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 <linux/vmalloc.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 bool rpaphp_debug;
41 LIST_HEAD(rpaphp_slot_head);
42 EXPORT_SYMBOL_GPL(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_named(debug, rpaphp_debug, bool, 0644);
55 
56 /**
57  * set_attention_status - set attention LED
58  * @hotplug_slot: target &hotplug_slot
59  * @value: LED control value
60  *
61  * echo 0 > attention -- set LED OFF
62  * echo 1 > attention -- set LED ON
63  * echo 2 > attention -- set LED ID(identify, light is blinking)
64  */
65 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 value)
66 {
67 	int rc;
68 	struct slot *slot = (struct slot *)hotplug_slot->private;
69 
70 	switch (value) {
71 	case 0:
72 	case 1:
73 	case 2:
74 		break;
75 	default:
76 		value = 1;
77 		break;
78 	}
79 
80 	rc = rtas_set_indicator(DR_INDICATOR, slot->index, value);
81 	if (!rc)
82 		hotplug_slot->info->attention_status = value;
83 
84 	return rc;
85 }
86 
87 /**
88  * get_power_status - get power status of a slot
89  * @hotplug_slot: slot to get status
90  * @value: pointer to store status
91  */
92 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
93 {
94 	int retval, level;
95 	struct slot *slot = (struct slot *)hotplug_slot->private;
96 
97 	retval = rtas_get_power_level (slot->power_domain, &level);
98 	if (!retval)
99 		*value = level;
100 	return retval;
101 }
102 
103 /**
104  * get_attention_status - get attention LED status
105  * @hotplug_slot: slot to get status
106  * @value: pointer to store status
107  */
108 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
109 {
110 	struct slot *slot = (struct slot *)hotplug_slot->private;
111 	*value = slot->hotplug_slot->info->attention_status;
112 	return 0;
113 }
114 
115 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
116 {
117 	struct slot *slot = (struct slot *)hotplug_slot->private;
118 	int rc, state;
119 
120 	rc = rpaphp_get_sensor_state(slot, &state);
121 
122 	*value = NOT_VALID;
123 	if (rc)
124 		return rc;
125 
126 	if (state == EMPTY)
127 		*value = EMPTY;
128 	else if (state == PRESENT)
129 		*value = slot->state;
130 
131 	return 0;
132 }
133 
134 static enum pci_bus_speed get_max_bus_speed(struct slot *slot)
135 {
136 	enum pci_bus_speed speed;
137 	switch (slot->type) {
138 	case 1:
139 	case 2:
140 	case 3:
141 	case 4:
142 	case 5:
143 	case 6:
144 		speed = PCI_SPEED_33MHz;	/* speed for case 1-6 */
145 		break;
146 	case 7:
147 	case 8:
148 		speed = PCI_SPEED_66MHz;
149 		break;
150 	case 11:
151 	case 14:
152 		speed = PCI_SPEED_66MHz_PCIX;
153 		break;
154 	case 12:
155 	case 15:
156 		speed = PCI_SPEED_100MHz_PCIX;
157 		break;
158 	case 13:
159 	case 16:
160 		speed = PCI_SPEED_133MHz_PCIX;
161 		break;
162 	default:
163 		speed = PCI_SPEED_UNKNOWN;
164 		break;
165 	}
166 
167 	return speed;
168 }
169 
170 static int get_children_props(struct device_node *dn, const int **drc_indexes,
171 		const int **drc_names, const int **drc_types,
172 		const int **drc_power_domains)
173 {
174 	const int *indexes, *names, *types, *domains;
175 
176 	indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
177 	names = of_get_property(dn, "ibm,drc-names", NULL);
178 	types = of_get_property(dn, "ibm,drc-types", NULL);
179 	domains = of_get_property(dn, "ibm,drc-power-domains", NULL);
180 
181 	if (!indexes || !names || !types || !domains) {
182 		/* Slot does not have dynamically-removable children */
183 		return -EINVAL;
184 	}
185 	if (drc_indexes)
186 		*drc_indexes = indexes;
187 	if (drc_names)
188 		/* &drc_names[1] contains NULL terminated slot names */
189 		*drc_names = names;
190 	if (drc_types)
191 		/* &drc_types[1] contains NULL terminated slot types */
192 		*drc_types = types;
193 	if (drc_power_domains)
194 		*drc_power_domains = domains;
195 
196 	return 0;
197 }
198 
199 /* To get the DRC props describing the current node, first obtain it's
200  * my-drc-index property.  Next obtain the DRC list from it's parent.  Use
201  * the my-drc-index for correlation, and obtain the requested properties.
