xref: /freebsd/sys/powerpc/pseries/xics.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*-
2  * Copyright 2011 Nathan Whitehorn
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
18  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
20  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
21  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/module.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/smp.h>
37 
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 
41 #include <machine/bus.h>
42 #include <machine/intr_machdep.h>
43 #include <machine/md_var.h>
44 #include <machine/rtas.h>
45 
46 #include <dev/ofw/ofw_bus.h>
47 #include <dev/ofw/ofw_bus_subr.h>
48 
49 #include "phyp-hvcall.h"
50 #include "pic_if.h"
51 
52 #define XICP_PRIORITY	5	/* Random non-zero number */
53 #define XICP_IPI	2
54 #define MAX_XICP_IRQS	(1<<24)	/* 24-bit XIRR field */
55 
56 static int	xicp_probe(device_t);
57 static int	xicp_attach(device_t);
58 static int	xics_probe(device_t);
59 static int	xics_attach(device_t);
60 
61 static void	xicp_bind(device_t dev, u_int irq, cpuset_t cpumask);
62 static void	xicp_dispatch(device_t, struct trapframe *);
63 static void	xicp_enable(device_t, u_int, u_int);
64 static void	xicp_eoi(device_t, u_int);
65 static void	xicp_ipi(device_t, u_int);
66 static void	xicp_mask(device_t, u_int);
67 static void	xicp_unmask(device_t, u_int);
68 
69 static device_method_t  xicp_methods[] = {
70 	/* Device interface */
71 	DEVMETHOD(device_probe,		xicp_probe),
72 	DEVMETHOD(device_attach,	xicp_attach),
73 
74 	/* PIC interface */
75 	DEVMETHOD(pic_bind,		xicp_bind),
76 	DEVMETHOD(pic_dispatch,		xicp_dispatch),
77 	DEVMETHOD(pic_enable,		xicp_enable),
78 	DEVMETHOD(pic_eoi,		xicp_eoi),
79 	DEVMETHOD(pic_ipi,		xicp_ipi),
80 	DEVMETHOD(pic_mask,		xicp_mask),
81 	DEVMETHOD(pic_unmask,		xicp_unmask),
82 
83 	{ 0, 0 },
84 };
85 
86 static device_method_t  xics_methods[] = {
87 	/* Device interface */
88 	DEVMETHOD(device_probe,		xics_probe),
89 	DEVMETHOD(device_attach,	xics_attach),
90 
91 	{ 0, 0 },
92 };
93 
94 struct xicp_softc {
95 	struct mtx sc_mtx;
96 
97 	int ibm_int_on;
98 	int ibm_int_off;
99 	int ibm_get_xive;
100 	int ibm_set_xive;
101 
102 	/* XXX: inefficient -- hash table? tree? */
103 	struct {
104 		int irq;
105 		int vector;
106 	} intvecs[256];
107 	int nintvecs;
108 };
109 
110 static driver_t xicp_driver = {
111 	"xicp",
112 	xicp_methods,
113 	sizeof(struct xicp_softc)
114 };
115 
116 static driver_t xics_driver = {
117 	"xics",
118 	xics_methods,
119 	0
120 };
121 
122 static devclass_t xicp_devclass;
123 static devclass_t xics_devclass;
124 
125 EARLY_DRIVER_MODULE(xicp, ofwbus, xicp_driver, xicp_devclass, 0, 0,
126     BUS_PASS_INTERRUPT-1);
127 EARLY_DRIVER_MODULE(xics, ofwbus, xics_driver, xics_devclass, 0, 0,
128     BUS_PASS_INTERRUPT);
129 
130 static int
131 xicp_probe(device_t dev)
132 {
133 	if (ofw_bus_get_name(dev) == NULL || strcmp(ofw_bus_get_name(dev),
134 	    "interrupt-controller") != 0)
135 		return (ENXIO);
136 
137 	if (!ofw_bus_is_compatible(dev, "ibm,ppc-xicp"))
138 		return (ENXIO);
139 
140 	device_set_desc(dev, "PAPR virtual interrupt controller");
141 	return (BUS_PROBE_GENERIC);
142 }
143 
144 static int
145 xics_probe(device_t dev)
146 {
147 	if (ofw_bus_get_name(dev) == NULL || strcmp(ofw_bus_get_name(dev),
148 	    "interrupt-controller") != 0)
149 		return (ENXIO);
150 
151 	if (!ofw_bus_is_compatible(dev, "ibm,ppc-xics"))
152 		return (ENXIO);
153 
154 	device_set_desc(dev, "PAPR virtual interrupt source");
155 	return (BUS_PROBE_GENERIC);
156 }
157 
158 static int
159 xicp_attach(device_t dev)
160 {
161 	struct xicp_softc *sc = device_get_softc(dev);
162 	phandle_t phandle = ofw_bus_get_node(dev);
163 
164 	mtx_init(&sc->sc_mtx, "XICP", NULL, MTX_DEF);
165 	sc->nintvecs = 0;
166 
167 	sc->ibm_int_on = rtas_token_lookup("ibm,int-on");
168 	sc->ibm_int_off = rtas_token_lookup("ibm,int-off");
169 	sc->ibm_set_xive = rtas_token_lookup("ibm,set-xive");
170 	sc->ibm_get_xive = rtas_token_lookup("ibm,get-xive");
171 
172 	powerpc_register_pic(dev, OF_xref_from_node(phandle), MAX_XICP_IRQS,
173 	    1 /* Number of IPIs */, FALSE);
174 	root_pic = dev;
175 
176 	return (0);
177 }
178 
179 static int
180 xics_attach(device_t dev)
181 {
182 	phandle_t phandle = ofw_bus_get_node(dev);
183 
184 	/* The XICP (root PIC) will handle all our interrupts */
185 	powerpc_register_pic(root_pic, OF_xref_from_node(phandle),
186 	    MAX_XICP_IRQS, 1 /* Number of IPIs */, FALSE);
187 
188 	return (0);
189 }
190 
191 /*
192  * PIC I/F methods.
