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