202  */
203 int rpaphp_get_drc_props(struct device_node *dn, int *drc_index,
204 		char **drc_name, char **drc_type, int *drc_power_domain)
205 {
206 	const int *indexes, *names;
207 	const int *types, *domains;
208 	const unsigned int *my_index;
209 	char *name_tmp, *type_tmp;
210 	int i, rc;
211 
212 	my_index = of_get_property(dn, "ibm,my-drc-index", NULL);
213 	if (!my_index) {
214 		/* Node isn't DLPAR/hotplug capable */
215 		return -EINVAL;
216 	}
217 
218 	rc = get_children_props(dn->parent, &indexes, &names, &types, &domains);
219 	if (rc < 0) {
220 		return -EINVAL;
221 	}
222 
223 	name_tmp = (char *) &names[1];
224 	type_tmp = (char *) &types[1];
225 
226 	/* Iterate through parent properties, looking for my-drc-index */
227 	for (i = 0; i < be32_to_cpu(indexes[0]); i++) {
228 		if ((unsigned int) indexes[i + 1] == *my_index) {
229 			if (drc_name)
230 				*drc_name = name_tmp;
231 			if (drc_type)
232 				*drc_type = type_tmp;
233 			if (drc_index)
234 				*drc_index = be32_to_cpu(*my_index);
235 			if (drc_power_domain)
236 				*drc_power_domain = be32_to_cpu(domains[i+1]);
237 			return 0;
238 		}
239 		name_tmp += (strlen(name_tmp) + 1);
240 		type_tmp += (strlen(type_tmp) + 1);
241 	}
242 
243 	return -EINVAL;
244 }
245 EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
246 
247 static int is_php_type(char *drc_type)
248 {
249 	unsigned long value;
250 	char *endptr;
251 
252 	/* PCI Hotplug nodes have an integer for drc_type */
253 	value = simple_strtoul(drc_type, &endptr, 10);
254 	if (endptr == drc_type)
255 		return 0;
256 
257 	return 1;
258 }
259 
260 /**
261  * is_php_dn() - return 1 if this is a hotpluggable pci slot, else 0
262  * @dn: target &device_node
263  * @indexes: passed to get_children_props()
264  * @names: passed to get_children_props()
265  * @types: returned from get_children_props()
266  * @power_domains:
267  *
268  * This routine will return true only if the device node is
269  * a hotpluggable slot. This routine will return false
270  * for built-in pci slots (even when the built-in slots are
271  * dlparable.)
272  */
273 static int is_php_dn(struct device_node *dn, const int **indexes,
274 		const int **names, const int **types, const int **power_domains)
275 {
276 	const int *drc_types;
277 	int rc;
278 
279 	rc = get_children_props(dn, indexes, names, &drc_types, power_domains);
280 	if (rc < 0)
281 		return 0;
282 
283 	if (!is_php_type((char *) &drc_types[1]))
284 		return 0;
285 
286 	*types = drc_types;
287 	return 1;
288 }
289 
290 /**
291  * rpaphp_add_slot -- declare a hotplug slot to the hotplug subsystem.
292  * @dn: device node of slot
293  *
294  * This subroutine will register a hotpluggable slot with the
295  * PCI hotplug infrastructure. This routine is typically called
296  * during boot time, if the hotplug slots are present at boot time,
297  * or is called later, by the dlpar add code, if the slot is
298  * being dynamically added during runtime.
299  *
300  * If the device node points at an embedded (built-in) slot, this
301  * routine will just return without doing anything, since embedded
302  * slots cannot be hotplugged.
303  *
304  * To remove a slot, it suffices to call rpaphp_deregister_slot().
