xref: /dpdk/kernel/freebsd/nic_uio/nic_uio.c (revision 089e5ed727a15da2729cfee9b63533dd120bd04c)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 #include <sys/cdefs.h>
5 __FBSDID("$FreeBSD$");
6 
7 #include <sys/param.h> /* defines used in kernel.h */
8 #include <sys/module.h>
9 #include <sys/kernel.h> /* types used in module initialization */
10 #include <sys/conf.h> /* cdevsw struct */
11 #include <sys/bus.h> /* structs, prototypes for pci bus stuff and DEVMETHOD */
12 #include <sys/rman.h>
13 #include <sys/systm.h>
14 #include <sys/lock.h>
15 #include <sys/rwlock.h>
16 #include <sys/proc.h>
17 
18 #include <machine/bus.h>
19 #include <dev/pci/pcivar.h> /* For pci_get macros! */
20 #include <dev/pci/pcireg.h> /* The softc holds our per-instance data. */
21 #include <vm/vm.h>
22 #include <vm/uma.h>
23 #include <vm/vm_object.h>
24 #include <vm/vm_page.h>
25 #include <vm/vm_pager.h>
26 
27 
28 #define MAX_BARS (PCIR_MAX_BAR_0 + 1)
29 
30 #define MAX_DETACHED_DEVICES	128
31 static device_t detached_devices[MAX_DETACHED_DEVICES] = {};
32 static int num_detached = 0;
33 
34 struct nic_uio_softc {
35 	device_t        dev_t;
36 	struct cdev     *my_cdev;
37 	int              bar_id[MAX_BARS];
38 	struct resource *bar_res[MAX_BARS];
39 	u_long           bar_start[MAX_BARS];
40 	u_long           bar_size[MAX_BARS];
41 };
42 
43 /* Function prototypes */
44 static d_open_t         nic_uio_open;
45 static d_close_t        nic_uio_close;
46 static d_mmap_t         nic_uio_mmap;
47 static d_mmap_single_t  nic_uio_mmap_single;
48 static int              nic_uio_probe(device_t dev);
49 static int              nic_uio_attach(device_t dev);
50 static int              nic_uio_detach(device_t dev);
51 static int              nic_uio_shutdown(void);
52 static int              nic_uio_modevent(module_t mod, int type, void *arg);
53 
54 static struct cdevsw uio_cdevsw = {
55 		.d_name        = "nic_uio",
56 		.d_version     = D_VERSION,
57 		.d_open        = nic_uio_open,
58 		.d_close       = nic_uio_close,
59 		.d_mmap        = nic_uio_mmap,
60 		.d_mmap_single = nic_uio_mmap_single,
61 };
62 
63 static device_method_t nic_uio_methods[] = {
64 	DEVMETHOD(device_probe,    nic_uio_probe),
65 	DEVMETHOD(device_attach,   nic_uio_attach),
66 	DEVMETHOD(device_detach,   nic_uio_detach),
67 	DEVMETHOD_END
68 };
69 
70 struct device {
71     int vend;
72     int dev;
73 };
74 
75 struct pci_bdf {
76 	uint32_t bus;
77 	uint32_t devid;
78 	uint32_t function;
79 };
80 
81 static devclass_t nic_uio_devclass;
82 
83 DEFINE_CLASS_0(nic_uio, nic_uio_driver, nic_uio_methods, sizeof(struct nic_uio_softc));
84 DRIVER_MODULE(nic_uio, pci, nic_uio_driver, nic_uio_devclass, nic_uio_modevent, 0);
85 
86 static int
87 nic_uio_mmap(struct cdev *cdev, vm_ooffset_t offset, vm_paddr_t *paddr,
88 		int prot, vm_memattr_t *memattr)
89 {
90 	*paddr = offset;
91 	return 0;
92 }
93 
94 static int
95 nic_uio_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size,
96 		struct vm_object **obj, int nprot)
97 {
98 	/*
99 	 * The BAR index is encoded in the offset.  Divide the offset by
100 	 *  PAGE_SIZE to get the index of the bar requested by the user
101 	 *  app.
