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 int rpaphp_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_named(debug, rpaphp_debug, bool, 0644);
54 
55 /**
56  * set_attention_status - set attention LED
57  * @hotplug_slot: target &hotplug_slot
58  * @value: LED control value
59  *
60  * echo 0 > attention -- set LED OFF
61  * echo 1 > attention -- set LED ON
62  * echo 2 > attention -- set LED ID(identify, light is blinking)
63  */
64 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 value)
65 {
66 	int rc;
67 	struct slot *slot = (struct slot *)hotplug_slot->private;
68 
69 	switch (value) {
70 	case 0:
71 	case 1:
72 	case 2:
73 		break;
74 	default:
75 		value = 1;
76 		break;
77 	}
78 
79 	rc = rtas_set_indicator(DR_INDICATOR, slot->index, value);
80 	if (!rc)
81 		hotplug_slot->info->attention_status = value;
82 
83 	return rc;
84 }
85 
86 /**
87  * get_power_status - get power status of a slot
88  * @hotplug_slot: slot to get status
89  * @value: pointer to store status
90  */
91 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 * value)
92 {
93 	int retval, level;
94 	struct slot *slot = (struct slot *)hotplug_slot->private;
95 
96 	retval = rtas_get_power_level (slot->power_domain, &level);
97 	if (!retval)
98 		*value = level;
99 	return retval;
100 }
101 
102 /**
103  * get_attention_status - get attention LED status
104  * @hotplug_slot: slot to get status
105  * @value: pointer to store status
106  */
107 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value)
108 {
109 	struct slot *slot = (struct slot *)hotplug_slot->private;
110 	*value = slot->hotplug_slot->info->attention_status;
111 	return 0;
112 }
113 
114 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value)
115 {
116 	struct slot *slot = (struct slot *)hotplug_slot->private;
117 	int rc, state;
118 
119 	rc = rpaphp_get_sensor_state(slot, &state);
120 
121 	*value = NOT_VALID;
122 	if (rc)
123 		return rc;
124 
125 	if (state == EMPTY)
126 		*value = EMPTY;
127 	else if (state == PRESENT)
128 		*value = slot->state;
129 
130 	return 0;
131 }
132 
133 static enum pci_bus_speed get_max_bus_speed(struct slot *slot)
134 {
135 	enum pci_bus_speed speed;
136 	switch (slot->type) {
137 	case 1:
138 	case 2:
139 	case 3:
140 	case 4:
141 	case 5:
142 	case 6:
143 		speed = PCI_SPEED_33MHz;	/* speed for case 1-6 */
144 		break;
145 	case 7:
146 	case 8:
147 		speed = PCI_SPEED_66MHz;
148 		break;
149 	case 11:
150 	case 14:
151 		speed = PCI_SPEED_66MHz_PCIX;
152 		break;
153 	case 12:
154 	case 15:
155 		speed = PCI_SPEED_100MHz_PCIX;
156 		break;
157 	case 13:
158 	case 16:
159 		speed = PCI_SPEED_133MHz_PCIX;
160 		break;
161 	default:
162 		speed = PCI_SPEED_UNKNOWN;
163 		break;
164 	}
165 
166 	return speed;
167 }
168 
169 static int get_children_props(struct device_node *dn, const int **drc_indexes,
170 		const int **drc_names, const int **drc_types,
171 		const int **drc_power_domains)
172 {
173 	const int *indexes, *names, *types, *domains;
174 
175 	indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
176 	names = of_get_property(dn, "ibm,drc-names", NULL);
177 	types = of_get_property(dn, "ibm,drc-types", NULL);
178 	domains = of_get_property(dn, "ibm,drc-power-domains", NULL);
179 
180 	if (!indexes || !names || !types || !domains) {
181 		/* Slot does not have dynamically-removable children */
182 		return -EINVAL;
183 	}
184 	if (drc_indexes)
185 		*drc_indexes = indexes;
186 	if (drc_names)
187 		/* &drc_names[1] contains NULL terminated slot names */
188 		*drc_names = names;
189 	if (drc_types)
190 		/* &drc_types[1] contains NULL terminated slot types */
191 		*drc_types = types;
192 	if (drc_power_domains)
193 		*drc_power_domains = domains;
194 
195 	return 0;
196 }
197 
198 /* To get the DRC props describing the current node, first obtain it's
199  * my-drc-index property.  Next obtain the DRC list from it's parent.  Use
200  * the my-drc-index for correlation, and obtain the requested properties.
