xref: /linux/drivers/pci/hotplug/pciehp_pci.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
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 void program_hpp_type0(struct pci_dev *dev, struct hpp_type0 *hpp)
38 {
39 	u16 pci_cmd, pci_bctl;
40 
41 	if (hpp->revision > 1) {
42 		warn("Rev.%d type0 record not supported\n", hpp->revision);
43 		return;
44 	}
45 
46 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp->cache_line_size);
47 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp->latency_timer);
48 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
49 	if (hpp->enable_serr)
50 		pci_cmd |= PCI_COMMAND_SERR;
51 	else
52 		pci_cmd &= ~PCI_COMMAND_SERR;
53 	if (hpp->enable_perr)
54 		pci_cmd |= PCI_COMMAND_PARITY;
55 	else
56 		pci_cmd &= ~PCI_COMMAND_PARITY;
57 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
58 
59 	/* Program bridge control value */
60 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
61 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
62 				      hpp->latency_timer);
63 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
64 		if (hpp->enable_serr)
65 			pci_bctl |= PCI_BRIDGE_CTL_SERR;
66 		else
67 			pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
68 		if (hpp->enable_perr)
69 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
70 		else
71 			pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
72 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
73 	}
74 }
75 
76 static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
77 {
78 	int pos;
79 	u16 reg16;
80 	u32 reg32;
81 
82 	if (hpp->revision > 1) {
83 		warn("Rev.%d type2 record not supported\n", hpp->revision);
84 		return;
85 	}
86 
87 	/* Find PCI Express capability */
88 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
89 	if (!pos)
90 		return;
91 
92 	/* Initialize Device Control Register */
93 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &reg16);
94 	reg16 = (reg16 & hpp->pci_exp_devctl_and) | hpp->pci_exp_devctl_or;
95 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, reg16);
96 
97 	/* Initialize Link Control Register */
98 	if (dev->subordinate) {
99 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &reg16);
100 		reg16 = (reg16 & hpp->pci_exp_lnkctl_and)
101 			| hpp->pci_exp_lnkctl_or;
102 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, reg16);
103 	}
104 
105 	/* Find Advanced Error Reporting Enhanced Capability */
106 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
107 	if (!pos)
108 		return;
109 
110 	/* Initialize Uncorrectable Error Mask Register */
111 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &reg32);
112 	reg32 = (reg32 & hpp->unc_err_mask_and) | hpp->unc_err_mask_or;
113 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
114 
115 	/* Initialize Uncorrectable Error Severity Register */
116 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &reg32);
117 	reg32 = (reg32 & hpp->unc_err_sever_and) | hpp->unc_err_sever_or;
118 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
119 
120 	/* Initialize Correctable Error Mask Register */
121 	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg32);
122 	reg32 = (reg32 & hpp->cor_err_mask_and) | hpp->cor_err_mask_or;
123 	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
124 
125 	/* Initialize Advanced Error Capabilities and Control Register */
126 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
127 	reg32 = (reg32 & hpp->adv_err_cap_and) | hpp->adv_err_cap_or;
128 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
129 
130 	/*
131 	 * FIXME: The following two registers are not supported yet.
