xref: /linux/drivers/pci/hotplug/pciehp_pci.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
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 static int pciehp_add_bridge(struct pci_dev *dev)
38 {
39 	struct pci_bus *parent = dev->bus;
40 	int pass, busnr, start = parent->secondary;
41 	int end = parent->subordinate;
42 
43 	for (busnr = start; busnr <= end; busnr++) {
44 		if (!pci_find_bus(pci_domain_nr(parent), busnr))
45 			break;
46 	}
47 	if (busnr-- > end) {
48 		err("No bus number available for hot-added bridge %s\n",
49 				pci_name(dev));
50 		return -1;
51 	}
52 	for (pass = 0; pass < 2; pass++)
53 		busnr = pci_scan_bridge(parent, dev, busnr, pass);
54 	if (!dev->subordinate)
55 		return -1;
56 	pci_bus_size_bridges(dev->subordinate);
57 	pci_bus_assign_resources(parent);
58 	pci_enable_bridges(parent);
59 	pci_bus_add_devices(parent);
60 	return 0;
61 }
62 
63 int pciehp_configure_device(struct slot *p_slot)
64 {
65 	struct pci_dev *dev;
66 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
67 	int num, fn;
68 
69 	dev = pci_find_slot(p_slot->bus, PCI_DEVFN(p_slot->device, 0));
70 	if (dev) {
71 		err("Device %s already exists at %x:%x, cannot hot-add\n",
72 				pci_name(dev), p_slot->bus, p_slot->device);
73 		return -EINVAL;
74 	}
75 
76 	num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
77 	if (num == 0) {
78 		err("No new device found\n");
79 		return -ENODEV;
80 	}
81 
82 	for (fn = 0; fn < 8; fn++) {
83 		dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
84 		if (!dev)
85 			continue;
86 		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
87 			err("Cannot hot-add display device %s\n",
88 					pci_name(dev));
89 			continue;
90 		}
91 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
92 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
93 			pciehp_add_bridge(dev);
94 		}
95 		/* TBD: program firmware provided _HPP values */
96 		/* program_fw_provided_values(dev); */
97 	}
98 
99 	pci_bus_assign_resources(parent);
100 	pci_bus_add_devices(parent);
101 	return 0;
102 }
103 
104 int pciehp_unconfigure_device(struct slot *p_slot)
105 {
106 	int rc = 0;
107 	int j;
108 	u8 bctl = 0;
109 
110 	dbg("%s: bus/dev = %x/%x\n", __FUNCTION__, p_slot->bus,
111 				p_slot->device);
112 
113 	for (j=0; j<8 ; j++) {
114 		struct pci_dev* temp = pci_find_slot(p_slot->bus,
115 				(p_slot->device << 3) | j);
116 		if (!temp)
117 			continue;
118 		if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
119 			err("Cannot remove display device %s\n",
120 					pci_name(temp));
121 			continue;
122 		}
123 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
124 			pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
125 			if (bctl & PCI_BRIDGE_CTL_VGA) {
126 				err("Cannot remove display device %s\n",
127 						pci_name(temp));
128 				continue;
129 			}
130 		}
131 		pci_remove_bus_device(temp);
132 	}
133 	/*
134 	 * Some PCI Express root ports require fixup after hot-plug operation.
135 	 */
136 	if (pcie_mch_quirk)
137 		pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
138 
139 	return rc;
140 }
141 
142