xref: /freebsd/sys/riscv/riscv/nexus.c (revision 7cc42f6d)
1 /*-
2  * Copyright 1998 Massachusetts Institute of Technology
3  *
4  * Permission to use, copy, modify, and distribute this software and
5  * its documentation for any purpose and without fee is hereby
6  * granted, provided that both the above copyright notice and this
7  * permission notice appear in all copies, that both the above
8  * copyright notice and this permission notice appear in all
9  * supporting documentation, and that the name of M.I.T. not be used
10  * in advertising or publicity pertaining to distribution of the
11  * software without specific, written prior permission.  M.I.T. makes
12  * no representations about the suitability of this software for any
13  * purpose.  It is provided "as is" without express or implied
14  * warranty.
15  *
16  * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
17  * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20  * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  */
30 
31 /*
32  * This code implements a `root nexus' for RISC-V Architecture
33  * machines.  The function of the root nexus is to serve as an
34  * attachment point for both processors and buses, and to manage
35  * resources which are common to all of them.  In particular,
36  * this code implements the core resource managers for interrupt
37  * requests, DMA requests (which rightfully should be a part of the
38  * ISA code but it's easier to do it here for now), I/O port addresses,
39  * and I/O memory address space.
40  */
41 #include "opt_platform.h"
42 
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bus.h>
49 #include <sys/kernel.h>
50 #include <sys/malloc.h>
51 #include <sys/module.h>
52 #include <sys/rman.h>
53 #include <sys/interrupt.h>
54 
55 #include <machine/bus.h>
56 #include <machine/resource.h>
57 #include <machine/intr.h>
58 
59 #ifdef FDT
60 #include <dev/ofw/ofw_bus_subr.h>
61 #include <dev/ofw/openfirm.h>
62 #include "ofw_bus_if.h"
63 #endif
64 
65 extern struct bus_space memmap_bus;
66 
67 static MALLOC_DEFINE(M_NEXUSDEV, "nexusdev", "Nexus device");
68 
69 struct nexus_device {
70 	struct resource_list	nx_resources;
71 };
72 
73 #define DEVTONX(dev)	((struct nexus_device *)device_get_ivars(dev))
74 
75 static struct rman mem_rman;
76 static struct rman irq_rman;
77 
78 static device_probe_t nexus_fdt_probe;
79 static int nexus_attach(device_t);
80 
81 static	int nexus_print_child(device_t, device_t);
82 static	device_t nexus_add_child(device_t, u_int, const char *, int);
83 static	struct resource *nexus_alloc_resource(device_t, device_t, int, int *,
84     u_long, u_long, u_long, u_int);
85 static	int nexus_activate_resource(device_t, device_t, int, int,
86     struct resource *);
87 static int nexus_config_intr(device_t dev, int irq, enum intr_trigger trig,
88     enum intr_polarity pol);
89 static struct resource_list *nexus_get_reslist(device_t, device_t);
90 static	int nexus_set_resource(device_t, device_t, int, int, u_long, u_long);
91 static	int nexus_deactivate_resource(device_t, device_t, int, int,
92     struct resource *);
93 
94 static int nexus_setup_intr(device_t dev, device_t child, struct resource *res,
95     int flags, driver_filter_t *filt, driver_intr_t *intr, void *arg, void **cookiep);
96 static int nexus_teardown_intr(device_t, device_t, struct resource *, void *);
97 
98 static int nexus_ofw_map_intr(device_t dev, device_t child, phandle_t iparent,
99     int icells, pcell_t *intr);
100 
101 static device_method_t nexus_methods[] = {
102 	/* Device interface */
103 	DEVMETHOD(device_probe,		nexus_fdt_probe),
104 	DEVMETHOD(device_attach,	nexus_attach),
105 
106 	/* OFW interface */
107 	DEVMETHOD(ofw_bus_map_intr,	nexus_ofw_map_intr),
108 
109 	/* Bus interface */
110 	DEVMETHOD(bus_print_child,	nexus_print_child),
111 	DEVMETHOD(bus_add_child,	nexus_add_child),
112 	DEVMETHOD(bus_alloc_resource,	nexus_alloc_resource),
113 	DEVMETHOD(bus_activate_resource,	nexus_activate_resource),
114 	DEVMETHOD(bus_config_intr,	nexus_config_intr),
115 	DEVMETHOD(bus_get_resource_list, nexus_get_reslist),
116 	DEVMETHOD(bus_set_resource,	nexus_set_resource),
117 	DEVMETHOD(bus_deactivate_resource,	nexus_deactivate_resource),
118 	DEVMETHOD(bus_setup_intr,	nexus_setup_intr),
119 	DEVMETHOD(bus_teardown_intr,	nexus_teardown_intr),
120 	{ 0, 0 }
121 };
122 
123 static driver_t nexus_fdt_driver = {
124 	"nexus",
125 	nexus_methods,
126 	1			/* no softc */
127 };
128 
129 static int
130 nexus_fdt_probe(device_t dev)
131 {
132 
133 	device_quiet(dev);
134 	return (BUS_PROBE_DEFAULT);