102 	 */
103 	unsigned bar = *offset/PAGE_SIZE;
104 	struct nic_uio_softc *sc = cdev->si_drv1;
105 
106 	if (bar >= MAX_BARS)
107 		return EINVAL;
108 
109 	if (sc->bar_res[bar] == NULL) {
110 		sc->bar_id[bar] = PCIR_BAR(bar);
111 
112 		if (PCI_BAR_IO(pci_read_config(sc->dev_t, sc->bar_id[bar], 4)))
113 			sc->bar_res[bar] = bus_alloc_resource_any(sc->dev_t, SYS_RES_IOPORT,
114 					&sc->bar_id[bar], RF_ACTIVE);
115 		else
116 			sc->bar_res[bar] = bus_alloc_resource_any(sc->dev_t, SYS_RES_MEMORY,
117 					&sc->bar_id[bar], RF_ACTIVE);
118 	}
119 	if (sc->bar_res[bar] == NULL)
120 		return ENXIO;
121 
122 	sc->bar_start[bar] = rman_get_start(sc->bar_res[bar]);
123 	sc->bar_size[bar] = rman_get_size(sc->bar_res[bar]);
124 
125 	device_printf(sc->dev_t, "Bar %u @ %lx, size %lx\n", bar,
126 			sc->bar_start[bar], sc->bar_size[bar]);
127 
128 	*offset = sc->bar_start[bar];
129 	*obj = vm_pager_allocate(OBJT_DEVICE, cdev, size, nprot, *offset,
130 				curthread->td_ucred);
131 	return 0;
132 }
133 
134 
135 int
136 nic_uio_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
137 {
138 	return 0;
139 }
140 
141 int
142 nic_uio_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
143 {
144 	return 0;
145 }
146 
147 static int
148 nic_uio_probe (device_t dev)
149 {
150 	int i;
151 	unsigned int bus = pci_get_bus(dev);
152 	unsigned int device = pci_get_slot(dev);
153 	unsigned int function = pci_get_function(dev);
154 
155 	char bdf_str[256];
156 	char *token, *remaining;
157 
158 	/* First check if we found this on load */
159 	for (i = 0; i < num_detached; i++)
160 		if (bus == pci_get_bus(detached_devices[i]) &&
161 		    device == pci_get_slot(detached_devices[i]) &&
162 		    function == pci_get_function(detached_devices[i])) {
163 			device_set_desc(dev, "DPDK PCI Device");
164 			return BUS_PROBE_SPECIFIC;
165 		}
166 
167 	/* otherwise check if it's a new device and if it matches the BDF */
168 	memset(bdf_str, 0, sizeof(bdf_str));
169 	TUNABLE_STR_FETCH("hw.nic_uio.bdfs", bdf_str, sizeof(bdf_str));
170 	remaining = bdf_str;
171 	while (1) {
172 		if (remaining == NULL || remaining[0] == '\0')
173 			break;
174 		token = strsep(&remaining, ",:");
175 		if (token == NULL)
176 			break;
177 		bus = strtol(token, NULL, 10);
178 		token = strsep(&remaining, ",:");
179 		if (token == NULL)
180 			break;
181 		device = strtol(token, NULL, 10);
182 		token = strsep(&remaining, ",:");
183 		if (token == NULL)
184 			break;
185 		function = strtol(token, NULL, 10);
186 
187 		if (bus == pci_get_bus(dev) &&
188 				device == pci_get_slot(dev) &&
189 				function == pci_get_function(dev)) {
190 
191 			if (num_detached < MAX_DETACHED_DEVICES) {
192 				printf("%s: probed dev=%p\n",
193 					       __func__, dev);
194 				detached_devices[num_detached++] = dev;
195 				device_set_desc(dev, "DPDK PCI Device");
196 				return BUS_PROBE_SPECIFIC;
197 			} else {
198 				printf("%s: reached MAX_DETACHED_DEVICES=%d. dev=%p won't be reattached\n",
199 						__func__, MAX_DETACHED_DEVICES,
200 						dev);
201 				break;
202 			}
203 		}
204 	}
205 
206 	return ENXIO;
207 }
208 
209 static int
210 nic_uio_attach(device_t dev)
211 {
212 	int i;
213 	struct nic_uio_softc *sc;
214 
215 	sc = device_get_softc(dev);
216 	sc->dev_t = dev;
217 	sc->my_cdev = make_dev(&uio_cdevsw, device_get_unit(dev),
218 			UID_ROOT, GID_WHEEL, 0600, "uio@pci:%u:%u:%u",
219 			pci_get_bus(dev), pci_get_slot(dev), pci_get_function(dev));
