hwpath_read()
232 	i = entry->ready;  in pdcspath_hwpath_read()
233 	read_unlock(&entry->rw_lock);  in pdcspath_hwpath_read()
236 		return -ENODATA;  in pdcspath_hwpath_read()
239 		if (devpath->path.bc[i] < 0)  in pdcspath_hwpath_read()
241 		out += sprintf(out, "%d/", devpath->path.bc[i]);  in pdcspath_hwpath_read()
243 	out += sprintf(out, "%u\n", (unsigned char)devpath->path.mod);  in pdcspath_hwpath_read()
245 	return out - buf;  in pdcspath_hwpath_read()
249  * pdcspath_hwpath_write - This function handles hardware path modifying.
255  * Hardware paths are to be given '/'-delimited, without brackets.
273 		return -EINVAL;  in pdcspath_hwpath_write()
276 	count = min_t(size_t, count, sizeof(in)-1);  in pdcspath_hwpath_write()
284 		return -EINVAL;  in pdcspath_hwpath_write()
287 	in[temp-in] = '\0';	/* truncate the remaining string. just precaution */  in pdcspath_hwpath_write()
291 	   we write the bc fields in a down-top way. No matter what, we stop  in pdcspath_hwpath_write()
295 	for (i=5; ((temp = strrchr(in, '/'))) && (temp-in > 0) && (likely(i)); i--) {  in pdcspath_hwpath_write()
297 		in[temp-in] = '\0';  in pdcspath_hwpath_write()
308 			"hardware path: %s\n", __func__, entry->name, buf);  in pdcspath_hwpath_write()
309 		return -EINVAL;  in pdcspath_hwpath_write()
313 	write_lock(&entry->rw_lock);  in pdcspath_hwpath_write()
314 	entry->ready = 0;  in pdcspath_hwpath_write()
315 	entry->dev = dev;  in pdcspath_hwpath_write()
321 	sysfs_remove_link(&entry->kobj, "device");  in pdcspath_hwpath_write()
322 	write_unlock(&entry->rw_lock);  in pdcspath_hwpath_write()
324 	ret = sysfs_create_link(&entry->kobj, &entry->dev->kobj, "device");  in pdcspath_hwpath_write()
328 		entry->name, buf);  in pdcspath_hwpath_write()
334  * pdcspath_layer_read - Extended layer (eg. SCSI ids) pretty printing.
338  * We will call this function to format the output of the layer attribute file.
348 		return -EINVAL;  in pdcspath_layer_read()
350 	read_lock(&entry->rw_lock);  in pdcspath_layer_read()
351 	devpath = &entry->devpath;  in pdcspath_layer_read()
352 	i = entry->ready;  in pdcspath_layer_read()
353 	read_unlock(&entry->rw_lock);  in pdcspath_layer_read()
356 		return -ENODATA;  in pdcspath_layer_read()
358 	for (i = 0; i < 6 && devpath->layers[i]; i++)  in pdcspath_layer_read()
359 		out += sprintf(out, "%u ", devpath->layers[i]);  in pdcspath_layer_read()
363 	return out - buf;  in pdcspath_layer_read()
367  * pdcspath_layer_write - This function handles extended layer modifying.
372  * We will call this function to change the current layer value.
373  * Layers are to be given '.'-delimited, without brackets.
376  * the layer fields.
381 	unsigned int layers[6]; /* device-specific info (ctlr#, unit#, ...) */  in pdcspath_layer_write()
386 		return -EINVAL;  in pdcspath_layer_write()
389 	count = min_t(size_t, count, sizeof(in)-1);  in pdcspath_layer_write()
395 	/* First, pick the first layer */  in pdcspath_layer_write()
397 		return -EINVAL;  in pdcspath_layer_write()
399 	DPRINTK("%s: layer[0]: %d\n", __func__, layers[0]);  in pdcspath_layer_write()
404 			return -EINVAL;  in pdcspath_layer_write()
406 		DPRINTK("%s: layer[%d]: %d\n", __func__, i, layers[i]);  in pdcspath_layer_write()
410 	write_lock(&entry->rw_lock);  in pdcspath_layer_write()
414 	memcpy(&entry->devpath.layers, &layers, sizeof(layers));  in pdcspath_layer_write()
418 	write_unlock(&entry->rw_lock);  in pdcspath_layer_write()
421 		entry->name, buf);  in pdcspath_layer_write()
427  * pdcspath_attr_show - Generic read function call wrapper.
