xref: /freebsd/sys/dev/xen/xenpci/xenpci.c (revision aa64d12bcd48a0bb8e7a88bae0fad6d27ba34724)
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 
47 #include <dev/pci/pcireg.h>
48 #include <dev/pci/pcivar.h>
49 
50 #include <dev/xen/xenpci/xenpcivar.h>
51 
52 extern void xen_intr_handle_upcall(struct trapframe *trap_frame);
53 
54 /*
55  * This is used to find our platform device instance.
56  */
57 static devclass_t xenpci_devclass;
58 
59 static int
60 xenpci_intr_filter(void *trap_frame)
61 {
62 	xen_intr_handle_upcall(trap_frame);
63 	return (FILTER_HANDLED);
64 }
65 
66 static int
67 xenpci_irq_init(device_t device, struct xenpci_softc *scp)
68 {
69 	int error;
70 
71 	error = BUS_SETUP_INTR(device_get_parent(device), device,
72 			       scp->res_irq, INTR_MPSAFE|INTR_TYPE_MISC,
73 			       xenpci_intr_filter, NULL, /*trap_frame*/NULL,
74 			       &scp->intr_cookie);
75 	if (error)
76 		return error;
77 
78 #ifdef SMP
79 	/*
80 	 * When using the PCI event delivery callback we cannot assign
81 	 * events to specific vCPUs, so all events are delivered to vCPU#0 by
82 	 * Xen. Since the PCI interrupt can fire on any CPU by default, we
83 	 * need to bind it to vCPU#0 in order to ensure that
84 	 * xen_intr_handle_upcall always gets called on vCPU#0.
85 	 */
86 	error = BUS_BIND_INTR(device_get_parent(device), device,
87 	                      scp->res_irq, 0);
88 	if (error)
89 		return error;
90 #endif
91 
92 	xen_hvm_set_callback(device);
93 	return (0);
94 }
95 
96 /*
97  * Deallocate anything allocated by xenpci_allocate_resources.
98  */
99 static int
100 xenpci_deallocate_resources(device_t dev)
101 {
102 	struct xenpci_softc *scp = device_get_softc(dev);
103 
104 	if (scp->res_irq != 0) {
105 		bus_deactivate_resource(dev, SYS_RES_IRQ,
106 			scp->rid_irq, scp->res_irq);
107 		bus_release_resource(dev, SYS_RES_IRQ,
108 			scp->rid_irq, scp->res_irq);
109 		scp->res_irq = 0;
110 	}
111 	if (scp->res_memory != 0) {
112 		bus_deactivate_resource(dev, SYS_RES_MEMORY,
113 			scp->rid_memory, scp->res_memory);
114 		bus_release_resource(dev, SYS_RES_MEMORY,
115 			scp->rid_memory, scp->res_memory);
116 		scp->res_memory = 0;
117 	}
118 
119 	return (0);
120 }
121 
122 /*
123  * Allocate irq and memory resources.
124  */
125 static int
126 xenpci_allocate_resources(device_t dev)
127 {
128 	struct xenpci_softc *scp = device_get_softc(dev);
129 
130 	scp->res_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ,
131 			&scp->rid_irq, RF_SHAREABLE|RF_ACTIVE);
132 	if (scp->res_irq == NULL) {
133 		printf("xenpci Could not allocate irq.\n");
134 		goto errexit;
135 	}
136 
137 	scp->rid_memory = PCIR_BAR(1);
138 	scp->res_memory = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
139 			&scp->rid_memory, RF_ACTIVE);
140 	if (scp->res_memory == NULL) {
141 		printf("xenpci Could not allocate memory bar.\n");
142 		goto errexit;
143 	}
144 
145 	scp->phys_next = rman_get_start(scp->res_memory);
146 
147 	return (0);
148 
149 errexit:
150 	/* Cleanup anything we may have assigned. */
151 	xenpci_deallocate_resources(dev);
152 	return (ENXIO); /* For want of a better idea. */
153 }
154 
155 /*
156  * Allocate a physical address range from our mmio region.
