xref: /linux/drivers/pci/hotplug/pciehp_pci.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
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 
38 int pciehp_configure_device(struct slot *p_slot)
39 {
40 	struct pci_dev *dev;
41 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
42 	int num, fn;
43 
44 	dev = pci_find_slot(p_slot->bus, PCI_DEVFN(p_slot->device, 0));
45 	if (dev) {
46 		err("Device %s already exists at %x:%x, cannot hot-add\n",
47 				pci_name(dev), p_slot->bus, p_slot->device);
48 		return -EINVAL;
49 	}
50 
51 	num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
52 	if (num == 0) {
53 		err("No new device found\n");
54 		return -ENODEV;
55 	}
56 
57 	for (fn = 0; fn < 8; fn++) {
58 		if (!(dev = pci_find_slot(p_slot->bus,
59 					PCI_DEVFN(p_slot->device, fn))))
60 			continue;
61 		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
62 			err("Cannot hot-add display device %s\n",
63 					pci_name(dev));
64 			continue;
65 		}
66 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
67 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
68 			/* Find an unused bus number for the new bridge */
69 			struct pci_bus *child;
70 			unsigned char busnr, start = parent->secondary;
71 			unsigned char end = parent->subordinate;
72 			for (busnr = start; busnr <= end; busnr++) {
73 				if (!pci_find_bus(pci_domain_nr(parent),
74 							busnr))
75 					break;
76 			}
77 			if (busnr >= end) {
78 				err("No free bus for hot-added bridge\n");
79 				continue;
80 			}
81 			child = pci_add_new_bus(parent, dev, busnr);
82 			if (!child) {
83 				err("Cannot add new bus for %s\n",
84 						pci_name(dev));
85 				continue;
86 			}
87 			child->subordinate = pci_do_scan_bus(child);
88 			pci_bus_size_bridges(child);
89 		}
90 		/* TBD: program firmware provided _HPP values */
91 		/* program_fw_provided_values(dev); */
92 	}
93 
94 	pci_bus_assign_resources(parent);
95 	pci_bus_add_devices(parent);
96 	pci_enable_bridges(parent);
97 	return 0;
98 }
99 
100 int pciehp_unconfigure_device(struct slot *p_slot)
101 {
102 	int rc = 0;
103 	int j;
104 	u8 bctl = 0;
105 
106 	dbg("%s: bus/dev = %x/%x\n", __FUNCTION__, p_slot->bus,
107 				p_slot->device);
108 
109 	for (j=0; j<8 ; j++) {
110 		struct pci_dev* temp = pci_find_slot(p_slot->bus,
111 				(p_slot->device << 3) | j);
112 		if (!temp)
113 			continue;
114 		if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
115 			err("Cannot remove display device %s\n",
116 					pci_name(temp));
117 			continue;
118 		}
119 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
120 			pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
121 			if (bctl & PCI_BRIDGE_CTL_VGA) {
122 				err("Cannot remove display device %s\n",
123 						pci_name(temp));
124 				continue;
125 			}
126 		}
127 		pci_remove_bus_device(temp);
128 	}
129 	/*
130 	 * Some PCI Express root ports require fixup after hot-plug operation.
131 	 */
132 	if (pcie_mch_quirk)
133 		pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
134 
135 	return rc;
136 }
137 
138