439 	if (pdcs_attr->show)  in pdcspath_attr_show()
440 		ret = pdcs_attr->show(entry, buf);  in pdcspath_attr_show()
446  * pdcspath_attr_store - Generic write function call wrapper.
461 		return -EACCES;  in pdcspath_attr_store()
463 	if (pdcs_attr->store)  in pdcspath_attr_store()
464 		ret = pdcs_attr->store(entry, buf, count);  in pdcspath_attr_store()
476 static PATHS_ATTR(layer, 0644, pdcspath_layer_read, pdcspath_layer_write);
492 static PDCSPATH_ENTRY(PDCS_ADDR_PPRI, primary);
511  * pdcs_size_read - Stable Storage size output.
523 		return -EINVAL;  in pdcs_size_read()
528 	return out - buf;  in pdcs_size_read()
532  * pdcs_auto_read - Stable Storage autoboot/search flag output.
546 		return -EINVAL;  in pdcs_auto_read()
548 	/* Current flags are stored in primary boot path entry */  in pdcs_auto_read()
551 	read_lock(&pathentry->rw_lock);  in pdcs_auto_read()
552 	out += sprintf(out, "%s\n", (pathentry->devpath.path.flags & knob) ?  in pdcs_auto_read()
554 	read_unlock(&pathentry->rw_lock);  in pdcs_auto_read()
556 	return out - buf;  in pdcs_auto_read()
560  * pdcs_autoboot_read - Stable Storage autoboot flag output.
572  * pdcs_autosearch_read - Stable Storage autoboot flag output.
584  * pdcs_timer_read - Stable Storage timer count output (in seconds).
598 		return -EINVAL;  in pdcs_timer_read()
600 	/* Current flags are stored in primary boot path entry */  in pdcs_timer_read()
604 	read_lock(&pathentry->rw_lock);  in pdcs_timer_read()
605 	out += sprintf(out, "%u\n", (pathentry->devpath.path.flags & PF_TIMER) ?  in pdcs_timer_read()
606 				(1 << (pathentry->devpath.path.flags & PF_TIMER)) : 0);  in pdcs_timer_read()
607 	read_unlock(&pathentry->rw_lock);  in pdcs_timer_read()
609 	return out - buf;  in pdcs_timer_read()
613  * pdcs_osid_read - Stable Storage OS ID register output.
624 		return -EINVAL;  in pdcs_osid_read()
629 	return out - buf;  in pdcs_osid_read()
633  * pdcs_osdep1_read - Stable Storage OS-Dependent data area 1 output.
638  * This can hold 16 bytes of OS-Dependent data.
647 		return -EINVAL;  in pdcs_osdep1_read()
650 		return -EIO;  in pdcs_osdep1_read()
657 	return out - buf;  in pdcs_osdep1_read()
661  * pdcs_diagnostic_read - Stable Storage Diagnostic register output.
666  * I have NFC how to interpret the content of that register ;-).
675 		return -EINVAL;  in pdcs_diagnostic_read()
679 		return -EIO;  in pdcs_diagnostic_read()
683 	return out - buf;  in pdcs_diagnostic_read()
687  * pdcs_fastsize_read - Stable Storage FastSize register output.
701 		return -EINVAL;  in pdcs_fastsize_read()
703 	/* get fast-size */  in pdcs_fastsize_read()
705 		return -EIO;  in pdcs_fastsize_read()
713 	return out - buf;  in pdcs_fastsize_read()
717  * pdcs_osdep2_read - Stable Storage OS-Dependent data area 2 output.
722  * This can hold pdcs_size - 224 bytes of OS-Dependent data, when available.
733 		return -ENODATA;  in pdcs_osdep2_read()
735 	size = pdcs_size - 224;  in pdcs_osdep2_read()
738 		return -EINVAL;  in pdcs_osdep2_read()
743 			return -EIO;  in pdcs_osdep2_read()
747 	return out - buf;  in pdcs_osdep2_read()
751  * pdcs_auto_write - This function handles autoboot/search flag modifying.
