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/config.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/moduleparam.h>
29 #include <linux/pci.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 #include "pci_hotplug.h"
41 
42 int debug;
43 static struct semaphore rpaphp_sem;
44 LIST_HEAD(rpaphp_slot_head);
45 int num_slots;
46 
47 #define DRIVER_VERSION	"0.1"
48 #define DRIVER_AUTHOR	"Linda Xie <lxie@us.ibm.com>"
49 #define DRIVER_DESC	"RPA HOT Plug PCI Controller Driver"
50 
51 #define MAX_LOC_CODE 128
52 
53 MODULE_AUTHOR(DRIVER_AUTHOR);
54 MODULE_DESCRIPTION(DRIVER_DESC);
55 MODULE_LICENSE("GPL");
56 
57 module_param(debug, bool, 0644);
58 
59 static int enable_slot(struct hotplug_slot *slot);
60 static int disable_slot(struct hotplug_slot *slot);
61 static int set_attention_status(struct hotplug_slot *slot, u8 value);
62 static int get_power_status(struct hotplug_slot *slot, u8 * value);
63 static int get_attention_status(struct hotplug_slot *slot, u8 * value);
64 static int get_adapter_status(struct hotplug_slot *slot, u8 * value);
65 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value);
66 
67 struct hotplug_slot_ops rpaphp_hotplug_slot_ops = {
68 	.owner = THIS_MODULE,
69 	.enable_slot = enable_slot,
70 	.disable_slot = disable_slot,
71 	.set_attention_status = set_attention_status,
72 	.get_power_status = get_power_status,
73 	.get_attention_status = get_attention_status,
74 	.get_adapter_status = get_adapter_status,
75 	.get_max_bus_speed = get_max_bus_speed,
76 };
77 
78 static int rpaphp_get_attention_status(struct slot *slot)
79 {
80 	return slot->hotplug_slot->info->attention_status;
81 }
82 
83 /**
84  * set_attention_status - set attention LED
85  * echo 0 > attention -- set LED OFF
86  * echo 1 > attention -- set LED ON
87  * echo 2 > attention -- set LED ID(identify, light is blinking)
88  *
89  */
90 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 value)
91 {
92 	int retval = 0;
93 	struct slot *slot = (struct slot *)hotplug_slot->private;
94 
95 	down(&rpaphp_sem);
96 	switch (value) {
97 	case 0:
98 		retval = rpaphp_set_attention_status(slot, LED_OFF);
99 		hotplug_slot->info->attention_status = 0;
100 		break;
101 	case 1:
102 	default:
103 		retval = rpaphp_set_attention_status(slot, LED_ON);
104 		hotplug_slot->info->attention_status = 1;
105 		break;
106 	case 2:
107 		retval = rpaphp_set_attention_status(slot, LED_ID);
108 		hotplug_slot->info->attention_status = 2;
109 		break;
110 	}
111 	up(&rpaphp_sem);
112 	return retval;
113 }
114 
115 /**
116  * get_power_status - get power status of a slot
117  * @hotplug_slot: slot to get status
118  * @value: pointer to store status
119  *
120  *
121  */
122 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
123 {
124 	int retval;
125 	struct slot *slot = (struct slot *)hotplug_slot->private;
126 
127 	down(&rpaphp_sem);
128 	retval = rpaphp_get_power_status(slot, value);
129 	up(&rpaphp_sem);
130 	return retval;
131 }
132 
133 /**
134  * get_attention_status - get attention LED status
135  *
136  *
137  */
138 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
139 {
140 	int retval = 0;
141 	struct slot *slot = (struct slot *)hotplug_slot->private;
142 
143 	down(&rpaphp_sem);
144 	*value = rpaphp_get_attention_status(slot);
145 	up(&rpaphp_sem);
146 	return retval;
147 }
148 
149 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
150 {
151 	struct slot *slot = (struct slot *)hotplug_slot->private;
152 	int retval = 0;
153 
154 	down(&rpaphp_sem);
155 	retval = rpaphp_get_pci_adapter_status(slot, 0, value);
156 	up(&rpaphp_sem);
157 	return retval;
158 }
159 
160 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
161 {
162 	struct slot *slot = (struct slot *)hotplug_slot->private;
163 
164 	down(&rpaphp_sem);
165 	switch (slot->type) {
166 	case 1:
167 	case 2:
168 	case 3:
169 	case 4:
170 	case 5:
171 	case 6:
