xref: /freebsd/sys/powerpc/pseries/xics.c (revision d06955f9bdb1416d9196043ed781f9b36dae9adc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright 2011 Nathan Whitehorn
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/module.h>
34 #include <sys/bus.h>
35 #include <sys/conf.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/smp.h>
39 
40 #include <vm/vm.h>
41 #include <vm/pmap.h>
42 
43 #include <machine/bus.h>
44 #include <machine/intr_machdep.h>
45 #include <machine/md_var.h>
46 #include <machine/rtas.h>
47 
48 #include <dev/ofw/ofw_bus.h>
49 #include <dev/ofw/ofw_bus_subr.h>
50 
51 #include "phyp-hvcall.h"
52 #include "pic_if.h"
53 
54 #define XICP_PRIORITY	5	/* Random non-zero number */
55 #define XICP_IPI	2
56 #define MAX_XICP_IRQS	(1<<24)	/* 24-bit XIRR field */
57 
58 static int	xicp_probe(device_t);
59 static int	xicp_attach(device_t);
60 static int	xics_probe(device_t);
61 static int	xics_attach(device_t);
62 
63 static void	xicp_bind(device_t dev, u_int irq, cpuset_t cpumask);
64 static void	xicp_dispatch(device_t, struct trapframe *);
65 static void	xicp_enable(device_t, u_int, u_int);
66 static void	xicp_eoi(device_t, u_int);
67 static void	xicp_ipi(device_t, u_int);
68 static void	xicp_mask(device_t, u_int);
69 static void	xicp_unmask(device_t, u_int);
70 
71 static device_method_t  xicp_methods[] = {
72 	/* Device interface */
73 	DEVMETHOD(device_probe,		xicp_probe),
74 	DEVMETHOD(device_attach,	xicp_attach),
75 
76 	/* PIC interface */
77 	DEVMETHOD(pic_bind,		xicp_bind),
78 	DEVMETHOD(pic_dispatch,		xicp_dispatch),
79 	DEVMETHOD(pic_enable,		xicp_enable),
80 	DEVMETHOD(pic_eoi,		xicp_eoi),
81 	DEVMETHOD(pic_ipi,		xicp_ipi),
82 	DEVMETHOD(pic_mask,		xicp_mask),
83 	DEVMETHOD(pic_unmask,		xicp_unmask),
84 
85 	{ 0, 0 },
86 };
87 
88 static device_method_t  xics_methods[] = {
89 	/* Device interface */
90 	DEVMETHOD(device_probe,		xics_probe),
91 	DEVMETHOD(device_attach,	xics_attach),
92 
93 	{ 0, 0 },
94 };
95 
96 struct xicp_softc {
97 	struct mtx sc_mtx;
98 
99 	int ibm_int_on;
100 	int ibm_int_off;
101 	int ibm_get_xive;
102 	int ibm_set_xive;
103 
104 	/* XXX: inefficient -- hash table? tree? */
105 	struct {
106 		int irq;
107 		int vector;
108 	} intvecs[256];
109 	int nintvecs;
110 };
111 
112 static driver_t xicp_driver = {
113 	"xicp",
114 	xicp_methods,
115 	sizeof(struct xicp_softc)
116 };
117 
118 static driver_t xics_driver = {
119 	"xics",
120 	xics_methods,
121 	0
122 };
123 
124 static devclass_t xicp_devclass;
125 static devclass_t xics_devclass;
126 
127 EARLY_DRIVER_MODULE(xicp, ofwbus, xicp_driver, xicp_devclass, 0, 0,
128     BUS_PASS_INTERRUPT-1);
129 EARLY_DRIVER_MODULE(xics, ofwbus, xics_driver, xics_devclass, 0, 0,
130     BUS_PASS_INTERRUPT);
131 
132 static int
133 xicp_probe(device_t dev)
134 {
135 	if (ofw_bus_get_name(dev) == NULL || strcmp(ofw_bus_get_name(dev),
136 	    "interrupt-controller") != 0)
137 		return (ENXIO);
138 
139 	if (!ofw_bus_is_compatible(dev, "ibm,ppc-xicp"))
140 		return (ENXIO);
141 
142 	device_set_desc(dev, "PAPR virtual interrupt controller");
143 	return (BUS_PROBE_GENERIC);
144 }
145 
146 static int
147 xics_probe(device_t dev)
148 {
149 	if (ofw_bus_get_name(dev) == NULL || strcmp(ofw_bus_get_name(dev),
150 	    "interrupt-controller") != 0)
151 		return (ENXIO);
152 
153 	if (!ofw_bus_is_compatible(dev, "ibm,ppc-xics"))
154 		return (ENXIO);
155 
156 	device_set_desc(dev, "PAPR virtual interrupt source");
157 	return (BUS_PROBE_GENERIC);
158 }
159 
160 static int
161 xicp_attach(device_t dev)
162 {
163 	struct xicp_softc *sc = device_get_softc(dev);
164 	phandle_t phandle = ofw_bus_get_node(dev);
165 
166 	mtx_init(&sc->sc_mtx, "XICP", NULL, MTX_DEF);
167 	sc->nintvecs = 0;
168 
169 	sc->ibm_int_on = rtas_token_lookup("ibm,int-on");
170 	sc->ibm_int_off = rtas_token_lookup("ibm,int-off");
171 	sc->ibm_set_xive = rtas_token_lookup("ibm,set-xive");
172 	sc->ibm_get_xive = rtas_token_lookup("ibm,get-xive");
173 
174 	powerpc_register_pic(dev, OF_xref_from_node(phandle), MAX_XICP_IRQS,
175 	    1 /* Number of IPIs */, FALSE);
176 	root_pic = dev;
177 
178 	return (0);
179 }
180 
181 static int
182 xics_attach(device_t dev)
183 {
184 	phandle_t phandle = ofw_bus_get_node(dev);
185 
186 	/* The XICP (root PIC) will handle all our interrupts */
187 	powerpc_register_pic(root_pic, OF_xref_from_node(phandle),
188 	    MAX_XICP_IRQS, 1 /* Number of IPIs */, FALSE);
189 
190 	return (0);
191 }
192 
193 /*
194  * PIC I/F methods.
