xref: /openbmc/linux/drivers/pci/hotplug/shpchp_pci.c (revision 1eb4c977)
1 /*
2  * Standard 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 "shpchp.h"
36 
37 int __ref shpchp_configure_device(struct slot *p_slot)
38 {
39 	struct pci_dev *dev;
40 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
41 	int num, fn;
42 	struct controller *ctrl = p_slot->ctrl;
43 
44 	dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, 0));
45 	if (dev) {
46 		ctrl_err(ctrl, "Device %s already exists "
47 			 "at %04x:%02x:%02x, cannot hot-add\n", pci_name(dev),
48 			 pci_domain_nr(parent), p_slot->bus, p_slot->device);
49 		pci_dev_put(dev);
50 		return -EINVAL;
51 	}
52 
53 	num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
54 	if (num == 0) {
55 		ctrl_err(ctrl, "No new device found\n");
56 		return -ENODEV;
57 	}
58 
59 	for (fn = 0; fn < 8; fn++) {
60 		dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
61 		if (!dev)
62 			continue;
63 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
64 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
65 			/* Find an unused bus number for the new bridge */
66 			struct pci_bus *child;
67 			unsigned char busnr, start = parent->secondary;
68 			unsigned char end = parent->subordinate;
69 			for (busnr = start; busnr <= end; busnr++) {
70 				if (!pci_find_bus(pci_domain_nr(parent),
71 							busnr))
72 					break;
73 			}
74 			if (busnr > end) {
75 				ctrl_err(ctrl,
76 					 "No free bus for hot-added bridge\n");
77 				pci_dev_put(dev);
78 				continue;
79 			}
80 			child = pci_add_new_bus(parent, dev, busnr);
81 			if (!child) {
82 				ctrl_err(ctrl, "Cannot add new bus for %s\n",
83 					 pci_name(dev));
84 				pci_dev_put(dev);
85 				continue;
86 			}
87 			child->subordinate = pci_do_scan_bus(child);
88 			pci_bus_size_bridges(child);
89 		}
90 		pci_configure_slot(dev);
91 		pci_dev_put(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 shpchp_unconfigure_device(struct slot *p_slot)
101 {
102 	int rc = 0;
103 	int j;
104 	u8 bctl = 0;
105 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
106 	struct controller *ctrl = p_slot->ctrl;
107 
108 	ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:%02x\n",
109 		 __func__, pci_domain_nr(parent), p_slot->bus, p_slot->device);
110 
111 	for (j = 0; j < 8 ; j++) {
112 		struct pci_dev *temp = pci_get_slot(parent,
113 				(p_slot->device << 3) | j);
114 		if (!temp)
115 			continue;
116 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
117 			pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
118 			if (bctl & PCI_BRIDGE_CTL_VGA) {
119 				ctrl_err(ctrl,
120 					 "Cannot remove display device %s\n",
121 					 pci_name(temp));
122 				pci_dev_put(temp);
123 				rc = -EINVAL;
124 				break;
125 			}
126 		}
127 		pci_stop_and_remove_bus_device(temp);
128 		pci_dev_put(temp);
129 	}
130 	return rc;
131 }
132 
133