xref: /netbsd-src/sys/arch/arm/fdt/gic_fdt.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: gic_fdt.c,v 1.12 2018/07/15 13:34:43 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2015-2017 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: gic_fdt.c,v 1.12 2018/07/15 13:34:43 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/lwp.h>
39 #include <sys/kmem.h>
40 #include <sys/queue.h>
41 
42 #include <arm/cortex/gic_intr.h>
43 #include <arm/cortex/mpcore_var.h>
44 
45 #include <dev/fdt/fdtvar.h>
46 
47 #define	GIC_MAXIRQ	1020
48 
49 static int	gic_fdt_match(device_t, cfdata_t, void *);
50 static void	gic_fdt_attach(device_t, device_t, void *);
51 
52 static int	gic_fdt_intr(void *);
53 
54 static void *	gic_fdt_establish(device_t, u_int *, int, int,
55 		    int (*)(void *), void *);
56 static void	gic_fdt_disestablish(device_t, void *);
57 static bool	gic_fdt_intrstr(device_t, u_int *, char *, size_t);
58 
59 struct fdtbus_interrupt_controller_func gic_fdt_funcs = {
60 	.establish = gic_fdt_establish,
61 	.disestablish = gic_fdt_disestablish,
62 	.intrstr = gic_fdt_intrstr
63 };
64 
65 struct gic_fdt_softc;
66 struct gic_fdt_irq;
67 
68 struct gic_fdt_irqhandler {
69 	struct gic_fdt_irq	*ih_irq;
70 	int			(*ih_fn)(void *);
71 	void			*ih_arg;
72 	bool			ih_mpsafe;
73 	TAILQ_ENTRY(gic_fdt_irqhandler) ih_next;
74 };
75 
76 struct gic_fdt_irq {
77 	struct gic_fdt_softc	*intr_sc;
78 	void			*intr_ih;
79 	void			*intr_arg;
80 	int			intr_refcnt;
81 	int			intr_ipl;
82 	int			intr_level;
83 	int			intr_mpsafe;
84 	TAILQ_HEAD(, gic_fdt_irqhandler) intr_handlers;
85 	int			intr_irq;
86 };
87 
88 struct gic_fdt_softc {
89 	device_t		sc_dev;
90 	int			sc_phandle;
91 
92 	struct gic_fdt_irq	*sc_irq[GIC_MAXIRQ];
93 };
94 
95 CFATTACH_DECL_NEW(gic_fdt, sizeof(struct gic_fdt_softc),
96 	gic_fdt_match, gic_fdt_attach, NULL, NULL);
97 
98 static int
99 gic_fdt_match(device_t parent, cfdata_t cf, void *aux)
100 {
101 	const char * const compatible[] = {
102 		"arm,gic-400",
103 		"arm,cortex-a15-gic",
104 		"arm,cortex-a9-gic",
105 		"arm,cortex-a7-gic",
106 		NULL
107 	};
108 	struct fdt_attach_args * const faa = aux;
109 
110 	return of_compatible(faa->faa_phandle, compatible) >= 0;
111 }
112 
113 static void
114 gic_fdt_attach(device_t parent, device_t self, void *aux)
115 {
116 	struct gic_fdt_softc * const sc = device_private(self);
117 	struct fdt_attach_args * const faa = aux;
118 	bus_addr_t addr_d, addr_c;
119 	bus_size_t size_d, size_c;
120 	bus_space_handle_t bsh;
121 	int error;
122 
123 	sc->sc_dev = self;
124 	sc->sc_phandle = faa->faa_phandle;
125 
126 	error = fdtbus_register_interrupt_controller(self, faa->faa_phandle,
127 	    &gic_fdt_funcs);
128 	if (error) {
129 		aprint_error(": couldn't register with fdtbus: %d\n", error);
130 		return;
131 	}
132 
133 	aprint_naive("\n");
134 	aprint_normal(": GIC\n");
135 
136 	if (fdtbus_get_reg(sc->sc_phandle, 0, &addr_d, &size_d) != 0) {
137 		aprint_error(": couldn't get distributor address\n");
138 		return;
139 	}
140 	if (fdtbus_get_reg(sc->sc_phandle, 1, &addr_c, &size_c) != 0) {
141 		aprint_error(": couldn't get cpu interface address\n");
142 		return;
143 	}
144 
145 	const bus_addr_t addr = min(addr_d, addr_c);
146 	const bus_size_t end = max(addr_d + size_d, addr_c + size_c);
147 	const bus_size_t size = end - addr;
148 
149 	error = bus_space_map(faa->faa_bst, addr, size, 0, &bsh);
150 	if (error) {
151 		aprint_error(": couldn't map registers: %d\n", error);
152 		return;
153 	}
154 
155 	struct mpcore_attach_args mpcaa = {
156 		.mpcaa_name = "armgic",
157 		.mpcaa_memt = faa->faa_bst,
158 		.mpcaa_memh = bsh,
159 		.mpcaa_off1 = addr_d - addr,
160 		.mpcaa_off2 = addr_c - addr,
161 	};
162 
163 	config_found(self, &mpcaa, NULL);
164 
165 	arm_fdt_irq_set_handler(armgic_irq_handler);
166 }
167 
168 static void *
169 gic_fdt_establish(device_t dev, u_int *specifier, int ipl, int flags,
