1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2008 Citrix Systems, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32#include <sys/param.h>
33#include <sys/bus.h>
34#include <sys/kernel.h>
35#include <sys/malloc.h>
36#include <sys/module.h>
37
38#include <machine/bus.h>
39#include <machine/resource.h>
40#include <sys/rman.h>
41
42#include <machine/stdarg.h>
43
44#include <xen/xen-os.h>
45#include <xen/features.h>
46#include <xen/hypervisor.h>
47#include <xen/hvm.h>
48#include <xen/xen_intr.h>
49
50#include <dev/pci/pcireg.h>
51#include <dev/pci/pcivar.h>
52
53#include <dev/xen/xenpci/xenpcivar.h>
54
55/*
56 * This is used to find our platform device instance.
57 */
58static devclass_t xenpci_devclass;
59
60static int
61xenpci_intr_filter(void *trap_frame)
62{
63	xen_intr_handle_upcall(trap_frame);
64	return (FILTER_HANDLED);
65}
66
67static int
68xenpci_irq_init(device_t device, struct xenpci_softc *scp)
69{
70	int error;
71
72	error = BUS_SETUP_INTR(device_get_parent(device), device,
73			       scp->res_irq, INTR_MPSAFE|INTR_TYPE_MISC,
74			       xenpci_intr_filter, NULL, /*trap_frame*/NULL,
75			       &scp->intr_cookie);
76	if (error)
77		return error;
78
79#ifdef SMP
80	/*
81	 * When using the PCI event delivery callback we cannot assign
82	 * events to specific vCPUs, so all events are delivered to vCPU#0 by
83	 * Xen. Since the PCI interrupt can fire on any CPU by default, we
84	 * need to bind it to vCPU#0 in order to ensure that
85	 * xen_intr_handle_upcall always gets called on vCPU#0.
86	 */
87	error = BUS_BIND_INTR(device_get_parent(device), device,
88	                      scp->res_irq, 0);
89	if (error)
90		return error;
91#endif
92
93	xen_hvm_set_callback(device);
94	return (0);
95}
96
97/*
98 * Deallocate anything allocated by xenpci_allocate_resources.
99 */
100static int
101xenpci_deallocate_resources(device_t dev)
102{
103	struct xenpci_softc *scp = device_get_softc(dev);
104
105	if (scp->res_irq != 0) {
106		bus_deactivate_resource(dev, SYS_RES_IRQ,
107			scp->rid_irq, scp->res_irq);
108		bus_release_resource(dev, SYS_RES_IRQ,
109			scp->rid_irq, scp->res_irq);
110		scp->res_irq = 0;
111	}
112
113	return (0);
114}
115
116/*
117 * Allocate irq and memory resources.
118 */
119static int
120xenpci_allocate_resources(device_t dev)
121{
122	struct xenpci_softc *scp = device_get_softc(dev);
123
124	scp->res_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ,
125			&scp->rid_irq, RF_SHAREABLE|RF_ACTIVE);
126	if (scp->res_irq == NULL) {
127		printf("xenpci Could not allocate irq.\n");
128		goto errexit;
129	}
130
131	return (0);
132
133errexit:
134	/* Cleanup anything we may have assigned. */
135	xenpci_deallocate_resources(dev);
136	return (ENXIO); /* For want of a better idea. */
137}
138
139/*
140 * Probe - just check device ID.
141 */
142static int
143xenpci_probe(device_t dev)
144{
145
146	if (pci_get_devid(dev) != 0x00015853)
147		return (ENXIO);
148
149	device_set_desc(dev, "Xen Platform Device");
150	return (BUS_PROBE_DEFAULT);
151}
152
153/*
154 * Attach - find resources and talk to Xen.
155 */
156static int
157xenpci_attach(device_t dev)
158{
159	struct xenpci_softc *scp = device_get_softc(dev);
160	int error;
161
162	error = xenpci_allocate_resources(dev);
163	if (error) {
164		device_printf(dev, "xenpci_allocate_resources failed(%d).\n",
165		    error);
166		goto errexit;
167	}
168
169	/*
170	 * Hook the irq up to evtchn
171	 */
172	error = xenpci_irq_init(dev, scp);
173	if (error) {
174		device_printf(dev, "xenpci_irq_init failed(%d).\n",
175			error);
176		goto errexit;
177	}
178
179	return (0);
180
181errexit:
182	/*
183	 * Undo anything we may have done.
184	 */
185	xenpci_deallocate_resources(dev);
186	return (error);
187}
188
189/*
190 * Detach - reverse anything done by attach.
191 */
192static int
193xenpci_detach(device_t dev)
194{
195	struct xenpci_softc *scp = device_get_softc(dev);
196	device_t parent = device_get_parent(dev);
197
198	/*
199	 * Take our interrupt handler out of the list of handlers
200	 * that can handle this irq.
201	 */
202	if (scp->intr_cookie != NULL) {
203		if (BUS_TEARDOWN_INTR(parent, dev,
204		    scp->res_irq, scp->intr_cookie) != 0)
205			device_printf(dev,
206			    "intr teardown failed.. continuing\n");
207		scp->intr_cookie = NULL;
208	}
209
210	/*
211	 * Deallocate any system resources we may have
212	 * allocated on behalf of this driver.
213	 */
214	return (xenpci_deallocate_resources(dev));
215}
216
217static int
218xenpci_resume(device_t dev)
219{
220	xen_hvm_set_callback(dev);
221	return (0);
222}
223
224static device_method_t xenpci_methods[] = {
225	/* Device interface */
226	DEVMETHOD(device_probe,		xenpci_probe),
227	DEVMETHOD(device_attach,	xenpci_attach),
228	DEVMETHOD(device_detach,	xenpci_detach),
229	DEVMETHOD(device_resume,	xenpci_resume),
230	{ 0, 0 }
231};
232
233static driver_t xenpci_driver = {
234	"xenpci",
235	xenpci_methods,
236	sizeof(struct xenpci_softc),
237};
238
239DRIVER_MODULE(xenpci, pci, xenpci_driver, xenpci_devclass, 0, 0);
240