xref: /openbmc/linux/drivers/xen/pci.c (revision 94c7b6fc)
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 #ifdef CONFIG_PCI_MMCONFIG
30 #include <asm/pci_x86.h>
31 #endif
32 
33 static bool __read_mostly pci_seg_supported = true;
34 
35 static int xen_add_device(struct device *dev)
36 {
37 	int r;
38 	struct pci_dev *pci_dev = to_pci_dev(dev);
39 #ifdef CONFIG_PCI_IOV
40 	struct pci_dev *physfn = pci_dev->physfn;
41 #endif
42 
43 	if (pci_seg_supported) {
44 		struct physdev_pci_device_add add = {
45 			.seg = pci_domain_nr(pci_dev->bus),
46 			.bus = pci_dev->bus->number,
47 			.devfn = pci_dev->devfn
48 		};
49 #ifdef CONFIG_ACPI
50 		acpi_handle handle;
51 #endif
52 
53 #ifdef CONFIG_PCI_IOV
54 		if (pci_dev->is_virtfn) {
55 			add.flags = XEN_PCI_DEV_VIRTFN;
56 			add.physfn.bus = physfn->bus->number;
57 			add.physfn.devfn = physfn->devfn;
58 		} else
59 #endif
60 		if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
61 			add.flags = XEN_PCI_DEV_EXTFN;
62 
63 #ifdef CONFIG_ACPI
64 		handle = ACPI_HANDLE(&pci_dev->dev);
65 		if (!handle && pci_dev->bus->bridge)
66 			handle = ACPI_HANDLE(pci_dev->bus->bridge);
67 #ifdef CONFIG_PCI_IOV
68 		if (!handle && pci_dev->is_virtfn)
69 			handle = ACPI_HANDLE(physfn->bus->bridge);
70 #endif
71 		if (handle) {
72 			acpi_status status;
73 
74 			do {
75 				unsigned long long pxm;
76 
77 				status = acpi_evaluate_integer(handle, "_PXM",
78 							       NULL, &pxm);
79 				if (ACPI_SUCCESS(status)) {
80 					add.optarr[0] = pxm;
81 					add.flags |= XEN_PCI_DEV_PXM;
82 					break;
83 				}
84 				status = acpi_get_parent(handle, &handle);
85 			} while (ACPI_SUCCESS(status));
86 		}
87 #endif /* CONFIG_ACPI */
88 
89 		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
90 		if (r != -ENOSYS)
91 			return r;
92 		pci_seg_supported = false;
93 	}
94 
95 	if (pci_domain_nr(pci_dev->bus))
96 		r = -ENOSYS;
97 #ifdef CONFIG_PCI_IOV
98 	else if (pci_dev->is_virtfn) {
99 		struct physdev_manage_pci_ext manage_pci_ext = {
100 			.bus		= pci_dev->bus->number,
101 			.devfn		= pci_dev->devfn,
102 			.is_virtfn 	= 1,
103 			.physfn.bus	= physfn->bus->number,
104 			.physfn.devfn	= physfn->devfn,
105 		};
106 
107 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
108 			&manage_pci_ext);
109 	}
110 #endif
111 	else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
112 		struct physdev_manage_pci_ext manage_pci_ext = {
113 			.bus		= pci_dev->bus->number,
114 			.devfn		= pci_dev->devfn,
115 			.is_extfn	= 1,
116 		};
117 
118 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
119 			&manage_pci_ext);
120 	} else {
121 		struct physdev_manage_pci manage_pci = {
122 			.bus	= pci_dev->bus->number,
123 			.devfn	= pci_dev->devfn,
124 		};
125 
126 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
127 			&manage_pci);
128 	}
129 
130 	return r;
131 }
132 
133 static int xen_remove_device(struct device *dev)
134 {
135 	int r;
136 	struct pci_dev *pci_dev = to_pci_dev(dev);
137 
138 	if (pci_seg_supported) {
139 		struct physdev_pci_device device = {
140 			.seg = pci_domain_nr(pci_dev->bus),
141 			.bus = pci_dev->bus->number,
142 			.devfn = pci_dev->devfn
143 		};
144 
145 		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
146 					  &device);
147 	} else if (pci_domain_nr(pci_dev->bus))
148 		r = -ENOSYS;
149 	else {
150 		struct physdev_manage_pci manage_pci = {
151 			.bus = pci_dev->bus->number,
152 			.devfn = pci_dev->devfn
153 		};
154 
155 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
156 					  &manage_pci);
157 	}
158 
159 	return r;
160 }
161 
162 static int xen_pci_notifier(struct notifier_block *nb,
163 			    unsigned long action, void *data)
164 {
165 	struct device *dev = data;
166 	int r = 0;
167 
168 	switch (action) {
169 	case BUS_NOTIFY_ADD_DEVICE:
170 		r = xen_add_device(dev);
171 		break;
172 	case BUS_NOTIFY_DEL_DEVICE:
173 		r = xen_remove_device(dev);
174 		break;
175 	default:
176 		return NOTIFY_DONE;
177 	}
178 	if (r)
179 		dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
180 			action == BUS_NOTIFY_ADD_DEVICE ? "add" :
181 			(action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
182 	return NOTIFY_OK;
183 }
184 
185 static struct notifier_block device_nb = {
186 	.notifier_call = xen_pci_notifier,
187 };
188 
189 static int __init register_xen_pci_notifier(void)
190 {
191 	if (!xen_initial_domain())
192 		return 0;
193 
194 	return bus_register_notifier(&pci_bus_type, &device_nb);
195 }
196 
197 arch_initcall(register_xen_pci_notifier);
198 
199 #ifdef CONFIG_PCI_MMCONFIG
200 static int __init xen_mcfg_late(void)
201 {
202 	struct pci_mmcfg_region *cfg;
203 	int rc;
204 
205 	if (!xen_initial_domain())
206 		return 0;
207 
208 	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
209 		return 0;
210 
211 	if (list_empty(&pci_mmcfg_list))
212 		return 0;
213 
214 	/* Check whether they are in the right area. */
215 	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
216 		struct physdev_pci_mmcfg_reserved r;
217 
218 		r.address = cfg->address;
219 		r.segment = cfg->segment;
220 		r.start_bus = cfg->start_bus;
221 		r.end_bus = cfg->end_bus;
222 		r.flags = XEN_PCI_MMCFG_RESERVED;
223 
224 		rc = HYPERVISOR_physdev_op(PHYSDEVOP_pci_mmcfg_reserved, &r);
225 		switch (rc) {
226 		case 0:
227 		case -ENOSYS:
228 			continue;
229 
230 		default:
231 			pr_warn("Failed to report MMCONFIG reservation"
232 				" state for %s to hypervisor"
233 				" (%d)\n",
234 				cfg->name, rc);
235 		}
236 	}
237 	return 0;
238 }
239 /*
240  * Needs to be done after acpi_init which are subsys_initcall.
241  */
242 subsys_initcall_sync(xen_mcfg_late);
243 #endif
244