xref: /openbmc/linux/drivers/pci/hotplug/pciehp_pci.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 		printk(KERN_WARNING "%s: Rev.%d type0 record not supported\n",
43 		       __FUNCTION__, hpp->revision);
44 		return;
45 	}
46 
47 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp->cache_line_size);
48 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp->latency_timer);
49 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
50 	if (hpp->enable_serr)
51 		pci_cmd |= PCI_COMMAND_SERR;
52 	else
53 		pci_cmd &= ~PCI_COMMAND_SERR;
54 	if (hpp->enable_perr)
55 		pci_cmd |= PCI_COMMAND_PARITY;
56 	else
57 		pci_cmd &= ~PCI_COMMAND_PARITY;
58 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
59 
60 	/* Program bridge control value */
61 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
62 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
63 				      hpp->latency_timer);
64 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
65 		if (hpp->enable_serr)
66 			pci_bctl |= PCI_BRIDGE_CTL_SERR;
67 		else
68 			pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
69 		if (hpp->enable_perr)
70 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
71 		else
72 			pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
73 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
74 	}
75 }
76 
77 static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
78 {
79 	int pos;
80 	u16 reg16;
81 	u32 reg32;
82 
83 	if (hpp->revision > 1) {
84 		printk(KERN_WARNING "%s: Rev.%d type2 record not supported\n",
85 		       __FUNCTION__, hpp->revision);
86 		return;
87 	}
88 
89 	/* Find PCI Express capability */
90 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
91 	if (!pos)
92 		return;
93 
94 	/* Initialize Device Control Register */
95 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &reg16);
96 	reg16 = (reg16 & hpp->pci_exp_devctl_and) | hpp->pci_exp_devctl_or;
97 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, reg16);
98 
99 	/* Initialize Link Control Register */
100 	if (dev->subordinate) {
101 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &reg16);
102 		reg16 = (reg16 & hpp->pci_exp_lnkctl_and)
103 			| hpp->pci_exp_lnkctl_or;
104 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, reg16);
105 	}
106 
107 	/* Find Advanced Error Reporting Enhanced Capability */
108 	pos = 256;
109 	do {
110 		pci_read_config_dword(dev, pos, &reg32);
111 		if (PCI_EXT_CAP_ID(reg32) == PCI_EXT_CAP_ID_ERR)
112 			break;
113 	} while ((pos = PCI_EXT_CAP_NEXT(reg32)));
114 	if (!pos)
115 		return;
116 
117 	/* Initialize Uncorrectable Error Mask Register */
118 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &reg32);
119 	reg32 = (reg32 & hpp->unc_err_mask_and) | hpp->unc_err_mask_or;
120 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
121 
122 	/* Initialize Uncorrectable Error Severity Register */
123 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &reg32);
124 	reg32 = (reg32 & hpp->unc_err_sever_and) | hpp->unc_err_sever_or;
125 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
126 
127 	/* Initialize Correctable Error Mask Register */
128 	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg32);
129 	reg32 = (reg32 & hpp->cor_err_mask_and) | hpp->cor_err_mask_or;
130 	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
131 
132 	/* Initialize Advanced Error Capabilities and Control Register */
133 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
134 	reg32 = (reg32 & hpp->adv_err_cap_and) | hpp->adv_err_cap_or;
135 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
136 
137 	/*
138 	 * FIXME: The following two registers are not supported yet.