305  */
306 int rpaphp_add_slot(struct device_node *dn)
307 {
308 	struct slot *slot;
309 	int retval = 0;
310 	int i;
311 	const int *indexes, *names, *types, *power_domains;
312 	char *name, *type;
313 
314 	if (!dn->name || strcmp(dn->name, "pci"))
315 		return 0;
316 
317 	/* If this is not a hotplug slot, return without doing anything. */
318 	if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
319 		return 0;
320 
321 	dbg("Entry %s: dn->full_name=%s\n", __func__, dn->full_name);
322 
323 	/* register PCI devices */
324 	name = (char *) &names[1];
325 	type = (char *) &types[1];
326 	for (i = 0; i < be32_to_cpu(indexes[0]); i++) {
327 		int index;
328 
329 		index = be32_to_cpu(indexes[i + 1]);
330 		slot = alloc_slot_struct(dn, index, name,
331 					 be32_to_cpu(power_domains[i + 1]));
332 		if (!slot)
333 			return -ENOMEM;
334 
335 		slot->type = simple_strtoul(type, NULL, 10);
336 
337 		dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
338 				index, name, type);
339 
340 		retval = rpaphp_enable_slot(slot);
341 		if (!retval)
342 			retval = rpaphp_register_slot(slot);
343 
344 		if (retval)
345 			dealloc_slot_struct(slot);
346 
347 		name += strlen(name) + 1;
348 		type += strlen(type) + 1;
349 	}
350 	dbg("%s - Exit: rc[%d]\n", __func__, retval);
351 
352 	/* XXX FIXME: reports a failure only if last entry in loop failed */
353 	return retval;
354 }
355 EXPORT_SYMBOL_GPL(rpaphp_add_slot);
356 
357 static void __exit cleanup_slots(void)
358 {
359 	struct list_head *tmp, *n;
360 	struct slot *slot;
361 
362 	/*
363 	 * Unregister all of our slots with the pci_hotplug subsystem,
364 	 * and free up all memory that we had allocated.
365 	 * memory will be freed in release_slot callback.
366 	 */
367 
368 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
369 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
370 		list_del(&slot->rpaphp_slot_list);
371 		pci_hp_deregister(slot->hotplug_slot);
372 	}
373 	return;
374 }
375 
376 static int __init rpaphp_init(void)
377 {
378 	struct device_node *dn = NULL;
379 
380 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
381 
382 	while ((dn = of_find_node_by_name(dn, "pci")))
383 		rpaphp_add_slot(dn);
384 
385 	return 0;
386 }
387 
388 static void __exit rpaphp_exit(void)
389 {
390 	cleanup_slots();
391 }
392 
393 static int enable_slot(struct hotplug_slot *hotplug_slot)
394 {
395 	struct slot *slot = (struct slot *)hotplug_slot->private;
396 	int state;
397 	int retval;
398 
399 	if (slot->state == CONFIGURED)
400 		return 0;
401 
402 	retval = rpaphp_get_sensor_state(slot, &state);
403 	if (retval)
404 		return retval;
405 
406 	if (state == PRESENT) {
407 		pci_lock_rescan_remove();
408 		pcibios_add_pci_devices(slot->bus);
409 		pci_unlock_rescan_remove();
410 		slot->state = CONFIGURED;
411 	} else if (state == EMPTY) {
412 		slot->state = EMPTY;
413 	} else {
414 		err("%s: slot[%s] is in invalid state\n", __func__, slot->name);
415 		slot->state = NOT_VALID;
416 		return -EINVAL;
417 	}
418 
419 	slot->bus->max_bus_speed = get_max_bus_speed(slot);
420 	return 0;
421 }
422 
423 static int disable_slot(struct hotplug_slot *hotplug_slot)
424 {
425 	struct slot *slot = (struct slot *)hotplug_slot->private;
426 	if (slot->state == NOT_CONFIGURED)
427 		return -EINVAL;
428 
429 	pci_lock_rescan_remove();
430 	pcibios_remove_pci_devices(slot->bus);
431 	pci_unlock_rescan_remove();
432 	vm_unmap_aliases();
433 
434 	slot->state = NOT_CONFIGURED;
435 	return 0;
436 }
437 
438 struct hotplug_slot_ops rpaphp_hotplug_slot_ops = {
439 	.enable_slot = enable_slot,
440 	.disable_slot = disable_slot,
441 	.set_attention_status = set_attention_status,
442 	.get_power_status = get_power_status,
443 	.get_attention_status = get_attention_status,
444 	.get_adapter_status = get_adapter_status,
445 };
446 
447 module_init(rpaphp_init);
448 module_exit(rpaphp_exit);
449