xref: /openbmc/linux/drivers/pci/hotplug/rpaphp_pci.c (revision 612a462a)
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 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 			    __func__);
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 				    __func__, 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", __func__);
61 		else
62 			err("%s failed to get sensor state\n", __func__);
63 	}
64 	return rc;
65 }
66 
67 /**
68  * rpaphp_enable_slot - record slot state, config pci device
69  * @slot: target &slot
70  *
71  * Initialize values in the slot, and the hotplug_slot info
72  * structures to indicate if there is a pci card plugged into
73  * the slot. If the slot is not empty, run the pcibios routine
74  * to get pcibios stuff correctly set up.
75  */
76 int rpaphp_enable_slot(struct slot *slot)
77 {
78 	int rc, level, state;
79 	struct pci_bus *bus;
80 	struct hotplug_slot_info *info = slot->hotplug_slot->info;
81 
82 	info->adapter_status = NOT_VALID;
83 	slot->state = EMPTY;
84 
85 	/* Find out if the power is turned on for the slot */
86 	rc = rtas_get_power_level(slot->power_domain, &level);
87 	if (rc)
88 		return rc;
89 	info->power_status = level;
90 
91 	/* Figure out if there is an adapter in the slot */
92 	rc = rpaphp_get_sensor_state(slot, &state);
93 	if (rc)
94 		return rc;
95 
96 	bus = pci_find_bus_by_node(slot->dn);
97 	if (!bus) {
98 		err("%s: no pci_bus for dn %pOF\n", __func__, slot->dn);
99 		return -EINVAL;
100 	}
101 
102 	info->adapter_status = EMPTY;
103 	slot->bus = bus;
104 	slot->pci_devs = &bus->devices;
105 
106 	/* if there's an adapter in the slot, go add the pci devices */
107 	if (state == PRESENT) {
108 		info->adapter_status = NOT_CONFIGURED;
109 		slot->state = NOT_CONFIGURED;
110 
111 		/* non-empty slot has to have child */
112 		if (!slot->dn->child) {
113 			err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
114 			    __func__, slot->name);
115 			return -EINVAL;
116 		}
117 
118 		if (list_empty(&bus->devices))
119 			pci_hp_add_devices(bus);
120 
121 		if (!list_empty(&bus->devices)) {
122 			info->adapter_status = CONFIGURED;
123 			slot->state = CONFIGURED;
124 		}
125 
126 		if (rpaphp_debug) {
127 			struct pci_dev *dev;
128 			dbg("%s: pci_devs of slot[%pOF]\n", __func__, slot->dn);
129 			list_for_each_entry(dev, &bus->devices, bus_list)
130 				dbg("\t%s\n", pci_name(dev));
131 		}
132 	}
133 
134 	return 0;
135 }
136