139 	 *
140 	 *   o Secondary Uncorrectable Error Severity Register
141 	 *   o Secondary Uncorrectable Error Mask Register
142 	 */
143 }
144 
145 static void program_fw_provided_values(struct pci_dev *dev)
146 {
147 	struct pci_dev *cdev;
148 	struct hotplug_params hpp;
149 
150 	/* Program hpp values for this device */
151 	if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
152 			(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
153 			(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
154 		return;
155 
156 	if (pciehp_get_hp_params_from_firmware(dev, &hpp)) {
157 		printk(KERN_WARNING "%s: Could not get hotplug parameters\n",
158 		       __FUNCTION__);
159 		return;
160 	}
161 
162 	if (hpp.t2)
163 		program_hpp_type2(dev, hpp.t2);
164 	if (hpp.t0)
165 		program_hpp_type0(dev, hpp.t0);
166 
167 	/* Program child devices */
168 	if (dev->subordinate) {
169 		list_for_each_entry(cdev, &dev->subordinate->devices,
170 				    bus_list)
171 			program_fw_provided_values(cdev);
172 	}
173 }
174 
175 static int pciehp_add_bridge(struct pci_dev *dev)
176 {
177 	struct pci_bus *parent = dev->bus;
178 	int pass, busnr, start = parent->secondary;
179 	int end = parent->subordinate;
180 
181 	for (busnr = start; busnr <= end; busnr++) {
182 		if (!pci_find_bus(pci_domain_nr(parent), busnr))
183 			break;
184 	}
185 	if (busnr-- > end) {
186 		err("No bus number available for hot-added bridge %s\n",
187 				pci_name(dev));
188 		return -1;
189 	}
190 	for (pass = 0; pass < 2; pass++)
191 		busnr = pci_scan_bridge(parent, dev, busnr, pass);
192 	if (!dev->subordinate)
193 		return -1;
194 	pci_bus_size_bridges(dev->subordinate);
195 	pci_bus_assign_resources(parent);
196 	pci_enable_bridges(parent);
197 	pci_bus_add_devices(parent);
198 	return 0;
199 }
200 
201 int pciehp_configure_device(struct slot *p_slot)
202 {
203 	struct pci_dev *dev;
204 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
205 	int num, fn;
206 
207 	dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, 0));
208 	if (dev) {
209 		err("Device %s already exists at %x:%x, cannot hot-add\n",
210 				pci_name(dev), p_slot->bus, p_slot->device);
211 		pci_dev_put(dev);
212 		return -EINVAL;
213 	}
214 
215 	num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
216 	if (num == 0) {
217 		err("No new device found\n");
218 		return -ENODEV;
219 	}
220 
221 	for (fn = 0; fn < 8; fn++) {
222 		dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, fn));
223 		if (!dev)
224 			continue;
225 		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
226 			err("Cannot hot-add display device %s\n",
227 					pci_name(dev));
228 			pci_dev_put(dev);
229 			continue;
230 		}
231 		if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
232 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
233 			pciehp_add_bridge(dev);
234 		}
235 		program_fw_provided_values(dev);
236 		pci_dev_put(dev);
237 	}
238 
239 	pci_bus_assign_resources(parent);
240 	pci_bus_add_devices(parent);
241 	return 0;
242 }
243 
244 int pciehp_unconfigure_device(struct slot *p_slot)
245 {
246 	int ret, rc = 0;
247 	int j;
248 	u8 bctl = 0;
249 	u8 presence = 0;
250 	struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
251 
252 	dbg("%s: bus/dev = %x/%x\n", __FUNCTION__, p_slot->bus,
253 				p_slot->device);
254 
255 	for (j=0; j<8 ; j++) {
256 		struct pci_dev* temp = pci_get_slot(parent,
257 				(p_slot->device << 3) | j);
258 		if (!temp)
259 			continue;
260 		if ((temp->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
261 			err("Cannot remove display device %s\n",
262 					pci_name(temp));
263 			pci_dev_put(temp);
264 			continue;
265 		}
266 		if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
267 			ret = p_slot->hpc_ops->get_adapter_status(p_slot,
268 								&presence);
269 			if (!ret && presence) {
270 				pci_read_config_byte(temp, PCI_BRIDGE_CONTROL,
271 					&bctl);
272 				if (bctl & PCI_BRIDGE_CTL_VGA) {
273 					err("Cannot remove display device %s\n",
274 						pci_name(temp));
275 					pci_dev_put(temp);
276 					continue;
277 				}
278 			}
279 		}
280 		pci_remove_bus_device(temp);
281 		pci_dev_put(temp);
282 	}
283 	/*
284 	 * Some PCI Express root ports require fixup after hot-plug operation.
285 	 */
286 	if (pcie_mch_quirk)
287 		pci_fixup_device(pci_fixup_final, p_slot->ctrl->pci_dev);
288 
289 	return rc;
290 }
291 
292