132 	 *
133 	 *   o Secondary Uncorrectable Error Severity Register
134 	 *   o Secondary Uncorrectable Error Mask Register
135 	 */
136 }
137 
138 static void program_fw_provided_values(struct pci_dev *dev)
139 {
140 	struct pci_dev *cdev;
141 	struct hotplug_params hpp;
142 
143 	/* Program hpp values for this device */
144 	if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
145 			(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
146 			(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
147 		return;
148 
149 	if (pciehp_get_hp_params_from_firmware(dev, &hpp)) {
150 		warn("Could not get hotplug parameters\n");
151 		return;
152 	}
153 
154 	if (hpp.t2)
155 		program_hpp_type2(dev, hpp.t2);
156 	if (hpp.t0)
157 		program_hpp_type0(dev, hpp.t0);
158 
159 	/* Program child devices */
160 	if (dev->subordinate) {
161 		list_for_each_entry(cdev, &dev->subordinate->devices,
162 				    bus_list)
163 			program_fw_provided_values(cdev);
164 	}
165 }
166 
167 static int __ref pciehp_add_bridge(struct pci_dev *dev)
168 {
169 	struct pci_bus *parent = dev->bus;
170 	int pass, busnr, start = parent->secondary;
171 	int end = parent->subordinate;
172 
173 	for (busnr = start; busnr <= end; busnr++) {
174 		if (!pci_find_bus(pci_domain_nr(parent), busnr))
175 			break;
176 	}
177 	if (busnr-- > end) {
178 		err("No bus number available for hot-added bridge %s\n",
179 				pci_name(dev));
180 		return -1;
181 	}
182 	for (pass = 0; pass < 2; pass++)
183 		busnr = pci_scan_bridge(parent, dev, busnr, pass);
184 	if (!dev->subordinate)
185 		return -1;
186 	pci_bus_size_bridges(dev->subordinate);
187 	pci_bus_assign_resources(parent);
188 	pci_enable_bridges(parent);
189 	pci_bus_add_devices(parent);
190 	return 0;
191 }
192 
193 int pciehp_configure_device(struct slot *p_slot)
194 {
195 	struct pci_dev *dev;
196 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
197 	int num, fn;
198 	struct controller *ctrl = p_slot->ctrl;
199 
200 	dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, 0));
201 	if (dev) {
202 		ctrl_err(ctrl, "Device %s already exists "
203 			 "at %04x:%02x:%02x, cannot hot-add\n", pci_name(dev),
204 			 pci_domain_nr(parent), p_slot->bus, p_slot->device);
205 		pci_dev_put(dev);
206 		return -EINVAL;
207 	}
208 
209 	num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
210 	if (num == 0) {
211 		ctrl_err(ctrl, "No new device found\n");
212 		return -ENODEV;
213 	}
214 
215 	for (fn = 0; fn < 8; fn++) {
216 		dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
217 		if (!dev)
218 			continue;
219 		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
220 			ctrl_err(ctrl, "Cannot hot-add display device %s\n",
221 				 pci_name(dev));
222 			pci_dev_put(dev);
223 			continue;
224 		}
225 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
226 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
227 			pciehp_add_bridge(dev);
228 		}
229 		program_fw_provided_values(dev);
230 		pci_dev_put(dev);
231 	}
232 
233 	pci_bus_assign_resources(parent);
234 	pci_bus_add_devices(parent);
235 	return 0;
236 }
237 
238 int pciehp_unconfigure_device(struct slot *p_slot)
239 {
240 	int ret, rc = 0;
241 	int j;
242 	u8 bctl = 0;
243 	u8 presence = 0;
244 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
245 	u16 command;
246 	struct controller *ctrl = p_slot->ctrl;
247 
248 	ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:%02x\n",
249 		 __func__, pci_domain_nr(parent), p_slot->bus, p_slot->device);
250 	ret = p_slot->hpc_ops->get_adapter_status(p_slot, &presence);
251 	if (ret)
252 		presence = 0;
253 
254 	for (j = 0; j < 8; j++) {
255 		struct pci_dev* temp = pci_get_slot(parent,
256 				(p_slot->device << 3) | j);
257 		if (!temp)
258 			continue;
259 		if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
260 			ctrl_err(ctrl, "Cannot remove display device %s\n",
261 				 pci_name(temp));
262 			pci_dev_put(temp);
263 			continue;
264 		}
265 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
266 			pci_read_config_byte(temp, PCI_BRIDGE_CONTROL, &bctl);
267 			if (bctl & PCI_BRIDGE_CTL_VGA) {
268 				ctrl_err(ctrl,
269 					 "Cannot remove display device %s\n",
270 					 pci_name(temp));
271 				pci_dev_put(temp);
272 				continue;
273 			}
274 		}
275 		pci_remove_bus_device(temp);
276 		/*
277 		 * Ensure that no new Requests will be generated from
278 		 * the device.
279 		 */
280 		if (presence) {
281 			pci_read_config_word(temp, PCI_COMMAND, &command);
282 			command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
283 			command |= PCI_COMMAND_INTX_DISABLE;
284 			pci_write_config_word(temp, PCI_COMMAND, command);
285 		}
286 		pci_dev_put(temp);
287 	}
288 	/*
289 	 * Some PCI Express root ports require fixup after hot-plug operation.
290 	 */
291 	if (pcie_mch_quirk)
292 		pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
293 
294 	return rc;
295 }
296