xref: /netbsd-src/sys/arch/arm/fdt/gic_fdt.c (revision c38e7cc395b1472a774ff828e46123de44c628e9)
1 /* $NetBSD: gic_fdt.c,v 1.8 2017/11/30 14:42:37 skrll 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 1.8 2017/11/30 14:42:37 skrll 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 
41 #include <arm/cortex/gic_intr.h>
42 #include <arm/cortex/mpcore_var.h>
43 
44 #include <dev/fdt/fdtvar.h>
45 
46 #define	GIC_MAXIRQ	1020
47 
48 static int	gic_fdt_match(device_t, cfdata_t, void *);
49 static void	gic_fdt_attach(device_t, device_t, void *);
50 
51 static int	gic_fdt_intr(void *);
52 
53 static void *	gic_fdt_establish(device_t, u_int *, int, int,
54 		    int (*)(void *), void *);
55 static void	gic_fdt_disestablish(device_t, void *);
56 static bool	gic_fdt_intrstr(device_t, u_int *, char *, size_t);
57 
58 struct fdtbus_interrupt_controller_func gic_fdt_funcs = {
59 	.establish = gic_fdt_establish,
60 	.disestablish = gic_fdt_disestablish,
61 	.intrstr = gic_fdt_intrstr
62 };
63 
64 struct gic_fdt_softc;
65 struct gic_fdt_irq;
66 
67 struct gic_fdt_irqhandler {
68 	struct gic_fdt_irq	*ih_irq;
69 	int			(*ih_fn)(void *);
70 	void			*ih_arg;
71 	bool			ih_mpsafe;
72 	TAILQ_ENTRY(gic_fdt_irqhandler) ih_next;
73 };
74 
75 struct gic_fdt_irq {
76 	struct gic_fdt_softc	*intr_sc;
77 	void			*intr_ih;
78 	int			intr_refcnt;
79 	int			intr_ipl;
80 	int			intr_level;
81 	int			intr_mpsafe;
82 	TAILQ_HEAD(, gic_fdt_irqhandler) intr_handlers;
83 };
84 
85 struct gic_fdt_softc {
86 	device_t		sc_dev;
87 	int			sc_phandle;
88 
89 	struct gic_fdt_irq	*sc_irq[GIC_MAXIRQ];
90 };
91 
92 CFATTACH_DECL_NEW(gic_fdt, sizeof(struct gic_fdt_softc),
93 	gic_fdt_match, gic_fdt_attach, NULL, NULL);
94 
95 static int
96 gic_fdt_match(device_t parent, cfdata_t cf, void *aux)
97 {
98 	const char * const compatible[] = {
99 		"arm,gic-400",
100 		"arm,cortex-a15-gic",
101 		"arm,cortex-a9-gic",
102 		"arm,cortex-a7-gic",
103 		NULL
104 	};
105 	struct fdt_attach_args * const faa = aux;
106 
107 	return of_compatible(faa->faa_phandle, compatible) >= 0;
108 }
109 
110 static void
111 gic_fdt_attach(device_t parent, device_t self, void *aux)
112 {
113 	struct gic_fdt_softc * const sc = device_private(self);
114 	struct fdt_attach_args * const faa = aux;
115 	bus_addr_t addr_d, addr_c;
116 	bus_size_t size_d, size_c;
117 	bus_space_handle_t bsh;
118 	int error;
119 
120 	sc->sc_dev = self;
121 	sc->sc_phandle = faa->faa_phandle;
122 
123 	error = fdtbus_register_interrupt_controller(self, faa->faa_phandle,
124 	    &gic_fdt_funcs);
125 	if (error) {
126 		aprint_error(": couldn't register with fdtbus: %d\n", error);
127 		return;
128 	}
129 
130 	aprint_naive("\n");
131 	aprint_normal(": GIC\n");
132 
133 	if (fdtbus_get_reg(sc->sc_phandle, 0, &addr_d, &size_d) != 0) {
134 		aprint_error(": couldn't get distributor address\n");
135 		return;
136 	}
137 	if (fdtbus_get_reg(sc->sc_phandle, 1, &addr_c, &size_c) != 0) {
138 		aprint_error(": couldn't get cpu interface address\n");
139 		return;
140 	}
141 
142 	const bus_addr_t addr = addr_d;
143 	const bus_size_t size = (addr_c + size_c) - addr_d;
144 
145 	error = bus_space_map(faa->faa_bst, addr, size, 0, &bsh);
146 	if (error) {
147 		aprint_error(": couldn't map registers: %d\n", error);
148 		return;
149 	}
150 
151 	struct mpcore_attach_args mpcaa = {
152 		.mpcaa_name = "armgic",
153 		.mpcaa_memt = faa->faa_bst,
154 		.mpcaa_memh = bsh,
155 		.mpcaa_off1 = 0,
156 		.mpcaa_off2 = addr_c - addr_d
157 	};
158 
159 	config_found(self, &mpcaa, NULL);
160 
161 	arm_fdt_irq_set_handler(armgic_irq_handler);
162 }
163 