772 		return -EACCES;  in pdcs_auto_write()
775 		return -EINVAL;  in pdcs_auto_write()
778 	count = min_t(size_t, count, sizeof(in)-1);  in pdcs_auto_write()
781 	/* Current flags are stored in primary boot path entry */  in pdcs_auto_write()
785 	read_lock(&pathentry->rw_lock);  in pdcs_auto_write()
786 	flags = pathentry->devpath.path.flags;  in pdcs_auto_write()
787 	read_unlock(&pathentry->rw_lock);  in pdcs_auto_write()
793 	c = *temp++ - '0';  in pdcs_auto_write()
804 	write_lock(&pathentry->rw_lock);  in pdcs_auto_write()
807 	pathentry->devpath.path.flags = flags;  in pdcs_auto_write()
811 	write_unlock(&pathentry->rw_lock);  in pdcs_auto_write()
821 	return -EINVAL;  in pdcs_auto_write()
825  * pdcs_autoboot_write - This function handles autoboot flag modifying.
843  * pdcs_autosearch_write - This function handles autosearch flag modifying.
861  * pdcs_osdep1_write - Stable Storage OS-Dependent data area 1 input.
867  * This can store 16 bytes of OS-Dependent data. We use a byte-by-byte
878 		return -EACCES;  in pdcs_osdep1_write()
881 		return -EINVAL;  in pdcs_osdep1_write()
884 		return -EPERM;  in pdcs_osdep1_write()
887 		return -EMSGSIZE;  in pdcs_osdep1_write()
894 		return -EIO;  in pdcs_osdep1_write()
900  * pdcs_osdep2_write - Stable Storage OS-Dependent data area 2 input.
906  * This can store pdcs_size - 224 bytes of OS-Dependent data. We use a
907  * byte-by-byte write approach. It's up to userspace to deal with it when
919 		return -EACCES;  in pdcs_osdep2_write()
922 		return -EINVAL;  in pdcs_osdep2_write()
925 		return -ENOSYS;  in pdcs_osdep2_write()
928 		return -EPERM;  in pdcs_osdep2_write()
930 	size = pdcs_size - 224;  in pdcs_osdep2_write()
933 		return -EMSGSIZE;  in pdcs_osdep2_write()
939 		memcpy(in, buf+i, (count-i < 4) ? count-i : 4);  in pdcs_osdep2_write()
942 			return -EIO;  in pdcs_osdep2_write()
980  * pdcs_register_pathentries - Prepares path entries kobjects for sysfs usage.
997 		rwlock_init(&entry->rw_lock);  in pdcs_register_pathentries()
1000 		write_lock(&entry->rw_lock);  in pdcs_register_pathentries()
1002 		write_unlock(&entry->rw_lock);  in pdcs_register_pathentries()
1007 		entry->kobj.kset = paths_kset;  in pdcs_register_pathentries()
1008 		err = kobject_init_and_add(&entry->kobj, &ktype_pdcspath, NULL,  in pdcs_register_pathentries()
1009 					   "%s", entry->name);  in pdcs_register_pathentries()
1011 			kobject_put(&entry->kobj);  in pdcs_register_pathentries()
1016 		write_lock(&entry->rw_lock);  in pdcs_register_pathentries()
1017 		entry->ready = 2;  in pdcs_register_pathentries()
1018 		write_unlock(&entry->rw_lock);  in pdcs_register_pathentries()
1021 		if (entry->dev) {  in pdcs_register_pathentries()
1022 			err = sysfs_create_link(&entry->kobj, &entry->dev->kobj, "device");  in pdcs_register_pathentries()
1026 		kobject_uevent(&entry->kobj, KOBJ_ADD);  in pdcs_register_pathentries()
1033  * pdcs_unregister_pathentries - Routine called when unregistering the module.
1042 		read_lock(&entry->rw_lock);  in pdcs_unregister_pathentries()
1043 		if (entry->ready >= 2)  in pdcs_unregister_pathentries()
1044 			kobject_put(&entry->kobj);  in pdcs_unregister_pathentries()
1045 		read_unlock(&entry->rw_lock);  in pdcs_unregister_pathentries()
1061 		return -ENODEV;  in pdc_stable_init()
1065 		return -ENODATA;  in pdc_stable_init()
1071 		return -EIO;  in pdc_stable_init()
1079 		rc = -ENOMEM;  in pdc_stable_init()
1086 		rc = -ENOMEM;  in pdc_stable_init()
1093 		rc = -ENOMEM;  in pdc_stable_init()