157  */
158 static int
159 xenpci_alloc_space_int(struct xenpci_softc *scp, size_t sz,
160     vm_paddr_t *pa)
161 {
162 
163 	if (scp->phys_next + sz > rman_get_end(scp->res_memory)) {
164 		return (ENOMEM);
165 	}
166 
167 	*pa = scp->phys_next;
168 	scp->phys_next += sz;
169 
170 	return (0);
171 }
172 
173 /*
174  * Allocate a physical address range from our mmio region.
175  */
176 int
177 xenpci_alloc_space(size_t sz, vm_paddr_t *pa)
178 {
179 	device_t dev = devclass_get_device(xenpci_devclass, 0);
180 
181 	if (dev) {
182 		return (xenpci_alloc_space_int(device_get_softc(dev),
183 			sz, pa));
184 	} else {
185 		return (ENOMEM);
186 	}
187 }
188 
189 /*
190  * Probe - just check device ID.
191  */
192 static int
193 xenpci_probe(device_t dev)
194 {
195 
196 	if (pci_get_devid(dev) != 0x00015853)
197 		return (ENXIO);
198 
199 	device_set_desc(dev, "Xen Platform Device");
200 	return (BUS_PROBE_DEFAULT);
201 }
202 
203 /*
204  * Attach - find resources and talk to Xen.
205  */
206 static int
207 xenpci_attach(device_t dev)
208 {
209 	struct xenpci_softc *scp = device_get_softc(dev);
210 	int error;
211 
212 	error = xenpci_allocate_resources(dev);
213 	if (error) {
214 		device_printf(dev, "xenpci_allocate_resources failed(%d).\n",
215 		    error);
216 		goto errexit;
217 	}
218 
219 	/*
220 	 * Hook the irq up to evtchn
221 	 */
222 	error = xenpci_irq_init(dev, scp);
223 	if (error) {
224 		device_printf(dev, "xenpci_irq_init failed(%d).\n",
225 			error);
226 		goto errexit;
227 	}
228 
229 	return (0);
230 
231 errexit:
232 	/*
233 	 * Undo anything we may have done.
234 	 */
235 	xenpci_deallocate_resources(dev);
236 	return (error);
237 }
238 
239 /*
240  * Detach - reverse anything done by attach.
241  */
242 static int
243 xenpci_detach(device_t dev)
244 {
245 	struct xenpci_softc *scp = device_get_softc(dev);
246 	device_t parent = device_get_parent(dev);
247 
248 	/*
249 	 * Take our interrupt handler out of the list of handlers
250 	 * that can handle this irq.
251 	 */
252 	if (scp->intr_cookie != NULL) {
253 		if (BUS_TEARDOWN_INTR(parent, dev,
254 		    scp->res_irq, scp->intr_cookie) != 0)
255 			device_printf(dev,
256 			    "intr teardown failed.. continuing\n");
257 		scp->intr_cookie = NULL;
258 	}
259 
260 	/*
261 	 * Deallocate any system resources we may have
262 	 * allocated on behalf of this driver.
263 	 */
264 	return (xenpci_deallocate_resources(dev));
265 }
266 
267 static int
268 xenpci_resume(device_t dev)
269 {
270 	xen_hvm_set_callback(dev);
271 	return (0);
272 }
273 
274 static device_method_t xenpci_methods[] = {
275 	/* Device interface */
276 	DEVMETHOD(device_probe,		xenpci_probe),
277 	DEVMETHOD(device_attach,	xenpci_attach),
278 	DEVMETHOD(device_detach,	xenpci_detach),
279 	DEVMETHOD(device_resume,	xenpci_resume),
280 
281 	{ 0, 0 }
282 };
283 
284 static driver_t xenpci_driver = {
285 	"xenpci",
286 	xenpci_methods,
287 	sizeof(struct xenpci_softc),
288 };
289 
290 DRIVER_MODULE(xenpci, pci, xenpci_driver, xenpci_devclass, 0, 0);
291