195  */
196 
197 static void
198 xicp_bind(device_t dev, u_int irq, cpuset_t cpumask)
199 {
200 	struct xicp_softc *sc = device_get_softc(dev);
201 	cell_t status, cpu;
202 	int ncpus, i, error;
203 
204 	/*
205 	 * This doesn't appear to actually support affinity groups, so pick a
206 	 * random CPU.
207 	 */
208 	ncpus = 0;
209 	CPU_FOREACH(cpu)
210 		if (CPU_ISSET(cpu, &cpumask)) ncpus++;
211 
212 	i = mftb() % ncpus;
213 	ncpus = 0;
214 	CPU_FOREACH(cpu) {
215 		if (!CPU_ISSET(cpu, &cpumask))
216 			continue;
217 		if (ncpus == i)
218 			break;
219 		ncpus++;
220 	}
221 
222 
223 	error = rtas_call_method(sc->ibm_set_xive, 3, 1, irq, cpu,
224 	    XICP_PRIORITY, &status);
225 	if (error < 0)
226 		panic("Cannot bind interrupt %d to CPU %d", irq, cpu);
227 }
228 
229 static void
230 xicp_dispatch(device_t dev, struct trapframe *tf)
231 {
232 	struct xicp_softc *sc;
233 	uint64_t xirr, junk;
234 	int i;
235 
236 	sc = device_get_softc(dev);
237 	for (;;) {
238 		/* Return value in R4, use the PFT call */
239 		phyp_pft_hcall(H_XIRR, 0, 0, 0, 0, &xirr, &junk, &junk);
240 		xirr &= 0x00ffffff;
241 
242 		if (xirr == 0) { /* No more pending interrupts? */
243 			phyp_hcall(H_CPPR, (uint64_t)0xff);
244 			break;
245 		}
246 		if (xirr == XICP_IPI) {		/* Magic number for IPIs */
247 			xirr = MAX_XICP_IRQS;	/* Map to FreeBSD magic */
248 			phyp_hcall(H_IPI, (uint64_t)(PCPU_GET(cpuid)),
249 			    0xff); /* Clear IPI */
250 		}
251 
252 		/* XXX: super inefficient */
253 		for (i = 0; i < sc->nintvecs; i++) {
254 			if (sc->intvecs[i].irq == xirr)
255 				break;
256 		}
257 
258 		KASSERT(i < sc->nintvecs, ("Unmapped XIRR"));
259 		powerpc_dispatch_intr(sc->intvecs[i].vector, tf);
260 	}
261 }
262 
263 static void
264 xicp_enable(device_t dev, u_int irq, u_int vector)
265 {
266 	struct xicp_softc *sc;
267 	cell_t status, cpu;
268 
269 	sc = device_get_softc(dev);
270 
271 	KASSERT(sc->nintvecs + 1 < nitems(sc->intvecs),
272 		("Too many XICP interrupts"));
273 
274 	mtx_lock(&sc->sc_mtx);
275 	sc->intvecs[sc->nintvecs].irq = irq;
276 	sc->intvecs[sc->nintvecs].vector = vector;
277 	mb();
278 	sc->nintvecs++;
279 	mtx_unlock(&sc->sc_mtx);
280 
281 	/* IPIs are also enabled */
282 	if (irq == MAX_XICP_IRQS)
283 		return;
284 
285 	/* Bind to this CPU to start: distrib. ID is last entry in gserver# */
286 	cpu = PCPU_GET(cpuid);
287 	rtas_call_method(sc->ibm_set_xive, 3, 1, irq, cpu, XICP_PRIORITY,
288 	    &status);
289 	xicp_unmask(dev, irq);
290 }
291 
292 static void
293 xicp_eoi(device_t dev, u_int irq)
294 {
295 	uint64_t xirr;
296 
297 	if (irq == MAX_XICP_IRQS) /* Remap IPI interrupt to internal value */
298 		irq = XICP_IPI;
299 	xirr = irq | (XICP_PRIORITY << 24);
300 
301 	phyp_hcall(H_EOI, xirr);
302 }
303 
304 static void
305 xicp_ipi(device_t dev, u_int cpu)
306 {
307 
308 	phyp_hcall(H_IPI, (uint64_t)cpu, XICP_PRIORITY);
309 }
310 
311 static void
312 xicp_mask(device_t dev, u_int irq)
313 {
314 	struct xicp_softc *sc = device_get_softc(dev);
315 	cell_t status;
316 
317 	if (irq == MAX_XICP_IRQS)
318 		return;
319 
320 	rtas_call_method(sc->ibm_int_off, 1, 1, irq, &status);
321 }
322 
323 static void
324 xicp_unmask(device_t dev, u_int irq)
325 {
326 	struct xicp_softc *sc = device_get_softc(dev);
327 	cell_t status;
328 
329 	if (irq == MAX_XICP_IRQS)
330 		return;
331 
332 	rtas_call_method(sc->ibm_int_on, 1, 1, irq, &status);
333 }
334 
335