xref: /linux/drivers/pci/hotplug/rpaphp_core.c (revision 4dc7ccf7e9d9bca1989b840be9e8e84911387cf2)
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/smp.h>
31 #include <linux/init.h>
32 #include <asm/eeh.h>       /* for eeh_add_device() */
33 #include <asm/rtas.h>		/* rtas_call */
34 #include <asm/pci-bridge.h>	/* for pci_controller */
35 #include "../pci.h"		/* for pci_add_new_bus */
36 				/* and pci_do_scan_bus */
37 #include "rpaphp.h"
38 
39 int rpaphp_debug;
40 LIST_HEAD(rpaphp_slot_head);
41 
42 #define DRIVER_VERSION	"0.1"
43 #define DRIVER_AUTHOR	"Linda Xie <lxie@us.ibm.com>"
44 #define DRIVER_DESC	"RPA HOT Plug PCI Controller Driver"
45 
46 #define MAX_LOC_CODE 128
47 
48 MODULE_AUTHOR(DRIVER_AUTHOR);
49 MODULE_DESCRIPTION(DRIVER_DESC);
50 MODULE_LICENSE("GPL");
51 
52 module_param_named(debug, rpaphp_debug, bool, 0644);
53 
54 /**
55  * set_attention_status - set attention LED
56  * @hotplug_slot: target &hotplug_slot
57  * @value: LED control value
58  *
59  * echo 0 > attention -- set LED OFF
60  * echo 1 > attention -- set LED ON
61  * echo 2 > attention -- set LED ID(identify, light is blinking)
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  * @hotplug_slot: slot to get status
104  * @value: pointer to store status
105  */
106 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
107 {
108 	struct slot *slot = (struct slot *)hotplug_slot->private;
109 	*value = slot->hotplug_slot->info->attention_status;
110 	return 0;
111 }
112 
113 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
114 {
115 	struct slot *slot = (struct slot *)hotplug_slot->private;
116 	int rc, state;
117 
118 	rc = rpaphp_get_sensor_state(slot, &state);
119 
120 	*value = NOT_VALID;
121 	if (rc)
122 		return rc;
123 
124 	if (state == EMPTY)
125 		*value = EMPTY;
126 	else if (state == PRESENT)
127 		*value = slot->state;
128 
129 	return 0;
130 }
131 
132 static enum pci_bus_speed get_max_bus_speed(struct slot *slot)
133 {
134 	enum pci_bus_speed speed;
135 	switch (slot->type) {
136 	case 1:
137 	case 2:
138 	case 3:
139 	case 4:
140 	case 5:
141 	case 6:
142 		speed = PCI_SPEED_33MHz;	/* speed for case 1-6 */
143 		break;
144 	case 7:
145 	case 8:
146 		speed = PCI_SPEED_66MHz;
147 		break;
148 	case 11:
149 	case 14:
150 		speed = PCI_SPEED_66MHz_PCIX;
151 		break;
152 	case 12:
153 	case 15:
154 		speed = PCI_SPEED_100MHz_PCIX;
155 		break;
156 	case 13:
157 	case 16:
158 		speed = PCI_SPEED_133MHz_PCIX;
159 		break;
160 	default:
161 		speed = PCI_SPEED_UNKNOWN;
162 		break;
163 	}
164 
165 	return speed;
166 }
167 
168 static int get_children_props(struct device_node *dn, const int **drc_indexes,
169 		const int **drc_names, const int **drc_types,
170 		const int **drc_power_domains)
171 {
172 	const int *indexes, *names, *types, *domains;
173 
174 	indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
175 	names = of_get_property(dn, "ibm,drc-names", NULL);
176 	types = of_get_property(dn, "ibm,drc-types", NULL);
177 	domains = of_get_property(dn, "ibm,drc-power-domains", NULL);
178 
179 	if (!indexes || !names || !types || !domains) {
180 		/* Slot does not have dynamically-removable children */
181 		return -EINVAL;
182 	}
183 	if (drc_indexes)
184 		*drc_indexes = indexes;
185 	if (drc_names)
186 		/* &drc_names[1] contains NULL terminated slot names */
187 		*drc_names = names;
188 	if (drc_types)
189 		/* &drc_types[1] contains NULL terminated slot types */
190 		*drc_types = types;
191 	if (drc_power_domains)
192 		*drc_power_domains = domains;
193 
194 	return 0;
195 }
196 
197 /* To get the DRC props describing the current node, first obtain it's
198  * my-drc-index property.  Next obtain the DRC list from it's parent.  Use
199  * the my-drc-index for correlation, and obtain the requested properties.