170     int (*func)(void *), void *arg)
171 {
172 	struct gic_fdt_softc * const sc = device_private(dev);
173 	struct gic_fdt_irq *firq;
174 	struct gic_fdt_irqhandler *firqh;
175 
176 	/* 1st cell is the interrupt type; 0 is SPI, 1 is PPI */
177 	/* 2nd cell is the interrupt number */
178 	/* 3rd cell is flags */
179 
180 	const u_int type = be32toh(specifier[0]);
181 	const u_int intr = be32toh(specifier[1]);
182 	const u_int irq = type == 0 ? IRQ_SPI(intr) : IRQ_PPI(intr);
183 	const u_int trig = be32toh(specifier[2]) & 0xf;
184 	const u_int level = (trig & 0x3) ? IST_EDGE : IST_LEVEL;
185 
186 	const u_int mpsafe = (flags & FDT_INTR_MPSAFE) ? IST_MPSAFE : 0;
187 
188 	firq = sc->sc_irq[irq];
189 	if (firq == NULL) {
190 		firq = kmem_alloc(sizeof(*firq), KM_SLEEP);
191 		firq->intr_sc = sc;
192 		firq->intr_refcnt = 0;
193 		firq->intr_arg = arg;
194 		firq->intr_ipl = ipl;
195 		firq->intr_level = level;
196 		firq->intr_mpsafe = mpsafe;
197 		TAILQ_INIT(&firq->intr_handlers);
198 		firq->intr_irq = irq;
199 		if (arg == NULL) {
200 			firq->intr_ih = intr_establish(irq, ipl, level | mpsafe,
201 			    func, NULL);
202 		} else {
203 			firq->intr_ih = intr_establish(irq, ipl, level | mpsafe,
204 			    gic_fdt_intr, firq);
205 		}
206 		if (firq->intr_ih == NULL) {
207 			kmem_free(firq, sizeof(*firq));
208 			return NULL;
209 		}
210 		sc->sc_irq[irq] = firq;
211 	} else {
212 		if (firq->intr_arg == NULL && arg != NULL) {
213 			device_printf(dev, "cannot share irq with NULL arg\n");
214 			return NULL;
215 		}
216 		if (firq->intr_ipl != ipl) {
217 			device_printf(dev, "cannot share irq with different "
218 			    "ipl\n");
219 			return NULL;
220 		}
221 		if (firq->intr_level != level) {
222 			device_printf(dev, "cannot share edge and level "
223 			    "interrupts\n");
224 			return NULL;
225 		}
226 		if (firq->intr_mpsafe != mpsafe) {
227 			device_printf(dev, "cannot share between "
228 			    "mpsafe/non-mpsafe\n");
229 			return NULL;
230 		}
231 	}
232 
233 	firq->intr_refcnt++;
234 
235 	firqh = kmem_alloc(sizeof(*firqh), KM_SLEEP);
236 	firqh->ih_mpsafe = (flags & FDT_INTR_MPSAFE) != 0;
237 	firqh->ih_irq = firq;
238 	firqh->ih_fn = func;
239 	firqh->ih_arg = arg;
240 	TAILQ_INSERT_TAIL(&firq->intr_handlers, firqh, ih_next);
241 
242 	return firq->intr_ih;
243 }
244 
245 static void
246 gic_fdt_disestablish(device_t dev, void *ih)
247 {
248 	struct gic_fdt_softc * const sc = device_private(dev);
249 	struct gic_fdt_irqhandler *firqh;
250 	struct gic_fdt_irq *firq;
251 	u_int n;
252 
253 	for (n = 0; n < GIC_MAXIRQ; n++) {
254 		firq = sc->sc_irq[n];
255 		if (firq->intr_ih != ih)
256 			continue;
257 
258 		KASSERT(firq->intr_refcnt > 0);
259 
260 		if (firq->intr_refcnt > 1)
261 			panic("%s: cannot disestablish shared irq", __func__);
262 
263 		firqh = TAILQ_FIRST(&firq->intr_handlers);
264 		kmem_free(firqh, sizeof(*firqh));
265 		intr_disestablish(firq->intr_ih);
266 		kmem_free(firq, sizeof(*firq));
267 		sc->sc_irq[n] = NULL;
268 		return;
269 	}
270 
271 	panic("%s: interrupt not established", __func__);
272 }
273 
274 static int
275 gic_fdt_intr(void *priv)
276 {
277 	struct gic_fdt_irq *firq = priv;
278 	struct gic_fdt_irqhandler *firqh;
279 	int handled = 0;
280 
281 	TAILQ_FOREACH(firqh, &firq->intr_handlers, ih_next)
282 		handled += firqh->ih_fn(firqh->ih_arg);
283 
284 	return handled;
285 }
286 
287 static bool
288 gic_fdt_intrstr(device_t dev, u_int *specifier, char *buf, size_t buflen)
289 {
290 	/* 1st cell is the interrupt type; 0 is SPI, 1 is PPI */
291 	/* 2nd cell is the interrupt number */
292 	/* 3rd cell is flags */
293 
294 	if (!specifier)
295 		return false;
296 	const u_int type = be32toh(specifier[0]);
297 	const u_int intr = be32toh(specifier[1]);
298 	const u_int irq = type == 0 ? IRQ_SPI(intr) : IRQ_PPI(intr);
299 
300 	snprintf(buf, buflen, "GIC irq %d", irq);
301 
302 	return true;
303 }
304