xref: /freebsd/sys/dev/xen/xenpci/xenpci.c (revision ef90af83a58199ef3980d8c9a7dad07ec9b4bea3)
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 	/*
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 
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 static struct resource *
190 xenpci_alloc_resource(device_t dev, device_t child, int type, int *rid,
191     u_long start, u_long end, u_long count, u_int flags)
192 {
193 	return (BUS_ALLOC_RESOURCE(nexus, child, type, rid, start,
194 	    end, count, flags));
195 }
196 
197 
198 static int
199 xenpci_release_resource(device_t dev, device_t child, int type, int rid,
200     struct resource *r)
201 {
202 	return (BUS_RELEASE_RESOURCE(nexus, child, type, rid, r));
203 }
204 
205 static int
206 xenpci_activate_resource(device_t dev, device_t child, int type, int rid,
207     struct resource *r)
208 {
209 	return (BUS_ACTIVATE_RESOURCE(nexus, child, type, rid, r));
210 }
211 
212 static int
213 xenpci_deactivate_resource(device_t dev, device_t child, int type,
214     int rid, struct resource *r)
215 {
216 	return (BUS_DEACTIVATE_RESOURCE(nexus, child, type, rid, r));
217 }
218 
219 /*
220  * Probe - just check device ID.
221  */
222 static int
223 xenpci_probe(device_t dev)
224 {
225 
226 	if (pci_get_devid(dev) != 0x00015853)
227 		return (ENXIO);
228 
229 	device_set_desc(dev, "Xen Platform Device");
230 	return (bus_generic_probe(dev));
231 }
232 
233 /*
234  * Attach - find resources and talk to Xen.
235  */
236 static int
237 xenpci_attach(device_t dev)
238 {
239 	struct xenpci_softc *scp = device_get_softc(dev);
240 	devclass_t dc;
241 	int error;
242 
243 	/*
244 	 * Find and record nexus0.  Since we are not really on the
245 	 * PCI bus, all resource operations are directed to nexus
246 	 * instead of through our parent.
247 	 */
248 	if ((dc = devclass_find("nexus"))  == 0
249 	 || (nexus = devclass_get_device(dc, 0)) == 0) {
250 		device_printf(dev, "unable to find nexus.");
251 		return (ENOENT);
252 	}
253 
254 	error = xenpci_allocate_resources(dev);
255 	if (error) {
256 		device_printf(dev, "xenpci_allocate_resources failed(%d).\n",
257 		    error);
258 		goto errexit;
259 	}
260 
261 	/*
262 	 * Hook the irq up to evtchn
263 	 */
264 	error = xenpci_irq_init(dev, scp);
265 	if (error) {
266 		device_printf(dev, "xenpci_irq_init failed(%d).\n",
267 			error);
268 		goto errexit;
269 	}
270 
271 	return (bus_generic_attach(dev));
272 
273 errexit:
274 	/*
275 	 * Undo anything we may have done.
276 	 */
277 	xenpci_deallocate_resources(dev);
278 	return (error);
279 }
280 
281 /*
282  * Detach - reverse anything done by attach.
283  */
284 static int
285 xenpci_detach(device_t dev)
286 {
287 	struct xenpci_softc *scp = device_get_softc(dev);
288 	device_t parent = device_get_parent(dev);
289 
290 	/*
291 	 * Take our interrupt handler out of the list of handlers
292 	 * that can handle this irq.
293 	 */
294 	if (scp->intr_cookie != NULL) {
295 		if (BUS_TEARDOWN_INTR(parent, dev,
296 		    scp->res_irq, scp->intr_cookie) != 0)
297 			device_printf(dev,
298 			    "intr teardown failed.. continuing\n");
299 		scp->intr_cookie = NULL;
300 	}
301 
302 	/*
303 	 * Deallocate any system resources we may have
304 	 * allocated on behalf of this driver.
305 	 */
306 	return (xenpci_deallocate_resources(dev));
307 }
308 
309 static int
310 xenpci_suspend(device_t dev)
311 {
312 	struct xenpci_softc *scp = device_get_softc(dev);
313 	device_t parent = device_get_parent(dev);
314 
315 	if (scp->intr_cookie != NULL) {
316 		if (BUS_TEARDOWN_INTR(parent, dev, scp->res_irq,
317 		    scp->intr_cookie) != 0)
318 			printf("intr teardown failed.. continuing\n");
319 		scp->intr_cookie = NULL;
320 	}
321 
322 	return (bus_generic_suspend(dev));
323 }
324 
325 static int
326 xenpci_resume(device_t dev)
327 {
328 	struct xenpci_softc *scp = device_get_softc(dev);
329 	device_t parent = device_get_parent(dev);
330 
331 	BUS_SETUP_INTR(parent, dev, scp->res_irq,
332 	    INTR_MPSAFE|INTR_TYPE_MISC, xenpci_intr_filter, NULL,
333 	    /*trap_frame*/NULL, &scp->intr_cookie);
334 	xen_hvm_set_callback(dev);
335 	return (bus_generic_resume(dev));
336 }
337 
338 static device_method_t xenpci_methods[] = {
339 	/* Device interface */
340 	DEVMETHOD(device_probe,		xenpci_probe),
341 	DEVMETHOD(device_attach,	xenpci_attach),
342 	DEVMETHOD(device_detach,	xenpci_detach),
343 	DEVMETHOD(device_suspend,	xenpci_suspend),
344 	DEVMETHOD(device_resume,	xenpci_resume),
345 
346 	/* Bus interface */
347 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
348 	DEVMETHOD(bus_alloc_resource,   xenpci_alloc_resource),
349 	DEVMETHOD(bus_release_resource, xenpci_release_resource),
350 	DEVMETHOD(bus_activate_resource, xenpci_activate_resource),
351 	DEVMETHOD(bus_deactivate_resource, xenpci_deactivate_resource),
352 
353 	{ 0, 0 }
354 };
355 
356 static driver_t xenpci_driver = {
357 	"xenpci",
358 	xenpci_methods,
359 	sizeof(struct xenpci_softc),
360 };
361 
362 DRIVER_MODULE(xenpci, pci, xenpci_driver, xenpci_devclass, 0, 0);
363