xref: /openbmc/linux/drivers/pci/hotplug/rpaphp_pci.c (revision 8a85a70d)
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/pci.h>
26 #include <linux/string.h>
27 
28 #include <asm/pci-bridge.h>
29 #include <asm/rtas.h>
30 #include <asm/machdep.h>
31 
32 #include "../pci.h"		/* for pci_add_new_bus */
33 #include "rpaphp.h"
34 
35 static int rpaphp_get_sensor_state(struct slot *slot, int *state)
36 {
37 	int rc;
38 	int setlevel;
39 
40 	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
41 
42 	if (rc < 0) {
43 		if (rc == -EFAULT || rc == -EEXIST) {
44 			dbg("%s: slot must be power up to get sensor-state\n",
45 			    __FUNCTION__);
46 
47 			/* some slots have to be powered up
48 			 * before get-sensor will succeed.
49 			 */
50 			rc = rtas_set_power_level(slot->power_domain, POWER_ON,
51 						  &setlevel);
52 			if (rc < 0) {
53 				dbg("%s: power on slot[%s] failed rc=%d.\n",
54 				    __FUNCTION__, slot->name, rc);
55 			} else {
56 				rc = rtas_get_sensor(DR_ENTITY_SENSE,
57 						     slot->index, state);
58 			}
59 		} else if (rc == -ENODEV)
60 			info("%s: slot is unusable\n", __FUNCTION__);
61 		else
62 			err("%s failed to get sensor state\n", __FUNCTION__);
63 	}
64 	return rc;
65 }
66 
67 /**
68  * get_pci_adapter_status - get the status of a slot
69  *
70  * 0-- slot is empty
71  * 1-- adapter is configured
72  * 2-- adapter is not configured
73  * 3-- not valid
74  */
75 int rpaphp_get_pci_adapter_status(struct slot *slot, int is_init, u8 * value)
76 {
77 	struct pci_bus *bus;
78 	int state, rc;
79 
80 	*value = NOT_VALID;
81 	rc = rpaphp_get_sensor_state(slot, &state);
82 	if (rc)
83 		goto exit;
84 
85  	if (state == EMPTY)
86  		*value = EMPTY;
87  	else if (state == PRESENT) {
88 		if (!is_init) {
89 			/* at run-time slot->state can be changed by */
90 			/* config/unconfig adapter */
91 			*value = slot->state;
92 		} else {
93 			bus = pcibios_find_pci_bus(slot->dn);
94 			if (bus && !list_empty(&bus->devices))
95 				*value = CONFIGURED;
96 			else
97 				*value = NOT_CONFIGURED;
98 		}
99 	}
100 exit:
101 	return rc;
102 }
103 
104 static void print_slot_pci_funcs(struct pci_bus *bus)
105 {
106 	struct device_node *dn;
107 	struct pci_dev *dev;
108 
109 	dn = pci_bus_to_OF_node(bus);
110 	if (!dn)
111 		return;
112 
113 	dbg("%s: pci_devs of slot[%s]\n", __FUNCTION__, dn->full_name);
114 	list_for_each_entry (dev, &bus->devices, bus_list)
115 		dbg("\t%s\n", pci_name(dev));
116 	return;
117 }
118 
119 int rpaphp_unconfig_pci_adapter(struct pci_bus *bus)
120 {
121 	struct pci_dev *dev, *tmp;
122 
123 	list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
124 		eeh_remove_bus_device(dev);
125 		pci_remove_bus_device(dev);
126 	}
127 	return 0;
128 }
129 EXPORT_SYMBOL_GPL(rpaphp_unconfig_pci_adapter);
130 
131 static int setup_pci_hotplug_slot_info(struct slot *slot)
132 {
133 	struct hotplug_slot_info *hotplug_slot_info = slot->hotplug_slot->info;
134 
135 	dbg("%s Initilize the PCI slot's hotplug->info structure ...\n",
136 	    __FUNCTION__);
137 	rpaphp_get_power_status(slot, &hotplug_slot_info->power_status);
138 	rpaphp_get_pci_adapter_status(slot, 1,
139 				      &hotplug_slot_info->adapter_status);