172 		*value = PCI_SPEED_33MHz;	/* speed for case 1-6 */
173 		break;
174 	case 7:
175 	case 8:
176 		*value = PCI_SPEED_66MHz;
177 		break;
178 	case 11:
179 	case 14:
180 		*value = PCI_SPEED_66MHz_PCIX;
181 		break;
182 	case 12:
183 	case 15:
184 		*value = PCI_SPEED_100MHz_PCIX;
185 		break;
186 	case 13:
187 	case 16:
188 		*value = PCI_SPEED_133MHz_PCIX;
189 		break;
190 	default:
191 		*value = PCI_SPEED_UNKNOWN;
192 		break;
193 
194 	}
195 	up(&rpaphp_sem);
196 	return 0;
197 }
198 
199 int rpaphp_remove_slot(struct slot *slot)
200 {
201 	return deregister_slot(slot);
202 }
203 
204 static int get_children_props(struct device_node *dn, int **drc_indexes,
205 		int **drc_names, int **drc_types, int **drc_power_domains)
206 {
207 	int *indexes, *names;
208 	int *types, *domains;
209 
210 	indexes = (int *) get_property(dn, "ibm,drc-indexes", NULL);
211 	names = (int *) get_property(dn, "ibm,drc-names", NULL);
212 	types = (int *) get_property(dn, "ibm,drc-types", NULL);
213 	domains = (int *) get_property(dn, "ibm,drc-power-domains", NULL);
214 
215 	if (!indexes || !names || !types || !domains) {
216 		/* Slot does not have dynamically-removable children */
217 		return -EINVAL;
218 	}
219 	if (drc_indexes)
220 		*drc_indexes = indexes;
221 	if (drc_names)
222 		/* &drc_names[1] contains NULL terminated slot names */
223 		*drc_names = names;
224 	if (drc_types)
225 		/* &drc_types[1] contains NULL terminated slot types */
226 		*drc_types = types;
227 	if (drc_power_domains)
228 		*drc_power_domains = domains;
229 
230 	return 0;
231 }
232 
233 /* To get the DRC props describing the current node, first obtain it's
234  * my-drc-index property.  Next obtain the DRC list from it's parent.  Use
235  * the my-drc-index for correlation, and obtain the requested properties.
236  */
237 int rpaphp_get_drc_props(struct device_node *dn, int *drc_index,
238 		char **drc_name, char **drc_type, int *drc_power_domain)
239 {
240 	int *indexes, *names;
241 	int *types, *domains;
242 	unsigned int *my_index;
243 	char *name_tmp, *type_tmp;
244 	int i, rc;
245 
246 	my_index = (int *) get_property(dn, "ibm,my-drc-index", NULL);
247 	if (!my_index) {
248 		/* Node isn't DLPAR/hotplug capable */
249 		return -EINVAL;
250 	}
251 
252 	rc = get_children_props(dn->parent, &indexes, &names, &types, &domains);
253 	if (rc < 0) {
254 		return -EINVAL;
255 	}
256 
257 	name_tmp = (char *) &names[1];
258 	type_tmp = (char *) &types[1];
259 
260 	/* Iterate through parent properties, looking for my-drc-index */
261 	for (i = 0; i < indexes[0]; i++) {
262 		if ((unsigned int) indexes[i + 1] == *my_index) {
263 			if (drc_name)
264                 		*drc_name = name_tmp;
265 			if (drc_type)
266 				*drc_type = type_tmp;
267 			if (drc_index)
268 				*drc_index = *my_index;
269 			if (drc_power_domain)
270 				*drc_power_domain = domains[i+1];
271 			return 0;
272 		}
273 		name_tmp += (strlen(name_tmp) + 1);
274 		type_tmp += (strlen(type_tmp) + 1);
275 	}
276 
277 	return -EINVAL;
278 }
279 
280 static int is_php_type(char *drc_type)
281 {
282 	unsigned long value;
283 	char *endptr;
284 
285 	/* PCI Hotplug nodes have an integer for drc_type */
286 	value = simple_strtoul(drc_type, &endptr, 10);
287 	if (endptr == drc_type)
288 		return 0;
289 
290 	return 1;
291 }
292 
293 static int is_php_dn(struct device_node *dn, int **indexes, int **names,
294 		int **types, int **power_domains)
295 {
296 	int *drc_types;
297 	int rc;
298 
299 	rc = get_children_props(dn, indexes, names, &drc_types, power_domains);
300 	if (rc >= 0) {
301 		if (is_php_type((char *) &drc_types[1])) {
302 			*types = drc_types;
303 			return 1;
304 		}
305 	}
306 
307 	return 0;
308 }
309 
310 /****************************************************************
311  *	rpaphp not only registers PCI hotplug slots(HOTPLUG),
312  *	but also logical DR slots(EMBEDDED).