220 	if (sc->my_cdev == NULL)
221 		return ENXIO;
222 	sc->my_cdev->si_drv1 = sc;
223 
224 	for (i = 0; i < MAX_BARS; i++)
225 		sc->bar_res[i] = NULL;
226 
227 	pci_enable_busmaster(dev);
228 
229 	return 0;
230 }
231 
232 static int
233 nic_uio_detach(device_t dev)
234 {
235 	int i;
236 	struct nic_uio_softc *sc;
237 	sc = device_get_softc(dev);
238 
239 	for (i = 0; i < MAX_BARS; i++)
240 		if (sc->bar_res[i] != NULL) {
241 
242 			if (PCI_BAR_IO(pci_read_config(dev, sc->bar_id[i], 4)))
243 				bus_release_resource(dev, SYS_RES_IOPORT, sc->bar_id[i],
244 						sc->bar_res[i]);
245 			else
246 				bus_release_resource(dev, SYS_RES_MEMORY, sc->bar_id[i],
247 						sc->bar_res[i]);
248 		}
249 
250 	if (sc->my_cdev != NULL)
251 		destroy_dev(sc->my_cdev);
252 	return 0;
253 }
254 
255 static void
256 nic_uio_load(void)
257 {
258 	uint32_t bus, device, function;
259 	device_t dev;
260 	char bdf_str[256];
261 	char *token, *remaining;
262 
263 	memset(bdf_str, 0, sizeof(bdf_str));
264 	TUNABLE_STR_FETCH("hw.nic_uio.bdfs", bdf_str, sizeof(bdf_str));
265 	remaining = bdf_str;
266 	printf("nic_uio: hw.nic_uio.bdfs = '%s'\n", bdf_str);
267 	/*
268 	 * Users should specify PCI BDFs in the format "b:d:f,b:d:f,b:d:f".
269 	 *  But the code below does not try differentiate between : and ,
270 	 *  and just blindly uses 3 tokens at a time to construct a
271 	 *  bus/device/function tuple.
272 	 *
273 	 * There is no checking on strtol() return values, but this should
274 	 *  be OK.  Worst case is it cannot convert and returns 0.  This
275 	 *  could give us a different BDF than intended, but as long as the
276 	 *  PCI device/vendor ID does not match it will not matter.
277 	 */
278 	while (1) {
279 		if (remaining == NULL || remaining[0] == '\0')
280 			break;
281 		token = strsep(&remaining, ",:");
282 		if (token == NULL)
283 			break;
284 		bus = strtol(token, NULL, 10);
285 		token = strsep(&remaining, ",:");
286 		if (token == NULL)
287 			break;
288 		device = strtol(token, NULL, 10);
289 		token = strsep(&remaining, ",:");
290 		if (token == NULL)
291 			break;
292 		function = strtol(token, NULL, 10);
293 
294 		dev = pci_find_bsf(bus, device, function);
295 		if (dev == NULL)
296 			continue;
297 
298 		if (num_detached < MAX_DETACHED_DEVICES) {
299 			printf("nic_uio_load: detaching and storing dev=%p\n",
300 			       dev);
301 			detached_devices[num_detached++] = dev;
302 		} else {
303 			printf("nic_uio_load: reached MAX_DETACHED_DEVICES=%d. dev=%p won't be reattached\n",
304 			       MAX_DETACHED_DEVICES, dev);
305 		}
306 		device_detach(dev);
307 	}
308 }
309 
310 static void
311 nic_uio_unload(void)
312 {
313 	int i;
314 	printf("nic_uio_unload: entered...\n");
315 
316 	for (i = 0; i < num_detached; i++) {
317 		printf("nic_uio_unload: calling to device_probe_and_attach for dev=%p...\n",
318 			detached_devices[i]);
319 		device_probe_and_attach(detached_devices[i]);
320 		printf("nic_uio_unload: done.\n");
321 	}
322 
323 	printf("nic_uio_unload: leaving...\n");
324 }
325 
326 static int
327 nic_uio_shutdown(void)
328 {
329 	return 0;
330 }
331 
332 static int
333 nic_uio_modevent(module_t mod, int type, void *arg)
334 {
335 
336 	switch (type) {
337 	case MOD_LOAD:
338 		nic_uio_load();
339 		break;
340 	case MOD_UNLOAD:
341 		nic_uio_unload();
342 		break;
343 	case MOD_SHUTDOWN:
344 		nic_uio_shutdown();
345 		break;
346 	default:
347 		break;
348 	}
349 
350 	return 0;
351 }
352