140 	if (hotplug_slot_info->adapter_status == NOT_VALID) {
141 		err("%s: NOT_VALID: skip dn->full_name=%s\n",
142 		    __FUNCTION__, slot->dn->full_name);
143 		return -EINVAL;
144 	}
145 	return 0;
146 }
147 
148 static void set_slot_name(struct slot *slot)
149 {
150 	struct pci_bus *bus = slot->bus;
151 	struct pci_dev *bridge;
152 
153 	bridge = bus->self;
154 	if (bridge)
155 		strcpy(slot->name, pci_name(bridge));
156 	else
157 		sprintf(slot->name, "%04x:%02x:00.0", pci_domain_nr(bus),
158 			bus->number);
159 }
160 
161 static int setup_pci_slot(struct slot *slot)
162 {
163 	struct device_node *dn = slot->dn;
164 	struct pci_bus *bus;
165 
166 	BUG_ON(!dn);
167 	bus = pcibios_find_pci_bus(dn);
168 	if (!bus) {
169 		err("%s: no pci_bus for dn %s\n", __FUNCTION__, dn->full_name);
170 		goto exit_rc;
171 	}
172 
173 	slot->bus = bus;
174 	slot->pci_devs = &bus->devices;
175 	set_slot_name(slot);
176 
177 	/* find slot's pci_dev if it's not empty */
178 	if (slot->hotplug_slot->info->adapter_status == EMPTY) {
179 		slot->state = EMPTY;	/* slot is empty */
180 	} else {
181 		/* slot is occupied */
182 		if (!dn->child) {
183 			/* non-empty slot has to have child */
184 			err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
185 				__FUNCTION__, slot->name);
186 			goto exit_rc;
187 		}
188 
189 		if (slot->hotplug_slot->info->adapter_status == NOT_CONFIGURED) {
190 			dbg("%s CONFIGURING pci adapter in slot[%s]\n",
191 				__FUNCTION__, slot->name);
192 			pcibios_add_pci_devices(slot->bus);
193 
194 		} else if (slot->hotplug_slot->info->adapter_status != CONFIGURED) {
195 			err("%s: slot[%s]'s adapter_status is NOT_VALID.\n",
196 				__FUNCTION__, slot->name);
197 			goto exit_rc;
198 		}
199 		print_slot_pci_funcs(slot->bus);
200 		if (!list_empty(slot->pci_devs)) {
201 			slot->state = CONFIGURED;
202 		} else {
203 			/* DLPAR add as opposed to
204 		 	 * boot time */
205 			slot->state = NOT_CONFIGURED;
206 		}
207 	}
208 	return 0;
209 exit_rc:
210 	dealloc_slot_struct(slot);
211 	return -EINVAL;
212 }
213 
214 int register_pci_slot(struct slot *slot)
215 {
216 	int rc = -EINVAL;
217 
218 	if (setup_pci_hotplug_slot_info(slot))
219 		goto exit_rc;
220 	if (setup_pci_slot(slot))
221 		goto exit_rc;
222 	rc = register_slot(slot);
223 exit_rc:
224 	return rc;
225 }
226 
227 int rpaphp_enable_pci_slot(struct slot *slot)
228 {
229 	int retval = 0, state;
230 
231 	retval = rpaphp_get_sensor_state(slot, &state);
232 	if (retval)
233 		goto exit;
234 	dbg("%s: sensor state[%d]\n", __FUNCTION__, state);
235 	/* if slot is not empty, enable the adapter */
236 	if (state == PRESENT) {
237 		dbg("%s : slot[%s] is occupied.\n", __FUNCTION__, slot->name);
238 		pcibios_add_pci_devices(slot->bus);
239 		slot->state = CONFIGURED;
240 		info("%s: devices in slot[%s] configured\n",
241 					__FUNCTION__, slot->name);
242 	} else if (state == EMPTY) {
243 		dbg("%s : slot[%s] is empty\n", __FUNCTION__, slot->name);
244 		slot->state = EMPTY;
245 	} else {
246 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__,
247 		    slot->name);
248 		slot->state = NOT_VALID;
249 		retval = -EINVAL;
250 	}
251 exit:
252 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
253 	return retval;
254 }
255