164 static void *
165 gic_fdt_establish(device_t dev, u_int *specifier, int ipl, int flags,
166     int (*func)(void *), void *arg)
167 {
168 	struct gic_fdt_softc * const sc = device_private(dev);
169 	struct gic_fdt_irq *firq;
170 	struct gic_fdt_irqhandler *firqh;
171 
172 	/* 1st cell is the interrupt type; 0 is SPI, 1 is PPI */
173 	/* 2nd cell is the interrupt number */
174 	/* 3rd cell is flags */
175 
176 	const u_int type = be32toh(specifier[0]);
177 	const u_int intr = be32toh(specifier[1]);
178 	const u_int irq = type == 0 ? IRQ_SPI(intr) : IRQ_PPI(intr);
179 	const u_int trig = be32toh(specifier[2]) & 0xf;
180 	const u_int level = (trig & 0x3) ? IST_EDGE : IST_LEVEL;
181 
182 	const u_int mpsafe = (flags & FDT_INTR_MPSAFE) ? IST_MPSAFE : 0;
183 
184 	firq = sc->sc_irq[irq];
185 	if (firq == NULL) {
186 		firq = kmem_alloc(sizeof(*firq), KM_SLEEP);
187 		firq->intr_sc = sc;
188 		firq->intr_refcnt = 0;
189 		firq->intr_ipl = ipl;
190 		firq->intr_level = level;
191 		firq->intr_mpsafe = mpsafe;
192 		TAILQ_INIT(&firq->intr_handlers);
193 		if (arg == NULL) {
194 			firq->intr_ih = intr_establish(irq, ipl, level | mpsafe,
195 			    func, NULL);
196 		} else {
197 			firq->intr_ih = intr_establish(irq, ipl, level | mpsafe,
198 			    gic_fdt_intr, firq);
199 		}
200 		if (firq->intr_ih == NULL) {
201 			kmem_free(firq, sizeof(*firq));
202 			return NULL;
203 		}
204 		sc->sc_irq[irq] = firq;
205 	} else {
206 		if (arg) {
207 			device_printf(dev, "cannot share irq with NULL arg\n");
208 			return NULL;
209 		}
210 		if (firq->intr_ipl != ipl) {
211 			device_printf(dev, "cannot share irq with different "
212 			    "ipl\n");
213 			return NULL;
214 		}
215 		if (firq->intr_level != level) {
216 			device_printf(dev, "cannot share edge and level "
217 			    "interrupts\n");
218 			return NULL;
219 		}
220 		if (firq->intr_mpsafe != mpsafe) {
221 			device_printf(dev, "cannot share between "
222 			    "mpsafe/non-mpsafe\n");
223 			return NULL;
224 		}
225 	}
226 
227 	firq->intr_refcnt++;
228 
229 	firqh = kmem_alloc(sizeof(*firqh), KM_SLEEP);
230 	firqh->ih_mpsafe = (flags & FDT_INTR_MPSAFE) != 0;
231 	firqh->ih_irq = firq;
232 	firqh->ih_fn = func;
233 	firqh->ih_arg = arg;
234 	TAILQ_INSERT_TAIL(&firq->intr_handlers, firqh, ih_next);
235 
236 	return firqh;
237 }
238 
239 static void
240 gic_fdt_disestablish(device_t dev, void *ih)
241 {
242 	struct gic_fdt_irqhandler *firqh = ih;
243 	struct gic_fdt_irq *firq = firqh->ih_irq;
244 
245 	KASSERT(firq->intr_refcnt > 0);
246 
247 	TAILQ_REMOVE(&firq->intr_handlers, firqh, ih_next);
248 	kmem_free(firqh, sizeof(*firqh));
249 
250 	firq->intr_refcnt--;
251 	if (firq->intr_refcnt == 0) {
252 		intr_disestablish(firq->intr_ih);
253 		kmem_free(firq, sizeof(*firq));
254 	}
255 }
256 
257 static int
258 gic_fdt_intr(void *priv)
259 {
260 	struct gic_fdt_irq *firq = priv;
261 	struct gic_fdt_irqhandler *firqh;
262 	int handled = 0;
263 
264 	TAILQ_FOREACH(firqh, &firq->intr_handlers, ih_next)
265 		handled += firqh->ih_fn(firqh->ih_arg);
266 
267 	return handled;
268 }
269 
270 static bool
271 gic_fdt_intrstr(device_t dev, u_int *specifier, char *buf, size_t buflen)
272 {
273 	/* 1st cell is the interrupt type; 0 is SPI, 1 is PPI */
274 	/* 2nd cell is the interrupt number */
275 	/* 3rd cell is flags */
276 
277 	if (!specifier)
278 		return false;
279 	const u_int type = be32toh(specifier[0]);
280 	const u_int intr = be32toh(specifier[1]);
281 	const u_int irq = type == 0 ? IRQ_SPI(intr) : IRQ_PPI(intr);
282 
283 	snprintf(buf, buflen, "GIC irq %d", irq);
284 
285 	return true;
286 }
287