135 }
136 
137 static int
138 nexus_attach(device_t dev)
139 {
140 
141 	mem_rman.rm_start = 0;
142 	mem_rman.rm_end = BUS_SPACE_MAXADDR;
143 	mem_rman.rm_type = RMAN_ARRAY;
144 	mem_rman.rm_descr = "I/O memory addresses";
145 	if (rman_init(&mem_rman) ||
146 	    rman_manage_region(&mem_rman, 0, BUS_SPACE_MAXADDR))
147 		panic("nexus_attach mem_rman");
148 	irq_rman.rm_start = 0;
149 	irq_rman.rm_end = ~0;
150 	irq_rman.rm_type = RMAN_ARRAY;
151 	irq_rman.rm_descr = "Interrupts";
152 	if (rman_init(&irq_rman) || rman_manage_region(&irq_rman, 0, ~0))
153 		panic("nexus_attach irq_rman");
154 
155 	nexus_add_child(dev, 8, "timer", 0);
156 	nexus_add_child(dev, 9, "rcons", 0);
157 	nexus_add_child(dev, 10, "ofwbus", 0);
158 
159 	bus_generic_probe(dev);
160 	bus_generic_attach(dev);
161 
162 	return (0);
163 }
164 
165 static int
166 nexus_print_child(device_t bus, device_t child)
167 {
168 	int retval = 0;
169 
170 	retval += bus_print_child_header(bus, child);
171 	retval += printf("\n");
172 
173 	return (retval);
174 }
175 
176 static device_t
177 nexus_add_child(device_t bus, u_int order, const char *name, int unit)
178 {
179 	device_t child;
180 	struct nexus_device *ndev;
181 
182 	ndev = malloc(sizeof(struct nexus_device), M_NEXUSDEV, M_NOWAIT|M_ZERO);
183 	if (!ndev)
184 		return (0);
185 	resource_list_init(&ndev->nx_resources);
186 
187 	child = device_add_child_ordered(bus, order, name, unit);
188 
189 	/* should we free this in nexus_child_detached? */
190 	device_set_ivars(child, ndev);
191 
192 	return (child);
193 }
194 
195 /*
196  * Allocate a resource on behalf of child.  NB: child is usually going to be a
197  * child of one of our descendants, not a direct child of nexus0.
198  * (Exceptions include footbridge.)
199  */
200 static struct resource *
201 nexus_alloc_resource(device_t bus, device_t child, int type, int *rid,
202     u_long start, u_long end, u_long count, u_int flags)
203 {
204 	struct nexus_device *ndev = DEVTONX(child);
205 	struct resource *rv;
206 	struct resource_list_entry *rle;
207 	struct rman *rm;
208 	int needactivate = flags & RF_ACTIVE;
209 
210 	/*
211 	 * If this is an allocation of the "default" range for a given
212 	 * RID, and we know what the resources for this device are
213 	 * (ie. they aren't maintained by a child bus), then work out
214 	 * the start/end values.
215 	 */
216 	if (RMAN_IS_DEFAULT_RANGE(start, end) && (count == 1)) {
217 		if (device_get_parent(child) != bus || ndev == NULL)
218 			return(NULL);
219 		rle = resource_list_find(&ndev->nx_resources, type, *rid);
220 		if (rle == NULL)
221 			return(NULL);
222 		start = rle->start;
223 		end = rle->end;
224 		count = rle->count;
225 	}
226 
227 	switch (type) {
228 	case SYS_RES_IRQ:
229 		rm = &irq_rman;
230 		break;
231 
232 	case SYS_RES_MEMORY:
233 	case SYS_RES_IOPORT:
234 		rm = &mem_rman;
235 		break;
236 
237 	default:
238 		return (NULL);
239 	}
240 
241 	rv = rman_reserve_resource(rm, start, end, count, flags, child);
242 	if (rv == NULL)
243 		return (NULL);
244 
245 	rman_set_rid(rv, *rid);
246 	rman_set_bushandle(rv, rman_get_start(rv));
247 
248 	if (needactivate) {
249 		if (bus_activate_resource(child, type, *rid, rv)) {
250 			rman_release_resource(rv);
251 			return (NULL);
252 		}
253 	}
254 
255 	return (rv);
256 }
257 
258 static int
259 nexus_config_intr(device_t dev, int irq, enum intr_trigger trig,
260     enum intr_polarity pol)
261 {
262 
263 	return (EOPNOTSUPP);
264 }
265 
266 static int
267 nexus_setup_intr(device_t dev, device_t child, struct resource *res, int flags,
268     driver_filter_t *filt, driver_intr_t *intr, void *arg, void **cookiep)
269 {
270 	int error;
271 
272 	if ((rman_get_flags(res) & RF_SHAREABLE) == 0)
273 		flags |= INTR_EXCL;
274 
275 	/* We depend here on rman_activate_resource() being idempotent. */
276 	error = rman_activate_resource(res);
277 	if (error)
278 		return (error);
279 
280 	error = intr_setup_irq(child, res, filt, intr, arg, flags, cookiep);
281 
282 	return (error);
283 }
284 
285 static int
286 nexus_teardown_intr(device_t dev, device_t child, struct resource *r, void *ih)
287 {
288 
289 	return (intr_teardown_irq(child, r, ih));
290 }
291 
292 static int
293 nexus_activate_resource(device_t bus, device_t child, int type, int rid,
294     struct resource *r)
295 {
296 	int err;
297 	bus_addr_t paddr;
298 	bus_size_t psize;
299 	bus_space_handle_t vaddr;
300 
301 	if ((err = rman_activate_resource(r)) != 0)
302 		return (err);
303 
304 	/*
305 	 * If this is a memory resource, map it into the kernel.