313  *	HOTPLUG slot: An adapter can be physically added/removed.
314  *	EMBEDDED slot: An adapter can be logically removed/added
315  *		  from/to a partition with the slot.
316  ***************************************************************/
317 int rpaphp_add_slot(struct device_node *dn)
318 {
319 	struct slot *slot;
320 	int retval = 0;
321 	int i;
322 	int *indexes, *names, *types, *power_domains;
323 	char *name, *type;
324 
325 	dbg("Entry %s: dn->full_name=%s\n", __FUNCTION__, dn->full_name);
326 
327 	/* register PCI devices */
328 	if (dn->name != 0 && strcmp(dn->name, "pci") == 0) {
329 		if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
330 			goto exit;
331 
332 		name = (char *) &names[1];
333 		type = (char *) &types[1];
334 		for (i = 0; i < indexes[0]; i++,
335 	     		name += (strlen(name) + 1), type += (strlen(type) + 1)) 		{
336 
337 			if (!(slot = alloc_slot_struct(dn, indexes[i + 1], name,
338 				       power_domains[i + 1]))) {
339 				retval = -ENOMEM;
340 				goto exit;
341 			}
342 			slot->type = simple_strtoul(type, NULL, 10);
343 
344 			dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
345 					indexes[i + 1], name, type);
346 
347 			retval = register_pci_slot(slot);
348 		}
349 	}
350 exit:
351 	dbg("%s - Exit: num_slots=%d rc[%d]\n",
352 	    __FUNCTION__, num_slots, retval);
353 	return retval;
354 }
355 
356 static void __exit cleanup_slots(void)
357 {
358 	struct list_head *tmp, *n;
359 	struct slot *slot;
360 
361 	/*
362 	 * Unregister all of our slots with the pci_hotplug subsystem,
363 	 * and free up all memory that we had allocated.
364 	 * memory will be freed in release_slot callback.
365 	 */
366 
367 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
368 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
369 		list_del(&slot->rpaphp_slot_list);
370 		pci_hp_deregister(slot->hotplug_slot);
371 	}
372 	return;
373 }
374 
375 static int __init rpaphp_init(void)
376 {
377 	struct device_node *dn = NULL;
378 
379 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
380 	init_MUTEX(&rpaphp_sem);
381 
382 	while ((dn = of_find_node_by_type(dn, "pci")))
383 		rpaphp_add_slot(dn);
384 
385 	if (!num_slots)
386 		return -ENODEV;
387 
388 	return 0;
389 }
390 
391 static void __exit rpaphp_exit(void)
392 {
393 	cleanup_slots();
394 }
395 
396 static int enable_slot(struct hotplug_slot *hotplug_slot)
397 {
398 	int retval = 0;
399 	struct slot *slot = (struct slot *)hotplug_slot->private;
400 
401 	if (slot->state == CONFIGURED) {
402 		dbg("%s: %s is already enabled\n", __FUNCTION__, slot->name);
403 		goto exit;
404 	}
405 
406 	dbg("ENABLING SLOT %s\n", slot->name);
407 	down(&rpaphp_sem);
408 	retval = rpaphp_enable_pci_slot(slot);
409 	up(&rpaphp_sem);
410 exit:
411 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
412 	return retval;
413 }
414 
415 static int disable_slot(struct hotplug_slot *hotplug_slot)
416 {
417 	int retval = -EINVAL;
418 	struct slot *slot = (struct slot *)hotplug_slot->private;
419 
420 	dbg("%s - Entry: slot[%s]\n", __FUNCTION__, slot->name);
421 
422 	if (slot->state == NOT_CONFIGURED) {
423 		dbg("%s: %s is already disabled\n", __FUNCTION__, slot->name);
424 		goto exit;
425 	}
426 
427 	dbg("DISABLING SLOT %s\n", slot->name);
428 	down(&rpaphp_sem);
429 	retval = rpaphp_unconfig_pci_adapter(slot->bus);
430 	up(&rpaphp_sem);
431 	slot->state = NOT_CONFIGURED;
432 	info("%s: devices in slot[%s] unconfigured.\n", __FUNCTION__,
433 	     slot->name);
434 exit:
435 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
436 	return retval;
437 }
438 
439 module_init(rpaphp_init);
440 module_exit(rpaphp_exit);
441 
442 EXPORT_SYMBOL_GPL(rpaphp_add_slot);
443 EXPORT_SYMBOL_GPL(rpaphp_remove_slot);
444 EXPORT_SYMBOL_GPL(rpaphp_slot_head);
445 EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
446