xref: /linux/drivers/pci/hotplug/rpaphp_core.c (revision eb2bce7f5e7ac1ca6da434461217fadf3c688d2c)
1 /*
2  * PCI Hot Plug Controller Driver for RPA-compliant PPC64 platform.
3  * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
4  *
5  * All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or (at
10  * your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15  * NON INFRINGEMENT.  See the GNU General Public License for more
16  * details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  *
22  * Send feedback to <lxie@us.ibm.com>
23  *
24  */
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/moduleparam.h>
28 #include <linux/pci.h>
29 #include <linux/pci_hotplug.h>
30 #include <linux/slab.h>
31 #include <linux/smp.h>
32 #include <linux/smp_lock.h>
33 #include <linux/init.h>
34 #include <asm/eeh.h>       /* for eeh_add_device() */
35 #include <asm/rtas.h>		/* rtas_call */
36 #include <asm/pci-bridge.h>	/* for pci_controller */
37 #include "../pci.h"		/* for pci_add_new_bus */
38 				/* and pci_do_scan_bus */
39 #include "rpaphp.h"
40 
41 int debug;
42 LIST_HEAD(rpaphp_slot_head);
43 
44 #define DRIVER_VERSION	"0.1"
45 #define DRIVER_AUTHOR	"Linda Xie <lxie@us.ibm.com>"
46 #define DRIVER_DESC	"RPA HOT Plug PCI Controller Driver"
47 
48 #define MAX_LOC_CODE 128
49 
50 MODULE_AUTHOR(DRIVER_AUTHOR);
51 MODULE_DESCRIPTION(DRIVER_DESC);
52 MODULE_LICENSE("GPL");
53 
54 module_param(debug, bool, 0644);
55 
56 /**
57  * set_attention_status - set attention LED
58  * echo 0 > attention -- set LED OFF
59  * echo 1 > attention -- set LED ON
60  * echo 2 > attention -- set LED ID(identify, light is blinking)
61  *
62  */
63 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 value)
64 {
65 	int rc;
66 	struct slot *slot = (struct slot *)hotplug_slot->private;
67 
68 	switch (value) {
69 	case 0:
70 	case 1:
71 	case 2:
72 		break;
73 	default:
74 		value = 1;
75 		break;
76 	}
77 
78 	rc = rtas_set_indicator(DR_INDICATOR, slot->index, value);
79 	if (!rc)
80 		hotplug_slot->info->attention_status = value;
81 
82 	return rc;
83 }
84 
85 /**
86  * get_power_status - get power status of a slot
87  * @hotplug_slot: slot to get status
88  * @value: pointer to store status
89  */
90 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
91 {
92 	int retval, level;
93 	struct slot *slot = (struct slot *)hotplug_slot->private;
94 
95 	retval = rtas_get_power_level (slot->power_domain, &level);
96 	if (!retval)
97 		*value = level;
98 	return retval;
99 }
100 
101 /**
102  * get_attention_status - get attention LED status
103  */
104 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
105 {
106 	struct slot *slot = (struct slot *)hotplug_slot->private;
107 	*value = slot->hotplug_slot->info->attention_status;
108 	return 0;
109 }
110 
111 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
112 {
113 	struct slot *slot = (struct slot *)hotplug_slot->private;
114 	int rc, state;
115 
116 	rc = rpaphp_get_sensor_state(slot, &state);
117 
118 	*value = NOT_VALID;
119 	if (rc)
120 		return rc;
121 
122 	if (state == EMPTY)
123 		*value = EMPTY;
124 	else if (state == PRESENT)
125 		*value = slot->state;
126 
127 	return 0;
128 }
129 
130 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
131 {
132 	struct slot *slot = (struct slot *)hotplug_slot->private;
133 
134 	switch (slot->type) {
135 	case 1:
136 	case 2:
137 	case 3:
138 	case 4:
139 	case 5:
140 	case 6:
141 		*value = PCI_SPEED_33MHz;	/* speed for case 1-6 */
142 		break;
143 	case 7:
144 	case 8:
145 		*value = PCI_SPEED_66MHz;
146 		break;
147 	case 11:
148 	case 14:
149 		*value = PCI_SPEED_66MHz_PCIX;
150 		break;
151 	case 12:
152 	case 15:
153 		*value = PCI_SPEED_100MHz_PCIX;
154 		break;
155 	case 13:
156 	case 16:
157 		*value = PCI_SPEED_133MHz_PCIX;
158 		break;
159 	default:
160 		*value = PCI_SPEED_UNKNOWN;
161 		break;
162 
163 	}
164 	return 0;
165 }
