xref: /openbmc/linux/drivers/pci/hotplug/rpaphp_core.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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/init.h>
33 #include <asm/eeh.h>       /* for eeh_add_device() */
34 #include <asm/rtas.h>		/* rtas_call */
35 #include <asm/pci-bridge.h>	/* for pci_controller */
36 #include "../pci.h"		/* for pci_add_new_bus */
37 				/* and pci_do_scan_bus */
38 #include "rpaphp.h"
39 
40 int debug;
41 LIST_HEAD(rpaphp_slot_head);
42 
43 #define DRIVER_VERSION	"0.1"
44 #define DRIVER_AUTHOR	"Linda Xie <lxie@us.ibm.com>"
45 #define DRIVER_DESC	"RPA HOT Plug PCI Controller Driver"
46 
47 #define MAX_LOC_CODE 128
48 
49 MODULE_AUTHOR(DRIVER_AUTHOR);
50 MODULE_DESCRIPTION(DRIVER_DESC);
51 MODULE_LICENSE("GPL");
52 
53 module_param(debug, bool, 0644);
54 
55 /**
56  * set_attention_status - set attention LED
57  * echo 0 > attention -- set LED OFF
58  * echo 1 > attention -- set LED ON
59  * echo 2 > attention -- set LED ID(identify, light is blinking)
60  *
61  */
62 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 value)
63 {
64 	int rc;
65 	struct slot *slot = (struct slot *)hotplug_slot->private;
66 
67 	switch (value) {
68 	case 0:
69 	case 1:
70 	case 2:
71 		break;
72 	default:
73 		value = 1;
74 		break;
75 	}
76 
77 	rc = rtas_set_indicator(DR_INDICATOR, slot->index, value);
78 	if (!rc)
79 		hotplug_slot->info->attention_status = value;
80 
81 	return rc;
82 }
83 
84 /**
85  * get_power_status - get power status of a slot
86  * @hotplug_slot: slot to get status
87  * @value: pointer to store status
88  */
89 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
90 {
91 	int retval, level;
92 	struct slot *slot = (struct slot *)hotplug_slot->private;
93 
94 	retval = rtas_get_power_level (slot->power_domain, &level);
95 	if (!retval)
96 		*value = level;
97 	return retval;
98 }
99 
100 /**
101  * get_attention_status - get attention LED status
102  */
103 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
104 {
105 	struct slot *slot = (struct slot *)hotplug_slot->private;
106 	*value = slot->hotplug_slot->info->attention_status;
107 	return 0;
108 }
109 
110 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
111 {
112 	struct slot *slot = (struct slot *)hotplug_slot->private;
113 	int rc, state;
114 
115 	rc = rpaphp_get_sensor_state(slot, &state);
116 
117 	*value = NOT_VALID;
118 	if (rc)
119 		return rc;
120 
121 	if (state == EMPTY)
122 		*value = EMPTY;
123 	else if (state == PRESENT)
124 		*value = slot->state;
125 
126 	return 0;
127 }
128 
129 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
130 {
131 	struct slot *slot = (struct slot *)hotplug_slot->private;
132 
133 	switch (slot->type) {
134 	case 1:
135 	case 2:
136 	case 3:
137 	case 4:
138 	case 5:
139 	case 6:
140 		*value = PCI_SPEED_33MHz;	/* speed for case 1-6 */
141 		break;
142 	case 7:
143 	case 8:
144 		*value = PCI_SPEED_66MHz;
145 		break;
146 	case 11:
147 	case 14:
148 		*value = PCI_SPEED_66MHz_PCIX;
149 		break;
150 	case 12:
151 	case 15:
152 		*value = PCI_SPEED_100MHz_PCIX;
153 		break;
154 	case 13:
155 	case 16:
156 		*value = PCI_SPEED_133MHz_PCIX;
157 		break;
158 	default:
159 		*value = PCI_SPEED_UNKNOWN;
160 		break;
161 
162 	}
163 	return 0;
164 }
165 
166 static int get_children_props(struct device_node *dn, const int **drc_indexes,
167 		const int **drc_names, const int **drc_types,
168 		const int **drc_power_domains)
169 {
170 	const int *indexes, *names, *types, *domains;
171 
172 	indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
173 	names = of_get_property(dn, "ibm,drc-names", NULL);
174 	types = of_get_property(dn, "ibm,drc-types", NULL);
175 	domains = of_get_property(dn, "ibm,drc-power-domains", NULL);
176 
177 	if (!indexes || !names || !types || !domains) {
178 		/* Slot does not have dynamically-removable children */
179 		return -EINVAL;
180 	}
181 	if (drc_indexes)
182 		*drc_indexes = indexes;
183 	if (drc_names)
184 		/* &drc_names[1] contains NULL terminated slot names */
185 		*drc_names = names;
186 	if (drc_types)
187 		/* &drc_types[1] contains NULL terminated slot types */
188 		*drc_types = types;
189 	if (drc_power_domains)
190 		*drc_power_domains = domains;
191 
192 	return 0;
193 }
194 
195 /* To get the DRC props describing the current node, first obtain it's
196  * my-drc-index property.  Next obtain the DRC list from it's parent.  Use
197  * the my-drc-index for correlation, and obtain the requested properties.
