xref: /freebsd/sys/dev/xen/xenpci/xenpci.c (revision 27650413eae21a4cb2b48f13148125eb94b40ea9)
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 static device_t nexus;
55 
56 /*
57  * This is used to find our platform device instance.
58  */
59 static devclass_t xenpci_devclass;
60 
61 static int
62 xenpci_intr_filter(void *trap_frame)
63 {
64 	xen_intr_handle_upcall(trap_frame);
65 	return (FILTER_HANDLED);
66 }
67 
68 static int
69 xenpci_irq_init(device_t device, struct xenpci_softc *scp)
70 {
71 	int error;
72 
73 	error = BUS_SETUP_INTR(device_get_parent(device), device,
74 			       scp->res_irq, INTR_MPSAFE|INTR_TYPE_MISC,
75 			       xenpci_intr_filter, NULL, /*trap_frame*/NULL,
76 			       &scp->intr_cookie);
77 	if (error)
78 		return error;
79 
80 #ifdef SMP
81 	/*
82 	 * When using the PCI event delivery callback we cannot assign
83 	 * events to specific vCPUs, so all events are delivered to vCPU#0 by
84 	 * Xen. Since the PCI interrupt can fire on any CPU by default, we
85 	 * need to bind it to vCPU#0 in order to ensure that
86 	 * xen_intr_handle_upcall always gets called on vCPU#0.
87 	 */
88 	error = BUS_BIND_INTR(device_get_parent(device), device,
89 	                      scp->res_irq, 0);
90 	if (error)
91 		return error;
92 #endif
93 
94 	xen_hvm_set_callback(device);
95 	return (0);
96 }
97 
98 /*
99  * Deallocate anything allocated by xenpci_allocate_resources.
100  */
101 static int
102 xenpci_deallocate_resources(device_t dev)
103 {
104 	struct xenpci_softc *scp = device_get_softc(dev);
105 
106 	if (scp->res_irq != 0) {
107 		bus_deactivate_resource(dev, SYS_RES_IRQ,
108 			scp->rid_irq, scp->res_irq);
109 		bus_release_resource(dev, SYS_RES_IRQ,
110 			scp->rid_irq, scp->res_irq);
111 		scp->res_irq = 0;
112 	}
113 	if (scp->res_memory != 0) {
114 		bus_deactivate_resource(dev, SYS_RES_MEMORY,
115 			scp->rid_memory, scp->res_memory);
116 		bus_release_resource(dev, SYS_RES_MEMORY,
117 			scp->rid_memory, scp->res_memory);
118 		scp->res_memory = 0;
119 	}
120 
121 	return (0);
122 }
123 
124 /*
125  * Allocate irq and memory resources.
126  */
127 static int
128 xenpci_allocate_resources(device_t dev)
129 {
130 	struct xenpci_softc *scp = device_get_softc(dev);
131 
132 	scp->res_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ,
133 			&scp->rid_irq, RF_SHAREABLE|RF_ACTIVE);
134 	if (scp->res_irq == NULL) {
135 		printf("xenpci Could not allocate irq.\n");
136 		goto errexit;
137 	}
138 
139 	scp->rid_memory = PCIR_BAR(1);
140 	scp->res_memory = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
141 			&scp->rid_memory, RF_ACTIVE);
142 	if (scp->res_memory == NULL) {
143 		printf("xenpci Could not allocate memory bar.\n");
144 		goto errexit;
145 	}
146 
147 	scp->phys_next = rman_get_start(scp->res_memory);
148 
149 	return (0);
150 
151 errexit:
152 	/* Cleanup anything we may have assigned. */
153 	xenpci_deallocate_resources(dev);
154 	return (ENXIO); /* For want of a better idea. */
155 }
156 
157 /*
158  * Allocate a physical address range from our mmio region.
159  */
160 static int
161 xenpci_alloc_space_int(struct xenpci_softc *scp, size_t sz,
162     vm_paddr_t *pa)
163 {
164 
165 	if (scp->phys_next + sz > rman_get_end(scp->res_memory)) {
166 		return (ENOMEM);
167 	}
168 
169 	*pa = scp->phys_next;
170 	scp->phys_next += sz;
171 
172 	return (0);
173 }
174 
175 /*
176  * Allocate a physical address range from our mmio region.