201  */
202 int rpaphp_get_drc_props(struct device_node *dn, int *drc_index,
203 		char **drc_name, char **drc_type, int *drc_power_domain)
204 {
205 	const int *indexes, *names;
206 	const int *types, *domains;
207 	const unsigned int *my_index;
208 	char *name_tmp, *type_tmp;
209 	int i, rc;
210 
211 	my_index = of_get_property(dn, "ibm,my-drc-index", NULL);
212 	if (!my_index) {
213 		/* Node isn't DLPAR/hotplug capable */
214 		return -EINVAL;
215 	}
216 
217 	rc = get_children_props(dn->parent, &indexes, &names, &types, &domains);
218 	if (rc < 0) {
219 		return -EINVAL;
220 	}
221 
222 	name_tmp = (char *) &names[1];
223 	type_tmp = (char *) &types[1];
224 
225 	/* Iterate through parent properties, looking for my-drc-index */
226 	for (i = 0; i < indexes[0]; i++) {
227 		if ((unsigned int) indexes[i + 1] == *my_index) {
228 			if (drc_name)
229                 		*drc_name = name_tmp;
230 			if (drc_type)
231 				*drc_type = type_tmp;
232 			if (drc_index)
233 				*drc_index = *my_index;
234 			if (drc_power_domain)
235 				*drc_power_domain = domains[i+1];
236 			return 0;
237 		}
238 		name_tmp += (strlen(name_tmp) + 1);
239 		type_tmp += (strlen(type_tmp) + 1);
240 	}
241 
242 	return -EINVAL;
243 }
244 
245 static int is_php_type(char *drc_type)
246 {
247 	unsigned long value;
248 	char *endptr;
249 
250 	/* PCI Hotplug nodes have an integer for drc_type */
251 	value = simple_strtoul(drc_type, &endptr, 10);
252 	if (endptr == drc_type)
253 		return 0;
254 
255 	return 1;
256 }
257 
258 /**
259  * is_php_dn() - return 1 if this is a hotpluggable pci slot, else 0
260  * @dn: target &device_node
261  * @indexes: passed to get_children_props()
262  * @names: passed to get_children_props()
263  * @types: returned from get_children_props()
264  * @power_domains:
265  *
266  * This routine will return true only if the device node is
267  * a hotpluggable slot. This routine will return false
268  * for built-in pci slots (even when the built-in slots are
269  * dlparable.)
270  */
271 static int is_php_dn(struct device_node *dn, const int **indexes,
272 		const int **names, const int **types, const int **power_domains)
273 {
274 	const int *drc_types;
275 	int rc;
276 
277 	rc = get_children_props(dn, indexes, names, &drc_types, power_domains);
278 	if (rc < 0)
279 		return 0;
280 
281 	if (!is_php_type((char *) &drc_types[1]))
282 		return 0;
283 
284 	*types = drc_types;
285 	return 1;
286 }
287 
288 /**
289  * rpaphp_add_slot -- declare a hotplug slot to the hotplug subsystem.
290  * @dn: device node of slot
291  *
292  * This subroutine will register a hotplugable slot with the
293  * PCI hotplug infrastructure. This routine is typically called
294  * during boot time, if the hotplug slots are present at boot time,
295  * or is called later, by the dlpar add code, if the slot is
296  * being dynamically added during runtime.
297  *
298  * If the device node points at an embedded (built-in) slot, this
299  * routine will just return without doing anything, since embedded
300  * slots cannot be hotplugged.
301  *
302  * To remove a slot, it suffices to call rpaphp_deregister_slot().