166 
167 static int get_children_props(struct device_node *dn, const int **drc_indexes,
168 		const int **drc_names, const int **drc_types,
169 		const int **drc_power_domains)
170 {
171 	const int *indexes, *names, *types, *domains;
172 
173 	indexes = get_property(dn, "ibm,drc-indexes", NULL);
174 	names = get_property(dn, "ibm,drc-names", NULL);
175 	types = get_property(dn, "ibm,drc-types", NULL);
176 	domains = get_property(dn, "ibm,drc-power-domains", NULL);
177 
178 	if (!indexes || !names || !types || !domains) {
179 		/* Slot does not have dynamically-removable children */
180 		return -EINVAL;
181 	}
182 	if (drc_indexes)
183 		*drc_indexes = indexes;
184 	if (drc_names)
185 		/* &drc_names[1] contains NULL terminated slot names */
186 		*drc_names = names;
187 	if (drc_types)
188 		/* &drc_types[1] contains NULL terminated slot types */
189 		*drc_types = types;
190 	if (drc_power_domains)
191 		*drc_power_domains = domains;
192 
193 	return 0;
194 }
195 
196 /* To get the DRC props describing the current node, first obtain it's
197  * my-drc-index property.  Next obtain the DRC list from it's parent.  Use
198  * the my-drc-index for correlation, and obtain the requested properties.
199  */
200 int rpaphp_get_drc_props(struct device_node *dn, int *drc_index,
201 		char **drc_name, char **drc_type, int *drc_power_domain)
202 {
203 	const int *indexes, *names;
204 	const int *types, *domains;
205 	const unsigned int *my_index;
206 	char *name_tmp, *type_tmp;
207 	int i, rc;
208 
209 	my_index = get_property(dn, "ibm,my-drc-index", NULL);
210 	if (!my_index) {
211 		/* Node isn't DLPAR/hotplug capable */
212 		return -EINVAL;
213 	}
214 
215 	rc = get_children_props(dn->parent, &indexes, &names, &types, &domains);
216 	if (rc < 0) {
217 		return -EINVAL;
218 	}
219 
220 	name_tmp = (char *) &names[1];
221 	type_tmp = (char *) &types[1];
222 
223 	/* Iterate through parent properties, looking for my-drc-index */
224 	for (i = 0; i < indexes[0]; i++) {
225 		if ((unsigned int) indexes[i + 1] == *my_index) {
226 			if (drc_name)
227                 		*drc_name = name_tmp;
228 			if (drc_type)
229 				*drc_type = type_tmp;
230 			if (drc_index)
231 				*drc_index = *my_index;
232 			if (drc_power_domain)
233 				*drc_power_domain = domains[i+1];
234 			return 0;
235 		}
236 		name_tmp += (strlen(name_tmp) + 1);
237 		type_tmp += (strlen(type_tmp) + 1);
238 	}
239 
240 	return -EINVAL;
241 }
242 
243 static int is_php_type(char *drc_type)
244 {
245 	unsigned long value;
246 	char *endptr;
247 
248 	/* PCI Hotplug nodes have an integer for drc_type */
249 	value = simple_strtoul(drc_type, &endptr, 10);
250 	if (endptr == drc_type)
251 		return 0;
252 
253 	return 1;
254 }
255 
256 /**
257  * is_php_dn() - return 1 if this is a hotpluggable pci slot, else 0
258  *
259  * This routine will return true only if the device node is
260  * a hotpluggable slot. This routine will return false
261  * for built-in pci slots (even when the built-in slots are
262  * dlparable.)
263  */
264 static int is_php_dn(struct device_node *dn, const int **indexes,
265 		const int **names, const int **types, const int **power_domains)
266 {
267 	const int *drc_types;
268 	int rc;
269 
270 	rc = get_children_props(dn, indexes, names, &drc_types, power_domains);
271 	if (rc < 0)
272 		return 0;
273 
274 	if (!is_php_type((char *) &drc_types[1]))
275 		return 0;
276 
277 	*types = drc_types;
278 	return 1;
279 }
280 
281 /**
282  * rpaphp_add_slot -- declare a hotplug slot to the hotplug subsystem.
283  * @dn device node of slot
284  *
285  * This subroutine will register a hotplugable slot with the
286  * PCI hotplug infrastructure. This routine is typicaly called
287  * during boot time, if the hotplug slots are present at boot time,
288  * or is called later, by the dlpar add code, if the slot is
289  * being dynamically added during runtime.
