xref: /linux/drivers/pci/hotplug/shpchp_pci.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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 void program_fw_provided_values(struct pci_dev *dev)
38 {
39 	u16 pci_cmd, pci_bctl;
40 	struct pci_dev *cdev;
41 	struct hotplug_params hpp = {0x8, 0x40, 0, 0}; /* defaults */
42 
43 	/* Program hpp values for this device */
44 	if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
45 			(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
46 			(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
47 		return;
48 
49 	get_hp_params_from_firmware(dev, &hpp);
50 
51 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp.cache_line_size);
52 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp.latency_timer);
53 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
54 	if (hpp.enable_serr)
55 		pci_cmd |= PCI_COMMAND_SERR;
56 	else
57 		pci_cmd &= ~PCI_COMMAND_SERR;
58 	if (hpp.enable_perr)
59 		pci_cmd |= PCI_COMMAND_PARITY;
60 	else
61 		pci_cmd &= ~PCI_COMMAND_PARITY;
62 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
63 
64 	/* Program bridge control value and child devices */
65 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
66 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
67 				hpp.latency_timer);
68 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
69 		if (hpp.enable_serr)
70 			pci_bctl |= PCI_BRIDGE_CTL_SERR;
71 		else
72 			pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
73 		if (hpp.enable_perr)
74 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
75 		else
76 			pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
77 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
78 		if (dev->subordinate) {
79 			list_for_each_entry(cdev, &dev->subordinate->devices,
80 					bus_list)
81 				program_fw_provided_values(cdev);
82 		}
83 	}
84 }
85 
86 int shpchp_configure_device(struct slot *p_slot)
87 {
88 	struct pci_dev *dev;
89 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
90 	int num, fn;
91 
92 	dev = pci_find_slot(p_slot->bus, PCI_DEVFN(p_slot->device, 0));
93 	if (dev) {
94 		err("Device %s already exists at %x:%x, cannot hot-add\n",
95 				pci_name(dev), p_slot->bus, p_slot->device);
96 		return -EINVAL;
97 	}
98 
99 	num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
100 	if (num == 0) {
101 		err("No new device found\n");
102 		return -ENODEV;
103 	}
104 
105 	for (fn = 0; fn < 8; fn++) {
106 		if (!(dev = pci_find_slot(p_slot->bus,
107 					PCI_DEVFN(p_slot->device, fn))))
108 			continue;
109 		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
110 			err("Cannot hot-add display device %s\n",
111 					pci_name(dev));
112 			continue;
113 		}
114 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
115 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
116 			/* Find an unused bus number for the new bridge */
117 			struct pci_bus *child;
118 			unsigned char busnr, start = parent->secondary;
119 			unsigned char end = parent->subordinate;
120 			for (busnr = start; busnr <= end; busnr++) {
121 				if (!pci_find_bus(pci_domain_nr(parent),
122 							busnr))
123 					break;
124 			}
125 			if (busnr >= end) {
126 				err("No free bus for hot-added bridge\n");
127 				continue;
128 			}
129 			child = pci_add_new_bus(parent, dev, busnr);
130 			if (!child) {
131 				err("Cannot add new bus for %s\n",
132 						pci_name(dev));
133 				continue;
134 			}
135 			child->subordinate = pci_do_scan_bus(child);
136 			pci_bus_size_bridges(child);
137 		}
138 		program_fw_provided_values(dev);
139 	}
140 
141 	pci_bus_assign_resources(parent);
142 	pci_bus_add_devices(parent);
143 	pci_enable_bridges(parent);
144 	return 0;
145 }
146 
147 int shpchp_unconfigure_device(struct slot *p_slot)
148 {
149 	int rc = 0;
150 	int j;
151 	u8 bctl = 0;
152 
153 	dbg("%s: bus/dev = %x/%x\n", __FUNCTION__, p_slot->bus, p_slot->device);
154 
155 	for (j=0; j<8 ; j++) {
156 		struct pci_dev* temp = pci_find_slot(p_slot->bus,
157 				(p_slot->device << 3) | j);
158 		if (!temp)
159 			continue;
160 		if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
161 			err("Cannot remove display device %s\n",
162 					pci_name(temp));
163 			continue;
164 		}
165 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
166 			pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
167 			if (bctl & PCI_BRIDGE_CTL_VGA) {
168 				err("Cannot remove display device %s\n",
169 						pci_name(temp));
170 				continue;
171 			}
172 		}
173 		pci_remove_bus_device(temp);
174 	}
175 	return rc;
176 }
177 
178