200  */
201 int rpaphp_get_drc_props(struct device_node *dn, int *drc_index,
202 		char **drc_name, char **drc_type, int *drc_power_domain)
203 {
204 	const int *indexes, *names;
205 	const int *types, *domains;
206 	const unsigned int *my_index;
207 	char *name_tmp, *type_tmp;
208 	int i, rc;
209 
210 	my_index = of_get_property(dn, "ibm,my-drc-index", NULL);
211 	if (!my_index) {
212 		/* Node isn't DLPAR/hotplug capable */
213 		return -EINVAL;
214 	}
215 
216 	rc = get_children_props(dn->parent, &indexes, &names, &types, &domains);
217 	if (rc < 0) {
218 		return -EINVAL;
219 	}
220 
221 	name_tmp = (char *) &names[1];
222 	type_tmp = (char *) &types[1];
223 
224 	/* Iterate through parent properties, looking for my-drc-index */
225 	for (i = 0; i < indexes[0]; i++) {
226 		if ((unsigned int) indexes[i + 1] == *my_index) {
227 			if (drc_name)
228                 		*drc_name = name_tmp;
229 			if (drc_type)
230 				*drc_type = type_tmp;
231 			if (drc_index)
232 				*drc_index = *my_index;
233 			if (drc_power_domain)
234 				*drc_power_domain = domains[i+1];
235 			return 0;
236 		}
237 		name_tmp += (strlen(name_tmp) + 1);
238 		type_tmp += (strlen(type_tmp) + 1);
239 	}
240 
241 	return -EINVAL;
242 }
243 
244 static int is_php_type(char *drc_type)
245 {
246 	unsigned long value;
247 	char *endptr;
248 
249 	/* PCI Hotplug nodes have an integer for drc_type */
250 	value = simple_strtoul(drc_type, &endptr, 10);
251 	if (endptr == drc_type)
252 		return 0;
253 
254 	return 1;
255 }
256 
257 /**
258  * is_php_dn() - return 1 if this is a hotpluggable pci slot, else 0
259  * @dn: target &device_node
260  * @indexes: passed to get_children_props()
261  * @names: passed to get_children_props()
262  * @types: returned from get_children_props()
263  * @power_domains:
264  *
265  * This routine will return true only if the device node is
266  * a hotpluggable slot. This routine will return false
267  * for built-in pci slots (even when the built-in slots are
268  * dlparable.)
269  */
270 static int is_php_dn(struct device_node *dn, const int **indexes,
271 		const int **names, const int **types, const int **power_domains)
272 {
273 	const int *drc_types;
274 	int rc;
275 
276 	rc = get_children_props(dn, indexes, names, &drc_types, power_domains);
277 	if (rc < 0)
278 		return 0;
279 
280 	if (!is_php_type((char *) &drc_types[1]))
281 		return 0;
282 
283 	*types = drc_types;
284 	return 1;
285 }
286 
287 /**
288  * rpaphp_add_slot -- declare a hotplug slot to the hotplug subsystem.
289  * @dn: device node of slot
290  *
291  * This subroutine will register a hotplugable slot with the
292  * PCI hotplug infrastructure. This routine is typicaly called
293  * during boot time, if the hotplug slots are present at boot time,
294  * or is called later, by the dlpar add code, if the slot is
295  * being dynamically added during runtime.
296  *
297  * If the device node points at an embedded (built-in) slot, this
298  * routine will just return without doing anything, since embedded
299  * slots cannot be hotplugged.
300  *
301  * To remove a slot, it suffices to call rpaphp_deregister_slot().
