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);
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
49MODULE_AUTHOR(DRIVER_AUTHOR);
50MODULE_DESCRIPTION(DRIVER_DESC);
51MODULE_LICENSE("GPL");
52
53module_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 */
64static 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 */
91static 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 */
107static 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
114static 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
133static 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
169static 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 */
202int 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
245static 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 */
271static 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 */
304int 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
351static 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
370static 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
382static void __exit rpaphp_exit(void)
383{
384	cleanup_slots();
385}
386
387static 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
415static 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
428struct 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
437module_init(rpaphp_init);
438module_exit(rpaphp_exit);
439
440EXPORT_SYMBOL_GPL(rpaphp_add_slot);
441EXPORT_SYMBOL_GPL(rpaphp_slot_head);
442EXPORT_SYMBOL_GPL(rpaphp_get_drc_props);
443