xref: /openbmc/linux/drivers/xen/pci.c (revision 12eb4683)
1 /*
2  * Copyright (c) 2009, Intel Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15  * Place - Suite 330, Boston, MA 02111-1307 USA.
16  *
17  * Author: Weidong Han <weidong.han@intel.com>
18  */
19 
20 #include <linux/pci.h>
21 #include <linux/acpi.h>
22 #include <xen/xen.h>
23 #include <xen/interface/physdev.h>
24 #include <xen/interface/xen.h>
25 
26 #include <asm/xen/hypervisor.h>
27 #include <asm/xen/hypercall.h>
28 #include "../pci/pci.h"
29 #include <asm/pci_x86.h>
30 
31 static bool __read_mostly pci_seg_supported = true;
32 
33 static int xen_add_device(struct device *dev)
34 {
35 	int r;
36 	struct pci_dev *pci_dev = to_pci_dev(dev);
37 #ifdef CONFIG_PCI_IOV
38 	struct pci_dev *physfn = pci_dev->physfn;
39 #endif
40 
41 	if (pci_seg_supported) {
42 		struct physdev_pci_device_add add = {
43 			.seg = pci_domain_nr(pci_dev->bus),
44 			.bus = pci_dev->bus->number,
45 			.devfn = pci_dev->devfn
46 		};
47 #ifdef CONFIG_ACPI
48 		acpi_handle handle;
49 #endif
50 
51 #ifdef CONFIG_PCI_IOV
52 		if (pci_dev->is_virtfn) {
53 			add.flags = XEN_PCI_DEV_VIRTFN;
54 			add.physfn.bus = physfn->bus->number;
55 			add.physfn.devfn = physfn->devfn;
56 		} else
57 #endif
58 		if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
59 			add.flags = XEN_PCI_DEV_EXTFN;
60 
61 #ifdef CONFIG_ACPI
62 		handle = ACPI_HANDLE(&pci_dev->dev);
63 		if (!handle && pci_dev->bus->bridge)
64 			handle = ACPI_HANDLE(pci_dev->bus->bridge);
65 #ifdef CONFIG_PCI_IOV
66 		if (!handle && pci_dev->is_virtfn)
67 			handle = ACPI_HANDLE(physfn->bus->bridge);
68 #endif
69 		if (handle) {
70 			acpi_status status;
71 
72 			do {
73 				unsigned long long pxm;
74 
75 				status = acpi_evaluate_integer(handle, "_PXM",
76 							       NULL, &pxm);
77 				if (ACPI_SUCCESS(status)) {
78 					add.optarr[0] = pxm;
79 					add.flags |= XEN_PCI_DEV_PXM;
80 					break;
81 				}
82 				status = acpi_get_parent(handle, &handle);
83 			} while (ACPI_SUCCESS(status));
84 		}
85 #endif /* CONFIG_ACPI */
86 
87 		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
88 		if (r != -ENOSYS)
89 			return r;
90 		pci_seg_supported = false;
91 	}
92 
93 	if (pci_domain_nr(pci_dev->bus))
94 		r = -ENOSYS;
95 #ifdef CONFIG_PCI_IOV
96 	else if (pci_dev->is_virtfn) {
97 		struct physdev_manage_pci_ext manage_pci_ext = {
98 			.bus		= pci_dev->bus->number,
99 			.devfn		= pci_dev->devfn,
100 			.is_virtfn 	= 1,
101 			.physfn.bus	= physfn->bus->number,
102 			.physfn.devfn	= physfn->devfn,
103 		};
104 
105 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
106 			&manage_pci_ext);
107 	}
108 #endif
109 	else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
110 		struct physdev_manage_pci_ext manage_pci_ext = {
111 			.bus		= pci_dev->bus->number,
112 			.devfn		= pci_dev->devfn,
113 			.is_extfn	= 1,
114 		};
115 
116 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
117 			&manage_pci_ext);
118 	} else {
119 		struct physdev_manage_pci manage_pci = {
120 			.bus	= pci_dev->bus->number,
121 			.devfn	= pci_dev->devfn,
122 		};
123 
124 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
125 			&manage_pci);
126 	}
127 
128 	return r;
129 }
130 
131 static int xen_remove_device(struct device *dev)
132 {
133 	int r;
134 	struct pci_dev *pci_dev = to_pci_dev(dev);
135 
136 	if (pci_seg_supported) {
137 		struct physdev_pci_device device = {
138 			.seg = pci_domain_nr(pci_dev->bus),
139 			.bus = pci_dev->bus->number,
140 			.devfn = pci_dev->devfn
141 		};
142 
143 		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
144 					  &device);
145 	} else if (pci_domain_nr(pci_dev->bus))
146 		r = -ENOSYS;
147 	else {
148 		struct physdev_manage_pci manage_pci = {
149 			.bus = pci_dev->bus->number,
150 			.devfn = pci_dev->devfn
151 		};
152 
153 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
154 					  &manage_pci);
155 	}
156 
157 	return r;
158 }
159 
160 static int xen_pci_notifier(struct notifier_block *nb,
161 			    unsigned long action, void *data)
162 {
163 	struct device *dev = data;
164 	int r = 0;
165 
166 	switch (action) {
167 	case BUS_NOTIFY_ADD_DEVICE:
168 		r = xen_add_device(dev);
169 		break;
170 	case BUS_NOTIFY_DEL_DEVICE:
171 		r = xen_remove_device(dev);
172 		break;
173 	default:
174 		return NOTIFY_DONE;
175 	}
176 	if (r)
177 		dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
178 			action == BUS_NOTIFY_ADD_DEVICE ? "add" :
179 			(action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
180 	return NOTIFY_OK;
181 }
182 
183 static struct notifier_block device_nb = {
184 	.notifier_call = xen_pci_notifier,
185 };
186 
187 static int __init register_xen_pci_notifier(void)
188 {
189 	if (!xen_initial_domain())
190 		return 0;
191 
192 	return bus_register_notifier(&pci_bus_type, &device_nb);
193 }
194 
195 arch_initcall(register_xen_pci_notifier);
196 
197 #ifdef CONFIG_PCI_MMCONFIG
198 static int __init xen_mcfg_late(void)
199 {
200 	struct pci_mmcfg_region *cfg;
201 	int rc;
202 
203 	if (!xen_initial_domain())
204 		return 0;
205 
206 	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
207 		return 0;
208 
209 	if (list_empty(&pci_mmcfg_list))
210 		return 0;
211 
212 	/* Check whether they are in the right area. */
213 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
214 		struct physdev_pci_mmcfg_reserved r;
215 
216 		r.address = cfg->address;
217 		r.segment = cfg->segment;
218 		r.start_bus = cfg->start_bus;
219 		r.end_bus = cfg->end_bus;
220 		r.flags = XEN_PCI_MMCFG_RESERVED;
221 
222 		rc = HYPERVISOR_physdev_op(PHYSDEVOP_pci_mmcfg_reserved, &r);
223 		switch (rc) {
224 		case 0:
225 		case -ENOSYS:
226 			continue;
227 
228 		default:
229 			pr_warn("Failed to report MMCONFIG reservation"
230 				" state for %s to hypervisor"
231 				" (%d)\n",
232 				cfg->name, rc);
233 		}
234 	}
235 	return 0;
236 }
237 /*
238  * Needs to be done after acpi_init which are subsys_initcall.
239  */
240 subsys_initcall_sync(xen_mcfg_late);
241 #endif
242