306 	 */
307 	if (type == SYS_RES_MEMORY || type == SYS_RES_IOPORT) {
308 		paddr = (bus_addr_t)rman_get_start(r);
309 		psize = (bus_size_t)rman_get_size(r);
310 		err = bus_space_map(&memmap_bus, paddr, psize, 0, &vaddr);
311 		if (err != 0) {
312 			rman_deactivate_resource(r);
313 			return (err);
314 		}
315 		rman_set_bustag(r, &memmap_bus);
316 		rman_set_virtual(r, (void *)vaddr);
317 		rman_set_bushandle(r, vaddr);
318 	} else if (type == SYS_RES_IRQ) {
319 		err = intr_activate_irq(child, r);
320 		if (err != 0) {
321 			rman_deactivate_resource(r);
322 			return (err);
323 		}
324 	}
325 
326 	return (0);
327 }
328 
329 static struct resource_list *
330 nexus_get_reslist(device_t dev, device_t child)
331 {
332 	struct nexus_device *ndev = DEVTONX(child);
333 
334 	return (&ndev->nx_resources);
335 }
336 
337 static int
338 nexus_set_resource(device_t dev, device_t child, int type, int rid,
339     u_long start, u_long count)
340 {
341 	struct nexus_device	*ndev = DEVTONX(child);
342 	struct resource_list	*rl = &ndev->nx_resources;
343 
344 	/* XXX this should return a success/failure indicator */
345 	resource_list_add(rl, type, rid, start, start + count - 1, count);
346 
347 	return(0);
348 }
349 
350 static int
351 nexus_deactivate_resource(device_t bus, device_t child, int type, int rid,
352     struct resource *r)
353 {
354 	bus_size_t psize;
355 	bus_space_handle_t vaddr;
356 
357 	if (type == SYS_RES_MEMORY || type == SYS_RES_IOPORT) {
358 		psize = (bus_size_t)rman_get_size(r);
359 		vaddr = rman_get_bushandle(r);
360 
361 		if (vaddr != 0) {
362 			bus_space_unmap(&memmap_bus, vaddr, psize);
363 			rman_set_virtual(r, NULL);
364 			rman_set_bushandle(r, 0);
365 		}
366 	} else if (type == SYS_RES_IRQ) {
367 		intr_deactivate_irq(child, r);
368 	}
369 
370 	return (rman_deactivate_resource(r));
371 }
372 
373 static devclass_t nexus_fdt_devclass;
374 
375 EARLY_DRIVER_MODULE(nexus_fdt, root, nexus_fdt_driver, nexus_fdt_devclass,
376     0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_FIRST);
377 
378 static int
379 nexus_ofw_map_intr(device_t dev, device_t child, phandle_t iparent, int icells,
380     pcell_t *intr)
381 {
382 	struct intr_map_data_fdt *fdt_data;
383 	size_t len;
384 	u_int irq;
385 
386 	len = sizeof(*fdt_data) + icells * sizeof(pcell_t);
387 	fdt_data = (struct intr_map_data_fdt *)intr_alloc_map_data(
388 	    INTR_MAP_DATA_FDT, len, M_WAITOK | M_ZERO);
389 	fdt_data->iparent = iparent;
390 	fdt_data->ncells = icells;
391 	memcpy(fdt_data->cells, intr, icells * sizeof(pcell_t));
392 	irq = intr_map_irq(NULL, iparent, (struct intr_map_data *)fdt_data);
393 
394 	return (irq);
395 }
396