177  */
178 int
179 xenpci_alloc_space(size_t sz, vm_paddr_t *pa)
180 {
181 	device_t dev = devclass_get_device(xenpci_devclass, 0);
182 
183 	if (dev) {
184 		return (xenpci_alloc_space_int(device_get_softc(dev),
185 			sz, pa));
186 	} else {
187 		return (ENOMEM);
188 	}
189 }
190 
191 static struct resource *
192 xenpci_alloc_resource(device_t dev, device_t child, int type, int *rid,
193     u_long start, u_long end, u_long count, u_int flags)
194 {
195 	return (BUS_ALLOC_RESOURCE(nexus, child, type, rid, start,
196 	    end, count, flags));
197 }
198 
199 
200 static int
201 xenpci_release_resource(device_t dev, device_t child, int type, int rid,
202     struct resource *r)
203 {
204 	return (BUS_RELEASE_RESOURCE(nexus, child, type, rid, r));
205 }
206 
207 static int
208 xenpci_activate_resource(device_t dev, device_t child, int type, int rid,
209     struct resource *r)
210 {
211 	return (BUS_ACTIVATE_RESOURCE(nexus, child, type, rid, r));
212 }
213 
214 static int
215 xenpci_deactivate_resource(device_t dev, device_t child, int type,
216     int rid, struct resource *r)
217 {
218 	return (BUS_DEACTIVATE_RESOURCE(nexus, child, type, rid, r));
219 }
220 
221 /*
222  * Probe - just check device ID.
223  */
224 static int
225 xenpci_probe(device_t dev)
226 {
227 
228 	if (pci_get_devid(dev) != 0x00015853)
229 		return (ENXIO);
230 
231 	device_set_desc(dev, "Xen Platform Device");
232 	return (bus_generic_probe(dev));
233 }
234 
235 /*
236  * Attach - find resources and talk to Xen.
237  */
238 static int
239 xenpci_attach(device_t dev)
240 {
241 	struct xenpci_softc *scp = device_get_softc(dev);
242 	devclass_t dc;
243 	int error;
244 
245 	/*
246 	 * Find and record nexus0.  Since we are not really on the
247 	 * PCI bus, all resource operations are directed to nexus
248 	 * instead of through our parent.
249 	 */
250 	if ((dc = devclass_find("nexus"))  == 0
251 	 || (nexus = devclass_get_device(dc, 0)) == 0) {
252 		device_printf(dev, "unable to find nexus.");
253 		return (ENOENT);
254 	}
255 
256 	error = xenpci_allocate_resources(dev);
257 	if (error) {
258 		device_printf(dev, "xenpci_allocate_resources failed(%d).\n",
259 		    error);
260 		goto errexit;
261 	}
262 
263 	/*
264 	 * Hook the irq up to evtchn
265 	 */
266 	error = xenpci_irq_init(dev, scp);
267 	if (error) {
268 		device_printf(dev, "xenpci_irq_init failed(%d).\n",
269 			error);
270 		goto errexit;
271 	}
272 
273 	return (bus_generic_attach(dev));
274 
275 errexit:
276 	/*
277 	 * Undo anything we may have done.
278 	 */
279 	xenpci_deallocate_resources(dev);
280 	return (error);
281 }
282 
283 /*
284  * Detach - reverse anything done by attach.
285  */
286 static int
287 xenpci_detach(device_t dev)
288 {
289 	struct xenpci_softc *scp = device_get_softc(dev);
290 	device_t parent = device_get_parent(dev);
291 
292 	/*
293 	 * Take our interrupt handler out of the list of handlers
294 	 * that can handle this irq.
295 	 */
296 	if (scp->intr_cookie != NULL) {
297 		if (BUS_TEARDOWN_INTR(parent, dev,
298 		    scp->res_irq, scp->intr_cookie) != 0)
299 			device_printf(dev,
300 			    "intr teardown failed.. continuing\n");
301 		scp->intr_cookie = NULL;
302 	}
303 
304 	/*
305 	 * Deallocate any system resources we may have
306 	 * allocated on behalf of this driver.
307 	 */
308 	return (xenpci_deallocate_resources(dev));
309 }
310 
311 static int
312 xenpci_suspend(device_t dev)
313 {
314 	return (bus_generic_suspend(dev));
315 }
316 
317 static int
318 xenpci_resume(device_t dev)
319 {
320 	xen_hvm_set_callback(dev);
321 	return (bus_generic_resume(dev));
322 }
323 
324 static device_method_t xenpci_methods[] = {
325 	/* Device interface */
326 	DEVMETHOD(device_probe,		xenpci_probe),
327 	DEVMETHOD(device_attach,	xenpci_attach),
328 	DEVMETHOD(device_detach,	xenpci_detach),
329 	DEVMETHOD(device_suspend,	xenpci_suspend),
330 	DEVMETHOD(device_resume,	xenpci_resume),
331 
332 	/* Bus interface */
333 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
334 	DEVMETHOD(bus_alloc_resource,   xenpci_alloc_resource),
335 	DEVMETHOD(bus_release_resource, xenpci_release_resource),
336 	DEVMETHOD(bus_activate_resource, xenpci_activate_resource),
337 	DEVMETHOD(bus_deactivate_resource, xenpci_deactivate_resource),
338 
339 	{ 0, 0 }
340 };
341 
342 static driver_t xenpci_driver = {
343 	"xenpci",
344 	xenpci_methods,
345 	sizeof(struct xenpci_softc),
346 };
347 
348 DRIVER_MODULE(xenpci, pci, xenpci_driver, xenpci_devclass, 0, 0);
349