193  */
194 
195 static void
196 xicp_bind(device_t dev, u_int irq, cpuset_t cpumask)
197 {
198 	struct xicp_softc *sc = device_get_softc(dev);
199 	cell_t status, cpu;
200 	int ncpus, i, error;
201 
202 	/*
203 	 * This doesn't appear to actually support affinity groups, so pick a
204 	 * random CPU.
205 	 */
206 	ncpus = 0;
207 	CPU_FOREACH(cpu)
208 		if (CPU_ISSET(cpu, &cpumask)) ncpus++;
209 
210 	i = mftb() % ncpus;
211 	ncpus = 0;
212 	CPU_FOREACH(cpu) {
213 		if (!CPU_ISSET(cpu, &cpumask))
214 			continue;
215 		if (ncpus == i)
216 			break;
217 		ncpus++;
218 	}
219 
220 
221 	error = rtas_call_method(sc->ibm_set_xive, 3, 1, irq, cpu,
222 	    XICP_PRIORITY, &status);
223 	if (error < 0)
224 		panic("Cannot bind interrupt %d to CPU %d", irq, cpu);
225 }
226 
227 static void
228 xicp_dispatch(device_t dev, struct trapframe *tf)
229 {
230 	struct xicp_softc *sc;
231 	uint64_t xirr, junk;
232 	int i;
233 
234 	sc = device_get_softc(dev);
235 	for (;;) {
236 		/* Return value in R4, use the PFT call */
237 		phyp_pft_hcall(H_XIRR, 0, 0, 0, 0, &xirr, &junk, &junk);
238 		xirr &= 0x00ffffff;
239 
240 		if (xirr == 0) { /* No more pending interrupts? */
241 			phyp_hcall(H_CPPR, (uint64_t)0xff);
242 			break;
243 		}
244 		if (xirr == XICP_IPI) {		/* Magic number for IPIs */
245 			xirr = MAX_XICP_IRQS;	/* Map to FreeBSD magic */
246 			phyp_hcall(H_IPI, (uint64_t)(PCPU_GET(cpuid)),
247 			    0xff); /* Clear IPI */
248 		}
249 
250 		/* XXX: super inefficient */
251 		for (i = 0; i < sc->nintvecs; i++) {
252 			if (sc->intvecs[i].irq == xirr)
253 				break;
254 		}
255 
256 		KASSERT(i < sc->nintvecs, ("Unmapped XIRR"));
257 		powerpc_dispatch_intr(sc->intvecs[i].vector, tf);
258 	}
259 }
260 
261 static void
262 xicp_enable(device_t dev, u_int irq, u_int vector)
263 {
264 	struct xicp_softc *sc;
265 	cell_t status, cpu;
266 
267 	sc = device_get_softc(dev);
268 
269 	KASSERT(sc->nintvecs + 1 < sizeof(sc->intvecs)/sizeof(sc->intvecs[0]),
270 	    ("Too many XICP interrupts"));
271 
272 	mtx_lock(&sc->sc_mtx);
273 	sc->intvecs[sc->nintvecs].irq = irq;
274 	sc->intvecs[sc->nintvecs].vector = vector;
275 	mb();
276 	sc->nintvecs++;
277 	mtx_unlock(&sc->sc_mtx);
278 
279 	/* IPIs are also enabled */
280 	if (irq == MAX_XICP_IRQS)
281 		return;
282 
283 	/* Bind to this CPU to start: distrib. ID is last entry in gserver# */
284 	cpu = PCPU_GET(cpuid);
285 	rtas_call_method(sc->ibm_set_xive, 3, 1, irq, cpu, XICP_PRIORITY,
286 	    &status);
287 	xicp_unmask(dev, irq);
288 }
289 
290 static void
291 xicp_eoi(device_t dev, u_int irq)
292 {
293 	uint64_t xirr;
294 
295 	if (irq == MAX_XICP_IRQS) /* Remap IPI interrupt to internal value */
296 		irq = XICP_IPI;
297 	xirr = irq | (XICP_PRIORITY << 24);
298 
299 	phyp_hcall(H_EOI, xirr);
300 }
301 
302 static void
303 xicp_ipi(device_t dev, u_int cpu)
304 {
305 
306 	phyp_hcall(H_IPI, (uint64_t)cpu, XICP_PRIORITY);
307 }
308 
309 static void
310 xicp_mask(device_t dev, u_int irq)
311 {
312 	struct xicp_softc *sc = device_get_softc(dev);
313 	cell_t status;
314 
315 	if (irq == MAX_XICP_IRQS)
316 		return;
317 
318 	rtas_call_method(sc->ibm_int_off, 1, 1, irq, &status);
319 }
320 
321 static void
322 xicp_unmask(device_t dev, u_int irq)
323 {
324 	struct xicp_softc *sc = device_get_softc(dev);
325 	cell_t status;
326 
327 	if (irq == MAX_XICP_IRQS)
328 		return;
329 
330 	rtas_call_method(sc->ibm_int_on, 1, 1, irq, &status);
331 }
332 
333