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
40bool rpaphp_debug;
41LIST_HEAD(rpaphp_slot_head);
42EXPORT_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
50MODULE_AUTHOR(DRIVER_AUTHOR);
51MODULE_DESCRIPTION(DRIVER_DESC);
52MODULE_LICENSE("GPL");
53
54module_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 */
65static 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 */
92static 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 */
108static 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
115static 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
134static 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
170static 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 */
203int 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}
245EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
246
247static 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 */
273static 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 */
306int 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}
355EXPORT_SYMBOL_GPL(rpaphp_add_slot);
356
357static 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
376static int __init rpaphp_init(void)
377{
378	struct device_node *dn;
379
380	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
381
382	for_each_node_by_name(dn, "pci")
383		rpaphp_add_slot(dn);
384
385	return 0;
386}
387
388static void __exit rpaphp_exit(void)
389{
390	cleanup_slots();
391}
392
393static 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
423static 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
438struct 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
447module_init(rpaphp_init);
448module_exit(rpaphp_exit);
449