290  *
291  * If the device node points at an embedded (built-in) slot, this
292  * routine will just return without doing anything, since embedded
293  * slots cannot be hotplugged.
294  *
295  * To remove a slot, it suffices to call rpaphp_deregister_slot()
296  */
297 int rpaphp_add_slot(struct device_node *dn)
298 {
299 	struct slot *slot;
300 	int retval = 0;
301 	int i;
302 	const int *indexes, *names, *types, *power_domains;
303 	char *name, *type;
304 
305 	if (!dn->name || strcmp(dn->name, "pci"))
306 		return 0;
307 
308 	/* If this is not a hotplug slot, return without doing anything. */
309 	if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
310 		return 0;
311 
312 	dbg("Entry %s: dn->full_name=%s\n", __FUNCTION__, dn->full_name);
313 
314 	/* register PCI devices */
315 	name = (char *) &names[1];
316 	type = (char *) &types[1];
317 	for (i = 0; i < indexes[0]; i++) {
318 
319 		slot = alloc_slot_struct(dn, indexes[i + 1], name, power_domains[i + 1]);
320 		if (!slot)
321 			return -ENOMEM;
322 
323 		slot->type = simple_strtoul(type, NULL, 10);
324 
325 		dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
326 				indexes[i + 1], name, type);
327 
328 		retval = rpaphp_enable_slot(slot);
329 		if (!retval)
330 			retval = rpaphp_register_slot(slot);
331 
332 		if (retval)
333 			dealloc_slot_struct(slot);
334 
335 		name += strlen(name) + 1;
336 		type += strlen(type) + 1;
337 	}
338 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
339 
340 	/* XXX FIXME: reports a failure only if last entry in loop failed */
341 	return retval;
342 }
343 
344 static void __exit cleanup_slots(void)
345 {
346 	struct list_head *tmp, *n;
347 	struct slot *slot;
348 
349 	/*
350 	 * Unregister all of our slots with the pci_hotplug subsystem,
351 	 * and free up all memory that we had allocated.
352 	 * memory will be freed in release_slot callback.
353 	 */
354 
355 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
356 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
357 		list_del(&slot->rpaphp_slot_list);
358 		pci_hp_deregister(slot->hotplug_slot);
359 	}
360 	return;
361 }
362 
363 static int __init rpaphp_init(void)
364 {
365 	struct device_node *dn = NULL;
366 
367 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
368 
369 	while ((dn = of_find_node_by_name(dn, "pci")))
370 		rpaphp_add_slot(dn);
371 
372 	return 0;
373 }
374 
375 static void __exit rpaphp_exit(void)
376 {
377 	cleanup_slots();
378 }
379 
380 static int enable_slot(struct hotplug_slot *hotplug_slot)
381 {
382 	struct slot *slot = (struct slot *)hotplug_slot->private;
383 	int state;
384 	int retval;
385 
386 	if (slot->state == CONFIGURED)
387 		return 0;
388 
389 	retval = rpaphp_get_sensor_state(slot, &state);
390 	if (retval)
391 		return retval;
392 
393 	if (state == PRESENT) {
394 		pcibios_add_pci_devices(slot->bus);
395 		slot->state = CONFIGURED;
396 	} else if (state == EMPTY) {
397 		slot->state = EMPTY;
398 	} else {
399 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__, slot->name);
400 		slot->state = NOT_VALID;
401 		return -EINVAL;
402 	}
403 	return 0;
404 }
405 
406 static int disable_slot(struct hotplug_slot *hotplug_slot)
407 {
408 	struct slot *slot = (struct slot *)hotplug_slot->private;
409 	if (slot->state == NOT_CONFIGURED)
410 		return -EINVAL;
411 
412 	pcibios_remove_pci_devices(slot->bus);
413 	slot->state = NOT_CONFIGURED;
414 	return 0;
415 }
416 
417 struct hotplug_slot_ops rpaphp_hotplug_slot_ops = {
418 	.owner = THIS_MODULE,
419 	.enable_slot = enable_slot,
420 	.disable_slot = disable_slot,
421 	.set_attention_status = set_attention_status,
422 	.get_power_status = get_power_status,
423 	.get_attention_status = get_attention_status,
424 	.get_adapter_status = get_adapter_status,
425 	.get_max_bus_speed = get_max_bus_speed,
426 };
427 
428 module_init(rpaphp_init);
429 module_exit(rpaphp_exit);
430 
431 EXPORT_SYMBOL_GPL(rpaphp_add_slot);
432 EXPORT_SYMBOL_GPL(rpaphp_slot_head);
433 EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
434