198  */
199 int rpaphp_get_drc_props(struct device_node *dn, int *drc_index,
200 		char **drc_name, char **drc_type, int *drc_power_domain)
201 {
202 	const int *indexes, *names;
203 	const int *types, *domains;
204 	const unsigned int *my_index;
205 	char *name_tmp, *type_tmp;
206 	int i, rc;
207 
208 	my_index = of_get_property(dn, "ibm,my-drc-index", NULL);
209 	if (!my_index) {
210 		/* Node isn't DLPAR/hotplug capable */
211 		return -EINVAL;
212 	}
213 
214 	rc = get_children_props(dn->parent, &indexes, &names, &types, &domains);
215 	if (rc < 0) {
216 		return -EINVAL;
217 	}
218 
219 	name_tmp = (char *) &names[1];
220 	type_tmp = (char *) &types[1];
221 
222 	/* Iterate through parent properties, looking for my-drc-index */
223 	for (i = 0; i < indexes[0]; i++) {
224 		if ((unsigned int) indexes[i + 1] == *my_index) {
225 			if (drc_name)
226                 		*drc_name = name_tmp;
227 			if (drc_type)
228 				*drc_type = type_tmp;
229 			if (drc_index)
230 				*drc_index = *my_index;
231 			if (drc_power_domain)
232 				*drc_power_domain = domains[i+1];
233 			return 0;
234 		}
235 		name_tmp += (strlen(name_tmp) + 1);
236 		type_tmp += (strlen(type_tmp) + 1);
237 	}
238 
239 	return -EINVAL;
240 }
241 
242 static int is_php_type(char *drc_type)
243 {
244 	unsigned long value;
245 	char *endptr;
246 
247 	/* PCI Hotplug nodes have an integer for drc_type */
248 	value = simple_strtoul(drc_type, &endptr, 10);
249 	if (endptr == drc_type)
250 		return 0;
251 
252 	return 1;
253 }
254 
255 /**
256  * is_php_dn() - return 1 if this is a hotpluggable pci slot, else 0
257  *
258  * This routine will return true only if the device node is
259  * a hotpluggable slot. This routine will return false
260  * for built-in pci slots (even when the built-in slots are
261  * dlparable.)
262  */
263 static int is_php_dn(struct device_node *dn, const int **indexes,
264 		const int **names, const int **types, const int **power_domains)
265 {
266 	const int *drc_types;
267 	int rc;
268 
269 	rc = get_children_props(dn, indexes, names, &drc_types, power_domains);
270 	if (rc < 0)
271 		return 0;
272 
273 	if (!is_php_type((char *) &drc_types[1]))
274 		return 0;
275 
276 	*types = drc_types;
277 	return 1;
278 }
279 
280 /**
281  * rpaphp_add_slot -- declare a hotplug slot to the hotplug subsystem.
282  * @dn device node of slot
283  *
284  * This subroutine will register a hotplugable slot with the
285  * PCI hotplug infrastructure. This routine is typicaly called
286  * during boot time, if the hotplug slots are present at boot time,
287  * or is called later, by the dlpar add code, if the slot is
288  * being dynamically added during runtime.
289  *
290  * If the device node points at an embedded (built-in) slot, this
291  * routine will just return without doing anything, since embedded
292  * slots cannot be hotplugged.