303  */
304 int rpaphp_add_slot(struct device_node *dn)
305 {
306 	struct slot *slot;
307 	int retval = 0;
308 	int i;
309 	const int *indexes, *names, *types, *power_domains;
310 	char *name, *type;
311 
312 	if (!dn->name || strcmp(dn->name, "pci"))
313 		return 0;
314 
315 	/* If this is not a hotplug slot, return without doing anything. */
316 	if (!is_php_dn(dn, &indexes, &names, &types, &power_domains))
317 		return 0;
318 
319 	dbg("Entry %s: dn->full_name=%s\n", __func__, dn->full_name);
320 
321 	/* register PCI devices */
322 	name = (char *) &names[1];
323 	type = (char *) &types[1];
324 	for (i = 0; i < indexes[0]; i++) {
325 
326 		slot = alloc_slot_struct(dn, indexes[i + 1], name, power_domains[i + 1]);
327 		if (!slot)
328 			return -ENOMEM;
329 
330 		slot->type = simple_strtoul(type, NULL, 10);
331 
332 		dbg("Found drc-index:0x%x drc-name:%s drc-type:%s\n",
333 				indexes[i + 1], name, type);
334 
335 		retval = rpaphp_enable_slot(slot);
336 		if (!retval)
337 			retval = rpaphp_register_slot(slot);
338 
339 		if (retval)
340 			dealloc_slot_struct(slot);
341 
342 		name += strlen(name) + 1;
343 		type += strlen(type) + 1;
344 	}
345 	dbg("%s - Exit: rc[%d]\n", __func__, retval);
346 
347 	/* XXX FIXME: reports a failure only if last entry in loop failed */
348 	return retval;
349 }
350 
351 static void __exit cleanup_slots(void)
352 {
353 	struct list_head *tmp, *n;
354 	struct slot *slot;
355 
356 	/*
357 	 * Unregister all of our slots with the pci_hotplug subsystem,
358 	 * and free up all memory that we had allocated.
359 	 * memory will be freed in release_slot callback.
360 	 */
361 
362 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
363 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
364 		list_del(&slot->rpaphp_slot_list);
365 		pci_hp_deregister(slot->hotplug_slot);
366 	}
367 	return;
368 }
369 
370 static int __init rpaphp_init(void)
371 {
372 	struct device_node *dn = NULL;
373 
374 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
375 
376 	while ((dn = of_find_node_by_name(dn, "pci")))
377 		rpaphp_add_slot(dn);
378 
379 	return 0;
380 }
381 
382 static void __exit rpaphp_exit(void)
383 {
384 	cleanup_slots();
385 }
386 
387 static int enable_slot(struct hotplug_slot *hotplug_slot)
388 {
389 	struct slot *slot = (struct slot *)hotplug_slot->private;
390 	int state;
391 	int retval;
392 
393 	if (slot->state == CONFIGURED)
394 		return 0;
395 
396 	retval = rpaphp_get_sensor_state(slot, &state);
397 	if (retval)
398 		return retval;
399 
400 	if (state == PRESENT) {
401 		pcibios_add_pci_devices(slot->bus);
402 		slot->state = CONFIGURED;
403 	} else if (state == EMPTY) {
404 		slot->state = EMPTY;
405 	} else {
406 		err("%s: slot[%s] is in invalid state\n", __func__, slot->name);
407 		slot->state = NOT_VALID;
408 		return -EINVAL;
409 	}
410 
411 	slot->bus->max_bus_speed = get_max_bus_speed(slot);
412 	return 0;
413 }
414 
415 static int disable_slot(struct hotplug_slot *hotplug_slot)
416 {
417 	struct slot *slot = (struct slot *)hotplug_slot->private;
418 	if (slot->state == NOT_CONFIGURED)
419 		return -EINVAL;
420 
421 	pcibios_remove_pci_devices(slot->bus);
422 	vm_unmap_aliases();
423 
424 	slot->state = NOT_CONFIGURED;
425 	return 0;
426 }
427 
428 struct hotplug_slot_ops rpaphp_hotplug_slot_ops = {
429 	.enable_slot = enable_slot,
430 	.disable_slot = disable_slot,
431 	.set_attention_status = set_attention_status,
432 	.get_power_status = get_power_status,
433 	.get_attention_status = get_attention_status,
434 	.get_adapter_status = get_adapter_status,
435 };
436 
437 module_init(rpaphp_init);
438 module_exit(rpaphp_exit);
439 
440 EXPORT_SYMBOL_GPL(rpaphp_add_slot);
441 EXPORT_SYMBOL_GPL(rpaphp_slot_head);
442 EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
443