302  */
303 int rpaphp_add_slot(struct device_node *dn)
304 {
305 	struct slot *slot;
306 	int retval = 0;
307 	int i;
308 	const int *indexes, *names, *types, *power_domains;
309 	char *name, *type;
310 
311 	if (!dn->name || strcmp(dn->name, "pci"))
312 		return 0;
313 
314 	/* If this is not a hotplug slot, return without doing anything. */
315 	if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
316 		return 0;
317 
318 	dbg("Entry %s: dn->full_name=%s\n", __func__, dn->full_name);
319 
320 	/* register PCI devices */
321 	name = (char *) &names[1];
322 	type = (char *) &types[1];
323 	for (i = 0; i < indexes[0]; i++) {
324 
325 		slot = alloc_slot_struct(dn, indexes[i + 1], name, power_domains[i + 1]);
326 		if (!slot)
327 			return -ENOMEM;
328 
329 		slot->type = simple_strtoul(type, NULL, 10);
330 
331 		dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
332 				indexes[i + 1], name, type);
333 
334 		retval = rpaphp_enable_slot(slot);
335 		if (!retval)
336 			retval = rpaphp_register_slot(slot);
337 
338 		if (retval)
339 			dealloc_slot_struct(slot);
340 
341 		name += strlen(name) + 1;
342 		type += strlen(type) + 1;
343 	}
344 	dbg("%s - Exit: rc[%d]\n", __func__, retval);
345 
346 	/* XXX FIXME: reports a failure only if last entry in loop failed */
347 	return retval;
348 }
349 
350 static void __exit cleanup_slots(void)
351 {
352 	struct list_head *tmp, *n;
353 	struct slot *slot;
354 
355 	/*
356 	 * Unregister all of our slots with the pci_hotplug subsystem,
357 	 * and free up all memory that we had allocated.
358 	 * memory will be freed in release_slot callback.
359 	 */
360 
361 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
362 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
363 		list_del(&slot->rpaphp_slot_list);
364 		pci_hp_deregister(slot->hotplug_slot);
365 	}
366 	return;
367 }
368 
369 static int __init rpaphp_init(void)
370 {
371 	struct device_node *dn = NULL;
372 
373 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
374 
375 	while ((dn = of_find_node_by_name(dn, "pci")))
376 		rpaphp_add_slot(dn);
377 
378 	return 0;
379 }
380 
381 static void __exit rpaphp_exit(void)
382 {
383 	cleanup_slots();
384 }
385 
386 static int enable_slot(struct hotplug_slot *hotplug_slot)
387 {
388 	struct slot *slot = (struct slot *)hotplug_slot->private;
389 	int state;
390 	int retval;
391 
392 	if (slot->state == CONFIGURED)
393 		return 0;
394 
395 	retval = rpaphp_get_sensor_state(slot, &state);
396 	if (retval)
397 		return retval;
398 
399 	if (state == PRESENT) {
400 		pcibios_add_pci_devices(slot->bus);
401 		slot->state = CONFIGURED;
402 	} else if (state == EMPTY) {
403 		slot->state = EMPTY;
404 	} else {
405 		err("%s: slot[%s] is in invalid state\n", __func__, slot->name);
406 		slot->state = NOT_VALID;
407 		return -EINVAL;
408 	}
409 
410 	slot->bus->max_bus_speed = get_max_bus_speed(slot);
411 	return 0;
412 }
413 
414 static int disable_slot(struct hotplug_slot *hotplug_slot)
415 {
416 	struct slot *slot = (struct slot *)hotplug_slot->private;
417 	if (slot->state == NOT_CONFIGURED)
418 		return -EINVAL;
419 
420 	pcibios_remove_pci_devices(slot->bus);
421 	slot->state = NOT_CONFIGURED;
422 	return 0;
423 }
424 
425 struct hotplug_slot_ops rpaphp_hotplug_slot_ops = {
426 	.enable_slot = enable_slot,
427 	.disable_slot = disable_slot,
428 	.set_attention_status = set_attention_status,
429 	.get_power_status = get_power_status,
430 	.get_attention_status = get_attention_status,
431 	.get_adapter_status = get_adapter_status,
432 };
433 
434 module_init(rpaphp_init);
435 module_exit(rpaphp_exit);
436 
437 EXPORT_SYMBOL_GPL(rpaphp_add_slot);
438 EXPORT_SYMBOL_GPL(rpaphp_slot_head);
439 EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
440