xref: /openbmc/linux/drivers/pci/hotplug/pciehp_pci.c (revision 05bcf503)
1 /*
2  * PCI Express Hot Plug Controller Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  * Copyright (C) 2003-2004 Intel Corporation
8  *
9  * All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or (at
14  * your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
19  * NON INFRINGEMENT.  See the GNU General Public License for more
20  * details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
27  *
28  */
29 
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/types.h>
33 #include <linux/pci.h>
34 #include "../pci.h"
35 #include "pciehp.h"
36 
37 int pciehp_configure_device(struct slot *p_slot)
38 {
39 	struct pci_dev *dev;
40 	struct pci_dev *bridge = p_slot->ctrl->pcie->port;
41 	struct pci_bus *parent = bridge->subordinate;
42 	int num, fn;
43 	struct controller *ctrl = p_slot->ctrl;
44 
45 	dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
46 	if (dev) {
47 		ctrl_err(ctrl, "Device %s already exists "
48 			 "at %04x:%02x:00, cannot hot-add\n", pci_name(dev),
49 			 pci_domain_nr(parent), parent->number);
50 		pci_dev_put(dev);
51 		return -EINVAL;
52 	}
53 
54 	num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
55 	if (num == 0) {
56 		ctrl_err(ctrl, "No new device found\n");
57 		return -ENODEV;
58 	}
59 
60 	for (fn = 0; fn < 8; fn++) {
61 		dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
62 		if (!dev)
63 			continue;
64 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
65 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
66 			pci_hp_add_bridge(dev);
67 		pci_dev_put(dev);
68 	}
69 
70 	pci_assign_unassigned_bridge_resources(bridge);
71 
72 	for (fn = 0; fn < 8; fn++) {
73 		dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
74 		if (!dev)
75 			continue;
76 		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
77 			pci_dev_put(dev);
78 			continue;
79 		}
80 		pci_configure_slot(dev);
81 		pci_dev_put(dev);
82 	}
83 
84 	pci_bus_add_devices(parent);
85 
86 	return 0;
87 }
88 
89 int pciehp_unconfigure_device(struct slot *p_slot)
90 {
91 	int ret, rc = 0;
92 	int j;
93 	u8 bctl = 0;
94 	u8 presence = 0;
95 	struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
96 	u16 command;
97 	struct controller *ctrl = p_slot->ctrl;
98 
99 	ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
100 		 __func__, pci_domain_nr(parent), parent->number);
101 	ret = pciehp_get_adapter_status(p_slot, &presence);
102 	if (ret)
103 		presence = 0;
104 
105 	for (j = 0; j < 8; j++) {
106 		struct pci_dev *temp = pci_get_slot(parent, PCI_DEVFN(0, j));
107 		if (!temp)
108 			continue;
109 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
110 			pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
111 			if (bctl & PCI_BRIDGE_CTL_VGA) {
112 				ctrl_err(ctrl,
113 					 "Cannot remove display device %s\n",
114 					 pci_name(temp));
115 				pci_dev_put(temp);
116 				rc = -EINVAL;
117 				break;
118 			}
119 		}
120 		pci_stop_and_remove_bus_device(temp);
121 		/*
122 		 * Ensure that no new Requests will be generated from
123 		 * the device.
124 		 */
125 		if (presence) {
126 			pci_read_config_word(temp, PCI_COMMAND, &command);
127 			command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
128 			command |= PCI_COMMAND_INTX_DISABLE;
129 			pci_write_config_word(temp, PCI_COMMAND, command);
130 		}
131 		pci_dev_put(temp);
132 	}
133 
134 	return rc;
135 }
136