293  *
294  * To remove a slot, it suffices to call rpaphp_deregister_slot()
295  */
296 int rpaphp_add_slot(struct device_node *dn)
297 {
298 	struct slot *slot;
299 	int retval = 0;
300 	int i;
301 	const int *indexes, *names, *types, *power_domains;
302 	char *name, *type;
303 
304 	if (!dn->name || strcmp(dn->name, "pci"))
305 		return 0;
306 
307 	/* If this is not a hotplug slot, return without doing anything. */
308 	if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
309 		return 0;
310 
311 	dbg("Entry %s: dn->full_name=%s\n", __FUNCTION__, dn->full_name);
312 
313 	/* register PCI devices */
314 	name = (char *) &names[1];
315 	type = (char *) &types[1];
316 	for (i = 0; i < indexes[0]; i++) {
317 
318 		slot = alloc_slot_struct(dn, indexes[i + 1], name, power_domains[i + 1]);
319 		if (!slot)
320 			return -ENOMEM;
321 
322 		slot->type = simple_strtoul(type, NULL, 10);
323 
324 		dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
325 				indexes[i + 1], name, type);
326 
327 		retval = rpaphp_enable_slot(slot);
328 		if (!retval)
329 			retval = rpaphp_register_slot(slot);
330 
331 		if (retval)
332 			dealloc_slot_struct(slot);
333 
334 		name += strlen(name) + 1;
335 		type += strlen(type) + 1;
336 	}
337 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
338 
339 	/* XXX FIXME: reports a failure only if last entry in loop failed */
340 	return retval;
341 }
342 
343 static void __exit cleanup_slots(void)
344 {
345 	struct list_head *tmp, *n;
346 	struct slot *slot;
347 
348 	/*
349 	 * Unregister all of our slots with the pci_hotplug subsystem,
350 	 * and free up all memory that we had allocated.
351 	 * memory will be freed in release_slot callback.
352 	 */
353 
354 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
355 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
356 		list_del(&slot->rpaphp_slot_list);
357 		pci_hp_deregister(slot->hotplug_slot);
358 	}
359 	return;
360 }
361 
362 static int __init rpaphp_init(void)
363 {
364 	struct device_node *dn = NULL;
365 
366 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
367 
368 	while ((dn = of_find_node_by_name(dn, "pci")))
369 		rpaphp_add_slot(dn);
370 
371 	return 0;
372 }
373 
374 static void __exit rpaphp_exit(void)
375 {
376 	cleanup_slots();
377 }
378 
379 static int enable_slot(struct hotplug_slot *hotplug_slot)
380 {
381 	struct slot *slot = (struct slot *)hotplug_slot->private;
382 	int state;
383 	int retval;
384 
385 	if (slot->state == CONFIGURED)
386 		return 0;
387 
388 	retval = rpaphp_get_sensor_state(slot, &state);
389 	if (retval)
390 		return retval;
391 
392 	if (state == PRESENT) {
393 		pcibios_add_pci_devices(slot->bus);
394 		slot->state = CONFIGURED;
395 	} else if (state == EMPTY) {
396 		slot->state = EMPTY;
397 	} else {
398 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__, slot->name);
399 		slot->state = NOT_VALID;
400 		return -EINVAL;
401 	}
402 	return 0;
403 }
404 
405 static int disable_slot(struct hotplug_slot *hotplug_slot)
406 {
407 	struct slot *slot = (struct slot *)hotplug_slot->private;
408 	if (slot->state == NOT_CONFIGURED)
409 		return -EINVAL;
410 
411 	pcibios_remove_pci_devices(slot->bus);
412 	slot->state = NOT_CONFIGURED;
413 	return 0;
414 }
415 
416 struct hotplug_slot_ops rpaphp_hotplug_slot_ops = {
417 	.owner = THIS_MODULE,
418 	.enable_slot = enable_slot,
419 	.disable_slot = disable_slot,
420 	.set_attention_status = set_attention_status,
421 	.get_power_status = get_power_status,
422 	.get_attention_status = get_attention_status,
423 	.get_adapter_status = get_adapter_status,
424 	.get_max_bus_speed = get_max_bus_speed,
425 };
426 
427 module_init(rpaphp_init);
428 module_exit(rpaphp_exit);
429 
430 EXPORT_SYMBOL_GPL(rpaphp_add_slot);
431 EXPORT_SYMBOL_GPL(rpaphp_slot_head);
432 EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
433